tag:blogger.com,1999:blog-26266727737655349362024-03-23T03:18:08.424-07:00TS-CHEM BlogWelcome to the TS-CHEM Blog, a forum for prospective and experienced groundwater modelers, and those interested in learning more about solute transport modeling using TS-CHEM!flexAEMhttp://www.blogger.com/profile/06315034871207029515noreply@blogger.comBlogger17125tag:blogger.com,1999:blog-2626672773765534936.post-53749697198252998792023-10-13T13:19:00.001-07:002023-10-13T13:19:08.437-07:00Estimation of TS-CHEM Source Terms Using the Newly Released Soil Infiltration and Leaching Tool (SILT)<p>TS-CHEM is pleased to announce the release of the “Soil Infiltration and Leaching Tool” (SILT), a Microsoft Excel-based spreadsheet utility that allows users to simulate one-dimensional contaminant fate and transport processes though the vadose zone in a simple, user-friendly environment. The SILT utility is a perfect companion to TS-CHEM, allowing site investigators to evaluate potential impacts to groundwater associated with contaminated soil, and estimate contaminant source terms that can then be incorporated into TS-CHEM and used to estimate the extent and duration of resulting contaminant plumes. </p><p></p><br /><p></p><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhAQJHxwWr7SVa01kXMqWMzZ1j5J-xk6wzbClwUOLHmfMJRPH4wzLikdPl5kN2rQqEohyphenhyphenW_5Iw6q85_yEsQTGJUfG0fLglRJawjOOKDQ0s-lkSzns5rqwNL9sw4EGNkeoes-SNOjy2M96xOu9L2YRe9XJ_4X5uiDUkIYFUyw2aAQd5bRqyQ1yQJz-eBjT7Z/s1879/10000_R1.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="1872" data-original-width="1879" height="638" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhAQJHxwWr7SVa01kXMqWMzZ1j5J-xk6wzbClwUOLHmfMJRPH4wzLikdPl5kN2rQqEohyphenhyphenW_5Iw6q85_yEsQTGJUfG0fLglRJawjOOKDQ0s-lkSzns5rqwNL9sw4EGNkeoes-SNOjy2M96xOu9L2YRe9XJ_4X5uiDUkIYFUyw2aAQd5bRqyQ1yQJz-eBjT7Z/w640-h638/10000_R1.png" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-size: small; font-style: italic;">Figure 1: Vadose Zone Transport Conceptual Model for SILT<br /><br /></span></td></tr></tbody></table><br /><div class="separator" style="clear: both; text-align: center;"><br /></div><p></p><p>SILT simulates contaminant transport from the soil source, through the vadose zone, to a groundwater contaminant source zone in three basic steps:</p><p>1. The initial source zone water concentration, located in the Source Zone (of user-specified vertical thickness), is calculated after partitioning of the user-specified Source Zone Total Soil concentration among the solid-, air- and dissolved phases</p><p>2. The dissolved phase contaminant source is transported vertically downward through the Vadose Zone, being acted upon by dispersion and degradation processes, until it reaches the groundwater table, producing a leachate breakthrough curve</p><p>3. At the bottom of the vadose zone, leachate (at the calculated flux rate and concentration) is delivered to a mixing zone at the top of the water table. When the infiltrating soil water reaches the water table, it is mixed with groundwater and the contaminant is diluted (using a Dilution Attenuation Factor (DAF)), resulting in a lower concentration. The diluted concentration data can then be used for comparison to published groundwater standards, and/or utilized to calculate source terms for groundwater plume models (such as TS-CHEM).</p><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiQi-lCTJDDJycMIi8Rw2fFgNi3BltSTn6rX0fv-GPVcTuigj_wplOSXnmvL9gyOVmLPbnbGHDRirVOins8X1A7dQHgFLOpHDJEFZihXF1gURzE0YW27wGGkOCnUD9dZx4l9DjJl3vp8LDxN7xXmvE8A3QDgGHYo5Z-iNqhqvgxSXQWCJEhQHDcSeTyAiKr/s1821/11000_R1.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="1595" data-original-width="1821" height="560" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiQi-lCTJDDJycMIi8Rw2fFgNi3BltSTn6rX0fv-GPVcTuigj_wplOSXnmvL9gyOVmLPbnbGHDRirVOins8X1A7dQHgFLOpHDJEFZihXF1gURzE0YW27wGGkOCnUD9dZx4l9DjJl3vp8LDxN7xXmvE8A3QDgGHYo5Z-iNqhqvgxSXQWCJEhQHDcSeTyAiKr/w640-h560/11000_R1.png" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><i><span style="font-size: x-small;">Figure 2: Groundwater Source Term Conceptual Model for SILT.</span></i></td></tr></tbody></table><br /><div><br /><p class="MsoNormal">SILT’s Interface is set up in an intuitive manner, with a
series of worksheets that allow for a streamlined, step-by-step workflow. These worksheets are described below.</p><p class="MsoNormal"></p><ul style="text-align: left;"><li><span style="font-family: Symbol; text-indent: -0.25in;"><span style="font-family: "Times New Roman"; font-feature-settings: normal; font-kerning: auto; font-optical-sizing: auto; font-size: 7pt; font-stretch: normal; font-variant-alternates: normal; font-variant-east-asian: normal; font-variant-numeric: normal; font-variant-position: normal; font-variation-settings: normal; line-height: normal;"> </span></span><u style="text-indent: -0.25in;">Step 1 – Source Zone</u><span style="text-indent: -0.25in;"> – In this worksheet,
the user can specify fate and transport parameters for the contaminant of
concern in the soil source zone, as well as the amount of time soil leachate
concentrations will be calculated for, and the nature of the source (e.g.,
constant source, decaying source, or variable source concentrations), allowing
the user to estimate soil source concentrations through time.</span></li></ul><div style="text-indent: -24px;"><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEhpqqrkZaqqcV3Pse0Zx0WbNrv2FT5-MFEA546cNUKD7ijjFKQO3ucMYZ8m3PI_XAmVnjLYTdayBeODDKc0lDicLGd-KPRFbDkUyzEe7KxOhplMwZu0-MrERV2jaSL_f2m-ju0CTfxoIOM7VM6lTx5o4ALovANk9Wc0320Lq2s42XF5q4w9TT117NakqYw2" style="margin-left: auto; margin-right: auto;"><img alt="" data-original-height="403" data-original-width="859" height="188" src="https://blogger.googleusercontent.com/img/a/AVvXsEhpqqrkZaqqcV3Pse0Zx0WbNrv2FT5-MFEA546cNUKD7ijjFKQO3ucMYZ8m3PI_XAmVnjLYTdayBeODDKc0lDicLGd-KPRFbDkUyzEe7KxOhplMwZu0-MrERV2jaSL_f2m-ju0CTfxoIOM7VM6lTx5o4ALovANk9Wc0320Lq2s42XF5q4w9TT117NakqYw2=w400-h188" width="400" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-size: x-small;"><i>Figure 3: Source Concentration Input Table in SILT “Source Zone” tab.</i></span></td></tr></tbody></table><br /><br /></div><div style="text-indent: -24px;"><ul style="text-align: left;"><li> <u>Steps 2 and 3 – Vadose Zone and Mixing Zone</u> – Using the soil source zone concentrations estimated in Step 1, the Vadose Zone and Mixing Zone worksheet allows the user to input properties of the vadose zone soils (e.g., distance from bottom of source to water table, water content, and seepage velocity) and the contaminant as it migrates downward through the vadose zone (e.g., decay rates in water and soil) to estimate leachate concentrations at the bottom of the soil column.</li></ul><br /><div class="separator" style="clear: both; text-align: center;"><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh6praTRkFslS3GHyb_xqpq52nP-CEhCNHh0G9v5i4qdQcPIkGdaOeFlkRVI8DjOow7wQ6-sV9h877JScOuepoBPiA9AP8m1AFPetulLYTrpaoTmtPAluRB1KoHGJCFSYvhyJdgIY9mZg-kuBRAt6wgWDtKkv2oydMV_0DWYGlOPNGRFvZ50MxzhuLT6a2d/s1142/27000R1.PNG" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="789" data-original-width="1142" height="442" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh6praTRkFslS3GHyb_xqpq52nP-CEhCNHh0G9v5i4qdQcPIkGdaOeFlkRVI8DjOow7wQ6-sV9h877JScOuepoBPiA9AP8m1AFPetulLYTrpaoTmtPAluRB1KoHGJCFSYvhyJdgIY9mZg-kuBRAt6wgWDtKkv2oydMV_0DWYGlOPNGRFvZ50MxzhuLT6a2d/w640-h442/27000R1.PNG" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><i><span style="font-size: x-small;">Figure 4: Worksheet layout for the “2 Vadose & 3 MixingZone” Tab – Step 2</span></i></td></tr></tbody></table><br /><div class="separator" style="clear: both; text-align: center;"><br /></div><br /></div></div></div><blockquote style="border: none; margin: 0px 0px 0px 40px; padding: 0px;"><div><div style="text-align: left; text-indent: -24px;"> The leachate concentrations estimated as part of Step 2, along with a DAF value (which can be specified by the user or calculated using multiple methods) are then used to estimate dissolved-phase concentrations in mixing zone groundwater beneath the soil source zone.</div></div></blockquote><p> </p><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhXOrp2hfEJU-6Mth1NZHySIfgS__UDSEBR5Vs8TG5VpDeHZQTOBVQeO7Ya3Evad0l6uVxISG8EA0nmYkZJTk3z6vQKAmKe1ilLogoZUXPYq05nTPbspaT7WW_0LyZyQ7Pe7OA8OClfFzl3cZV4miYI31Rx4vMIKHvjUWTv_YT4asJ6M64EHE7JGyuzAtmI/s3126/31000_R1.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="2069" data-original-width="3126" height="424" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhXOrp2hfEJU-6Mth1NZHySIfgS__UDSEBR5Vs8TG5VpDeHZQTOBVQeO7Ya3Evad0l6uVxISG8EA0nmYkZJTk3z6vQKAmKe1ilLogoZUXPYq05nTPbspaT7WW_0LyZyQ7Pe7OA8OClfFzl3cZV4miYI31Rx4vMIKHvjUWTv_YT4asJ6M64EHE7JGyuzAtmI/w640-h424/31000_R1.png" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><i><span style="font-size: x-small;">Figure 5: Worksheet layout for the “2 Vadose & 3 MixingZone” Tab – Step 3</span></i></td></tr></tbody></table><br /><div class="separator" style="clear: both; text-align: left;"><br /></div><ul style="text-align: left;"><li><u style="text-decoration-line: underline;">Step 4 – Plume Model Source Steps </u><u>–</u> In this worksheet, the user can discretize the diluted mixing zone groundwater concentration data estimated in Step 3 into a specific number of source concentration steps (each with its own duration), which can then be incorporated into a groundwater contaminant plume model (such as TS-CHEM) as a source term.</li></ul><br /><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjvwHTCSc9qnpqnT1Hh35z70lGxRj8mepqr-jXGazbli9yfCsUwfHlyRJ4BpLS4s_9hJ43qyr1RNub2Ij0EBaJS3f0PcObiv01h_cUJkHVvhZmUk0avSeEETYJy__WpR_-UTG1LhVxtn475IzDNPdjgVBu1kEUNhCHDg-ATQEExFktRpA0Ouhp0iLecpt4V/s1450/40000_R1.PNG" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="653" data-original-width="1450" height="288" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjvwHTCSc9qnpqnT1Hh35z70lGxRj8mepqr-jXGazbli9yfCsUwfHlyRJ4BpLS4s_9hJ43qyr1RNub2Ij0EBaJS3f0PcObiv01h_cUJkHVvhZmUk0avSeEETYJy__WpR_-UTG1LhVxtn475IzDNPdjgVBu1kEUNhCHDg-ATQEExFktRpA0Ouhp0iLecpt4V/w640-h288/40000_R1.PNG" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><i><span style="font-size: x-small;">Figure 6: Worksheet layout for the 4 Plume Source Steps Tab.</span></i></td></tr></tbody></table><div><br /><div class="separator" style="clear: both; text-align: left;"><p class="MsoNormal">SILT also incorporates a number of features that facilitate
model input, and allow for easy export of model results. For example, SILT includes a “unit
conversion” feature, which allows the user to enter a variety of commonly used
units for most input parameters, which are automatically converted by the model
before running model calculations. This feature prevents unnecessary confusion
related to units and ensures model output is consistent and accurate, while
also allowing greater flexibility.
Additionally, users can export time series charts of model output with
the click of a button (including modeled source concentrations, leachate
concentrations, diluted groundwater concentrations in the mixing zone, and
plume model source steps). Model generated time step source concentrations can
also be exported to a comma-delimited .csv file, allowing for easy
incorporation into groundwater plume models as a source term.<o:p></o:p></p>
<p class="MsoNormal">SILT includes a detailed User Guide which provides a
comprehensive overview of the SILT utility, step-by-step instructions for all
model inputs, and thorough descriptions of the calculations that are performed
in SILT. And, if you’re not sure where to start, SILT comes packaged with a
built-in example soil leaching model that simulates migration of TCE through
the vadose zone, and is based on vadose zone fate and transport parameters
presented in Sanders (1995). Simply click the “Sanders 1995 Example Model”
button on the “1 Source Zone” tab, and all associated input parameters will be
populated in the model worksheets. </p><p class="MsoNormal">The SILT utility can be downloaded for <b>FREE</b> from the TS-CHEM website (<a href="https://www.transportstudio.com/SILT/">https://www.transportstudio.com/SILT/</a>).</p><p class="MsoNormal"><o:p></o:p></p></div><br /><br /></div><p></p><div><div style="text-indent: -24px;"><div class="separator" style="clear: both; text-align: left;"><br /></div><br /><br /></div><p></p><br /><br /></div><p><br /></p><div class="separator" style="clear: both; text-align: center;"><br /></div><br />flexAEMhttp://www.blogger.com/profile/06315034871207029515noreply@blogger.com0tag:blogger.com,1999:blog-2626672773765534936.post-7662298171234502392023-08-17T10:51:00.000-07:002023-08-17T10:51:20.342-07:00TS-CHEM Example Applications – Commingled Plume Analysis<span style="font-family: arial;">In the course of performing site investigations, environmental professionals are often tasked with identifying sources of contamination (e.g., areas where contaminants may have been discharged into site soils and may have potentially migrated to groundwater) and delineating the nature and extent of impacted groundwater. In many cases, releases of the same chemical from multiple operational area sources may form downgradient plume zones that commingle, making it difficult to distinguish which source (or sources) may be responsible for impacted groundwater. Additionally, commingling of a site groundwater plume (or plumes) with plumes from off-site sources may further complicate the determination of source contribution and responsibility for cleanup. </span><div><span style="font-family: arial;"><br /></span></div><div><span style="font-family: arial;">Although evaluating which source (or sources) of contamination at a site (or sites) may be associated with impacted groundwater when commingled plume conditions are present can be difficult, there are resources and tools that can assist environmental professionals with demonstrating that commingled plumes are present and assessing the relative contribution from individual plumes to the commingled plume. For example, New Jersey’s Commingled Plume Technical Guidance Document (which can be accessed <a href="https://www.nj.gov/dep/srp/guidance/srra/commingled_plume_guidance.pdf" target="_blank"><span style="color: #2b00fe;">HERE</span></a>) describes several types of commingled plume scenarios that may be encountered, how to investigate them, and how to develop lines of evidence to evaluate commingled plume conditions and select appropriate remedial measures. </span></div><div><span style="font-family: arial;"><br /></span></div><div><span style="font-family: arial;">One of the lines of evidence identified in the New Jersey Commingled Plume Guidance Document is solute transport modeling. With TS-CHEM, site investigators can quickly and easily perform solute transport modeling analyses to evaluate commingled plume conditions at a site and establish a clear line of evidence that demonstrates likely contribution from each source area identified, and which plume(s) may contribute to known and potential impacts to downgradient receptors. </span></div><div><span style="font-family: arial;"><br /></span></div><div><span style="font-family: arial;">This blog post will cover the fourth Example Application in the TS-CHEM Example Application series: Commingled Plume Analysis. To follow along and review the model files, you can download this example application <a href="https://transportstudio.com/example-applications.php" target="_blank"><span style="color: #2b00fe;">HERE</span></a>.</span><div><b><span style="font-family: arial;"><br /></span></b></div><div><span style="font-family: arial;"><i><u>Overview</u></i></span></div><div><span style="font-family: arial;"><br /></span></div><div><span style="font-family: arial;">
In this scenario, investigators have identified areas of concern associated with historical releases of chlorinated solvents from degreasers at two separate nearby industrial sites, resulting in the release of Trichloroethylene (TCE) to groundwater. The plumes associated with these releases have apparently commingled, resulting in a plume that extends downgradient from the sites. A well search has identified a potential receptor well 3,000 feet downgradient from one of the sites. Initial site investigations have revealed the following information:</span></div></div><div><ul style="font-family: arial; text-align: left;"><li>Aquifer material = medium sand; some gravel; little silt</li><li>Hydraulic gradient to the east = 0.003 ft/ft</li><li>Source area TCE concentrations:</li><ul><li>Source 1 = 10,000 µg/L</li><li>Source 2 = 5,000 µg/L</li></ul></ul><div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="font-family: arial; margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEg8KvrTPTkLnUtTCOxkfrXMLnCXNFDEeXuCP408MqQJ9x2fglqi50m23SFC1pJGdvWr7fH9sh-QeUjLUn2h9pUmVkqgauSnud_pJKMjEGnzsE0GTCob7iD-f9Ry7Qah7lWXimW161ZNXif5PINFADvatFJaHBGtI_zy1Vd8LaCa6wKUpGNAr5b1rWjsEKDP" style="margin-left: auto; margin-right: auto;"><img alt="" data-original-height="563" data-original-width="1039" height="346" src="https://blogger.googleusercontent.com/img/a/AVvXsEg8KvrTPTkLnUtTCOxkfrXMLnCXNFDEeXuCP408MqQJ9x2fglqi50m23SFC1pJGdvWr7fH9sh-QeUjLUn2h9pUmVkqgauSnud_pJKMjEGnzsE0GTCob7iD-f9Ry7Qah7lWXimW161ZNXif5PINFADvatFJaHBGtI_zy1Vd8LaCa6wKUpGNAr5b1rWjsEKDP=w640-h346" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><p class="MsoCaption"><i><span style="font-size: x-small;">Figure <!--[if supportFields]><span style='mso-element:
field-begin'></span><span style='mso-spacerun:yes'> </span>SEQ Figure \* ARABIC
<span style='mso-element:field-separator'></span><![endif]-->1<!--[if supportFields]><span style='mso-no-proof:
yes'><span style='mso-element:field-end'></span></span><![endif]-->. Site map
showing source areas, distance to downgradient receptor well</span>.</i><span style="font-size: 12.0pt;"><o:p></o:p></span></p></td></tr></tbody></table><br /><p class="MsoNormal" style="font-family: arial;"><span style="font-size: 12.0pt; line-height: 107%;">Concerned by
potential impacts to the downgradient receptor, regulators have requested that
analyses be performed to determine whether TCE will impact the downgradient
receptor well in exceedance of applicable the standard (in this case 5 </span><span style="font-size: 12.0pt; line-height: 107%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">µ</span><span style="font-size: 12.0pt; line-height: 107%;">g/L), and if so, which site (or sites) may be responsible for
impacts to the well. <o:p></o:p></span></p>
<p class="MsoNormal" style="font-family: arial;"><span style="font-size: 12pt; line-height: 107%;"><i><u>Setting
Up the Model</u></i><b><o:p></o:p></b></span></p>
<p class="MsoNormal" style="font-family: arial;"><span style="font-size: 12.0pt; line-height: 107%;">The releases
of TCE at the two sites have resulted in the identification of Dense
Non-Aqueous Phase Liquid (DNAPL) in the subsurface, and as such, the DNAPL source
areas at the two sites are located at approximately 16 ft beneath the water
table. Because of this, 3DADE-3 is a good model solution for this analysis because
it is capable of representing the source areas as a vertical patch source at depth
and assumes a constant concentration (which is appropriate since ongoing DNAPL
sources are present beneath both sites). In TS-CHEM, the following model
parameters should be set</span></p><ul style="text-align: left;"><li style="font-family: arial;"><span style="font-family: Symbol; font-size: 12pt; line-height: 107%; text-indent: -0.25in;"><span style="font-family: "Times New Roman"; font-feature-settings: normal; font-kerning: auto; font-optical-sizing: auto; font-size: 7pt; font-stretch: normal; font-variant-alternates: normal; font-variant-east-asian: normal; font-variant-numeric: normal; font-variation-settings: normal; line-height: normal;"> </span></span><span style="font-size: 12pt; line-height: 107%; text-indent: -0.25in;">Hydraulic
gradient = 0.003 ft/t</span></li><li style="font-family: arial;"><span style="font-size: 12pt; line-height: 107%; text-indent: -0.25in;">Hydraulic
conductivity = 80 ft/d</span></li><li><div style="font-family: arial; text-indent: 0px;"><span style="font-size: 12pt; text-indent: -0.25in;">Effective
porosity = 0.25</span></div></li><li><div style="font-family: arial; text-indent: 0px;"><span style="text-indent: -0.25in;">Source
width = 20 ft</span></div></li><li><div style="font-family: arial; text-indent: 0px;"><span style="font-size: 12pt; line-height: 107%; text-indent: -0.25in;">Source
depth = 16 ft</span></div></li><li><div style="font-family: arial; text-indent: 0px;"><span style="font-size: 12pt; line-height: 107%; text-indent: -0.25in;">Source
Thickness = 4 ft</span></div></li><li><div style="font-family: arial; text-indent: 0px;"><span style="font-size: 12pt; line-height: 107%; text-indent: -0.25in;">Source
1 TCE source concentration = 10,000 </span><span style="font-size: 12pt; line-height: 107%; text-indent: -0.25in;">µ</span><span style="font-size: 12pt; line-height: 107%; text-indent: -0.25in;">g/L</span></div></li><li><div style="font-family: arial; text-indent: 0px;"><span style="font-size: 12pt; line-height: 107%; text-indent: -0.25in;">Source
1 TCE source concentration = 5,000 </span><span style="font-size: 12pt; line-height: 107%; text-indent: -0.25in;">µ</span><span style="font-size: 12pt; line-height: 107%; text-indent: -0.25in;">g/L</span></div></li></ul><p class="MsoNormal"><b><span style="font-size: 12.0pt; line-height: 107%;"><span style="font-family: arial;">Analysis
1: Assessing Potential TCE Impacts to Downgradient Receptor Well<o:p></o:p></span></span></b></p>
<p class="MsoNormal"><span style="font-family: arial;"><span style="font-size: 12.0pt; line-height: 107%;">First, a model
observation point should be set approximately 3,000 ft downgradient from Source
1 (i.e., the location of the receptor well). After running the model for approximately
40 years, the C v t plot reveals that the commingled plume first reaches the
receptor well after 10 years and stabilizes after approximately 28 years (when
concentrations begin to level off just above 30 </span><span style="font-size: 12.0pt; line-height: 107%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">µ</span><span style="font-size: 12.0pt; line-height: 107%;">g/L) (<b><i>Figure 2</i></b>).</span></span></p><p class="MsoNormal"><span style="font-family: arial;"><span style="font-size: 12.0pt; line-height: 107%;"> <table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEgdoTru5KpfrH0OoRwkHZt_cikYzxwd2wv8jJ8r7qxTDaxWTXuUbperb7LQrw6appZWcaxFhVBHMOaGtm0x4V0Y0ftJh6KHpWvmBQ9dGQbZTpLn8-z5nly37TfYghDSb4UMN1bE4mgc0xTQt2DwdB6glrvGenMKXQrDXpQsGaF_87nJkKiCRN3pFxHZKO_8" style="margin-left: auto; margin-right: auto;"><img alt="" data-original-height="575" data-original-width="990" height="372" src="https://blogger.googleusercontent.com/img/a/AVvXsEgdoTru5KpfrH0OoRwkHZt_cikYzxwd2wv8jJ8r7qxTDaxWTXuUbperb7LQrw6appZWcaxFhVBHMOaGtm0x4V0Y0ftJh6KHpWvmBQ9dGQbZTpLn8-z5nly37TfYghDSb4UMN1bE4mgc0xTQt2DwdB6glrvGenMKXQrDXpQsGaF_87nJkKiCRN3pFxHZKO_8=w640-h372" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="line-height: 107%;"><i><span style="font-size: x-small;">Figure
2. The C v t chart in TS-CHEM displaying commingled plume TCE concentrations at
the receptor well (located 3,000 ft downgradient from Source 1).</span><br /><br /></i></span></td></tr></tbody></table></span></span></p><p class="MsoNormal"><span style="font-family: arial;"><span style="font-size: 12.0pt; line-height: 107%;">Although
this analysis answers the question as to whether the commingled plume may
impact the downgradient receptor well in exceedance of the applicable standard
of 5 </span><span style="font-size: 12.0pt; line-height: 107%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;">µ</span></span><span style="font-size: 12.0pt; line-height: 107%;"><span style="font-family: arial;">g/L for TCE (it will), we also want to understand the extent
to which each of the source areas may contribute to those impacts (including
which source/plume first reaches the well, and the extent that each well
contributes to TCE impacts). This analysis can easily be done in TS-CHEM by
simply unchecking the “sum concentrations” option, which will display
individual contributions from each plume on the C v t plot.</span><o:p></o:p></span></p><p class="MsoNormal"><span style="font-size: 12.0pt; line-height: 107%;"><span style="font-family: arial;"><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEixn1i6-GdnmRqG6HbcZlDa0v5DKMD40KFqCVzWcftz8v1bxz4AA5_UpuzhDoRlCpg_j6tgBvQzdfsiLrUNayOjBCbU0X1yuSTA0lXKAgDhJhcTp6P91jxvGubl2xC_2NirCraZewZIei8cCEnnLZZYefu3wsEKWn-suJ_yhGlaM7KlUoPXN23vdZikOwMt" style="margin-left: auto; margin-right: auto;"><img alt="" data-original-height="586" data-original-width="1006" height="372" src="https://blogger.googleusercontent.com/img/a/AVvXsEixn1i6-GdnmRqG6HbcZlDa0v5DKMD40KFqCVzWcftz8v1bxz4AA5_UpuzhDoRlCpg_j6tgBvQzdfsiLrUNayOjBCbU0X1yuSTA0lXKAgDhJhcTp6P91jxvGubl2xC_2NirCraZewZIei8cCEnnLZZYefu3wsEKWn-suJ_yhGlaM7KlUoPXN23vdZikOwMt=w640-h372" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-size: x-small;"><i>Figure 3. The C v t chart in TS-CHEM displaying TCE concentrations associated with plumes from Source 1 and Source 2 at the receptor well (located 3,000 ft downgradient from Source 1).<br /></i><br /><div style="font-style: italic; text-align: left;"><br /></div></span></td></tr></tbody></table></span></span></p><p class="MsoNormal"><span style="font-family: arial;">As shown in <b><i>Figure 3</i></b>, although the plume associated with Source Area 2 is the first to reach the receptor well, with the plume from Source Area 1 arriving soon after. The plot also indicates that after about 20 years, Source Area 1 is contributing about 2/3 of the TCE in the receptor well, whereas the plume associated with Source Area 1 is contributing approximately 1/3 of the TCE (once the plumes stabilize).</span></p><p class="MsoNormal"><span style="font-family: arial;">TS-CHEM also allows for the generation of contour plots, which in this case, indicate that the plumes from the two source areas begin to commingle after approximately two years (<b><i>Figure 4</i></b>), with the commingled plume reaching a maximum extent of approximately 4,000 ft after 20 years (<b><i>Figure 5</i></b>).</span></p><div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEgg4C75dkw2NpH7fmr3eCRAx5g-nqfP8htUYw7UQKjg3LwH4PIhZKGqm0C85n0gU-ihCZBUamTSU1xVPsdPCFf_Wari6ZinqqHrHjBRT4QJgcfRL71HEW6aqDAQ3GHxpiKAdG2YcPDBKzqDUMOgFjXXUoiGbqyrZSCvAQIKGCJM_BcN4ca5WV0PC3DSKF49" style="margin-left: auto; margin-right: auto;"><img alt="" data-original-height="605" data-original-width="1040" height="372" src="https://blogger.googleusercontent.com/img/a/AVvXsEgg4C75dkw2NpH7fmr3eCRAx5g-nqfP8htUYw7UQKjg3LwH4PIhZKGqm0C85n0gU-ihCZBUamTSU1xVPsdPCFf_Wari6ZinqqHrHjBRT4QJgcfRL71HEW6aqDAQ3GHxpiKAdG2YcPDBKzqDUMOgFjXXUoiGbqyrZSCvAQIKGCJM_BcN4ca5WV0PC3DSKF49=w640-h372" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-family: arial; font-size: x-small;"><i>Figure 4. TS-CHEM's contour chart showing initial commingling of plumes after two years<br /><br /></i></span></td></tr></tbody></table><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEh20BXFxILMMNoYWF17OVuo-E-YEw7WZNqt3TWsAk88XQrkFqsV5Cc_bCVKw2s3aADQyHw1Oh5KJGV9rhbn7H_UM23QtnbTmS-SPcmzTfMkTjOlFCCODitr9hL0j_0rQcxVSQFF02JSUWhSIun4pb_d0qO8LUZwvV6tygpEyZH9tdc2n4Xh4jJbrIdqrWgI" style="font-family: arial; font-size: 12pt; margin-left: auto; margin-right: auto; text-align: center;"><img alt="" data-original-height="604" data-original-width="1040" height="372" src="https://blogger.googleusercontent.com/img/a/AVvXsEh20BXFxILMMNoYWF17OVuo-E-YEw7WZNqt3TWsAk88XQrkFqsV5Cc_bCVKw2s3aADQyHw1Oh5KJGV9rhbn7H_UM23QtnbTmS-SPcmzTfMkTjOlFCCODitr9hL0j_0rQcxVSQFF02JSUWhSIun4pb_d0qO8LUZwvV6tygpEyZH9tdc2n4Xh4jJbrIdqrWgI=w640-h372" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-family: arial; font-size: x-small;"><i>Figure 5. TS-CHEM's contour chart showing extent of commingled plume after 20 years</i></span></td></tr></tbody></table><br /></div><p class="MsoNormal"><span style="font-family: arial;"><b>Analysis 2: Evaluation of Potential TCE Impacts to Downgradient Stream </b></span></p><p class="MsoNormal"><span style="font-family: arial;">As shown in <b><i>Figure 1</i></b>, there is a stream located approximately 5,000 ft downgradient from Source Area 1, and regulators have expressed some concern as to whether the stream may be impacted by one or both of the TCE plumes above the standard 5 µg/L. To examine this, we can add an observation point in the location of the stream (i.e., 5,000 ft downgradient from Source 1), and then examine the C v t plot. As shown in <b><i>Figure 6</i></b>, the commingled plume reaches the stream after approximately 22 years and exceeds the applicable cleanup standard (5 µg/L) after approximately 30 years. But, when we examine individual plume contributions, we can see that although the plume associated with Source Area 2 reaches the stream first, the concentrations associated with that plume do not exceed the applicable cleanup standard, whereas the TCE concentrations from Source Area 1 plume do exceed the standard (<b><i>Figure 7</i></b>).</span></p><p class="MsoNormal"><span style="font-family: arial;"><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEitNAyHihFrUTOOdzF2pwXf55qGA0goPZtlUCmxOKOpdzg0JJU5XvfnRN8sDkn-X2Yy72C7JM6D4Zcq7boEWdXFH2H2ekHBJb7aHGxwoRjjPOr3HqIsyWvNcC0MxrsOHj1VYi4azIB6prbX0-Vajkyr9T1MtL-WpGt3FSyoGZnhf4dmL6Z5ZSPa_eurpw6Z" style="margin-left: auto; margin-right: auto;"><img alt="" data-original-height="617" data-original-width="1062" height="372" src="https://blogger.googleusercontent.com/img/a/AVvXsEitNAyHihFrUTOOdzF2pwXf55qGA0goPZtlUCmxOKOpdzg0JJU5XvfnRN8sDkn-X2Yy72C7JM6D4Zcq7boEWdXFH2H2ekHBJb7aHGxwoRjjPOr3HqIsyWvNcC0MxrsOHj1VYi4azIB6prbX0-Vajkyr9T1MtL-WpGt3FSyoGZnhf4dmL6Z5ZSPa_eurpw6Z=w640-h372" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-size: x-small;"><i>Figure 6. The C v t chart in TS-CHEM displaying commingled plume TCE concentrations at the stream (located 5,000 ft downgradient from Source 1).</i></span></td></tr></tbody></table><br /><br /></span></p><div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEik661Race4slzARxjnBWeMpyNKPNWtDfSK8VixHJcnqUO_6EnQEXtTZPILOFEyii4uUofiCK6_RMwTAm-yngKWKLBRB-k5qiBtwkYpo6pXnsSnstxjHBfTX9OsUmkvO0PabyRKmdLcKwYbO2p5iMSmuxNBYvuUNRoD3GwxkaOxVI7dPzixz3Mhix-SnKwG" style="margin-left: auto; margin-right: auto;"><img alt="" data-original-height="605" data-original-width="1048" height="370" src="https://blogger.googleusercontent.com/img/a/AVvXsEik661Race4slzARxjnBWeMpyNKPNWtDfSK8VixHJcnqUO_6EnQEXtTZPILOFEyii4uUofiCK6_RMwTAm-yngKWKLBRB-k5qiBtwkYpo6pXnsSnstxjHBfTX9OsUmkvO0PabyRKmdLcKwYbO2p5iMSmuxNBYvuUNRoD3GwxkaOxVI7dPzixz3Mhix-SnKwG=w640-h370" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-family: arial; font-size: x-small;"><i>Figure 7. The C v t chart in TS-CHEM displaying TCE concentrations associated with plumes from Source 1 and Source 2 at the stream (located 5,000 ft downgradient from Source 1).</i></span></td></tr></tbody></table><br /><div><span style="font-family: arial;"><b>Analysis 3: Examining A Higher Plume Degradation Rate</b></span></div><div><span style="font-family: arial;"><br /></span></div><div><span style="font-family: arial;">Oftentimes, regulatory agencies prescribe longer half-lives for constituents for the purposes of risk evaluations. In many cases, however, half-lives of contaminants like TCE may be shorter than the default degradation rates typically prescribed by regulatory agencies. In the analyses performed thus far, a TCE half-life of 10 years was assumed. For this analysis, we want to examine TCE impacts at both the receptor well and the stream if the TCE half-life of the plume is shortened to 4.5 years.</span></div><div><br /></div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEhrkHCl5SgW015qugnULAMWsyeQiDr26PaISeAv2olXIN1Fiwg2K_yHYPrxLWWGCg2_FVa5XspmeJ7J4tlZ_9MDS1r7xP8vQ3-lPtYWgehBmwA284P2WHaCcH8eKr_Q4JqQL9vT-0IO_VrQXEeCX-WULACyFFxlv3vK_7yzkewc9iGDan9XoYUQbXO6jOxX" style="margin-left: auto; margin-right: auto;"><img alt="" data-original-height="618" data-original-width="1054" height="376" src="https://blogger.googleusercontent.com/img/a/AVvXsEhrkHCl5SgW015qugnULAMWsyeQiDr26PaISeAv2olXIN1Fiwg2K_yHYPrxLWWGCg2_FVa5XspmeJ7J4tlZ_9MDS1r7xP8vQ3-lPtYWgehBmwA284P2WHaCcH8eKr_Q4JqQL9vT-0IO_VrQXEeCX-WULACyFFxlv3vK_7yzkewc9iGDan9XoYUQbXO6jOxX=w640-h376" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-family: arial; font-size: x-small;"><i>Figure 8. TS-CHEM's contour chart showing extent of commingled plume with shorter TCE half-life after 20 years.</i></span></td></tr></tbody></table><br /><span style="font-family: arial;">The contour chart shown in <b><i>Figure 8</i></b> indicates that after 20 years, the commingled plume boundary is reduced by approximately 500 ft when compared to Analysis 1 when the TCE half-life is reduced to 4.5 years. As shown in the C v t plot in <b><i>Figure 9</i></b>, although the commingled plume TCE concentration still exceed the applicable standard of 5 µg/L at the receptor well, concentrations do not exceed the standard at the downgradient stream. </span></div><div><span style="font-family: arial;"><br /></span></div><div><span style="font-family: arial;"><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEh88Na3_UEPzwLODVps5YXgkRVLjDOjQo2BmIrP_8VN0fv0B8uq5C5n7ldqAT3Rc9j8vy_eVrjZ7A7kkigXlS7-6FSow4gkkp0-c1QbPE_auDjqNfqCyEUmFJfBrShx2uTb9tVQODLl1g2FT_97OcVVrwxXwpj1UOdx81bzBB6bB0hSQCf1aj7CwsyjqQTg" style="margin-left: auto; margin-right: auto;"><img alt="" data-original-height="585" data-original-width="1009" height="372" src="https://blogger.googleusercontent.com/img/a/AVvXsEh88Na3_UEPzwLODVps5YXgkRVLjDOjQo2BmIrP_8VN0fv0B8uq5C5n7ldqAT3Rc9j8vy_eVrjZ7A7kkigXlS7-6FSow4gkkp0-c1QbPE_auDjqNfqCyEUmFJfBrShx2uTb9tVQODLl1g2FT_97OcVVrwxXwpj1UOdx81bzBB6bB0hSQCf1aj7CwsyjqQTg=w640-h372" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-size: x-small;"><i>Figure 9. The C v t chart in TS-CHEM displaying TCE concentrations associated with plumes from Source 1 and Source 2 at the receptor well and stream (assuming a 4.5-year TCE half-life).</i><br /><br /><div style="text-align: left;"><p class="MsoNormal" style="font-style: italic;"><b><span style="font-size: 12.0pt; line-height: 107%;">Conclusion<o:p></o:p></span></b></p>
<span style="font-size: 12pt; line-height: 107%;">T</span><span style="font-size: 12pt; line-height: 107%;">he presence of commingled plume conditions at
sites can be challenging for environmental professionals responsible for
investigating and remediating impacted groundwater, making it difficult to determine
the extent to which sources may contributing to the commingled plume, and in
turn, who may be responsible for cleaning them up. In this exercise, we demonstrated
how TS-CHEM can be used to perform quick and easy analyses that allow site
investigators to not only quantify the impacts of the commingled plume (e.g.,
impacts to downgradient receptors), but also evaluate the individual
contributions from each source. This line of evidence (along with other lines</span><span style="font-size: 12pt; line-height: 107%;">
of evidence developed by the site investigator) can be used to determine which
party (or parties) may be responsible for impacted groundwater, and in turn,
who should pay for the associated investigation and cleanup. </span></div></span></td></tr></tbody></table><br /><br /></span></div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td class="tr-caption" style="text-align: center;"><span style="line-height: 107%;"><i><span style="font-family: arial;"><div style="text-align: left;"></div></span></i></span></td></tr></tbody></table><p class="MsoNormal"><span style="font-family: arial;"><span style="font-size: 12.0pt; line-height: 107%;"><o:p></o:p></span></span></p><div style="text-indent: -24px;"><span style="font-family: arial;"><br /></span></div><div style="text-indent: -24px;"><span style="font-family: arial;"><br /></span></div><p class="MsoListParagraphCxSpLast" style="font-family: arial; text-indent: -0.25in;"><span style="font-size: 12.0pt; line-height: 107%;"><o:p></o:p></span></p></div></div>flexAEMhttp://www.blogger.com/profile/06315034871207029515noreply@blogger.com0tag:blogger.com,1999:blog-2626672773765534936.post-89268751819440146352023-07-26T14:15:00.000-07:002023-07-26T14:15:25.817-07:00TS-CHEM Solution Library - AT123D-AT<p><span style="text-align: justify;">The TS-CHEM program provides an easy-to-use
software environment in which to analyze contaminant plume transport, and includes
a </span><i style="text-align: justify;"><span style="color: #ed7d31; mso-themecolor: accent2;">comprehensive library
of more than 30 different analytical solutions </span></i><span style="text-align: justify;">to the advection-dispersion equatio</span><span style="text-align: justify;">n</span><i style="text-align: justify;">.</i><span style="text-align: justify;">
Each solution incorporates different capabilities, including how it represents the
contaminant source and how the plume interacts with the aquifer. For this post
in the Solution Library series, we will be focusing on the AT123D-AT family of
models published by Dan Burnell in 2012 which represents an updated version of
the original AT123D model suite developed by G.T. Yeh at the Oak Ridge National
Laboratory.</span></p><p class="MsoNormal" style="text-align: justify;"><o:p></o:p></p>
<p class="MsoNormal" style="text-align: justify;"><u>What is<i> </i>AT123D?<o:p></o:p></u></p>
<p class="MsoNormal" style="text-align: justify;">The original AT123D was a suite
of analytical model solutions that are used to simulate one-, two- and
three-dimensional transport in groundwater. The program is complex, and allows
for many different source configurations, including</p><p class="MsoNormal" style="text-align: justify;"></p><ul><li><i><span style="color: #ed7d31; mso-themecolor: accent2;">patch</span></i> <i><span style="color: #ed7d31; mso-themecolor: accent2;">sources</span></i></li><li><i><span style="color: #ed7d31; mso-themecolor: accent2;">line sources</span></i></li><li><i><span style="color: #ed7d31; mso-themecolor: accent2;">point sources</span></i></li><li><i><span style="color: #ed7d31; mso-themecolor: accent2;">volume sources</span></i></li></ul><p></p><p class="MsoNormal" style="margin-left: .25in; text-align: justify;"><o:p></o:p></p>
<p class="MsoNormal" style="margin-top: 12.0pt; text-align: justify;">In contrast to
many analytical plume models that represent the source using a first-type
specified concentration, AT123D represents the source as a second-type
specified mass flux boundary condition. This means, for example, if you know
the nitrogen load from a residential dwelling to a septic system (i.e. number
of residents times average daily nitrogen load per person) you can represent
that source in AT123D as milligrams of nitrogen per day instead of trying to
estimate a septic source concentration value. The primary difference between <b>AT123D</b>
and <b>AT123D-AT</b> is in how the solver arrives at a solution to the
advection-dispersion equation. AT123D-AT incorporates a Romberg numerical
integration scheme that works to prevent oscillations, speed convergence, and
improve accuracy for a wide range of input parameter combinations.<o:p></o:p></p>
<p class="MsoNormal" style="text-align: justify;">A conceptualization of the many
possible specified mass flux source geometries available in AT123D-AT is shown
in Figure 1 below, and can also be found in the <span class="MsoHyperlink"><i><span style="color: #ed7d31; mso-themecolor: accent2; text-decoration: none; text-underline: none;">Model Selection Tool</span></i></span><span style="color: #ed7d31; mso-themecolor: accent2;"> </span>in TS-CHEM:<o:p></o:p></p><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjfaRMZzu0adV9HxKe1VsjaaY_RWN2KrVtytanHbwOApPyiKJ8IceypnF1fRM_6jzIJKhH70gf5z4RkuudzEKTa_MgugKxxmhEhP831Lsh9_qavAI_vryPq1s1KxzAjk-07cUb4fyduav0JLEOqd2_bKIOk48mU31jL6Smwn-Ew7NcnjdRVkH-MXbuBpu5S/s467/Figure%201.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="387" data-original-width="467" height="331" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjfaRMZzu0adV9HxKe1VsjaaY_RWN2KrVtytanHbwOApPyiKJ8IceypnF1fRM_6jzIJKhH70gf5z4RkuudzEKTa_MgugKxxmhEhP831Lsh9_qavAI_vryPq1s1KxzAjk-07cUb4fyduav0JLEOqd2_bKIOk48mU31jL6Smwn-Ew7NcnjdRVkH-MXbuBpu5S/w400-h331/Figure%201.png" width="400" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Figure 1 - AT123D-AT Source Geometries<br /></td></tr></tbody></table><div class="separator" style="clear: both; text-align: center;"><br /></div><p class="MsoNormal" style="text-align: justify;">TS-CHEM was developed with
usability in mind, so the numerous AT123D-AT solutions available to the user
(differing aquifer geometries, source geometries, and source types) have been
broken up into six “versions” (see table below). These pre-configured versions
allow the user to select the type of AT123D-AT model that will best represent
their site (aquifer and source), and to specify the desired parameter input
values to represent site-specific properties, using model types that closely
match conditions simulated by other analytical ADE solutions included in <span style="color: #ed7d31; mso-themecolor: accent2;"><i>TS-CHEM’s Solution Library</i></span>.<span style="color: #ed7d31; mso-themecolor: accent2;"> </span>This last consideration
makes it easier to compare different plume transport solutions (e.g. a
first-type source vs a second-type source) by selecting similar type models
(e.g. with aquifer boundaries or without aquifer boundaries) from the <i><span style="color: #ed7d31; mso-themecolor: accent2;">TS-CHEM Solution Library</span></i>.<span style="color: #ed7d31; mso-themecolor: accent2;"><o:p></o:p></span></p><p class="MsoNormal" style="text-align: justify;"></p><p class="MsoNormal" style="text-align: justify;">The following nomenclature is
used between each version to help the user quickly determine which version they
are looking for: Infinite boundary (I), Finite boundary (F), Constant mass
release rate (C), Instantaneous release source (I), Time-variable (transient)
mass flux (T): <o:p></o:p></p><table border="1" cellpadding="0" cellspacing="0" class="MsoTableGrid" style="border-collapse: collapse; border: none; mso-border-alt: solid windowtext .5pt; mso-padding-alt: 0in 5.4pt 0in 5.4pt; mso-yfti-tbllook: 1184;">
<tbody><tr style="mso-yfti-firstrow: yes; mso-yfti-irow: 0;">
<td style="background: #FFC000; border: solid windowtext 1.0pt; mso-border-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 71.75pt;" valign="top" width="96">
<p align="center" class="MsoNormal" style="line-height: normal; margin-bottom: 0in; text-align: center;"><b><span style="color: black; mso-color-alt: windowtext;">Model
Version</span><o:p></o:p></b></p>
</td>
<td style="background: #FFC000; border-left: none; border: solid windowtext 1.0pt; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 1.5in;" valign="top" width="144">
<p align="center" class="MsoNormal" style="line-height: normal; margin-bottom: 0in; text-align: center;"><b><span style="color: black; mso-color-alt: windowtext;">Aquifer
Boundary</span><o:p></o:p></b></p>
</td>
<td style="background: #FFC000; border-left: none; border: solid windowtext 1.0pt; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 1.75in;" valign="top" width="168">
<p align="center" class="MsoNormal" style="line-height: normal; margin-bottom: 0in; text-align: center;"><b><span style="color: black; mso-color-alt: windowtext;">Source
Type</span><o:p></o:p></b></p>
</td>
<td style="background: #FFC000; border-left: none; border: solid windowtext 1.0pt; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 161.75pt;" valign="top" width="216">
<p align="center" class="MsoNormal" style="line-height: normal; margin-bottom: 0in; text-align: center;"><b><span style="color: black; mso-color-alt: windowtext;">Analagous
TS-CHEM models</span><o:p></o:p></b></p>
</td>
</tr>
<tr style="mso-yfti-irow: 1;">
<td style="border-top: none; border: solid windowtext 1.0pt; mso-border-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 71.75pt;" valign="top" width="96">
<p class="MsoNormal" style="line-height: normal; margin-bottom: 0in;"><b><span style="font-size: 10.0pt;">AT123D-AT IC<o:p></o:p></span></b></p>
</td>
<td style="border-bottom: solid windowtext 1.0pt; border-left: none; border-right: solid windowtext 1.0pt; border-top: none; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 1.5in;" valign="top" width="144">
<p class="MsoNormal" style="line-height: normal; margin-bottom: 0in;">Infinite
unbounded<o:p></o:p></p>
</td>
<td style="border-bottom: solid windowtext 1.0pt; border-left: none; border-right: solid windowtext 1.0pt; border-top: none; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 1.75in;" valign="top" width="168">
<p class="MsoNormal" style="line-height: normal; margin-bottom: 0in;">Constant mass
flux<o:p></o:p></p>
</td>
<td style="border-bottom: solid windowtext 1.0pt; border-left: none; border-right: solid windowtext 1.0pt; border-top: none; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 161.75pt;" valign="top" width="216">
<p class="MsoNormal" style="line-height: normal; margin-bottom: 0in;">3DADE-3 or
3DADE-4 (patch source)<o:p></o:p></p>
</td>
</tr>
<tr style="mso-yfti-irow: 2;">
<td style="border-top: none; border: solid windowtext 1.0pt; mso-border-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 71.75pt;" valign="top" width="96">
<p class="MsoNormal" style="line-height: normal; margin-bottom: 0in;"><b><span style="font-size: 10.0pt;">AT123D-AT II<o:p></o:p></span></b></p>
</td>
<td style="border-bottom: solid windowtext 1.0pt; border-left: none; border-right: solid windowtext 1.0pt; border-top: none; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 1.5in;" valign="top" width="144">
<p class="MsoNormal" style="line-height: normal; margin-bottom: 0in;">Infinite
unbounded<o:p></o:p></p>
</td>
<td style="border-bottom: solid windowtext 1.0pt; border-left: none; border-right: solid windowtext 1.0pt; border-top: none; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 1.75in;" valign="top" width="168">
<p class="MsoNormal" style="line-height: normal; margin-bottom: 0in;">Initial mass
instantaneous release<o:p></o:p></p>
</td>
<td style="border-bottom: solid windowtext 1.0pt; border-left: none; border-right: solid windowtext 1.0pt; border-top: none; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 161.75pt;" valign="top" width="216">
<p class="MsoNormal" style="line-height: normal; margin-bottom: 0in;">3DADE-5 or
3DADE-6 (volume source)<o:p></o:p></p>
</td>
</tr>
<tr style="mso-yfti-irow: 3;">
<td style="border-top: none; border: solid windowtext 1.0pt; mso-border-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 71.75pt;" valign="top" width="96">
<p class="MsoNormal" style="line-height: normal; margin-bottom: 0in;"><b><span style="font-size: 10.0pt;">AT123D-AT IT<o:p></o:p></span></b></p>
</td>
<td style="border-bottom: solid windowtext 1.0pt; border-left: none; border-right: solid windowtext 1.0pt; border-top: none; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 1.5in;" valign="top" width="144">
<p class="MsoNormal" style="line-height: normal; margin-bottom: 0in;">Infinite
unbounded<o:p></o:p></p>
</td>
<td style="border-bottom: solid windowtext 1.0pt; border-left: none; border-right: solid windowtext 1.0pt; border-top: none; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 1.75in;" valign="top" width="168">
<p class="MsoNormal" style="line-height: normal; margin-bottom: 0in;">Constant
specified concentration <o:p></o:p></p>
</td>
<td style="border-bottom: solid windowtext 1.0pt; border-left: none; border-right: solid windowtext 1.0pt; border-top: none; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 161.75pt;" valign="top" width="216">
<p class="MsoNormal" style="line-height: normal; margin-bottom: 0in;">ATRANS4 (with
concentration stepping)<o:p></o:p></p>
</td>
</tr>
<tr style="mso-yfti-irow: 4;">
<td style="border-top: none; border: solid windowtext 1.0pt; mso-border-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 71.75pt;" valign="top" width="96">
<p class="MsoNormal" style="line-height: normal; margin-bottom: 0in;"><b><span style="font-size: 10.0pt;">AT123D-AT FC<o:p></o:p></span></b></p>
</td>
<td style="border-bottom: solid windowtext 1.0pt; border-left: none; border-right: solid windowtext 1.0pt; border-top: none; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 1.5in;" valign="top" width="144">
<p class="MsoNormal" style="line-height: normal; margin-bottom: 0in;">Finite
bounded<o:p></o:p></p>
</td>
<td style="border-bottom: solid windowtext 1.0pt; border-left: none; border-right: solid windowtext 1.0pt; border-top: none; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 1.75in;" valign="top" width="168">
<p class="MsoNormal" style="line-height: normal; margin-bottom: 0in;">Constant mass
flux<o:p></o:p></p>
</td>
<td style="border-bottom: solid windowtext 1.0pt; border-left: none; border-right: solid windowtext 1.0pt; border-top: none; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 161.75pt;" valign="top" width="216">
<p class="MsoNormal" style="line-height: normal; margin-bottom: 0in;">ATRANS1<o:p></o:p></p>
</td>
</tr>
<tr style="mso-yfti-irow: 5;">
<td style="border-top: none; border: solid windowtext 1.0pt; mso-border-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 71.75pt;" valign="top" width="96">
<p class="MsoNormal" style="line-height: normal; margin-bottom: 0in;"><b><span style="font-size: 10.0pt;">AT123D-AT FI<o:p></o:p></span></b></p>
</td>
<td style="border-bottom: solid windowtext 1.0pt; border-left: none; border-right: solid windowtext 1.0pt; border-top: none; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 1.5in;" valign="top" width="144">
<p class="MsoNormal" style="line-height: normal; margin-bottom: 0in;">Finite
bounded<o:p></o:p></p>
</td>
<td style="border-bottom: solid windowtext 1.0pt; border-left: none; border-right: solid windowtext 1.0pt; border-top: none; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 1.75in;" valign="top" width="168">
<p class="MsoNormal" style="line-height: normal; margin-bottom: 0in;">Initial mass
instantaneous release<o:p></o:p></p>
</td>
<td style="border-bottom: solid windowtext 1.0pt; border-left: none; border-right: solid windowtext 1.0pt; border-top: none; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 161.75pt;" valign="top" width="216">
<p class="MsoNormal" style="line-height: normal; margin-bottom: 0in;">3DADE-5 or
3DADE-6 (volume source)<o:p></o:p></p>
</td>
</tr>
<tr style="mso-yfti-irow: 6; mso-yfti-lastrow: yes;">
<td style="border-top: none; border: solid windowtext 1.0pt; mso-border-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 71.75pt;" valign="top" width="96">
<p class="MsoNormal" style="line-height: normal; margin-bottom: 0in;"><b><span style="font-size: 10.0pt;">AT123D-AT FT<o:p></o:p></span></b></p>
</td>
<td style="border-bottom: solid windowtext 1.0pt; border-left: none; border-right: solid windowtext 1.0pt; border-top: none; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 1.5in;" valign="top" width="144">
<p class="MsoNormal" style="line-height: normal; margin-bottom: 0in;">Finite
bounded<o:p></o:p></p>
</td>
<td style="border-bottom: solid windowtext 1.0pt; border-left: none; border-right: solid windowtext 1.0pt; border-top: none; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 1.75in;" valign="top" width="168">
<p class="MsoNormal" style="line-height: normal; margin-bottom: 0in;">Constant
specified concentration <o:p></o:p></p>
</td>
<td style="border-bottom: solid windowtext 1.0pt; border-left: none; border-right: solid windowtext 1.0pt; border-top: none; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt; padding: 0in 5.4pt 0in 5.4pt; width: 161.75pt;" valign="top" width="216">
<p class="MsoNormal" style="line-height: normal; margin-bottom: 0in;">ATRANS4 (with
concentration stepping)<o:p></o:p></p>
</td>
</tr>
</tbody></table><br /><p></p><p class="MsoNormal" style="text-align: justify;"></p><p class="MsoNormal" style="text-align: justify;"><u>What are the differences
between the AT123D-AT models?<o:p></o:p></u></p>
<p class="MsoNormal" style="text-align: justify;">The two defining factors that highlight
the differences between the different AT123D-AT models are 1) whether the
aquifer extent is assumed to be infinite (as is the case for many analytical
transport solutions) or finite (bounded horizontally or vertically), and 2) how
the source concentration or flux is applied at the model boundary over time
(continuous, instantaneous pulse release, or time-varying). The three different
types of source concentration fluxes are conceptualized in Figure 2 below:</p><p></p><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjyBOGUWKBxp21bx8N2O95K7a_8aK4y9opFBIUjpCRaZiVk-YlAhGYHu82uPxWXnwYiKYaia2ZzZpQAQwJLXRsuRMauKTWk6sgyVpwYwX6hgd05jH6U4eO0WKETCSv3zBAKu2V-cSeoUP4X5oO7je0WBM1ApjC9CuRpgf2eSA8NjIXRRgKJhPo5EEqIlqdX/s2394/Figure%202.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="1967" data-original-width="2394" height="329" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjyBOGUWKBxp21bx8N2O95K7a_8aK4y9opFBIUjpCRaZiVk-YlAhGYHu82uPxWXnwYiKYaia2ZzZpQAQwJLXRsuRMauKTWk6sgyVpwYwX6hgd05jH6U4eO0WKETCSv3zBAKu2V-cSeoUP4X5oO7je0WBM1ApjC9CuRpgf2eSA8NjIXRRgKJhPo5EEqIlqdX/w400-h329/Figure%202.png" width="400" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Figure 2 - AT123D-AT Model Source Types<br /></td></tr></tbody></table><br /><div><p class="MsoNormal" style="text-align: justify;">As you can see in Figure 2, there
are three distinct source types. The source type that is most appropriate to
use in a particular application is dependent on the known conditions at a site,
and/or the known or assumed conditions of the source. <o:p></o:p></p><p class="MsoNormal" style="text-align: justify;"><u>What applications are the AT123D
models best suited for?</u><o:p></o:p></p>
<p class="MsoNormal" style="text-align: justify;">As discussed in previous blog
posts, TS-CHEM can assist environmental professionals with the development of
conceptual site models (CSMs) that characterize the extent and behavior of
groundwater contaminant plumes. The AT123D-AT models are highly flexible, able to
provide users with the ability to evaluate solute fate and transport in one-,
two- or three-dimensions. In its fundamental form, AT123D-AT is solving the 3D
ADE equation in a 1D (X-direction only) aquifer flow field, but 2D plume
transport and even 1D “column” transport can be set up using the bounded
aquifer settings. i.e. the AT123D-AT “F” models (<b><i><span style="color: #ed7d31; mso-themecolor: accent2;">FC, FI, and FT</span></i></b>) can be used to represent
sites where the aquifer thickness and/or width is known or is believed to be
bounded (<i><span style="color: #ed7d31; mso-themecolor: accent2;">finite aquifer
boundary</span></i>). This type of AT123D-AT model is similar to the ATRANS
family of models which include an upper (water table) and lower (aquifer base)
no-mass-flux boundary.<o:p></o:p></p>
<p class="MsoNormal" style="text-align: justify;">But the AT123D-AT models are not
all limited to bounded aquifer conditions. The AT123D-AT “I” models (<b><i><span style="color: #ed7d31; mso-themecolor: accent2;">FI, II, and IT</span></i></b>) can
be used to represent sites where there is no limitation on aquifer thickness or
width (<i><span style="color: #ed7d31; mso-themecolor: accent2;">infinite aquifer
boundary</span></i>). This type of AT123D-AT model is similar to the 3DADE
family of models, which do not impose any finite boundaries on the aquifer.<o:p></o:p></p>
<p class="MsoNormal" style="text-align: justify;">Further, the investigator can use
a variety of patch source geometries to best represent the conditions at their
site. For example, if an investigator has information on source mass flux at
the downgradient edge of a source area, they may use a <i><span style="color: #ed7d31; mso-themecolor: accent2;">patch source</span></i>. Or, if a
large regional scale model is being considered, the user may want to utilize a <i><span style="color: #ed7d31; mso-themecolor: accent2;">point source </span></i>to track
the general plume behavior over time. <o:p></o:p></p>
<p class="MsoNormal" style="text-align: justify;">When choosing between source
types, a user may choose to use a <i><span style="color: #ed7d31; mso-themecolor: accent2;">constant mass release</span></i><span style="color: #ed7d31; mso-themecolor: accent2;"> <i>source</i> </span>AT123D-AT model If only a single source
concentration is known, and/or the investigator wished to perform a
conservative analysis in which the source does not deplete through time. If the
user wanted to investigate the plume behavior in a case where a slug of solute
is introduced into the groundwater, they can use an <i><span style="color: #ed7d31; mso-themecolor: accent2;">instantaneous release source</span></i> type. If
information is available on the changing history (both increases and decreases)
of source flux over time, the <i><span style="color: #ed7d31; mso-themecolor: accent2;">transient source</span></i> type can be used. <o:p></o:p></p>
<p class="MsoNormal" style="text-align: justify;">Similar to the <span style="color: #ed7d31; mso-themecolor: accent2;">ATRANS1 model</span>, the <b>AT123D-AT
FC</b> model is useful for simulating scenarios that have aquifers of a finite
extent that can be represented by a continuous mass flux. This type of analysis
may be useful for evaluating a conservative maximum plume extent, or when the
plume becomes stable <a style="mso-comment-date: 20230726T1620; mso-comment-reference: MP_1;">(Figure 3):</a></p><p class="MsoNormal" style="text-align: justify;"><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEghH-qMIxX9vqWw3oNyF6LIl3uvluLoU9xYclxEjYk4I86ad60qvna_IHSfUY9easWY5x1jk-F_bsmltuGcXAJwSvpAkV4789R7AAPiugbbUAuyqM4J6V8g9qjlsDajxkp1gkq9wIsVu35hsfuy2St2tcatKANS84nnPpV-KGjs89VS6C11bYw1kJiA5MnM/s624/Figure%203.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="340" data-original-width="624" height="347" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEghH-qMIxX9vqWw3oNyF6LIl3uvluLoU9xYclxEjYk4I86ad60qvna_IHSfUY9easWY5x1jk-F_bsmltuGcXAJwSvpAkV4789R7AAPiugbbUAuyqM4J6V8g9qjlsDajxkp1gkq9wIsVu35hsfuy2St2tcatKANS84nnPpV-KGjs89VS6C11bYw1kJiA5MnM/w640-h347/Figure%203.png" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Figure 3 - AT123D-AT FC solution showing maximum plume extent for a stable benzene plume with a constant source flux of 0.001 ld/d at 200ft, 600ft and 1000ft from the source.</td></tr></tbody></table><br />The <b>AT123D-AT FI </b>model is
useful for simulating scenarios where a slug of contaminant is assumed to have rapidly
entered the groundwater. This type of model is sometimes used in an emergency
spill response analysis if an investigator wants to simulate a conservative
condition where a “slug” of contaminant enters the groundwater instantaneously and
then is allowed to flush away from the spill area toward a possible receptor
location (Figure 4):</p><p class="MsoNormal" style="text-align: justify;"><o:p></o:p></p></div><br /><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj9ntM0jTedTQScvESEhqnsa2LY3g-Ilri5pC7sR71RJ10tOOuOAwmHMk2zrgEXTWAgrkW9uPrbPJD5REcTsEFBN1FXumA5M98wv240fLcAb9a5TyHj11jHmWcUOVJwAmxxf0wPZCOHqbvJ3pHjo7cJLDR9D16Kf79kJ2uEk1VqJ1SyIZB0Nw4ssTDraCoW/s627/Figure%204.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="353" data-original-width="627" height="360" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj9ntM0jTedTQScvESEhqnsa2LY3g-Ilri5pC7sR71RJ10tOOuOAwmHMk2zrgEXTWAgrkW9uPrbPJD5REcTsEFBN1FXumA5M98wv240fLcAb9a5TyHj11jHmWcUOVJwAmxxf0wPZCOHqbvJ3pHjo7cJLDR9D16Kf79kJ2uEk1VqJ1SyIZB0Nw4ssTDraCoW/w640-h360/Figure%204.png" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Figure 4 - AT123D-AT FI solution showing plume concentrations up to 4000 days after an instantaneous mass input of 22.05 lbs of benzene introduced to groundwater. Concentrations are shown at 200ft, 600ft and 1000ft from the source. </td></tr></tbody></table><div><p class="MsoNormal" style="text-align: justify;">Similar to the <b><span style="color: #ed7d31; mso-themecolor: accent2;">ATRANS4</span></b><span style="color: #ed7d31; mso-themecolor: accent2;"> <b>model</b></span>, the <b>AT123D-AT
FT model </b>allows the user to define transient source behavior. Unlike
ATRANS4, the AT123D-AT FT model uses a second-type boundary condition and is
therefore defined by time-flux pairs (instead of time-concentration pairs). The
transient source condition allows the user great flexibility in how they define
the time series of their source and can enable investigators to simulate
complex scenarios where there may be intermittent single sources, multiple
sources that overlap at different times, or even source termination that would
result from remedial actions. <o:p></o:p></p>
<p class="MsoNormal" style="text-align: justify;">An example of a time-variable
source flux is shown in Figure 5 below for a hypothetical release from an
underground storage tank (UST). The benzene source progressively decreases
until it eventually reaches zero after 2000 days. This might be indicative of a
UST that leaks over time, or it could be indicative of a UST removal at around
500 days with a small amount of product remaining after removal. In either
case, the benzene concentration is reduced over time through degradation/natural
attenuation and flushing. <o:p></o:p></p><br /></div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhfByS8v5xSvRbAfS8d1RBypUHjtJRBUeSdGeT4CQD4Zj3MethOJALqvDP-0nyjo4x2jeD6hMuAtD0a0fRXz9e5cKB-mfLBVc9x_BEqW8bbjGcmS1M-GouSa4avQDNrJcYxlc6pjdiaUuWzeq73IQQqD2lKlEpAqwAvsNgyAUbCVeAisC7yIpxGdwTZ_eo-/s628/Figure%205.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="354" data-original-width="628" height="360" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhfByS8v5xSvRbAfS8d1RBypUHjtJRBUeSdGeT4CQD4Zj3MethOJALqvDP-0nyjo4x2jeD6hMuAtD0a0fRXz9e5cKB-mfLBVc9x_BEqW8bbjGcmS1M-GouSa4avQDNrJcYxlc6pjdiaUuWzeq73IQQqD2lKlEpAqwAvsNgyAUbCVeAisC7yIpxGdwTZ_eo-/w640-h360/Figure%205.png" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Figure 5 - AT123D-AT FT solution showing benzene plume concentrations entering groundwater from a hypothetical underground storage tank at 200ft, 600ft and 1000ft from the source.</td></tr></tbody></table><br /><div><p class="MsoNormal" style="text-align: justify;">To summarize: the AT123D-AT
family of models available in the <a href="https://transportstudio.com/downloads/TS-CHEM Solutions Features.pdf"><span style="color: #2b00fe;">TS-CHEM Solution Library</span></a> allow for a very flexible representation of the source
over space <i>and</i> through time and can be used for a variety of
environmental scenarios and conditions. The feature that sets the AT123D-AT
models apart is that they are the only models in the TS-CHEM solution library
that utilize a second-type (specified mass flux) source boundary condition,
allowing for users to directly input an estimate of source mass flux for their
site. AT123D-AT also differs from AT123D in that it incorporates enhanced
solver capabilities that reduce solve times and increase solution accuracy. The
six AT123D-AT model types included in TS-CHEM allow a user to easily identify which
model is best for their site or application. These models can assume either a
finite or infinite aquifer boundary and a multitude of source geometries and
source release types. <o:p></o:p></p>
<p class="MsoNormal" style="text-align: justify;">To learn more about TS-CHEM, or
to download a <a href="https://transportstudio.com/pricing.php">FREE DEMO
VERSION</a> of the software, visit the <a href="https://transportstudio.com/">TS-CHEM
Website</a> today!<o:p></o:p></p><br /></div>flexAEMhttp://www.blogger.com/profile/06315034871207029515noreply@blogger.com0tag:blogger.com,1999:blog-2626672773765534936.post-3314843760801649062023-06-16T07:29:00.003-07:002023-06-16T07:47:59.843-07:00Darcy’s Law Groundwater Velocity and Plume Arrival Time<p>In his 1999 article titled “On Misuse of the Simplest Transport Model”<sup>1</sup> Ernesto Baca explained why it is not a good idea to calculate the rate of travel of a contaminant plume front, or its time of arrival at a receptor location, using the Darcy’s Law groundwater velocity. The missing factor is dispersion.</p><p>Baca noted that the Darcy’s Law velocity equation: </p><p>V = Ki/n</p><p>only accounts for advection of the dissolved contaminant. He stated that, by measuring the plume from the source location to the far extent of the tip of the plume, one is implicitly considering both advection and dispersion. Therefore, for a relatively mobile dissolved contaminant being transported by seeping groundwater, the larger the dispersive effects, the more your estimate of arrival time will be off.</p><p>The toe of the contaminant plume will arrive earlier (i.e. in less time) that you would predict based on a Darcy’s Law groundwater velocity estimate.</p><p>The process is depicted in this video:</p><div class="separator" style="clear: both; text-align: center;"><iframe allowfullscreen='allowfullscreen' webkitallowfullscreen='webkitallowfullscreen' mozallowfullscreen='mozallowfullscreen' width='452' height='376' src='https://www.blogger.com/video.g?token=AD6v5dzqzOu7v0P4oMup7xUzTkmSGcnipPUYkCYHnLFUf9N5e18q_xhmZZPFfsj2G0rYErx__M3PlZmBSHlZTix38w' class='b-hbp-video b-uploaded' frameborder='0'></iframe></div><p><br /></p><div>The video file is available for <a href="https://www.dropbox.com/scl/fo/udbwkkf68ppth0w1p6l1g/h?dl=0&rlkey=iesbpedok9pgvoesogck8q7la" target="_blank"><b>download</b></a>. The video presents an analysis of a relatively mobile (slightly adsorbed and retarded) chemical, is for illustrative purposes only, and does not represent McLane Environmental’s analysis of, nor conclusions regarding, any particular real site or plume.</div><div><br /></div><div><sup>1</sup> Baca, E. 1999. On the Misuse of the Simplest Transport Model. Groundwater v 37, no 4, Jul-Aug 1999.</div>flexAEMhttp://www.blogger.com/profile/06315034871207029515noreply@blogger.com0tag:blogger.com,1999:blog-2626672773765534936.post-76739417713380298582023-06-15T09:23:00.001-07:002023-06-15T09:23:12.845-07:00TS-CHEM Example Applications – Natural Source Flushing with MNA<p> Monitored Natural Attenuation (MNA) is a remediation method that relies on natural processes to decrease contamination in the soil or groundwater. It is a popular method of remediation since it tends to involve less equipment and labor and therefore, less cleanup costs. </p><p>Scientists typically monitor the contamination at a site to ensure that it is attenuating properly and within a reasonable time period. According to New Jersey’s MNA guidance, the applicability of MNA must be demonstrated by lines of evidence directly or indirectly indicate that natural attenuation processes are occurring. With TS-CHEM, it is simple to establish a clear line of evidence that demonstrates natural attenuation is occurring at your site.</p><p>This blog post will cover the second Example Application in the TS-CHEM Example Application series: Natural Source Flushing with MNA. To follow along and review the model files, you can download this example application <a href="https://transportstudio.com/example-applications.php?utm_source=blog&utm_medium=post&utm_campaign=ex_application_2" target="_blank">HERE</a>.</p><p><b>Overview</b></p><p>In this scenario, there has been a gasoline release from the dispenser island at a service station. While the leak is repaired shortly after the release, regulators and residents are worried about the release of benzene to the ground considering a residential development is located 1,200 feet to the east where shallow domestic wells are located. An initial on-site investigation reveals the following information:</p><div><div>•<span style="white-space: pre;"> </span>Aquifer material = medium sand; some gravel; little silt</div><div>•<span style="white-space: pre;"> </span>Hydraulic gradient to the east = 0.003 ft/ft</div><div>•<span style="white-space: pre;"> </span>Source area (MW-4) benzene concentration = 3,000 ug/L</div></div><div><br /></div><div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEjgBb7jc9RG4jviKePr0ByA7YVYAmE3UK5ikJmSfJG2fGj0QfL73v1xKf4TbhOIK2vM3LxUMT4WM8ZbAi4kxMcPyncFfZsqAc-asNpU1xDgjVTn8WNOHcHnllhoblCvK47ROYm4kU8x_mQAFjK8zvyRXL4fHRcXdkRAlcGjXZOysib4lxD7DyB84sl9dQ" style="margin-left: auto; margin-right: auto;"><img alt="" data-original-height="539" data-original-width="975" height="354" src="https://blogger.googleusercontent.com/img/a/AVvXsEjgBb7jc9RG4jviKePr0ByA7YVYAmE3UK5ikJmSfJG2fGj0QfL73v1xKf4TbhOIK2vM3LxUMT4WM8ZbAi4kxMcPyncFfZsqAc-asNpU1xDgjVTn8WNOHcHnllhoblCvK47ROYm4kU8x_mQAFjK8zvyRXL4fHRcXdkRAlcGjXZOysib4lxD7DyB84sl9dQ=w640-h354" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Figure 1. Site map showing the distance from the benzene source at the dispenser island to the residential area.</td></tr></tbody></table><div class="separator" style="clear: both; text-align: center;"><br /></div><div class="separator" style="clear: both; text-align: left;"><div class="separator" style="clear: both;">Concerned by cleanup costs, the responsible party would prefer to remediate the contaminated area using MNA if possible. For MNA to be applicable, the responsible party needs to demonstrate that benzene is being flushed away sufficiently so as not to impact the domestic wells 1,200 feet away. For this example project, the benzene plume boundary is set to 5 ug/L since the USEPA drinking water standard for benzene is 5 ug/L.</div><div class="separator" style="clear: both;"><br /></div><div class="separator" style="clear: both;"><b>Setting Up the Model</b></div><div class="separator" style="clear: both;"><br /></div><div class="separator" style="clear: both;">Since the leak from the dispenser island has been repaired, there is no constant source of contamination. Because of this, BIOSCREEN-AT is a good model solution for this analysis because its vertical patch source (in a semi-infinite aquifer bounded at the water table) represents an exponentially decaying source concentration. This model solution will allow you to see changes in maximum plume extent from an early phase of growth, and then through subsequent plume decrease as the sources flushes away. In TS-CHEM, the following model parameters should be set:</div><div class="separator" style="clear: both;"><br /></div><div class="separator" style="clear: both;">•<span style="white-space: pre;"> </span>Hydraulic gradient = 0.003 ft/t</div><div class="separator" style="clear: both;">•<span style="white-space: pre;"> </span>Hydraulic conductivity = 60 ft/d</div><div class="separator" style="clear: both;">•<span style="white-space: pre;"> </span>Effective porosity = 0.25</div><div class="separator" style="clear: both;">•<span style="white-space: pre;"> </span>Source width = 10 ft</div><div class="separator" style="clear: both;">•<span style="white-space: pre;"> </span>Source depth = 2 ft</div><div class="separator" style="clear: both;">•<span style="white-space: pre;"> </span>Initial Benzene source concentration = 3,000 ug/L</div><div class="separator" style="clear: both;">•<span style="white-space: pre;"> </span>Initial estimate of source flushing half life = 4 years</div><div class="separator" style="clear: both;"><br /></div><div class="separator" style="clear: both;"><b>Analysis 1: Examining Source Decrease Through Flushing</b></div><div class="separator" style="clear: both;"><br /></div><div class="separator" style="clear: both;">First, model observation points should be set downgradient from the dispenser at 100 ft (MW-1), 600 ft (mid-way to the neighborhood), and 1000 ft (approaching the neighborhood).</div><div><br /></div><div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEgL0oma6fvZ_wuR8MMIGnthP6tVxtShpXlj-0sCW6AYmRSSjjKFV5UgclNt1jwMjW8osrfBQH0rndcaloi93Qj3g5zi46KeVQCUuUXPwZngQlpGrYj1NRDT13TYSID0xaD2O49QMkfL7z1MfgVB4skPmDPIMoRZAR3Ij9H8gHpM3gPHRIdMWe4IdV1xmA" style="margin-left: auto; margin-right: auto;"><img alt="" data-original-height="537" data-original-width="975" height="352" src="https://blogger.googleusercontent.com/img/a/AVvXsEgL0oma6fvZ_wuR8MMIGnthP6tVxtShpXlj-0sCW6AYmRSSjjKFV5UgclNt1jwMjW8osrfBQH0rndcaloi93Qj3g5zi46KeVQCUuUXPwZngQlpGrYj1NRDT13TYSID0xaD2O49QMkfL7z1MfgVB4skPmDPIMoRZAR3Ij9H8gHpM3gPHRIdMWe4IdV1xmA=w640-h352" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Figure 2. Site map showing model observation points located in between the dispenser island and the residential area.</td></tr></tbody></table><div><br /></div>These observation points should give insight into the levels of benzene at these locations over time and whether the benzene plume is decaying at a sufficient rate. After running the model for ten years, the C v t plots reveal that the plume reaches a peak around 1.5 years on the station property but continues to advance towards the neighborhood. The observation points located farther downgradient from the source show the arrival and growth (increasing concentrations) of the plume until the reduction of the source causes concentrations to decline in these areas.</div><div><br /></div><div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEjzLJ_VsVo0eAupn5I9hNK9WsixwyXtGEqP4-9g9eqOKSudGrS3HHk8iUngNmcRnqQdHNrOUhpQMexnIB-xUqu92Z1FK7IiNsbQFZj5qkWHHBk2u7rpi_vpPCn31Q2djjWmHSu03lIw2DIpQJPOtmzkBH0q-fcbMbyrob6WDzJHbcCGXdnlAz3mlGKXpw" style="margin-left: auto; margin-right: auto;"><img alt="" data-original-height="575" data-original-width="975" height="378" src="https://blogger.googleusercontent.com/img/a/AVvXsEjzLJ_VsVo0eAupn5I9hNK9WsixwyXtGEqP4-9g9eqOKSudGrS3HHk8iUngNmcRnqQdHNrOUhpQMexnIB-xUqu92Z1FK7IiNsbQFZj5qkWHHBk2u7rpi_vpPCn31Q2djjWmHSu03lIw2DIpQJPOtmzkBH0q-fcbMbyrob6WDzJHbcCGXdnlAz3mlGKXpw=w640-h378" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Figure 3. The C v t chart in TS-CHEM displaying benzene concentrations near the source at MW-1 (dark blue), 600 ft from the source (aqua), and 1000 ft from the source (red).</td></tr></tbody></table><br />The contour plot shows that the plume reaches its maximum extent of about 875 feet after 7 years and does not extend into the residential development. The calculated plume at the 7-year time point encompasses an area of 88,350 ft<sup>2</sup>.</div><div><br /></div><div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEgOFtv225OyiCvigUwVvegWOXkd_sICc5i8QFYnSvSfYmhoE4aKq3py53vPezAa8dGE-obHsDpJTRQdFUpqmotxTAebmdacWactdaCF3fEIH74z8MCvfgG4Hhpq2VOUMBmTCYo5tpgkMB2HVQUjnpdSFQK2jJC4nc_n66JkrXaK2fwUQnsn38a9bfjQNg" style="margin-left: auto; margin-right: auto;"><img alt="" data-original-height="571" data-original-width="975" height="374" src="https://blogger.googleusercontent.com/img/a/AVvXsEgOFtv225OyiCvigUwVvegWOXkd_sICc5i8QFYnSvSfYmhoE4aKq3py53vPezAa8dGE-obHsDpJTRQdFUpqmotxTAebmdacWactdaCF3fEIH74z8MCvfgG4Hhpq2VOUMBmTCYo5tpgkMB2HVQUjnpdSFQK2jJC4nc_n66JkrXaK2fwUQnsn38a9bfjQNg=w640-h374" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Figure 4. TS-CHEM's contour chart indicates that the maximum plume extent (bound at 5 ug/L) does not reach the residential area.</td></tr></tbody></table><br /></div></div>The contour plot set to year 10 shows that the extent of the benzene plume shrinks by about 150 feet. The plume will continue to shrink slowly over many years until it decreases below the 5 ug/L standard. Due to this slow rate of decay, a decision may be made to either move to evaluating an active remedy scenario in which the source is removed, or possibly to evaluate a scenario with a more rapid rate of source depletion. That source depletion Analysis 2 is presented below.<br /><br /></div><div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEhYg5PJ5hEXy8fXMl12mEmeIVUnhAyHg9b_h9N79ydusqDtmJ72H_XOZ-SJa6z84fgapaG7LyKOfPLqUC5_aclOh-w2gPCSI7UOuufNlZ9oCz3H3DlpiPNac0fGp0tQ1mT9VN_NHm1mDgE0wV-EAziu74hOtPJCvN9V8sb5xlQ0KT1C_kjbjucgkUk-zg" style="margin-left: auto; margin-right: auto;"><img alt="" data-original-height="572" data-original-width="975" height="376" src="https://blogger.googleusercontent.com/img/a/AVvXsEhYg5PJ5hEXy8fXMl12mEmeIVUnhAyHg9b_h9N79ydusqDtmJ72H_XOZ-SJa6z84fgapaG7LyKOfPLqUC5_aclOh-w2gPCSI7UOuufNlZ9oCz3H3DlpiPNac0fGp0tQ1mT9VN_NHm1mDgE0wV-EAziu74hOtPJCvN9V8sb5xlQ0KT1C_kjbjucgkUk-zg=w640-h376" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Figure 5. TS-CHEM's contour chart showing a reduction in plume extent from year 7 to year 10.</td></tr></tbody></table><br /></div><div><div><b>Analysis 2: Examining a Higher Source Degradation Rate</b></div><div><br /></div><div>Let’s say that the responsible party continues to investigate the source area of the contamination and develops information that supports a Conceptual Site Model in which the source is depleting more rapidly. Instead of the 4-year half-life employed in the previous analysis, let’s change the source decay rate to a two year half-life, and observe the effects. After running the model with this new degradation rate, the C v t plot shows a faster depletion of benzene overall as well as a faster concentration decline.</div></div><div><br /></div><div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEi3DbI3-5YnsmFlICNUA10HArAHgz_PYPDp7QVNklaWuzRYP-0vrbb3h--cMeUmeCett0yOVuShqwm3ve9nH7RPzQ_xl2X4Cde8SpgobNUg5WBRsu1JN2rLA9K9WU9xZUbMNA-G9R5oeyYHl4WNJMkMyv8ecsJeDfJWE8xXggFhAWbfXbIGSExGh3Cn1g" style="margin-left: auto; margin-right: auto;"><img alt="" data-original-height="570" data-original-width="975" height="374" src="https://blogger.googleusercontent.com/img/a/AVvXsEi3DbI3-5YnsmFlICNUA10HArAHgz_PYPDp7QVNklaWuzRYP-0vrbb3h--cMeUmeCett0yOVuShqwm3ve9nH7RPzQ_xl2X4Cde8SpgobNUg5WBRsu1JN2rLA9K9WU9xZUbMNA-G9R5oeyYHl4WNJMkMyv8ecsJeDfJWE8xXggFhAWbfXbIGSExGh3Cn1g=w640-h374" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Figure 6. The C v t chart in TS-CHEM displaying benzene concentrations at the three set observation points.</td></tr></tbody></table><div class="separator" style="clear: both; text-align: center;"><br /></div>The contour chart shows that after 6 years, the benzene plume (with a boundary of 5 ug/L) extends about 810 feet with an area of 68,150 ft2 before receding, which is 22% smaller than the maximum plume extent in the previous analysis. By year 10, the plume boundary recedes to about 220 feet.</div><div><br /></div><div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEhzKxhlJPKFaV1FAJAg773HUF2Plytxe13vlDKsYQ82pxGUeDvy_BQ6_BfWybnDJLCNmYBjv8TfVLyrHwo5DnbKK7dGgY6aLg7JM4IBTZtxBp07IIq8M2oAnX_YfoUaE-WNTHYZtvgfIq9MrOr-aPhH9ttBXEUoljzUgEmeQP4zdLrH7VfWpZo29tlyRw" style="margin-left: auto; margin-right: auto;"><img alt="" data-original-height="573" data-original-width="975" height="376" src="https://blogger.googleusercontent.com/img/a/AVvXsEhzKxhlJPKFaV1FAJAg773HUF2Plytxe13vlDKsYQ82pxGUeDvy_BQ6_BfWybnDJLCNmYBjv8TfVLyrHwo5DnbKK7dGgY6aLg7JM4IBTZtxBp07IIq8M2oAnX_YfoUaE-WNTHYZtvgfIq9MrOr-aPhH9ttBXEUoljzUgEmeQP4zdLrH7VfWpZo29tlyRw=w640-h376" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Figure 7. The contour chart in TS-CHEM set to year 6 highlighting its shorter plume extent compared to the previous analysis.</td></tr></tbody></table><br /></div><div><div>The smaller plume area and quick recession of the plume may support the case for MNA at this site. Further source zone characterization may be needed to support the use of the faster degradation rate, however.</div><div><br /></div><div><b>Analysis 3: Examining A Higher Source and Plume Degradation Rate</b></div><div><br /></div><div>Oftentimes, regulatory agencies prescribe longer half-lives for constituents for the purposes of risk evaluations. In many cases, however, half-lives of contaminants like benzene are shorter than the default degradation rates typically prescribed by regulatory agencies. In this analysis, let’s increase the degradation rate of the plume (in addition to the increased degradation rate of the source in the last analysis) to observe the contamination extent in the case of a rapidly depleting source and plume. Instead of a 2-year half-life, let’s change the benzene degradation rate to a 0.5 year half-life.</div><div>The C v t plot shows that the maximum concentration observed at MW-1 is less than the maximum concentrations observed in the previous two analyses. Also, the plume decays before reaching the next two observation points at 600 and 1000 feet.</div></div><div><br /></div><div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEj3p39AJH3kbILpU5SsGkwY0Y4QZIi2WehJuh7P79YHp9kEhaWv-vpkREKBdg_drvb9fwng7PV9Jgfb3NNm9DeHQNcKiuYFQ2-jhNbtlGQFephhsiCKdQjGjfP3KiXS_R1yv2zzr6PIFcWmewX0Ah5ZHKJBFpwD4xBSVfLYbgv6JRdh-KDChcBpTjf2ww" style="margin-left: auto; margin-right: auto;"><img alt="" data-original-height="575" data-original-width="975" height="378" src="https://blogger.googleusercontent.com/img/a/AVvXsEj3p39AJH3kbILpU5SsGkwY0Y4QZIi2WehJuh7P79YHp9kEhaWv-vpkREKBdg_drvb9fwng7PV9Jgfb3NNm9DeHQNcKiuYFQ2-jhNbtlGQFephhsiCKdQjGjfP3KiXS_R1yv2zzr6PIFcWmewX0Ah5ZHKJBFpwD4xBSVfLYbgv6JRdh-KDChcBpTjf2ww=w640-h378" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Figure 8. The TS-CHEM C v t chart showing benzene concentrations in the three set observation points. In this analysis, benzene isn't detected at the latter two observation points.</td></tr></tbody></table><div class="separator" style="clear: both; text-align: center;"><br /></div>The benzene plume extends to about 350 feet after 2 years before quickly shrinking in areal extent. The plume area at year 2 is 26,150 ft<sup>2</sup>, which is 61% smaller than the maximum plume extent in the first analysis. After year 10, the plume only extends to about 110 feet due to the groundwater flushing of the source, as well as the higher degradation occurring within the plume itself.</div><div><br /></div><div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEjq255HnX9ctU7ufVN9Fl0FmYIVtdwStyky6-frEQCoVyhn37MtLJke1w6b6ZsgvQVz8cEtEDHM9Th1R0N6ntX-bf7ySnxXKlvHnWSd4l0koc7DOsCqFBRYvNSHQnd30m5b2FHw54k6dELOeCMOWjiwLPb2105bhhTAoPB0wXDFWJdwpwOkuZLxhWX1bQ" style="margin-left: auto; margin-right: auto;"><img alt="" data-original-height="574" data-original-width="975" height="376" src="https://blogger.googleusercontent.com/img/a/AVvXsEjq255HnX9ctU7ufVN9Fl0FmYIVtdwStyky6-frEQCoVyhn37MtLJke1w6b6ZsgvQVz8cEtEDHM9Th1R0N6ntX-bf7ySnxXKlvHnWSd4l0koc7DOsCqFBRYvNSHQnd30m5b2FHw54k6dELOeCMOWjiwLPb2105bhhTAoPB0wXDFWJdwpwOkuZLxhWX1bQ=w640-h376" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Figure 9. A greatly reduced benzene plume seen in TS-CHEM's contour chart following the increase of plume and source degradation rates.</td></tr></tbody></table><br /><div>This analysis - - especially using the more rapid benzene plume degradation rate - - shows that MNA could be a good potential remedial option for this site if acceptable information can be generated to support the degradation rates of the source and the plume. </div><div><br /></div><div><b>Conclusion</b></div><div><br /></div><div>MNA is an attractive remedial option for parties looking to reduce cleanup costs, however, it must first be demonstrated that your site is a viable candidate for MNA per state and federal guidance. This often includes using data-driven solutions to form lines of evidence as to why your site is suitable for MNA. TS-CHEM provides a simple tool to evaluate the growth and decay of a contaminant plume, which allows for the evaluation of potential impacts to receptor locations downgradient from the source in the case the source concentration decreases through time due to flushing. This type of analysis can help determine a site’s suitability for MNA as a remedy.</div></div><div><br /></div><div><br /></div>flexAEMhttp://www.blogger.com/profile/06315034871207029515noreply@blogger.com0tag:blogger.com,1999:blog-2626672773765534936.post-80765922076181046302023-05-25T06:16:00.001-07:002023-05-25T06:16:46.835-07:00Monitoring Well Placement and Plume Behavior<p> </p><p class="MsoNormal" style="margin-bottom: 0in;">Groundwater monitoring wells are
often placed in, around, and downgradient from a dissolved contaminant plume
for a variety of purposes including:</p><p class="MsoNormal" style="margin-bottom: 0in;"></p><ul style="text-align: left;"><li><span style="text-indent: -0.25in;">Monitoring plume dynamics (concentration
changes) in different areas of the plume following a chemical release as the
plume grows</span></li><li>Bounding the plume in the horizontal and
vertical for regulatory compliance and remedy planning purposes</li><li>Evaluating plume stability as a criterion for
considering a Monitored Natural Attenuation (MNA) remedy</li><li>Projecting plume reduction over time as the
result of a source remediation and/or MNA remedy</li><li>Proper placement of downgradient sentinel wells
to protect potential receptors</li></ul><p></p><p class="MsoListParagraphCxSpLast" style="margin-bottom: 0in; mso-add-space: auto; mso-list: l0 level1 lfo1; text-indent: -0.25in;"><o:p></o:p></p>
<p class="MsoNormal" style="margin-bottom: 0in;"><o:p> </o:p></p>
<p class="MsoNormal" style="margin-bottom: 0in;">Planning the layout of a
groundwater network is highly source and aquifer specific, with well location
distances and anticipated contaminant arrival times being dependent on
groundwater velocity and source concentration. Placement and interpretation of
concentration patterns are also related to the source type; i.e. whether the
source is constant, slowly declining (flushing), or suddenly removed
(excavation).<o:p></o:p></p>
<p class="MsoNormal" style="margin-bottom: 0in;"><o:p> </o:p></p>
<p class="MsoNormal" style="margin-bottom: 0in;">Simple analytical contaminant fate
and transport modeling can be very helpful in identifying optimal locations for
monitoring wells, and in interpreting sampling results obtained from those
wells. The following examples illustrate the application of TS-CHEM for the
design and analysis of monitoring well networks for differing source and
aquifer conditions.<o:p></o:p></p>
<p class="MsoNormal" style="margin-bottom: 0in;"><o:p> </o:p></p>
<p class="MsoNormal" style="margin-bottom: 0in;"><b>Example 1 – Constant Source: Plume
Growth and Stabilization<o:p></o:p></b></p>
<p class="MsoNormal" style="margin-bottom: 0in;"><o:p> </o:p></p>
<p class="MsoNormal" style="margin-bottom: 0in;">For the case where a chemical
spill creates a continuing constant concentration source to groundwater, a
dissolved contaminant plume will form, grow, and eventually stabilize (stop
growing) (see time series in Figure 1). Monitoring wells placed down the axis
of the plume can show this progression as concentrations rise through time and
then sequentially level off at each downgradient location (Fig 2 and Fig 3).</p><p class="MsoNormal" style="margin-bottom: 0in;"></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEhE39k1d1NljM-0K1q2_EmMlGAnBB12h3_kfIFTaT7mJ9mwO8fsREis21EugYZK-pzzSSBHLYqGX52GVlS2BUP1_8JUwrOhkU0-R40DPDpgqp1SorFPSuS1kmRyMqjXvDcXW_cHd--2yLwRYgtroeWKK6febWnKK10HvKmFYdIjuqdOi52O0h6iXGmVcg" style="margin-left: 1em; margin-right: 1em;"><img alt="" data-original-height="477" data-original-width="975" height="314" src="https://blogger.googleusercontent.com/img/a/AVvXsEhE39k1d1NljM-0K1q2_EmMlGAnBB12h3_kfIFTaT7mJ9mwO8fsREis21EugYZK-pzzSSBHLYqGX52GVlS2BUP1_8JUwrOhkU0-R40DPDpgqp1SorFPSuS1kmRyMqjXvDcXW_cHd--2yLwRYgtroeWKK6febWnKK10HvKmFYdIjuqdOi52O0h6iXGmVcg=w640-h314" width="640" /></a></div><br /><p></p><p class="MsoNormal" style="margin-bottom: 0in;"><span style="font-size: 13.3333px;">F</span><span style="font-size: 10pt;">igure 1. Plume growth and stabilization caused by the slow
constant dissolution of a vinyl chloride source. Monitoring wells are located
at the following distances from the source: MW-1</span><span style="font-size: 10pt;"> </span><span style="font-size: 10pt;">400 ft; MW-2</span><span style="font-size: 10pt;">
</span><span style="font-size: 10pt;">600 ft; MW-3</span><span style="font-size: 10pt;"> </span><span style="font-size: 10pt;">700 ft; MW-4</span><span style="font-size: 10pt;"> </span><span style="font-size: 10pt;">875 ft. The placement of MW-4 coincides with
the farthest downgradient extent of the plume after it has stabilized about 7.5
years after the initial release.</span></p>
<p class="MsoNormal" style="margin-bottom: 0in;"><o:p> </o:p></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEhB0SChoaoBbppjj8ThLuexSz03VIxILexgcSgljv7y6qA99o6m_kQLbjVuwHuAR5GpIYhpvAA84xuQDGs8iCRUXqwHfhKDdETr8WWgJzAcji28mBfjBN-Rrpi2EnptXSM7Ud4ENh-E8QgrJZyIuXTJyeh4MERditc1oB45JNZAC0ydFKQOxZIKW49y3A" style="margin-left: 1em; margin-right: 1em;"><img alt="" data-original-height="600" data-original-width="975" height="394" src="https://blogger.googleusercontent.com/img/a/AVvXsEhB0SChoaoBbppjj8ThLuexSz03VIxILexgcSgljv7y6qA99o6m_kQLbjVuwHuAR5GpIYhpvAA84xuQDGs8iCRUXqwHfhKDdETr8WWgJzAcji28mBfjBN-Rrpi2EnptXSM7Ud4ENh-E8QgrJZyIuXTJyeh4MERditc1oB45JNZAC0ydFKQOxZIKW49y3A=w640-h394" width="640" /></a></div><br /><p></p>
<p class="MsoNormal" style="margin-bottom: 0in;"><span style="mso-no-proof: yes;"><v:shape alt="A picture containing text, line, plot, diagram
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</v:imagedata></v:shape></span><o:p></o:p></p>
<p class="MsoNormal" style="margin-bottom: 0in;"><span style="font-size: 10pt; line-height: 107%;">Figure 2. The spreading plume reaches each downgradient
monitoring well in turn, causing the vinyl chloride concentration at that
location to rise. After some period of time following first impact at a well
location, the plume stabilizes in that area as indicated by the leveling off of
monitoring well concentration.<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-bottom: 0in;"><o:p> </o:p></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEiyix5-PrmVgwXQVbVVdK71xOjthlhU5qD2JuWnNMhfdYgedUu5Eok09WuykCqooV5mp9esq0aRGGWNyo6sj2AHoumKp5t0qqs2hm8VM-2R2J7aEJC4niUOkQF6jF6-Kou6fPMOIhBHCAA2iYIM75o6yGKTWrgj4w0GCouG_gWP5f15khXNsw7tuJyBLA" style="margin-left: 1em; margin-right: 1em;"><img alt="" data-original-height="600" data-original-width="975" height="394" src="https://blogger.googleusercontent.com/img/a/AVvXsEiyix5-PrmVgwXQVbVVdK71xOjthlhU5qD2JuWnNMhfdYgedUu5Eok09WuykCqooV5mp9esq0aRGGWNyo6sj2AHoumKp5t0qqs2hm8VM-2R2J7aEJC4niUOkQF6jF6-Kou6fPMOIhBHCAA2iYIM75o6yGKTWrgj4w0GCouG_gWP5f15khXNsw7tuJyBLA=w640-h394" width="640" /></a></div><br /><p></p>
<p class="MsoNormal" style="margin-bottom: 0in;"><span style="mso-no-proof: yes;"><v:shape alt="A picture containing text, line, plot, diagram
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</v:imagedata></v:shape></span><o:p></o:p></p>
<p class="MsoNormal" style="margin-bottom: 0in;"><span style="font-size: 10pt; line-height: 107%;">Figure 3. Zooming in on the lower concentrations measured at
MW-3 and MW-4 shows that these downgradient wells exhibit the same
concentration versus time pattern as the wells in the central area of the
plume.<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-bottom: 0in;"><o:p> </o:p></p>
<p class="MsoNormal" style="margin-bottom: 0in;"><b>Example 2 – Instantaneous
Source: Plume Drift and Dissipation<o:p></o:p></b></p>
<p class="MsoNormal" style="margin-bottom: 0in;"><o:p> </o:p></p>
<p class="MsoNormal" style="margin-bottom: 0in;">For the case where a small chemical
spill enters groundwater and dissolves - - creating an initial slug source in a
small localized area - - a dissolved contaminant plume will leave that area and
drift downgradient with groundwater seepage, spreading and dissipating as it
does so (see time series in Figure 4). Monitoring wells placed down the axis of
the plume can show this progressive arrival at, passing through, and leaving
each monitoring well area (Fig 5 and Fig 6).<o:p></o:p></p>
<p class="MsoNormal" style="margin-bottom: 0in;"><o:p> </o:p></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEhf0KQAC5pjun3gK5BlB1fF7dF2OuefbT7IX0caxOxGTbxDCxfTscQ6ydJDp7H9MVbCtDCwHPaazg3pzzRusUoGGm_l9i9Vjfp97ZG9iGFVwGBHLogvQdYQCfW1LR4WZ77OzJSpUxtG9_sgvFSAeFSU_txPYoYCtf-WNTmx_IcQg6bYL0L0AS2hh4b8XQ" style="margin-left: 1em; margin-right: 1em;"><img alt="" data-original-height="477" data-original-width="975" height="314" src="https://blogger.googleusercontent.com/img/a/AVvXsEhf0KQAC5pjun3gK5BlB1fF7dF2OuefbT7IX0caxOxGTbxDCxfTscQ6ydJDp7H9MVbCtDCwHPaazg3pzzRusUoGGm_l9i9Vjfp97ZG9iGFVwGBHLogvQdYQCfW1LR4WZ77OzJSpUxtG9_sgvFSAeFSU_txPYoYCtf-WNTmx_IcQg6bYL0L0AS2hh4b8XQ=w640-h314" width="640" /></a></div><br /><p></p>
<p class="MsoNormal" style="margin-bottom: 0in;"><span style="font-size: 10pt; line-height: 107%;">Figure 4. Plume behavior resulting from initial dissolution
of a vinyl chloride source, with subsequent downgradient drift. Monitoring
wells are located at the following distances from the source: MW-1<span style="mso-spacerun: yes;"> </span>400 ft; MW-2<span style="mso-spacerun: yes;">
</span>600 ft; MW-3<span style="mso-spacerun: yes;"> </span>700 ft; MW-4<span style="mso-spacerun: yes;"> </span>875 ft. The plume initially expands as it
drifts, but attenuation (dispersion and degradation) gradually reduce the plume
concentrations and plume area, and eventually cause it to disappear.<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-bottom: 0in;"><o:p> </o:p></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEi-xAeUSIRwt9dPIAKWxogocFhhWDsoZZOp5ySiqZNHCsDEbdce9LFEPIQLZn1eiTs81u5nCvGXJU9LHJlX6ojdoLuC38E93KzhTQH-J5lMddw_STf4gpUg_i3-fAtzslHbcXwo92uYnR4KAdQpERp_S8yymgByBswkRjRB49WI2cCC2loPbYVtPDKf3A" style="margin-left: 1em; margin-right: 1em;"><img alt="" data-original-height="600" data-original-width="975" height="394" src="https://blogger.googleusercontent.com/img/a/AVvXsEi-xAeUSIRwt9dPIAKWxogocFhhWDsoZZOp5ySiqZNHCsDEbdce9LFEPIQLZn1eiTs81u5nCvGXJU9LHJlX6ojdoLuC38E93KzhTQH-J5lMddw_STf4gpUg_i3-fAtzslHbcXwo92uYnR4KAdQpERp_S8yymgByBswkRjRB49WI2cCC2loPbYVtPDKf3A=w640-h394" width="640" /></a></div><br /><p></p>
<p class="MsoNormal" style="margin-bottom: 0in;"><span style="font-size: 10pt; line-height: 107%;">Figure 5. The drifting and spreading plume reaches each
downgradient monitoring well in turn, causing the vinyl chloride concentration
at that location to rise, peak, and then decline. Notice that the velocity of
the plume peak does not match the groundwater Darcy velocity, nor the retarded
groundwater Darcy velocity.<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-bottom: 0in;"><o:p> </o:p></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEjtJqQnp1bQtySOv5j4DjQ2-6DnH2Z9grEcQ6nr_IRX67G4h9nye6fIrn7LD4fnqhgUta6tmWM91m1BQ3FqGvP66O79SHJB672fq6TUwrPXNvYW7gZtzmxlctJP2pgGskQrq7J7K2kwQFPAsK7W1ICEZ9uQdVHjI78xXnBG11-tQns1NmXyzMj1ZrL2zg" style="margin-left: 1em; margin-right: 1em;"><img alt="" data-original-height="600" data-original-width="975" height="394" src="https://blogger.googleusercontent.com/img/a/AVvXsEjtJqQnp1bQtySOv5j4DjQ2-6DnH2Z9grEcQ6nr_IRX67G4h9nye6fIrn7LD4fnqhgUta6tmWM91m1BQ3FqGvP66O79SHJB672fq6TUwrPXNvYW7gZtzmxlctJP2pgGskQrq7J7K2kwQFPAsK7W1ICEZ9uQdVHjI78xXnBG11-tQns1NmXyzMj1ZrL2zg=w640-h394" width="640" /></a></div><br /><p></p>
<p class="MsoNormal" style="margin-bottom: 0in;"><span style="mso-no-proof: yes;"><v:shape alt="A picture containing text, line, plot, diagram
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</v:imagedata></v:shape></span><o:p></o:p></p>
<p class="MsoNormal" style="margin-bottom: 0in;"><span style="font-size: 10pt; line-height: 107%;">Figure 6. Zooming in on the lower concentrations measured at
MW-3 and MW-4 shows that these downgradient wells exhibit the same
concentration versus time pattern as the wells in the central area of the
plume.<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-bottom: 0in;"><o:p> </o:p></p>
<p class="MsoNormal" style="margin-bottom: 0in;">For the ideal case (often
described in textbooks) the downgradient movement of the plume peak (even as
that peak concentration declines with time) would occur at the same rate as the
calculated Darcy’s Law groundwater pore velocity, which is 146 ft/yr for the
model depicted above. If the chemical of interest were affected by adsorption
and retardation, one might expect the plume peak to move at the rate of the
groundwater velocity divided by the retardation rate. For this vinyl chloride model,
that rate is 146 ft/yr / 1.113 = 131.1 ft/yr.<o:p></o:p></p>
<p class="MsoNormal" style="margin-bottom: 0in;"><o:p> </o:p></p>
<p class="MsoNormal" style="margin-bottom: 0in;">Instead, the plots above
demonstrate that the plume peak is moves downgradient from the source at a <u>faster
apparent rate</u> of approximately 155 ft/yr - - almost 20 % faster than the
retarded groundwater velocity; and faster even than the average groundwater
linear pore velocity of 146 ft/yr. This is caused by the nonlinear interaction
of all of the processes acting on the vinyl chloride plume: groundwater seepage
velocity, retardation, dispersion, and degradation. Thus, a model can be very
useful in developing a more accurate estimate of the rate of movement of a
detached (from the source) contaminant plume than simple velocity calculations
would provide.<o:p></o:p></p>
<p class="MsoNormal" style="margin-bottom: 0in;"><o:p> </o:p></p>
<p class="MsoNormal" style="margin-bottom: 0in;">To learn more about TS-CHEM and
how it can be used to assist with the estimation of the extent and movement of
contaminant plumes, or to download a<span face=""Arial",sans-serif" style="background: white; color: black; font-size: 11.5pt; line-height: 107%;"> </span><a href="https://transportstudio.com/downloads.php" target="_blank"><span face=""Arial",sans-serif" style="background: white; color: #2b00fe; font-size: 11.5pt; line-height: 107%; text-decoration: none; text-underline: none;">FREE
DEMO</span></a><span face=""Arial",sans-serif" style="background: white; color: black; font-size: 11.5pt; line-height: 107%;"> </span>of the software, visit the<span face=""Arial",sans-serif" style="background: white; color: black; font-size: 11.5pt; line-height: 107%;"> </span><a href="https://transportstudio.com/software.php" target="_blank"><span face=""Arial",sans-serif" style="background: white; color: #265fd3; font-size: 11.5pt; line-height: 107%; text-decoration: none; text-underline: none;">TS-CHEM
Website</span></a><span face=""Arial",sans-serif" style="background: white; color: #2b00fe; font-size: 11.5pt; line-height: 107%;"> </span>today!<o:p></o:p></p>flexAEMhttp://www.blogger.com/profile/06315034871207029515noreply@blogger.com0tag:blogger.com,1999:blog-2626672773765534936.post-76096962753665149132023-05-12T12:45:00.001-07:002023-05-12T12:45:32.724-07:00TS-CHEM Version 2023-1 Now Available!<p><span style="color: #3d85c6; font-family: arial;"> <b><span style="font-size: 14.0pt; line-height: 107%;">New
Features in TS-CHEM v2023-1</span></b></span></p><p><span style="font-family: arial;"><br /></span></p><p><span style="font-family: arial;">We are proud to announce the release of <span style="color: #3d85c6;"><b>TS-CHEM version
2023-1</b></span>! There are a host of new features, with key updates including:</span></p><p><span style="font-family: arial; text-indent: -0.25in;"><span style="font-feature-settings: normal; font-kerning: auto; font-optical-sizing: auto; font-size: 7pt; font-stretch: normal; font-variant-alternates: normal; font-variant-east-asian: normal; font-variant-numeric: normal; font-variation-settings: normal; line-height: normal;"><br /></span></span></p><p></p><ul style="text-align: left;"><li><span style="font-family: arial; text-indent: -0.25in;"><span style="font-feature-settings: normal; font-kerning: auto; font-optical-sizing: auto; font-size: 7pt; font-stretch: normal; font-variant-alternates: normal; font-variant-east-asian: normal; font-variant-numeric: normal; font-variation-settings: normal; line-height: normal;"> </span></span><span style="font-family: arial; text-indent: -0.25in;">A new color spectrum </span><span style="font-family: arial; text-indent: -0.25in;">control for contour charts</span></li><li><span style="font-family: arial; text-indent: -0.25in;">The addition of a plume boundary specification with contour plots using the log scale</span></li><li><span style="font-family: arial; text-indent: -0.25in;">Refined unit conversion factors for model setup parameters</span></li><li><span style="font-family: arial; text-indent: -0.25in;">An enforced QA check on the model data’s save and reload process</span></li><li><span style="font-family: arial; text-indent: -0.25in;">Minor bug fixes</span></li></ul><p></p>
<p class="MsoNormal"><span style="font-family: arial;">The new changes to contour plots allow for more flexibility
than ever when visualizing your modeled plume! A brief overview of these new
features is included below.<o:p></o:p></span></p>
<p class="MsoNormal"><b><span style="font-size: 12.0pt; line-height: 107%;"><o:p><span style="font-family: arial;"> </span></o:p></span></b></p>
<p class="MsoNormal"><b><span style="font-size: 12.0pt; line-height: 107%;"><span style="font-family: arial;"><span style="color: #ffa400;">A
COLORFUL (HALF-) LIFE</span></span></span></b></p>
<p class="MsoNormal"><span style="font-family: arial;">Contour plots in <span style="color: #3d85c6;"><b>TS-CHEM</b></span> just g</span><span style="font-family: arial;">ot more colorful! In v2023-1
a color spectrum control has been added for contour charts. This allows the
user to fine-tune their color scale with up to five colored contour intervals!</span></p><p class="MsoNormal"><o:p></o:p></p><p class="MsoNormal"><span style="font-family: arial;"><br /></span></p><p class="MsoNormal"></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgIJnoHIwkCQFvkXgyglYPolNzHhYxO51ghr-xxK3nNhrDbBr7R1_0R45qjLRdmHyoIFQ1_r4XvpEjTewLCkgi95JZhJCWMQuy3CL--QmK9InBPYKrwdiLAujQdLAZTKsFrGm3JFe4By2mCUp1-PW6cnmimsl_arqZWdmD-BiV9pGT_vLsx7WTZuNgywQ/s1477/Figure%201.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="851" data-original-width="1477" height="368" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgIJnoHIwkCQFvkXgyglYPolNzHhYxO51ghr-xxK3nNhrDbBr7R1_0R45qjLRdmHyoIFQ1_r4XvpEjTewLCkgi95JZhJCWMQuy3CL--QmK9InBPYKrwdiLAujQdLAZTKsFrGm3JFe4By2mCUp1-PW6cnmimsl_arqZWdmD-BiV9pGT_vLsx7WTZuNgywQ/w640-h368/Figure%201.png" width="640" /></a></div><p></p><p class="MsoNormal"><span style="font-family: arial;"><br /></span></p><p class="MsoNormal"><span style="font-family: arial;">In addition to allowing for custom-colored contour
intervals, if the user wants to define their concentrations as “high” or “low”,
just adjust the <b><span style="color: #ffa400;">Gradient Style</span></b> to <b><span style="color: #ffa400;">Two Colors</span></b> and refine the plot.</span></p><p class="MsoNormal"><span style="font-family: arial;"><br /></span></p><p class="MsoNormal"></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgVz-K4bVKd77WwfaL0bNR3-EdwBFf5DHA1hSOrUj0hIqkb33EHL-0dm3YXzyNVx5MjWIwxx1pf-yIbLg56zJP3rSbV78pMIVcjeH2sKYHR98BubAH6DUx_pyXRWSuO0UgRGaEBMzTfO1GjQ44xjaTi_p9SXLuVEqBnSnj-8wM04hsdIk92HllEW_rO3w/s1443/Figure%202.tif" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="855" data-original-width="1443" height="380" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgVz-K4bVKd77WwfaL0bNR3-EdwBFf5DHA1hSOrUj0hIqkb33EHL-0dm3YXzyNVx5MjWIwxx1pf-yIbLg56zJP3rSbV78pMIVcjeH2sKYHR98BubAH6DUx_pyXRWSuO0UgRGaEBMzTfO1GjQ44xjaTi_p9SXLuVEqBnSnj-8wM04hsdIk92HllEW_rO3w/w640-h380/Figure%202.tif" width="640" /></a></div><div class="separator" style="clear: both; text-align: center;"><br /></div><div class="separator" style="clear: both; text-align: center;"></div><p></p><p class="MsoNormal"><span style="font-family: arial;">The new version of <b><span style="color: #3d85c6;">TS-CHEM</span></b> can even represent a single color
in style! With the <b><span style="color: #ffa400;">One Color Transparency</span></b> option the concentrations
become more transparent the lower they get, emphasizing where the high concentrations
occur in your plume.</span><o:p></o:p></p><p class="MsoNormal"><span style="font-family: arial;"><br /></span></p><p class="MsoNormal"><o:p></o:p></p><div class="separator" style="clear: both; text-align: left;"></div><p class="MsoNormal"></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgrOCv6saaW5soF9sXWFOAdPfiRpBqtez0EDWf6ObnPN2dy4LevUHda7utw8-eHi7MBHsAVKCvkMZF-4rKENcYoxIKdhdLEpeWAQUVLFMWFaPrvyoiLHY7RQ48mJr2-rhjjeFY5w33q94GovdGVPh7RT1Mm2jz2QuTxu6IY1ZnmUYv0pEuyuMj3om5Rqw/s1477/Figure%203.tif" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="857" data-original-width="1477" height="372" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgrOCv6saaW5soF9sXWFOAdPfiRpBqtez0EDWf6ObnPN2dy4LevUHda7utw8-eHi7MBHsAVKCvkMZF-4rKENcYoxIKdhdLEpeWAQUVLFMWFaPrvyoiLHY7RQ48mJr2-rhjjeFY5w33q94GovdGVPh7RT1Mm2jz2QuTxu6IY1ZnmUYv0pEuyuMj3om5Rqw/w640-h372/Figure%203.tif" width="640" /></a></div><div class="separator" style="clear: both; text-align: center;"><br /></div><p></p><p class="MsoNormal"><o:p></o:p></p><p class="MsoNormal"><span style="font-family: arial;">Transparency is not just limited to the one-color setting,
either! As seen in the figures above, uniform transparency can be applied to
the contour plots using any of the color spectrums the user defines. This can
be especially useful when combined with the <span style="color: #ffa400;"><b>Map Overlay</b></span> feature!<o:p></o:p></span></p><p class="MsoNormal"><b><span style="font-size: 12.0pt; line-height: 107%;"><span style="color: #ffa400; font-family: arial;"><br /></span></span></b></p><p class="MsoNormal"><b><span style="font-size: 12.0pt; line-height: 107%;"><span style="color: #ffa400; font-family: arial;">PUT A
LIMIT ON YOUR LOG PLOTS</span><o:p></o:p></span></b></p><p class="MsoNormal"><span style="font-family: arial;">The logarithmic scale (“log” scale) is an important and
useful tool when visualizing contaminant plume data. It allows for large
differences in concentration to be expressed in an understandable way. For
instance, here is a contour plot of a contaminant plume with a linear scale:</span><o:p></o:p></p><p class="MsoNormal"></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgLdPsy3sU69daEMHZ8xQiw5r9e7t_cGhHLQyuhJDLKQ0C--MNtQflkH6QxU2_Aeif2ywd7-WAszbFQ8nbjyWPjR6m_KFit2IhH0LgPFh8e8LOJKZHJq19j7Zt07pThc-_Gxpt8rPqpsWc5OOuUkUZ7Tv0sdpkrF-7yIVzaMvWUjpZiYWfRACWrgWjkEw/s1483/Figure%204.tif" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="853" data-original-width="1483" height="368" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgLdPsy3sU69daEMHZ8xQiw5r9e7t_cGhHLQyuhJDLKQ0C--MNtQflkH6QxU2_Aeif2ywd7-WAszbFQ8nbjyWPjR6m_KFit2IhH0LgPFh8e8LOJKZHJq19j7Zt07pThc-_Gxpt8rPqpsWc5OOuUkUZ7Tv0sdpkrF-7yIVzaMvWUjpZiYWfRACWrgWjkEw/w640-h368/Figure%204.tif" width="640" /></a></div><p></p><p class="MsoNormal"><span style="font-family: arial;"><br /></span></p><p class="MsoNormal"><span style="font-family: arial;">We can see that our concentrations go from 100 – 1000 ug/L,
with contours every 100 feet. What if we wanted to see what was going on with
the lower concentrations less than 100 ug/L? We can either add a lot more
contours <i><b>or</b></i> use a logarithmic scale:</span><o:p></o:p></p><p class="MsoNormal"></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh-UZbhKAIbjk8sBE8mc7gVgMou5eu1DpEcgu8Kmq1UJxFdvdYjhXPipA_hOUOglB8dz6JnarhBePl1B_3JMCRbo16Q8T7OTbXZTQstxKRCuWspjH2-fSEXN4JqUvZ92iko03ZtbVqUp0Rum4bkyv8G4GPdfA71gssiQonxeJ_jXfoOnl-N9qpcLP4hAg/s1469/Figure%205.tif" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="877" data-original-width="1469" height="382" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh-UZbhKAIbjk8sBE8mc7gVgMou5eu1DpEcgu8Kmq1UJxFdvdYjhXPipA_hOUOglB8dz6JnarhBePl1B_3JMCRbo16Q8T7OTbXZTQstxKRCuWspjH2-fSEXN4JqUvZ92iko03ZtbVqUp0Rum4bkyv8G4GPdfA71gssiQonxeJ_jXfoOnl-N9qpcLP4hAg/w640-h382/Figure%205.tif" width="640" /></a></div><br /><p></p><p class="MsoNormal"><span style="font-family: arial;">We can now easily see our concentrations ranging from 1 to
1000 ug/L with only 10 contour lines. And, in <b><span style="color: #3d85c6;">TS-CHEM v2023-1</span></b>, we can now add a
boundary to this log scale plot. For example, we are interested in what the
plume looks like between 10 and 1000 ug/L. We can set a plume boundary equal to
10 ug/L and update our plot to reflect this new data range:</span><o:p></o:p></p><p class="MsoNormal"></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhbakq8RsdED5kKjGC2RjDPmn6QLBaVlBXUw_DcY3PZki6_imKmpl3mWeQ9j2tRRXXImSTEAsvPO3dOq9G3fRYbhZF2p2l1efUHQg-kLYX4k6qYe2exmXrKPKN1_60w5Eq3njVeL_CWAnB1l_S1gjMMCFb85isKIKD5wlOmMGKEfMNKArIpN0HwjBC06Q/s1477/Figure%206.tif" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="851" data-original-width="1477" height="368" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhbakq8RsdED5kKjGC2RjDPmn6QLBaVlBXUw_DcY3PZki6_imKmpl3mWeQ9j2tRRXXImSTEAsvPO3dOq9G3fRYbhZF2p2l1efUHQg-kLYX4k6qYe2exmXrKPKN1_60w5Eq3njVeL_CWAnB1l_S1gjMMCFb85isKIKD5wlOmMGKEfMNKArIpN0HwjBC06Q/w640-h368/Figure%206.tif" width="640" /></a></div><p></p><p class="MsoNormal"><span style="font-family: arial;">These new contour plot controls provide additional tools that
can assist the user in producing customized report- or presentation-ready
graphics from your <span style="color: #3d85c6;"><b>TS-CHEM</b></span> plume transport modeling analyses.</span><o:p></o:p></p><p class="MsoNormal"><span style="font-family: arial;">To learn more about the <a href="https://transportstudio.com/software.php" target="_blank">new features</a> of <b><span style="color: #3d85c6;">TS-CHEM v2023-1</span></b>, or to download a <a href="https://transportstudio.com/pricing.php" target="_blank">FREE DEMO VERSION</a> of the software, visit the <a href="https://transportstudio.com/" target="_blank">TS-CHEM Website</a> today!</span></p><p class="MsoNormal"><br /></p><p class="MsoNormal"><br /></p><span style="font-family: arial;"></span><p></p><p class="MsoNormal"><span style="font-family: arial;"><br /></span></p>flexAEMhttp://www.blogger.com/profile/06315034871207029515noreply@blogger.com0tag:blogger.com,1999:blog-2626672773765534936.post-30097564195232699132023-04-14T14:07:00.002-07:002023-04-14T14:07:59.914-07:00State and Federal Guidance Spotlight - Use of TS-CHEM for Estimation of NJDEP Classification Exception Areas<p> <b><u>Introduction</u></b></p><p>There are a number of state and federal regulatory documents that prescribe the use of solute transport models to support site investigation and remediation activities, along with guidelines on the types of analyses that need to be performed, models that should be utilized, and in some instances, specific input parameters that must be incorporated into analyses. Common applications of solute transport models in state and federal guidance documents include analyses to estimate the expected extent and duration of groundwater plumes, whether sensitive receptors may be impacted, and as a line of evidence to support Monitored Natural Attenuation (MNA) evaluations. In this first post in the “State and Federal Guidance Spotlight” series, we take a look at the New Jersey Department of Environmental Protection’s (NJDEP’s) <a href="https://www.state.nj.us/dep/srp/guidance/cea/cea_guide.htm" target="_blank"><span style="color: #2b00fe;">Classification Exception Area Guidance</span></a>, and how TS-CHEM can be used to estimate plume extent and duration to support the delineation of Classification Exception Areas for sites where impacts to groundwater may be present.</p><p><b><u>Overview of NJDEP CEA Guidance</u></b></p><p>In the state of New Jersey, groundwaters of the state are classified according to a combination of natural characteristics and actual or potential uses, and groundwater quality standards (GWQS) have been established for these classification areas to ensure that the characteristics and/or actual and potential uses are protected. In instances where GWQS may not be met in a particular area (e.g., an area where impacted groundwater may be present as a result of a discharge of contaminants into the subsurface), the NJDEP requires the establishment of a Classification Exception Area (CEA), which provides notice that the constituent standards for a given aquifer classification are not (or will not) be met over a particular localized area, and that designated aquifer uses in the affected area are suspended for the duration of CEA term. </p><p>CEAs have three main components, including 1) delineation of the horizontal and vertical boundaries of the affected exception area; 2) identification of all groundwater constituents of concern (COCs) to which the exception applies; and 3) an estimate of the longevity of the CEA (i.e., the duration in which COCs will remain above GWQS within the exception area). In the event that the designated use of groundwater within the CEA includes potable use, the NJDEP will identify the CEA as a Well Restriction Area (WRA), which functions as an institutional control by which potable use restriction can be effected (though the NJDEP will not typically prohibit the installation of wells in WRAs).</p><p>Appendix A of the NJDEP CEA Guidance provides an overview of the methods that may be used for CEA delineation, and in particular, how to estimate the amount of time required for COCs to reach the GWQS, and the distance in which COCs are anticipated to migrate. With regard to the latter, as long as a sufficient amount of sampling data have been collected, the NJDEP recommends that a “best-fit” methodology to estimate COC attenuation rates (such as the methodology described in the 2003 USEPA issue paper “<i><a href="https://nepis.epa.gov/Exe/ZyNET.exe/10004674.TXT?ZyActionD=ZyDocument&Client=EPA&Index=2000+Thru+2005&Docs=&Query=&Time=&EndTime=&SearchMethod=1&TocRestrict=n&Toc=&TocEntry=&QField=&QFieldYear=&QFieldMonth=&QFieldDay=&IntQFieldOp=0&ExtQFieldOp=0&XmlQuery=&File=D%3A%5Czyfiles%5CIndex%20Data%5C00thru05%5CTxt%5C00000005%5C10004674.txt&User=ANONYMOUS&Password=anonymous&SortMethod=h%7C-&MaximumDocuments=1&FuzzyDegree=0&ImageQuality=r75g8/r75g8/x150y150g16/i425&Display=hpfr&DefSeekPage=x&SearchBack=ZyActionL&Back=ZyActionS&BackDesc=Results%20page&MaximumPages=1&ZyEntry=1&SeekPage=x&ZyPURL" target="_blank"><span style="color: #2b00fe;">Calculation and Use of First-Order Rate Constants for Monitored Natural Attenuation Studies</span></a></i>”), which can be used to calculate the anticipated time to reach the GWQS. With regard to the estimation of the maximum distance a plume is expected to travel, the NJDEP identifies several different numerical models that may be used, as well as a more simple analytical solution, which is often utilized by environmental practitioners responsible for the delineation of CEAs at sites in the state of New Jersey. As discussed in a recent <a href="https://ts-chem.blogspot.com/2023/03/1-d-vs-3-d-transport-analysis-of.html" target="_blank"><span style="color: #2b00fe;">TS-CHEM Blog Post</span></a>, however, a 1-dimensional analysis of contaminant transport (such as the one described in Appendix A of the NJDEP CEA Guidance) often greatly overestimates plume extent, resulting in an overly-conservative assessment. Fortunately, TS-CHEM provides a library of analytical and semi-analytical solute transport modeling solutions that can be used to estimate both the length and duration of groundwater plumes more accurately, without the steep learning curve typically associated with more sophisticated numerical models.</p><p><b><u>CEA Delineation Using TS-CHEM</u></b></p><p>As noted above, TS-CHEM, with a library of more than 30 analytical solutions, is perfectly suited to analyze the length and duration of groundwater plumes to assist with CEA development. The library of solutions allows for the selection of model that is best suited to conditions at a particular site. For example, at a site where source concentrations appear to be attenuating exponentially, a model like BIOSCREEN-AT may be a good fit. Or, if source concentrations are variable over time (e.g., as a result of site remediation activities), a model like ATRANS4 may provide the best solution. And since these models are semi-analytical solutions that analyze the transport of COCs in three dimensions, they are not overly conservative, and as such, will not result in an estimated plume length (and CEA delineation) that is much larger than it is realistically likely to be.</p><p></p><p>In addition to allowing for the selection of a model solution that best fits conditions at a site, TS-CHEM’s built-in charting and mapping tools can be used to generate all of the necessary output for documenting your analyses (as required when submitting a CEA application), including:</p><div><div><ul style="text-align: left;"><li>Charts showing concentration vs. distance and concentration vs. time</li><li>Plots showing plume extents through time</li><li>Mapping tools that allow for the overlay on an interactive digital map of the maximum plume extent in the direction of groundwater flow; or the mapping of plume extent through time to support an application at some point in time for a reduction of the CEA area</li></ul><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgNADJpCtPP1-eyBjjPzIeaci_8Y4b7-ERAjgsfo8uyU-UAG6LCQa74j8OejOC-kJXS1KSYwGmGmS2ZaMf507vUFt_-Vs7HBf_TKL0yIdJgtYDnLWrFRR0m_XoPzTmI7n80lFwt_IqWAKHm0lwstkLbb8zJ-W8rhHbLKboGh7tXKDLExS6xX1f5daTFtQ/s1808/Figure%201.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="1269" data-original-width="1808" height="450" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgNADJpCtPP1-eyBjjPzIeaci_8Y4b7-ERAjgsfo8uyU-UAG6LCQa74j8OejOC-kJXS1KSYwGmGmS2ZaMf507vUFt_-Vs7HBf_TKL0yIdJgtYDnLWrFRR0m_XoPzTmI7n80lFwt_IqWAKHm0lwstkLbb8zJ-W8rhHbLKboGh7tXKDLExS6xX1f5daTFtQ/w640-h450/Figure%201.png" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><i><b>Figure 1</b> - Use of TS-CHEM mapping tool to overlay depiction of maximum plume extent in the direction of groundwater flow</i></td></tr></tbody></table><br /><br /><div>To learn more about TS-CHEM and how it can be used to assist with the estimation of the extent and duration of contaminant plumes, or to download a <a href="https://transportstudio.com/downloads.php" target="_blank"><span style="color: #2b00fe;">FREE DEMO</span></a> of the software, visit the <span style="color: #2b00fe;"><a href="https://transportstudio.com/software.php" target="_blank">TS-CHEM Website</a> </span>today!</div></div></div><div><br /></div><div><br /></div>flexAEMhttp://www.blogger.com/profile/06315034871207029515noreply@blogger.com0tag:blogger.com,1999:blog-2626672773765534936.post-14543976684454656362023-03-24T12:57:00.001-07:002023-03-24T13:18:38.221-07:00TS-CHEM Example Applications – Receptor Impact Assessment<div style="text-align: left;"><span style="font-family: Calibri; font-size: large; line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;">TS-CHEM is not only simple and easy to use, but it can be applied
to a number of different common situations
when it comes to impacted groundwater, making
it the perfect tool for environmental professionals who perform groundwater
investigation and remediation activities. To show how TS-CHEM can be used to
evaluate a number of common groundwater issues, we have created a series of
Example Applications. In this blog post,
we introduce the first Example Application in the series, which demonstrates
how TS-CHEM can be used to model the length of a contaminant plume (in this
case a benzene plume) in order to determine if it will impact domestic wells at
a nearby residential development. You can download the model files and
accompanying overview slide deck for the example application described below <a href="https://transportstudio.com/example-applications.php">HERE</a>.</span></div><p class="MsoNormal"><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><b><span style="font-family: Calibri;"><span style="color: #0b5394; font-size: x-large;">Overview</span><span style="font-size: medium;"><o:p></o:p></span></span></b></p>
<div style="text-align: left;"><span style="font-family: Calibri; font-size: large; line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;">In Example Application 1, there has been a small
leak beneath a dispenser island at a gasoline station. This leak has led to a
release of benzene into the groundwater below the site with the source
concentrated near monitoring well MW-4. A residential development is located
1200 ft (1/4 mile) away from the leak location, and there is concern as to
whether domestic wells may be impacted by benzene. TS-CHEM can be utilized to determine whether the
dissolved benzene plume from the dispenser release will reach the domestic
wells above the drinking water standard of 5 ug/L.</span></div><div><span face=""Calibri",sans-serif" style="font-size: 11pt; line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;"><br /></span></div><div><span face=""Calibri",sans-serif" style="line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;"><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="font-size: 11pt; margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEhyETA7iJ60SPcwMbjL5f1JqNFAh7gj0K-HynUNL3efyIINKhz6itmH7x_Z47XmyT3eCIo9Y2wqHQMpU-Xax98lJtTjb_qnYO-hkPDr0qsCoeclnRs2Fox08drIDn17Hpjrrr57b1VC7WpnupZ4h39RD8GrXUzRbvwuUXSeFJXcg7Rd9BF6ConfGsK5zg" style="margin-left: auto; margin-right: auto;"><img data-original-height="542" data-original-width="975" height="356" src="https://blogger.googleusercontent.com/img/a/AVvXsEhyETA7iJ60SPcwMbjL5f1JqNFAh7gj0K-HynUNL3efyIINKhz6itmH7x_Z47XmyT3eCIo9Y2wqHQMpU-Xax98lJtTjb_qnYO-hkPDr0qsCoeclnRs2Fox08drIDn17Hpjrrr57b1VC7WpnupZ4h39RD8GrXUzRbvwuUXSeFJXcg7Rd9BF6ConfGsK5zg=w640-h356" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-size: 11pt; line-height: 100%;">Fig
1. Site map showing the distance from the benzene source at the dispenser
island to the residential area. </span></td></tr></tbody></table><div class="separator" style="clear: both; font-size: 11pt; text-align: center;"><br /></div><div class="separator" style="clear: both; font-size: 11pt; text-align: center;"><br /></div><p class="MsoNormal"><b><span style="font-family: Calibri;"><span style="color: #0b5394; font-size: x-large;">Setting up The Model</span><o:p style="font-size: 11pt;"></o:p></span></b></p>
<div style="text-align: left;"><span style="font-family: Calibri; font-size: large; line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;">Considering the benzene release recently occurred and no
remediation has taken place yet, we want to treat the contamination source as
constant source rather than a decaying or transient source. Therefore, ATRANS1
is the perfect model solution for this scenario since it is a continuous and
constant source model, and it will allow for a conservative evaluation of the
maximum extent of the benzene plume. <o:p></o:p></span></div><div style="text-align: left;"><span style="font-family: Calibri; font-size: large; line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;"><br /></span></div>
<div style="text-align: left;"><span style="font-family: Calibri; font-size: large; line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;">Once we’ve chosen ATRANS1 as our model solution, we need to
input all of the necessary model parameters that have been measured or
estimated from a preliminary investigation of the station, as shown below:</span></div><p class="MsoNormal"></p><ul style="text-align: left;"><li><span style="font-family: Calibri; font-size: large; text-indent: -0.25in;">Hydraulic gradient = 0.003 ft/ft</span></li><li><span style="font-family: Calibri; font-size: large; text-indent: -0.25in;">Hydraulic conductivity = 60 ft/d</span></li><li><span style="font-family: Calibri; font-size: large; text-indent: -0.25in;">Effective porosity = 0.25</span></li><li><span style="font-family: Calibri; font-size: large; text-indent: -0.25in;">Benzene source concentration = 3,000 ug/L</span></li><li><span style="font-family: Calibri; font-size: large; text-indent: -0.25in;">Source width (width of dispenser island) = 10 ft</span></li><li><span style="font-family: Calibri; font-size: large; text-indent: -0.25in;">Source depth (smear zone thickness beneath water
table) = 2 ft</span></li></ul><p></p></span></div><div><span face=""Calibri",sans-serif" style="font-size: 11pt; line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;"><p class="MsoListParagraphCxSpLast" style="mso-list: l0 level1 lfo1; text-indent: -0.25in;"><o:p></o:p></p>
</span><span face=""Calibri",sans-serif" style="line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;"><p class="MsoNormal" style="font-size: 11pt;"><o:p> </o:p></p>
<p class="MsoNormal"><b><span style="font-family: Calibri;"><span style="color: #0b5394; font-size: x-large;">Analysis 1</span><o:p style="font-size: 11pt;"></o:p></span></b></p>
</span><div style="text-align: left;"><span face=""Calibri",sans-serif" style="line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;"><span style="font-family: Calibri; font-size: large; line-height: 100%;">First, we set two model observation points
downgradient from the source at 600 ft and 1000 ft away. This will allow us to
view the rise and stabilization of the benzene plume at these locations. Next, we
run the model for a duration of 10 years. Once the model is finished running, we
can display the concentration versus time (C v t) chart:</span></span></div></div><div><span face=""Calibri",sans-serif" style="font-size: 11pt; line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;"><span style="font-size: 11pt; line-height: 100%;"><br /></span></span></div><div><span face=""Calibri",sans-serif" style="line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;"><span style="line-height: 100%;"><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="font-size: 11pt; margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEj3Dr1aByAFoO0rI8EsY_4_X7kk2eYG5mJLQWYBLknGMqPG761Xc2Uj6rUEnxkmzUN4rEbWhqJwkMFudKT2npG5TQ1WDn_uWGzQI7VCMxfJUHKlpXhyMFkyQFHRDjRwHDqW7j4fi5c3auDIzDF6h8Xx3_5hC7N4kwMigGY1cPoj-iwaXM0AVb3-kXXxVg" style="margin-left: auto; margin-right: auto;"><img data-original-height="574" data-original-width="975" height="376" src="https://blogger.googleusercontent.com/img/a/AVvXsEj3Dr1aByAFoO0rI8EsY_4_X7kk2eYG5mJLQWYBLknGMqPG761Xc2Uj6rUEnxkmzUN4rEbWhqJwkMFudKT2npG5TQ1WDn_uWGzQI7VCMxfJUHKlpXhyMFkyQFHRDjRwHDqW7j4fi5c3auDIzDF6h8Xx3_5hC7N4kwMigGY1cPoj-iwaXM0AVb3-kXXxVg=w640-h376" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="line-height: 100%;"><span style="font-size: 11pt;">Fig
2. The C v t chart in TS-CHEM displaying benzene concentrations near the source
at MW-1 (dark blue), 600 ft from the source (aqua), and 1000 ft from the source
(red).</span><br /><div style="text-align: left;"><span style="font-size: 14.6667px;"><br /></span></div></span></td></tr></tbody></table><div style="text-align: left;"><span style="font-family: Calibri; font-size: large; line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;"><br /></span></div><div style="text-align: left;"><span style="font-family: Calibri; font-size: large; line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;">The dark blue line shows that benzene concentrations at MW-1
where groundwater leaves the station property stabilize at around 76 ug/L,
while our observation points we set at 600 ft and 1000 ft show benzene
concentrations stabilizing around 11 ug/L and 3 ug/L, respectively. This chart
shows how the stabilized concentration of benzene decreases as you move further
away from the gas station. <o:p></o:p></span></div>
<span style="font-family: Calibri; font-size: large; line-height: 100%;">Now, let’s take a look at our contour chart set
to model year 10:</span></span></span></div><div><span face=""Calibri",sans-serif" style="font-size: 11pt; line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;"><span style="font-size: 11pt; line-height: 100%;"><br /></span></span></div><div><span face=""Calibri",sans-serif" style="font-size: 11pt; line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;"><span style="font-size: 11pt; line-height: 100%;"><br /><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEgkLwLVm8DqaI7aoIwe7UpYhnHjDFEY6B_xExB68Im3szHLnCN6ab_HsaJDatH2vgPDJnSgaJQFB47vs0qrKrUtf-tqWSuAHIe5m2OYUs-vBtDcncDSVc-kKkuXMkzOy8IdaumWfPvnNtz-9A9vXiYslxBIAv77_TfmbGtkTwn38qSxQfbhqrWsh8u_-A" style="margin-left: auto; margin-right: auto;"><img data-original-height="571" data-original-width="975" height="374" src="https://blogger.googleusercontent.com/img/a/AVvXsEgkLwLVm8DqaI7aoIwe7UpYhnHjDFEY6B_xExB68Im3szHLnCN6ab_HsaJDatH2vgPDJnSgaJQFB47vs0qrKrUtf-tqWSuAHIe5m2OYUs-vBtDcncDSVc-kKkuXMkzOy8IdaumWfPvnNtz-9A9vXiYslxBIAv77_TfmbGtkTwn38qSxQfbhqrWsh8u_-A=w640-h374" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-size: 11pt; line-height: 100%;">Fig
3. TS-CHEM’s contour chart indicates that the maximum plume extent (bound at 5
ug/L) does not reach the residential area.<br /></span></td></tr></tbody></table><br /><br /></span></span></div><div><span face=""Calibri",sans-serif" style="line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;"><span style="font-family: Calibri; line-height: 100%;"><div style="text-align: left;"><span style="font-family: Calibri; font-size: large; line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;">In the chart above, we’ve set the plume boundary to 5 ug/L,
which in this example, is the applicable drinking water standard for benzene.
Notice how the maximum extent of the plume does not reach the neighborhood
under these model conditions. In this case, one might conclude that based on the
results of the analysis, the benzene contamination at the gas station does not
impact receptors (domestic wells).</span></div><div style="text-align: left;"><span style="font-family: Calibri; font-size: large; line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;"><br /></span></div><p class="MsoNormal">
</p><p class="MsoNormal"><b><span style="color: #0b5394; font-size: x-large;">Analysis 2</span><o:p style="font-size: 11pt;"></o:p></b></p>
<div style="text-align: left;"><span style="font-family: Calibri; font-size: large; line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;">As noted above, the initial analyses performed using ATRANS
1 indicate that groundwater concentrations are not likely to reach downgradient
receptor wells above 5 ug/L. However, let’s say that local regulations impose a
different standard, and we must now evaluate a drinking water standard for
benzene of 1 ug/L. Accordingly, we will need to perform an additional analysis
to evaluate whether downgradient receptor wells may be impacted at
concentrations above 1 ug/L.<o:p></o:p></span></div>
<span style="font-size: large; line-height: 100%;">Since nothing at our site has changed (including
aquifer characteristics, source concentrations, and source size), we just have
to adjust our outer plume contour from 5 ug/L to 1 ug/L. Once we’ve changed the
plume contour, we can re-examine the contour chart at model year ten:</span><p></p></span></span></div><div><span face=""Calibri",sans-serif" style="font-size: 11pt; line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;"><span style="font-size: 11pt; line-height: 100%;"><span style="font-size: 11pt; line-height: 100%;"><br /></span></span></span></div><div><span face=""Calibri",sans-serif" style="line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;"><span style="line-height: 100%;"><span style="line-height: 100%;"><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="font-size: 11pt; margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEgIrAnxWfhaGgD_6RfVImBBERprxvbv783N_ZCIWWzs0cQCgS9zoclfxYetR6u1QCSNUFD_aX7nAE79mQqufXJPxyCoctYce5HHe6ORI3iZM9kt4gLtZI4dgv6QiWVNSAl8xQI-LlXzUrP6eo51oD9UaRY7BNIlKXiIMooUefKUjc2EZJOskL1LXG5sJA" style="margin-left: auto; margin-right: auto;"><img data-original-height="576" data-original-width="975" height="378" src="https://blogger.googleusercontent.com/img/a/AVvXsEgIrAnxWfhaGgD_6RfVImBBERprxvbv783N_ZCIWWzs0cQCgS9zoclfxYetR6u1QCSNUFD_aX7nAE79mQqufXJPxyCoctYce5HHe6ORI3iZM9kt4gLtZI4dgv6QiWVNSAl8xQI-LlXzUrP6eo51oD9UaRY7BNIlKXiIMooUefKUjc2EZJOskL1LXG5sJA=w640-h378" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-size: 11pt; line-height: 100%;">Fig
4. TS-CHEM’s contour chart indicates that the benzene plume, with a boundary of
1 ug/L, will impact the residential area.</span></td></tr></tbody></table><br /><div style="text-align: left;"><span style="font-family: Calibri; font-size: large; line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;">As shown in Figure 4 above, the plume visibly extends much
further to the east than it did in Analysis 1 (Figure 3), and therefore, our
conclusion has changed; under this more stringent drinking water standard, the
benzene spill at the gas station may impact downgradient receptors. But as
noted above, these analyses are very conservative. What if more reasonable inputs are used?</span></div><div style="text-align: left;"><span style="font-family: Calibri; font-size: large; line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;"><br /></span></div>
<p class="MsoNormal"><b><span style="font-family: Calibri;"><span style="color: #0b5394; font-size: x-large;">Analysis 3</span><o:p style="font-size: 11pt;"></o:p></span></b></p>
<span style="font-family: Calibri; font-size: large; line-height: 100%;">Oftentimes, regulatory agencies prescribe longer
half lives for constituents for the purposes of risk evaluations. In many
cases, however, half-lives of contaminants like benzene are shorter than the default
degradation rates typically prescribed by regulatory agencies. In our last two
analyses, we used the default degradation rate of 9.58E-04 d<sup>-1</sup> (half
life = 2 years). Let’s change the degradation rate to a more realistic value of
3.8E-03 d<sup>-1</sup> (half life = 0.5 years). After running the model again,
there is a noticeable difference in the concentration and length of the benzene
plume.</span></span></span></span></div><div><span face=""Calibri",sans-serif" style="font-size: 11pt; line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;"><span style="font-size: 11pt; line-height: 100%;"><span style="font-size: 11pt; line-height: 100%;"><span style="font-size: 11pt; line-height: 100%;"><br /></span></span></span></span></div><div><span face=""Calibri",sans-serif" style="line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;"><span style="line-height: 100%;"><span style="line-height: 100%;"><span style="line-height: 100%;"><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="font-size: 11pt; margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEilLIKIfl9t-8162h6N5A-kPp7Vgt7jUXNYtto182J5fkJXTyNHQpotzmspsQDpnQBLordtWo44JAePFLKcwzCxQJLkiHy3OAHHKCPmAPf-W7PBJoXBFqhny6USttNflEUfrhmUtgZ8TmPeZoPIxUitNzfJMOvog7N64bJZ9TXvaqfbr8siuMcjeJ8t5A" style="margin-left: auto; margin-right: auto;"><img data-original-height="575" data-original-width="975" height="378" src="https://blogger.googleusercontent.com/img/a/AVvXsEilLIKIfl9t-8162h6N5A-kPp7Vgt7jUXNYtto182J5fkJXTyNHQpotzmspsQDpnQBLordtWo44JAePFLKcwzCxQJLkiHy3OAHHKCPmAPf-W7PBJoXBFqhny6USttNflEUfrhmUtgZ8TmPeZoPIxUitNzfJMOvog7N64bJZ9TXvaqfbr8siuMcjeJ8t5A=w640-h378" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-size: 11pt; line-height: 100%;">Fig
5. The C v t chart in TS-CHEM shows that benzene concentrations stabilize at a
much lower level when the degradation rate is increased.</span></td></tr></tbody></table><span style="font-family: Calibri;"><br /></span></span></span></span></span></div><div><span face=""Calibri",sans-serif" style="line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;"><span style="line-height: 100%;"><span style="line-height: 100%;"><span style="font-family: Calibri; font-size: large; line-height: 100%;">As
shown in Figure <span style="background-attachment: initial; background-clip: initial; background-color: white; background-image: initial; background-origin: initial; background-position: initial; background-repeat: initial; background-size: initial; background: white;">5</span>
above, the C v t chart shows that benzene stabilizes around 35 ug/L at MW-1
near the station property boundary, which is about half the concentration
observed in the previous analyses. Additionally, the benzene barely registers
at our downgradient observation points. Now let’s look at the contour chart to
examine the maximum extent of the plume using this higher degradation rate.</span></span></span></span></div><div><span face=""Calibri",sans-serif" style="font-size: 11pt; line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;"><span style="font-size: 11pt; line-height: 100%;"><span style="font-size: 11pt; line-height: 100%;"><span style="font-size: 11pt; line-height: 100%;"><br /></span></span></span></span></div><div><span face=""Calibri",sans-serif" style="line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;"><span style="line-height: 107%;"><span style="line-height: 100%;"><span style="line-height: 100%;"><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="font-size: 11pt; margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEggaCewrty9NIdouauaasDMGeTA86Iu0fhku1TJe0GF452SDsFfWdCizhjJV2VIGiePVRMghN7VgMnDIgBGKriUUIDnQepsgoYfMW0xcvJ_sudcJ6OrDEtOc40eqjf52x8gMm5iBRUhfG47xGdpuFLgzAcxHJrO6AsdpfXO8W-EYHklb7xumUnpZ4obtw" style="margin-left: auto; margin-right: auto;"><img data-original-height="575" data-original-width="975" height="378" src="https://blogger.googleusercontent.com/img/a/AVvXsEggaCewrty9NIdouauaasDMGeTA86Iu0fhku1TJe0GF452SDsFfWdCizhjJV2VIGiePVRMghN7VgMnDIgBGKriUUIDnQepsgoYfMW0xcvJ_sudcJ6OrDEtOc40eqjf52x8gMm5iBRUhfG47xGdpuFLgzAcxHJrO6AsdpfXO8W-EYHklb7xumUnpZ4obtw=w640-h378" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-size: 11pt; line-height: 100%;">Fig
6. The contour chart demonstrates the effect of increasing the degradation rate
of benzene. The plume, while still bound at the more protective 1 ug/L, no
longer impacts the residential area.</span></td></tr></tbody></table><br /><span style="font-family: Calibri; font-size: large; line-height: 100%;">Review
of contour charts for each model year indicates that the benzene plume
stabilizes in less than 4 years, which is about half the time it took the plume
to stabilize in the previous analyses. Also, the plume, bound at 1 ug/L,
reaches a maximum length of approximately 580 ft, and thus, does not impact the
neighborhood domestic wells. The length of the benzene plume observed in this
analysis is consistent with benzene plume lengths seen in many literature
studies such as <a href="https://www.api.org/~/media/files/ehs/clean_water/bulletins/08_bull.pdf">API
1998</a> and <a href="https://ngwa.onlinelibrary.wiley.com/doi/full/10.1111/gwat.12233">Connor
et al 2014</a>.</span></span></span></span></span></div><div><span face=""Calibri",sans-serif" style="font-size: 11pt; line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;"><span style="font-size: 11pt; line-height: 100%;"><span style="font-size: 11pt; line-height: 100%;"><span style="font-size: 11pt; line-height: 100%;"><span style="font-size: 11pt; line-height: 100%;"><br /></span></span></span></span></span></div><div><span face=""Calibri",sans-serif" style="line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;"><span style="line-height: 100%;"><span style="line-height: 100%;"><span style="line-height: 100%;"><span style="font-family: Calibri; line-height: 100%;"><p class="MsoNormal"><b><span style="color: #0b5394; font-size: x-large;">Why is this important?</span><o:p style="font-size: 11pt;"></o:p></b></p>
<div style="text-align: left;"><span style="font-family: Calibri; font-size: large; line-height: 100%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;">In the case of a leak or spill of hazardous substances,
government agencies may require some form of receptor impact evaluation in
order to protect people and ecological receptors from exposure to
contamination. TS-CHEM is a quick and easy, and science-base, way for any
environmental professional to assess potential risks to receptors, evaluate the
effect of changes in input parameters, and support decisions regarding the
possible need for remedial actions. With over 30 solution models to choose from
and a library of the most commonly modeled constituents, you can select an
appropriate model and quickly (and easily) perform a receptor impact evaluation
at your site!</span></div>
<span style="font-size: large; line-height: 100%;">To learn more about TS-CHEM, or to download a <a href="https://transportstudio.com/downloads.php">FREE DEMO</a> of the software,
visit the <a href="https://transportstudio.com/">TS-CHEM Website</a>! If you
would like to see what else TS-CHEM can do, check out our other <a href="https://transportstudio.com/example-applications.php">Example
Applications</a>!</span></span></span></span></span></span></div>flexAEMhttp://www.blogger.com/profile/06315034871207029515noreply@blogger.com0tag:blogger.com,1999:blog-2626672773765534936.post-16745653858030462122023-03-02T12:08:00.035-08:002023-03-02T13:59:30.324-08:001-D vs 3-D Transport Analysis of Contaminant Plume Extent<p><b> <i><span face=""Verdana",sans-serif" style="font-size: 11pt; line-height: 107%; mso-ansi-language: EN-US; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin;">A
1-D analysis of contaminant transport often greatly overestimates plume extent,
resulting in an overly-conservative assessment.</span></i></b></p><p><i><span face=""Verdana",sans-serif" style="font-size: 11pt; line-height: 107%; mso-ansi-language: EN-US; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin;"><br /></span></i></p><p></p><p class="MsoNormal" style="margin-bottom: 0in;"><span face=""Verdana",sans-serif">A common question related to contaminant plumes: “How far downgradient will the plume extend?”<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-bottom: 0in;"><span face=""Verdana",sans-serif">We
may want to know this for several reasons:<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-bottom: 0in; margin-left: 1.0in; margin-right: 0in; margin-top: 0in; margin: 0in 0in 0in 1in; mso-list: l0 level2 lfo1; tab-stops: list 1.0in; text-indent: -0.25in;"><!--[if !supportLists]--><span face=""Arial",sans-serif" style="mso-fareast-font-family: Arial;"><span style="mso-list: Ignore;">•<span style="font: 7pt "Times New Roman";">
</span></span></span><!--[endif]--><span face=""Verdana",sans-serif">Will
the plume reach a receptor at some distance from the source?<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-bottom: 0in; margin-left: 1.0in; margin-right: 0in; margin-top: 0in; margin: 0in 0in 0in 1in; mso-list: l0 level2 lfo1; tab-stops: list 1.0in; text-indent: -0.25in;"><!--[if !supportLists]--><span face=""Arial",sans-serif" style="mso-fareast-font-family: Arial;"><span style="mso-list: Ignore;">•<span style="font: 7pt "Times New Roman";">
</span></span></span><!--[endif]--><span face=""Verdana",sans-serif">How
far should I place monitoring wells to measure the plume?<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-bottom: 0in; margin-left: 1.0in; margin-right: 0in; margin-top: 0in; margin: 0in 0in 0in 1in; mso-list: l0 level2 lfo1; tab-stops: list 1.0in; text-indent: -0.25in;"><!--[if !supportLists]--><span face=""Arial",sans-serif" style="mso-fareast-font-family: Arial;"><span style="mso-list: Ignore;">•<span style="font: 7pt "Times New Roman";">
</span></span></span><!--[endif]--><span face=""Verdana",sans-serif">And
in some states (e.g. NJ) how far should I draw the boundary of the groundwater Classification
Exception Area (CEA).</span></p><p class="MsoNormal" style="margin-bottom: 0in; margin-left: 1.0in; margin-right: 0in; margin-top: 0in; margin: 0in 0in 0in 1in; mso-list: l0 level2 lfo1; tab-stops: list 1.0in; text-indent: -0.25in;"><br /></p><p class="MsoNormal" style="margin-bottom: 0in;"><b><span face=""Verdana",sans-serif"><span style="color: #e69138; font-size: large;">Possible
Methods</span><o:p></o:p></span></b></p><i><span face=""Verdana",sans-serif" style="font-size: 11pt; line-height: 107%; mso-ansi-language: EN-US; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin;"></span></i><p></p><p class="MsoNormal" style="margin-bottom: 0in; margin-left: 1.0in; margin-right: 0in; margin-top: 0in; margin: 0in 0in 0in 1in; mso-list: l0 level2 lfo1; tab-stops: list 1.0in; text-indent: -0.25in;">
</p><p class="MsoNormal" style="margin-bottom: 0in;"><span face=""Verdana",sans-serif">To
analyze plume extent from the source over time, we can perform screening
analyses using models ranging from simple analytic 1-D solutions, to 3-D analytic and
semi-analytic solutions. We could also use more costly and sophisticated 3-D
numerical fate and transport models - - but to examine the difference between a
1-D model and a 3-D model, analytical solutions are perfectly capable analysis
tools.</span></p><p class="MsoNormal" style="margin-bottom: 0in;"><span face=""Verdana",sans-serif"><br /></span></p><p class="MsoNormal" style="margin-bottom: 0in;"></p><p class="MsoNormal" style="margin-bottom: 0in;"><b><span face=""Verdana",sans-serif"><span style="color: #3d85c6;">1-D
Plume Transport Modeling</span><o:p></o:p></span></b></p>
<p class="MsoNormal" style="margin-bottom: 0in;"><span face=""Verdana",sans-serif">For
many decades, from the 1970s through present, investigators and regulators have often explored the movement of a dissolved chemical plume extending downgradient
from a steadily-releasing source using some form of mathematical solution to
the 1-D transport equation (e.g. Ogata and Banks 1961; Bear 1972 & 1979). The
often cited Ogata and Banks 1961 solution is a simple representation of
advective-dispersive transport that does not incorporate the processes of
adsorption (retardation) nor degradation. The Bear 1972 & 1979 solutions
are more useful because they incorporate the effects of dispersion,
retardation, and degradation.<o:p></o:p></span></p><p class="MsoNormal" style="margin-bottom: 0in;"><span face=""Verdana",sans-serif"><br /></span></p><p class="MsoNormal" style="margin-bottom: 0in;"><b><span face="Verdana, sans-serif"><span style="color: #3d85c6;">1-D Example Application </span></span></b></p><p class="MsoNormal" style="margin-bottom: 0in;"><span face=""Verdana",sans-serif">To
illustrate the plume length that a 1-D model would calculate, a simple example
was developed in which the Bear 1-D transport solution was used to calculate the
location of the 5 ug/L plume boundary of a benzene plume 5880 days (16 years)
after release (<b>Fig 1</b>). Source benzene concentration was assumed to remain
constant at 1000 ug/L; groundwater velocity was set to 1 ft/d and retardation
factor was set to 2; 1-D aquifer dispersivity was 50 ft; and a conservative
benzene plume half-life of 2 years was applied. <o:p></o:p></span></p><p class="MsoNormal" style="margin-bottom: 0in;"></p><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg-XhWLR2J4-yHUbDnv13b8vM8IBA2uQmVPYaIG5wodaHHN4UrqfZw4fzU_F3MlvrmPfLN7BjseWF5n-mD7UyEcRLJ3oi3PS73EYpakhS5lcK6O8D78chY3hZj8QnSR7wsfLXHhjDZxj688e1X3PdREmaAwICITro7K0q6-pNz3f8ZYJwF4KCmJmnXJGg/s533/Picture1.png" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="338" data-original-width="533" height="406" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg-XhWLR2J4-yHUbDnv13b8vM8IBA2uQmVPYaIG5wodaHHN4UrqfZw4fzU_F3MlvrmPfLN7BjseWF5n-mD7UyEcRLJ3oi3PS73EYpakhS5lcK6O8D78chY3hZj8QnSR7wsfLXHhjDZxj688e1X3PdREmaAwICITro7K0q6-pNz3f8ZYJwF4KCmJmnXJGg/w640-h406/Picture1.png" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><b>Fig 1. 1-D calculation shows plume extends 2900 ft from the source after 5880 days.</b></td></tr></tbody></table><span face=""Verdana",sans-serif"><br /></span><p></p><p class="MsoNormal" style="margin-bottom: 0in;"><b><span face=""Verdana",sans-serif"><span style="color: #3d85c6;">3-D
Plume Transport Modeling</span><o:p></o:p></span></b></p><p class="MsoNormal" style="margin-bottom: 0in;">
</p><p class="MsoNormal" style="margin-bottom: 0in;"><span face=""Verdana",sans-serif">Another
approach often employed by investigators or regulators is to begin with the
full 3-D transport equation and apply that 3-D solution to calculate
concentration along the <i>centerline</i> of the plume to determine the extent of the
plume in the downgradient direction.<o:p></o:p></span></p><p class="MsoNormal" style="margin-bottom: 0in;"><span face=""Verdana",sans-serif">One
of the widely known solutions to the 3-D transport equations was developed by
Domenico in 1987. This solution forms the basis for a number of models used by
regulatory agencies to estimate contaminant plume movement:<o:p></o:p></span></p><p class="MsoNormal" style="margin-bottom: 0in; margin-left: 31.5pt; margin-right: 0in; margin-top: 0in; margin: 0in 0in 0in 31.5pt; mso-list: l0 level2 lfo1; text-indent: -13.5pt;"><!--[if !supportLists]--><span face=""Arial",sans-serif" style="mso-fareast-font-family: Arial;">•<span style="font-family: "Times New Roman"; font-size: 7pt; font-stretch: normal; font-variant-east-asian: normal; font-variant-numeric: normal; line-height: normal;">
</span></span><!--[endif]--><span face=""Verdana",sans-serif"><b>BIOSCREEN</b>
developed by USEPA (see USEPA website for BIOSCREEN v1.4)<o:p></o:p></span></p><p class="MsoNormal" style="margin-bottom: 0in; margin-left: 31.5pt; margin-right: 0in; margin-top: 0in; margin: 0in 0in 0in 31.5pt; mso-list: l0 level2 lfo1; text-indent: -13.5pt;"><!--[if !supportLists]--><span face=""Arial",sans-serif" style="mso-fareast-font-family: Arial;">•<span style="font-family: "Times New Roman"; font-size: 7pt; font-stretch: normal; font-variant-east-asian: normal; font-variant-numeric: normal; line-height: normal;">
</span></span><!--[endif]--><span face=""Verdana",sans-serif"><b>BIOCHLOR
(USEPA) v 2.2</b></span></p><p class="MsoNormal" style="margin-bottom: 0in; margin-left: 31.5pt; margin-right: 0in; margin-top: 0in; margin: 0in 0in 0in 31.5pt; mso-list: l0 level2 lfo1; text-indent: -13.5pt;"><span face="Arial, sans-serif" style="text-indent: -13.5pt;">•<span style="font-family: "Times New Roman"; font-size: 7pt; font-stretch: normal; font-variant-east-asian: normal; font-variant-numeric: normal; line-height: normal;"> <b>
</b></span></span><span face="Verdana, sans-serif" style="text-indent: -13.5pt;"><b>Quick
Domenico model</b> described by PADEP in certain of its regulatory documents (see
PADEP website Quick Domenico spreadsheet model)</span></p><p class="MsoNormal" style="margin-bottom: 0in; margin-left: 31.5pt; margin-right: 0in; margin-top: 0in; margin: 0in 0in 0in 31.5pt; mso-list: l0 level2 lfo1; text-indent: -13.5pt;"><br /></p><p class="MsoNormal" style="margin-bottom: 0in;"><b><span face="Verdana, sans-serif"><span style="color: #3d85c6;">3-D Example Application </span></span></b></p><p class="MsoNormal" style="margin-bottom: 0in;"><span face=""Verdana",sans-serif">So, we can now solve the same plume transport problem illustrated in <b>Fig 1</b>, but we will instead use the 3-D Domenico solution model (instead of 1-D). Transverse dispersivity is
set to 1/10<sup>th</sup> the longitudinal dispersivity and vertical dispersivity is
set to 1/1000<sup>th</sup> the longitudinal dispersivity (these parameters were not present in the 1-D model). The 3-D transport solution
calculates a much shorter plume length; 1280 ft versus the 1-D length of 2900 ft
(<b>Fig 2</b>).<o:p></o:p></span></p><p class="MsoNormal" style="margin-bottom: 0in;"></p><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgiuKwYJb_s9y1pmGQ915tLIJBPx52qcNBOJRObqW_0HMIuvW8pZJism94Vk550DhsRSO0_8bKXMApxlJfFYWdqmB0onhaR-cyjW4ZrPMYUZsAMSwlGZIgUHdZt5Zt1tgWFQG5ETnZkJDgMPnXyUnd5alxrtVcuNGDPKVIGdtN6Vzqw054sfT1-puq2rQ/s624/Picture2.png" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="285" data-original-width="624" height="292" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgiuKwYJb_s9y1pmGQ915tLIJBPx52qcNBOJRObqW_0HMIuvW8pZJism94Vk550DhsRSO0_8bKXMApxlJfFYWdqmB0onhaR-cyjW4ZrPMYUZsAMSwlGZIgUHdZt5Zt1tgWFQG5ETnZkJDgMPnXyUnd5alxrtVcuNGDPKVIGdtN6Vzqw054sfT1-puq2rQ/w640-h292/Picture2.png" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><b>Fig 2. 3-D calculation shows plume extends 1280 ft from the source after 5880 days.</b></td></tr></tbody></table><br /><p></p><p class="MsoNormal" style="margin-bottom: 0in;"><b><span style="background-color: white; color: #e69138; font-family: verdana; font-size: large;">Newer
3-D Methods</span></b></p><p class="MsoNormal" style="margin-bottom: 0in;"><b><span face=""Verdana",sans-serif"><span style="color: #3d85c6;">Analytical</span><o:p></o:p></span></b></p><p class="MsoNormal" style="margin-bottom: 0in;"><span face=""Verdana",sans-serif">In
recent years minor discrepancies have been reported between the Domenico solution
and more rigorous solutions to the 3-D transport equations (see for example (Guyonnet
and Neville 2004; West et al 2007; Srinivasan et al 2007; Karanovic et al 2007;
Devlin et al 2012). The discrepancies occur primarily along the centerline axis
of the plume; this means that errors may be introduced when attempting to
estimate the plume length (i.e. how far downgradient from the source
contamination may extend).<o:p></o:p></span></p><p class="MsoNormal" style="margin-bottom: 0in;"><span face=""Verdana",sans-serif">Several
investigators have modified the original Domenico 3-D transport solution to
attempt to mitigate the errors caused by the original formulation. For example:<o:p></o:p></span></p><p class="MsoNormal" style="margin-bottom: 0in; margin-left: 31.5pt; margin-right: 0in; margin-top: 0in; margin: 0in 0in 0in 31.5pt; mso-list: l0 level2 lfo1; text-indent: -13.5pt;"><!--[if !supportLists]--><span face=""Arial",sans-serif" style="mso-fareast-font-family: Arial;">•<span style="font-family: "Times New Roman"; font-size: 7pt; font-stretch: normal; font-variant-east-asian: normal; font-variant-numeric: normal; line-height: normal;">
</span></span><!--[endif]--><span face=""Verdana",sans-serif">BIOSCREEN
(USEPA) was updated to <b>BIOSCREEN-AT </b>(Karanovic & Neville 2007)<o:p></o:p></span></p><p class="MsoNormal" style="margin-bottom: 0in; margin-left: 31.5pt; margin-right: 0in; margin-top: 0in; margin: 0in 0in 0in 31.5pt; mso-list: l0 level2 lfo1; text-indent: -13.5pt;"><!--[if !supportLists]--><span face=""Arial",sans-serif" style="mso-fareast-font-family: Arial;">•<span style="font-family: "Times New Roman"; font-size: 7pt; font-stretch: normal; font-variant-east-asian: normal; font-variant-numeric: normal; line-height: normal;">
</span></span><!--[endif]--><span face=""Verdana",sans-serif">Srinivasan,
Clement & Lee (2007) published <b>an updated version of the Domenico solution</b><o:p></o:p></span></p><p class="MsoNormal" style="margin-bottom: 0in; margin-left: 31.5pt; margin-right: 0in; margin-top: 0in; margin: 0in 0in 0in 31.5pt; mso-list: l0 level2 lfo1; text-indent: -13.5pt;"><span face=""Verdana",sans-serif"><b><br /></b></span></p><p class="MsoNormal" style="margin-bottom: 0in;"><b><span face=""Verdana",sans-serif"><span style="color: #3d85c6;">Semi-Analytical</span><o:p></o:p></span></b></p><p class="MsoNormal" style="margin-bottom: 0in;"><span face=""Verdana",sans-serif">The
1-D and 3-D solutions we have examined to this point are analytic solutions.
Certain simplifications are made in the formulation of the transport
differential equation that allows it to be solved in closed form - - i.e. the
solution does not contain an integral term; the algebraic equation can be
solved in a spreadsheet<o:p></o:p></span></p><p class="MsoNormal" style="margin-bottom: 0in;"><span face="Verdana, sans-serif">There
is a class of more rigorous solutions that are <i>not simplified</i> and still contain
an integral term; and because of that, they are more accurate. These solutions are
typically solved in a simple program that employs a <i>numerical integration</i>
routine to arrive at the calculated concentrations.</span></p><p class="MsoNormal" style="margin-bottom: 0in;">
</p><p class="MsoNormal" style="margin-bottom: 0in;"><span face=""Verdana",sans-serif">Examples
of these semi-analytical transport models include:</span></p><p class="MsoNormal" style="margin-bottom: 0in; margin-left: 40.5pt; margin-right: 0in; margin-top: 0in; margin: 0in 0in 0in 40.5pt; mso-list: l0 level2 lfo1; tab-stops: list 40.5pt; text-indent: -0.25in;"><!--[if !supportLists]--><span face=""Arial",sans-serif" style="mso-fareast-font-family: Arial;">•<span style="font-family: "Times New Roman"; font-size: 7pt; font-stretch: normal; font-variant-east-asian: normal; font-variant-numeric: normal; line-height: normal;">
</span></span><!--[endif]--><span face=""Verdana",sans-serif"><b>ATRANS</b><o:p></o:p></span></p><p class="MsoNormal" style="margin-bottom: 0in; margin-left: 40.5pt; margin-right: 0in; margin-top: 0in; margin: 0in 0in 0in 40.5pt; mso-list: l0 level2 lfo1; tab-stops: list 40.5pt; text-indent: -0.25in;"><!--[if !supportLists]--><span face=""Arial",sans-serif" style="mso-fareast-font-family: Arial;">•<span style="font-family: "Times New Roman"; font-size: 7pt; font-stretch: normal; font-variant-east-asian: normal; font-variant-numeric: normal; line-height: normal;">
</span></span><!--[endif]--><span face=""Verdana",sans-serif"><b>BIOSCREEN-AT</b>
(Domenico 1987 solution modified by Karanovic et al 2007)<o:p></o:p></span></p><p class="MsoNormal" style="margin-bottom: 0in; margin-left: 40.5pt; margin-right: 0in; margin-top: 0in; margin: 0in 0in 0in 40.5pt; mso-list: l0 level2 lfo1; tab-stops: list 40.5pt; text-indent: -0.25in;"><!--[if !supportLists]--><span face=""Arial",sans-serif" style="mso-fareast-font-family: Arial;">•<span style="font-family: "Times New Roman"; font-size: 7pt; font-stretch: normal; font-variant-east-asian: normal; font-variant-numeric: normal; line-height: normal;">
</span></span><!--[endif]--><span face=""Verdana",sans-serif"><b>3DADE</b>
(USDA 1994)<o:p></o:p></span></p><p class="MsoNormal" style="margin-bottom: 0in; margin-left: 40.5pt; margin-right: 0in; margin-top: 0in; margin: 0in 0in 0in 40.5pt; mso-list: l0 level2 lfo1; tab-stops: list 40.5pt; text-indent: -0.25in;"><!--[if !supportLists]--><span face=""Arial",sans-serif" style="mso-fareast-font-family: Arial;">•<span style="font-family: "Times New Roman"; font-size: 7pt; font-stretch: normal; font-variant-east-asian: normal; font-variant-numeric: normal; line-height: normal;">
</span></span><!--[endif]--><span face=""Verdana",sans-serif"><b>N3DADE</b>
(USDA 1997)<o:p></o:p></span></p><p class="MsoNormal" style="margin-bottom: 0in; margin-left: 40.5pt; margin-right: 0in; margin-top: 0in; margin: 0in 0in 0in 40.5pt; mso-list: l0 level2 lfo1; tab-stops: list 40.5pt; text-indent: -0.25in;"><!--[if !supportLists]--><span face=""Arial",sans-serif" style="mso-fareast-font-family: Arial;">•<span style="font-family: "Times New Roman"; font-size: 7pt; font-stretch: normal; font-variant-east-asian: normal; font-variant-numeric: normal; line-height: normal;">
</span></span><!--[endif]--><span face=""Verdana",sans-serif"><b>AT123D-AT</b>
(Yeh 1984 solution modified by Burnell et al 2012)<o:p></o:p></span></p><p class="MsoNormal" style="margin-bottom: 0in;">
</p><p class="MsoNormal" style="margin-bottom: 0in;"><span face="Verdana, sans-serif">These
solutions have been assembled into a unified user interface in <span style="color: #e69138;"><b>TS-CHEM</b></span>. They
provide a means of calculating more accurate estimates of contaminant plume
extent for environmental assessments.</span></p><p class="MsoNormal" style="margin-bottom: 0in;"><br /></p><p class="MsoNormal" style="margin-bottom: 0in;"><span face=""Verdana",sans-serif"><b>To summarize: </b>Contaminant
plume analyses based on 1-D models are likely to greatly overestimate plume
extent. This may result in an overly-conservative assessment that causes
concern, or results in actions, related to impacts that are not likely to
occur. More accurate evaluations of plume extent can be calculated using 3-D
contaminant transport model. <b><span style="color: #e69138;">TS-CHEM</span></b> provides a </span><a href="https://transportstudio.com/downloads/TS-CHEM%20Solutions%20Features.pdf" style="font-family: Verdana, sans-serif; font-size: 11pt;">library
of over 30 analytical 3D plume transport solutions</a> for making these types of evaluations.</p><p class="MsoNormal" style="margin-bottom: 0in;"><span face=""Verdana",sans-serif"><br /></span></p><p class="MsoNormal" style="margin-bottom: 0in;"><span style="font-family: verdana;"><span style="background-color: white; text-align: justify;">To learn more about <span style="color: #e69138;"><b>TS-CHEM</b></span>, or to download a </span><a href="https://transportstudio.com/downloads.php" style="background-color: white; color: #265fd3; text-align: justify; text-decoration-line: none;"><span style="color: blue;">FREE DEMO VERSION</span></a><span style="background-color: white; text-align: justify;"> of the software, visit the </span><a href="https://transportstudio.com/" style="background-color: white; color: #265fd3; text-align: justify; text-decoration-line: none;"><span style="color: blue;">TS-CHEM Website</span></a><span style="background-color: white; text-align: justify;"> today!</span></span></p><p class="MsoNormal" style="margin-bottom: 0in;"><span face=""Verdana",sans-serif"><br /></span></p><p class="MsoNormal" style="margin-bottom: 0in;"><span face=""Verdana",sans-serif"><br /></span></p><p class="MsoNormal" style="margin-bottom: 0in;"><span face=""Verdana",sans-serif"><o:p></o:p></span></p><p class="MsoNormal" style="margin-bottom: 0in;">
</p><p class="MsoNormal" style="margin-bottom: 0in;"><span face=""Verdana",sans-serif"> </span></p><span face=""Verdana",sans-serif"></span><p></p>flexAEMhttp://www.blogger.com/profile/06315034871207029515noreply@blogger.com0tag:blogger.com,1999:blog-2626672773765534936.post-31191824949702726702023-02-22T12:47:00.085-08:002023-02-23T06:16:31.381-08:00TS-CHEM Solution Library - ATRANS<p style="text-align: left;"></p><p class="MsoNormal" style="line-height: normal; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; text-align: justify;"><span style="color: black; font-family: "Georgia",serif; font-size: 13.5pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">The TS-CHEM program
includes a </span><i><span style="color: #ed7d31; font-family: "Georgia",serif; font-size: 13.5pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">comprehensive library of more than 30 different analytical
solutions</span></i><span style="color: black; font-family: "Georgia",serif; font-size: 13.5pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">, each with different capabilities, including how they represent
contaminant sources. For this first post in the Solution Library series, we
will be focusing on the ATRANS family of models developed by Chris Neville at
SS Papadopulos & Associates. In fact, the ATRANS1 model is included in
the <a href="https://transportstudio.com/downloads.php"><i><span style="color: blue;">DEMO version of TS-CHEM</span></i></a>, so you can try it
out for yourself at any time!</span><span style="color: black; font-family: "Times New Roman",serif; font-size: 13.5pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p>
<p class="MsoNormal" style="line-height: normal; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; text-align: justify;"><span style="color: black; font-family: "Georgia",serif; font-size: 13.5pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";"> </span><span style="color: black; font-family: "Times New Roman",serif; font-size: 13.5pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p>
<p class="MsoNormal" style="line-height: normal; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto;"><b><span style="color: black; font-family: "Georgia",serif; font-size: 14pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">What is<i> </i>ATRANS?</span></b><span style="color: black; font-family: "Times New Roman",serif; font-size: 13.5pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p>
<p class="MsoNormal" style="line-height: normal; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; text-align: justify;"><span style="color: black; font-family: "Georgia",serif; font-size: 13.5pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">ATRANS is a suite of
analytical model solutions that are used to simulate three-dimensional
advective-dispersive transport from a </span><i><span style="color: #ed7d31; font-family: "Georgia",serif; font-size: 13.5pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">patch</span></i><span style="color: black; font-family: "Georgia",serif; font-size: 13.5pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";"> </span><i><span style="color: #ed7d31; font-family: "Georgia",serif; font-size: 13.5pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">source</span></i><span style="color: black; font-family: "Georgia",serif; font-size: 13.5pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";"> along
the inflow boundary of an aquifer, as show in the conceptual model below:</span><span style="color: black; font-family: "Times New Roman",serif; font-size: 13.5pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p><br /><p></p><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhgk7L0QKAo0Aa6H-jFdvZuMImDtg_Fp0-QHvGYsJjxFpLL6M-TmoIha48drtvm0vWbGlyfj36Lo4dcLAsrasfVHViYOESO7S-qqWIX_Jxf3-h44cbZN9bZHtJJ4KWQH21MzsHcx7Slf3XHIpt3It3-uYFFUDvMKDBt2Qk0D0qv4mOeKqXKJNVPwbsqWQ/s1579/Picture1.png" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="1579" data-original-width="1444" height="400" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhgk7L0QKAo0Aa6H-jFdvZuMImDtg_Fp0-QHvGYsJjxFpLL6M-TmoIha48drtvm0vWbGlyfj36Lo4dcLAsrasfVHViYOESO7S-qqWIX_Jxf3-h44cbZN9bZHtJJ4KWQH21MzsHcx7Slf3XHIpt3It3-uYFFUDvMKDBt2Qk0D0qv4mOeKqXKJNVPwbsqWQ/w366-h400/Picture1.png" width="366" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><i>Figure 1 - ATRANS conceptual model</i></td></tr></tbody></table><br /><div><p class="MsoNormal" style="line-height: normal; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; text-align: justify;"><span style="color: black; font-family: "Georgia",serif; font-size: 13.5pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">TS-CHEM includes all four
ATRANS models: ATRANS1, ATRANS2, ATRANS3 and ATRANS4. All ATRANS models are
based on the following key assumptions:</span><span style="color: black; font-family: "Times New Roman",serif; font-size: 13.5pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p>
<ul type="disc">
<li class="MsoNormal" style="color: black; line-height: normal; mso-list: l0 level1 lfo1; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; tab-stops: list .5in;"><span style="font-family: "Georgia",serif; font-size: 13.5pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">Finite aquifer
bounds (semi-finite in the x-direction, finite in the z-direction)</span><span style="font-family: "Times New Roman",serif; font-size: 13.5pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></li>
<ul type="circle">
<li class="MsoNormal" style="color: black; line-height: normal; mso-list: l0 level2 lfo1; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; tab-stops: list 1.0in;"><span style="font-family: "Georgia",serif; font-size: 7pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";"> </span><span style="font-family: "Georgia",serif; font-size: 13.5pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">This
essentially places no-mass-flux boundaries on the upper water-table
boundary and the lower aquifer base boundary</span><span style="font-family: "Times New Roman",serif; font-size: 13.5pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></li>
</ul>
<li class="MsoNormal" style="color: black; line-height: normal; mso-list: l0 level1 lfo1; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; tab-stops: list .5in;"><span style="font-family: "Georgia",serif; font-size: 13.5pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">Uniform
one-dimensional flow along the x-axis</span><span style="font-family: "Times New Roman",serif; font-size: 13.5pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></li>
<li class="MsoNormal" style="color: black; line-height: normal; mso-list: l0 level1 lfo1; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; tab-stops: list .5in;"><span style="font-family: "Georgia",serif; font-size: 13.5pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">First-order
reaction kinetics (e.g. biodegradation)</span><span style="font-family: "Times New Roman",serif; font-size: 13.5pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></li>
<li class="MsoNormal" style="color: black; line-height: normal; mso-list: l0 level1 lfo1; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; tab-stops: list .5in;"><span style="font-family: "Georgia",serif; font-size: 13.5pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">Chemical
sorption onto the aquifer material</span><span style="font-family: "Times New Roman",serif; font-size: 13.5pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></li>
<li class="MsoNormal" style="color: black; line-height: normal; mso-list: l0 level1 lfo1; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; tab-stops: list .5in;"><span style="font-family: "Georgia",serif; font-size: 13.5pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">Rectangular
patch source areas with user-specified concentration</span><span style="font-family: "Times New Roman",serif; font-size: 13.5pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></li>
</ul>
<p class="MsoNormal" style="line-height: normal; margin-bottom: 0in;"><b style="text-align: justify; text-indent: -0.25in;"><span style="font-family: "Times New Roman", serif; font-size: 14pt;"><br /></span></b></p><p class="MsoNormal" style="line-height: normal; margin-bottom: 0in;"><b style="text-align: justify; text-indent: -0.25in;"><span style="font-family: "Times New Roman", serif; font-size: 14pt;">What is the difference
between the ATRANS models in the ATRANS package?</span></b></p>
<p class="MsoNormal" style="line-height: normal; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; text-align: justify;"><span style="color: black; font-family: "Georgia",serif; font-size: 13.5pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">The main difference between
the different ATRANS models is in how they handle the source
concentrations <i>over time</i>. Taking from the <a href="https://transportstudio.com/downloads/TS-CHEM%20Solutions%20Features.pdf"><i><span style="color: blue;">Model Features Table</span></i></a> located in </span><i><span style="color: #ed7d31; font-family: "Georgia",serif; font-size: 13.5pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">Appendix
D of the TS-CHEM User Guide</span></i><span style="color: black; font-family: "Georgia",serif; font-size: 13.5pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";"> we can see that in the ATRANS models the
source can either be constant, decaying, or transient (time varying):</span><span style="color: black; font-family: "Times New Roman",serif; font-size: 13.5pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p>
<table border="0" cellpadding="0" cellspacing="0" class="MsoNormalTable" style="border-collapse: collapse; mso-padding-alt: 0in 0in 0in 0in; mso-yfti-tbllook: 1184;">
<tbody><tr style="mso-yfti-firstrow: yes; mso-yfti-irow: 0;">
<td rowspan="2" style="border: 1.5pt solid windowtext; padding: 0in 5.4pt; width: 93.5pt;" valign="top" width="125">
<p align="center" class="MsoNormal" style="line-height: normal; margin-bottom: 0in; mso-margin-top-alt: auto; text-align: center;"><span style="font-family: "Georgia",serif; font-size: 12pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">Solution Model</span><span style="font-family: "Times New Roman",serif; font-size: 12pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p>
</td>
<td colspan="3" style="border-left: none; border: 1.5pt solid windowtext; mso-border-left-alt: solid windowtext 1.5pt; padding: 0in 5.4pt; width: 280.5pt;" valign="top" width="374">
<p align="center" class="MsoNormal" style="line-height: normal; margin-bottom: 0in; mso-margin-top-alt: auto; text-align: center;"><span style="font-family: "Georgia",serif; font-size: 12pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">Source vs Time</span><span style="font-family: "Times New Roman",serif; font-size: 12pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p>
</td>
</tr>
<tr style="mso-yfti-irow: 1;">
<td style="border-bottom: 1.5pt solid windowtext; border-left: none; border-right: 1.5pt solid windowtext; border-top: none; padding: 0in 5.4pt; width: 93.5pt;" valign="top" width="125">
<p align="center" class="MsoNormal" style="line-height: normal; margin-bottom: 0in; mso-margin-top-alt: auto; text-align: center;"><b><span style="font-family: "Georgia",serif; font-size: 12pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">Constant Source</span></b><span style="font-family: "Times New Roman",serif; font-size: 12pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p>
</td>
<td style="border-bottom: 1.5pt solid windowtext; border-left: none; border-right: 1.5pt solid windowtext; border-top: none; padding: 0in 5.4pt; width: 93.5pt;" valign="top" width="125">
<p align="center" class="MsoNormal" style="line-height: normal; margin-bottom: 0in; mso-margin-top-alt: auto; text-align: center;"><b><span style="font-family: "Georgia",serif; font-size: 12pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">Decaying Source</span></b><span style="font-family: "Times New Roman",serif; font-size: 12pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p>
</td>
<td style="border-bottom: 1.5pt solid windowtext; border-left: none; border-right: 1.5pt solid windowtext; border-top: none; padding: 0in 5.4pt; width: 93.5pt;" valign="top" width="125">
<p align="center" class="MsoNormal" style="line-height: normal; margin-bottom: 0in; mso-margin-top-alt: auto; text-align: center;"><b><span style="font-family: "Georgia",serif; font-size: 12pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">Transient Source</span></b><span style="font-family: "Times New Roman",serif; font-size: 12pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p>
</td>
</tr>
<tr style="mso-yfti-irow: 2;">
<td style="border-top: none; border: 1.5pt solid windowtext; mso-border-top-alt: solid windowtext 1.5pt; padding: 0in 5.4pt; width: 93.5pt;" valign="top" width="125">
<p align="center" class="MsoNormal" style="line-height: normal; margin-bottom: 0in; mso-margin-top-alt: auto; text-align: center;"><b><span style="font-family: "Georgia",serif; font-size: 12pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">ATRANS1</span></b><span style="font-family: "Times New Roman",serif; font-size: 12pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p>
</td>
<td style="border-bottom: 1.5pt solid windowtext; border-left: none; border-right: 1.5pt solid windowtext; border-top: none; padding: 0in 5.4pt; width: 93.5pt;" valign="top" width="125">
<p align="center" class="MsoNormal" style="line-height: normal; margin-bottom: 0in; mso-margin-top-alt: auto; text-align: center;"><span style="font-family: "Georgia",serif; font-size: 12pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">X</span><span style="font-family: "Times New Roman",serif; font-size: 12pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p>
</td>
<td style="border-bottom: 1.5pt solid windowtext; border-left: none; border-right: 1.5pt solid windowtext; border-top: none; padding: 0in 5.4pt; width: 93.5pt;" valign="top" width="125">
<p align="center" class="MsoNormal" style="line-height: normal; margin-bottom: 0in; mso-margin-top-alt: auto; text-align: center;"><span style="font-family: "Georgia",serif; font-size: 12pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";"> </span><span style="font-family: "Times New Roman",serif; font-size: 12pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p>
</td>
<td style="border-bottom: 1.5pt solid windowtext; border-left: none; border-right: 1.5pt solid windowtext; border-top: none; padding: 0in 5.4pt; width: 93.5pt;" valign="top" width="125">
<p align="center" class="MsoNormal" style="line-height: normal; margin-bottom: 0in; mso-margin-top-alt: auto; text-align: center;"><span style="font-family: "Georgia",serif; font-size: 12pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";"> </span><span style="font-family: "Times New Roman",serif; font-size: 12pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p>
</td>
</tr>
<tr style="mso-yfti-irow: 3;">
<td style="border-top: none; border: 1.5pt solid windowtext; mso-border-top-alt: solid windowtext 1.5pt; padding: 0in 5.4pt; width: 93.5pt;" valign="top" width="125">
<p align="center" class="MsoNormal" style="line-height: normal; margin-bottom: 0in; mso-margin-top-alt: auto; text-align: center;"><b><span style="font-family: "Georgia",serif; font-size: 12pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">ATRANS2</span></b><span style="font-family: "Times New Roman",serif; font-size: 12pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p>
</td>
<td style="border-bottom: 1.5pt solid windowtext; border-left: none; border-right: 1.5pt solid windowtext; border-top: none; padding: 0in 5.4pt; width: 93.5pt;" valign="top" width="125">
<p align="center" class="MsoNormal" style="line-height: normal; margin-bottom: 0in; mso-margin-top-alt: auto; text-align: center;"><span style="font-family: "Georgia",serif; font-size: 12pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";"> </span><span style="font-family: "Times New Roman",serif; font-size: 12pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p>
</td>
<td style="border-bottom: 1.5pt solid windowtext; border-left: none; border-right: 1.5pt solid windowtext; border-top: none; padding: 0in 5.4pt; width: 93.5pt;" valign="top" width="125">
<p align="center" class="MsoNormal" style="line-height: normal; margin-bottom: 0in; mso-margin-top-alt: auto; text-align: center;"><span style="font-family: "Georgia",serif; font-size: 12pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">X</span><span style="font-family: "Times New Roman",serif; font-size: 12pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p>
</td>
<td style="border-bottom: 1.5pt solid windowtext; border-left: none; border-right: 1.5pt solid windowtext; border-top: none; padding: 0in 5.4pt; width: 93.5pt;" valign="top" width="125">
<p align="center" class="MsoNormal" style="line-height: normal; margin-bottom: 0in; mso-margin-top-alt: auto; text-align: center;"><span style="font-family: "Georgia",serif; font-size: 12pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";"> </span><span style="font-family: "Times New Roman",serif; font-size: 12pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p>
</td>
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<tr style="mso-yfti-irow: 4;">
<td style="border-top: none; border: 1.5pt solid windowtext; mso-border-top-alt: solid windowtext 1.5pt; padding: 0in 5.4pt; width: 93.5pt;" valign="top" width="125">
<p align="center" class="MsoNormal" style="line-height: normal; margin-bottom: 0in; mso-margin-top-alt: auto; text-align: center;"><b><span style="font-family: "Georgia",serif; font-size: 12pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">ATRANS3</span></b><span style="font-family: "Times New Roman",serif; font-size: 12pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p>
</td>
<td style="border-bottom: 1.5pt solid windowtext; border-left: none; border-right: 1.5pt solid windowtext; border-top: none; padding: 0in 5.4pt; width: 93.5pt;" valign="top" width="125">
<p align="center" class="MsoNormal" style="line-height: normal; margin-bottom: 0in; mso-margin-top-alt: auto; text-align: center;"><span style="font-family: "Georgia",serif; font-size: 12pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";"> </span><span style="font-family: "Times New Roman",serif; font-size: 12pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p>
</td>
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<p align="center" class="MsoNormal" style="line-height: normal; margin-bottom: 0in; mso-margin-top-alt: auto; text-align: center;"><span style="font-family: "Georgia",serif; font-size: 12pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";"> </span><span style="font-family: "Times New Roman",serif; font-size: 12pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p>
</td>
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<p align="center" class="MsoNormal" style="line-height: normal; margin-bottom: 0in; mso-margin-top-alt: auto; text-align: center;"><span style="font-family: "Georgia",serif; font-size: 12pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">X</span><span style="font-family: "Times New Roman",serif; font-size: 12pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p>
</td>
</tr>
<tr style="mso-yfti-irow: 5; mso-yfti-lastrow: yes;">
<td style="border-top: none; border: 1.5pt solid windowtext; mso-border-top-alt: solid windowtext 1.5pt; padding: 0in 5.4pt; width: 93.5pt;" valign="top" width="125">
<p align="center" class="MsoNormal" style="line-height: normal; margin-bottom: 0in; mso-margin-top-alt: auto; text-align: center;"><b><span style="font-family: "Georgia",serif; font-size: 12pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">ATRANS4</span></b><span style="font-family: "Times New Roman",serif; font-size: 12pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p>
</td>
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<p align="center" class="MsoNormal" style="line-height: normal; margin-bottom: 0in; mso-margin-top-alt: auto; text-align: center;"><span style="font-family: "Georgia",serif; font-size: 12pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";"> </span><span style="font-family: "Times New Roman",serif; font-size: 12pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p>
</td>
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<p align="center" class="MsoNormal" style="line-height: normal; margin-bottom: 0in; mso-margin-top-alt: auto; text-align: center;"><span style="font-family: "Georgia",serif; font-size: 12pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";"> </span><span style="font-family: "Times New Roman",serif; font-size: 12pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p>
</td>
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<p align="center" class="MsoNormal" style="line-height: normal; margin-bottom: 0in; mso-margin-top-alt: auto; text-align: center;"><span style="font-family: "Georgia",serif; font-size: 12pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">X</span><span style="font-family: "Times New Roman",serif; font-size: 12pt; mso-fareast-font-family: "Times New Roman";"><o:p></o:p></span></p>
</td>
</tr>
</tbody></table>
<p class="MsoNormal" style="line-height: normal; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; text-align: justify;"><span style="color: black; font-family: "Georgia",serif; font-size: 13.5pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">With this table in mind, we
can take a visual look at how these sources are represented with figures of
concentration over time from the ATRANS user manual and the </span><i><span style="color: #ed7d31; font-family: "Georgia",serif; font-size: 13.5pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">Model
Selection Tool</span></i><i><span style="color: black; font-family: "Georgia",serif; font-size: 13.5pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";"> </span></i><span style="color: black; font-family: "Georgia",serif; font-size: 13.5pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">in TS-CHEM:</span></p><p class="MsoNormal" style="line-height: normal; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; text-align: justify;"><span style="color: black; font-family: "Georgia",serif; font-size: 13.5pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";"><br /></span></p></div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgSClR8_P48urVe0HRJ3ybH0ksrSa86BaZ8XbVnCotZUs-Bo_IWHmP9-BLS1gXMP7V0QcCwBKBnapxPsdgik7d7EWD_iycnSGnzSFuWYxkUaYNp5VIoRWIeOg_4CsclZppbLrGIpgdkPINchdxLuI1rY5JIm2aYgISPx6F__3bP46sVCYPEEjhoiB4pww/s2145/Picture2.png" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="1250" data-original-width="2145" height="372" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgSClR8_P48urVe0HRJ3ybH0ksrSa86BaZ8XbVnCotZUs-Bo_IWHmP9-BLS1gXMP7V0QcCwBKBnapxPsdgik7d7EWD_iycnSGnzSFuWYxkUaYNp5VIoRWIeOg_4CsclZppbLrGIpgdkPINchdxLuI1rY5JIm2aYgISPx6F__3bP46sVCYPEEjhoiB4pww/w640-h372/Picture2.png" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><i><span style="font-family: "Times New Roman",serif; font-size: 12pt; line-height: 107%; mso-ansi-language: EN-US; mso-bidi-language: AR-SA; mso-fareast-font-family: "Times New Roman"; mso-fareast-language: EN-US;">Figure
2 - ATRANS model inputs: source concentrations over time<br /></span></i></td></tr></tbody></table><br /><div><p class="MsoNormal" style="line-height: normal; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; text-align: justify;"><span style="font-family: Georgia, serif; font-size: 13.5pt;">You may have noticed that
ATRANS3 and ATRANS4 both handle transient (time-variable) source
concentrations. The difference between these two models is in how the transient
concentration data is introduced to the model. ATRANS3 asks the user to input a
series of time-concentration pairs that define the source concentration history
(for example from measured values at certain points in time. The
software then creates discrete time steps with histograms that mimic the
continuous data, with the specified concentration point <u>at the center
of each histogram bar</u>. ATRANS4 asks the user to input a series of
time-concentration pairs, but for this model the user is specifying the
concentration level <u>at the start of a histogram bar</u> that
remains in effect until the next starting time and concentration is specified
(for example from historical knowledge of the starts of spills or releases at a
site source at certain points in time).</span><span style="font-family: "Times New Roman", serif; font-size: 13.5pt;"><o:p></o:p></span></p>
<p class="MsoNormal" style="line-height: normal; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; text-align: justify;"><span style="font-family: Georgia, serif; font-size: 13.5pt;"><br />
<!--[if !supportLineBreakNewLine]--><br />
<!--[endif]--></span><span style="font-family: "Times New Roman", serif; font-size: 13.5pt;"><o:p></o:p></span></p>
<p class="MsoNormal" style="line-height: normal; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto;"><b><span style="font-family: "Times New Roman", serif; font-size: 14pt;">What applications are
the ATRANS models best suited for?</span></b><span style="font-family: "Times New Roman", serif; font-size: 13.5pt;"><o:p></o:p></span></p>
<p class="MsoNormal" style="line-height: normal; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; text-align: justify;"><span style="font-family: Georgia, serif; font-size: 13.5pt;">As discussed in the
previous blog post “<i>TS-CHEM – The Swiss-Army Knife of Solute Transport
Modeling” </i>environmental professionals are often tasked with developing
conceptual site models (CSMs) that characterize the extent and behavior of
groundwater contaminant plumes, which the ATRANS models can assist with. In
particular, the ATRANS models are useful for representing sites where the
aquifer thickness is known or is believed to be bounded at a finite depth by an
impermeable base (</span><i><span style="color: #ed7d31; font-family: "Georgia",serif; font-size: 13.5pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">finite aquifer boundary</span></i><span style="font-family: Georgia, serif; font-size: 13.5pt;">)and where the investigator
has information on concentration at the downgradient edge of a source area (</span><i><span style="color: #ed7d31; font-family: "Georgia",serif; font-size: 13.5pt; mso-bidi-font-family: "Times New Roman"; mso-fareast-font-family: "Times New Roman";">patch
source</span></i><span style="font-family: Georgia, serif; font-size: 13.5pt;">). If only a single source concentration is known, and/or the
investigator wished to perform a conservative analysis, a constant source
ATRANS1 model can be applied. If the source is understood to be flushing and
depleting through time, an exponentially decaying ATRANS2 source model can be
applied. And if information is available on the changing history (both
increases and decreases) of source concentration with time, then an ATRANS3 or
ATRANS4 model can be applied, as described further below.</span><span style="font-family: "Times New Roman", serif; font-size: 13.5pt;"><o:p></o:p></span></p>
<p class="MsoNormal" style="line-height: normal; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; text-align: justify;"><span style="font-family: Georgia, serif; font-size: 13.5pt;"> </span><span style="font-family: "Times New Roman", serif; font-size: 13.5pt;"><o:p></o:p></span></p>
<p class="MsoNormal" style="line-height: normal; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; text-align: justify;"><span style="font-family: Georgia, serif; font-size: 13.5pt;">The <b>ATRANS1 model</b> is
useful for simulating scenarios that can be represented by constant
concentration sources. For instance, it can be used to support remedial design
by evaluating a conservative maximum plume extent and when the plume becomes
stable. It can also be used for regulatory compliance by conservatively
simulating potential receptor well impacts, or to assist with the delineation
of groundwater Classification Exception Areas (CEAs).</span><span style="font-family: "Times New Roman", serif; font-size: 13.5pt;"><o:p></o:p></span></p><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgxsUFuPdElwPnsLQECT3MjSbLdJUhesH4JMp-fCsrof-nlVKMEn2kFdo9SFylR3DCpQrtEZcQrPYR3YNdqxmzTE1-nCtM4ei3cH0FeMn3sRt2pZjftD4MqsuEY-xZd6v8Oizm44fosPytw1H6y51MWe7VelOz84O3g0N_Ias_EFLmPj346gU_VyxOidA/s624/Picture3.png" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="348" data-original-width="624" height="356" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgxsUFuPdElwPnsLQECT3MjSbLdJUhesH4JMp-fCsrof-nlVKMEn2kFdo9SFylR3DCpQrtEZcQrPYR3YNdqxmzTE1-nCtM4ei3cH0FeMn3sRt2pZjftD4MqsuEY-xZd6v8Oizm44fosPytw1H6y51MWe7VelOz84O3g0N_Ias_EFLmPj346gU_VyxOidA/w640-h356/Picture3.png" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><i><span style="font-family: "Times New Roman",serif; font-size: 12pt; line-height: 107%; mso-ansi-language: EN-US; mso-bidi-language: AR-SA; mso-fareast-font-family: "Times New Roman"; mso-fareast-language: EN-US;">Figure
3 - ATRANS1 solution showing maximum plume extent and stability for a benzene
plume with a constant source at 200ft, 600ft and 1000ft from the source</span></i></td></tr></tbody></table><br /><p class="MsoNormal" style="line-height: normal; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; text-align: justify;"><span style="font-family: Georgia, serif; font-size: 13.5pt;">The <b>ATRANS2 model</b> is
useful for simulating scenarios that can be represented by an exponential decay
in the source concentration and is one of three models in the TS-CHEM library
that can do so (the others being BIOSCREEN-AT and BIOSCREEN-AT NI). For
example, if an environmental professional wanted to simulate a scenario where a
benzene plume from a small spill source that is flushing and degrading with
time, they could use TS-CHEM and ATRANS2 with a decaying source to see how a
Monitored Natural Attenuation (MNA) remedy would reduce plume concentrations
over a ten-year period, particularly at locations close to the source:</span><span style="font-family: "Times New Roman", serif; font-size: 13.5pt;"><o:p></o:p></span></p><p class="MsoNormal" style="line-height: normal; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; text-align: justify;"></p><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjzZSsi098qdfaVIxGo7PwNIjSTZBWxhQJVIbJLenZdL6UMuTwk80QFYHyK03G4I3KOpOWOt73v-dc4fA51aKGNgxQ4SpaKyUSQcFCZ-yaXRa7oGKmOLPjGlSSWM0qXeKBZpFFWzScnGAEapg1noxZLbPoex0GDJEij01bBL3LlSJ_D2HJpDw5Cmury7g/s626/Picture4.png" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="381" data-original-width="626" height="390" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjzZSsi098qdfaVIxGo7PwNIjSTZBWxhQJVIbJLenZdL6UMuTwk80QFYHyK03G4I3KOpOWOt73v-dc4fA51aKGNgxQ4SpaKyUSQcFCZ-yaXRa7oGKmOLPjGlSSWM0qXeKBZpFFWzScnGAEapg1noxZLbPoex0GDJEij01bBL3LlSJ_D2HJpDw5Cmury7g/w640-h390/Picture4.png" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><i><span style="font-family: "Times New Roman",serif; font-size: 12pt; line-height: 107%; mso-ansi-language: EN-US; mso-bidi-language: AR-SA; mso-fareast-font-family: "Times New Roman"; mso-fareast-language: EN-US;">Figure
4 - ATRANS2 solution showing benzene plume concentrations after natural source
flushing and MNA at 200ft, 600ft and 1000ft from the source</span></i></td></tr></tbody></table><span style="font-family: Georgia, serif; font-size: 13.5pt;"><br /></span><p></p><p class="MsoNormal" style="line-height: normal; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; text-align: justify;"><span style="font-family: Georgia, serif; font-size: 13.5pt;">The </span><b style="font-family: Georgia, serif; font-size: 13.5pt;">ATRANS3</b><span style="font-family: Georgia, serif; font-size: 13.5pt;"> and </span><b style="font-family: Georgia, serif; font-size: 13.5pt;">ATRANS4</b><span style="font-family: Georgia, serif; font-size: 13.5pt;"> </span><b style="font-family: Georgia, serif; font-size: 13.5pt;">models</b><span style="font-family: Georgia, serif; font-size: 13.5pt;"> are
two of only four solutions in the TS-CHEM library that can account for
transient source concentrations (the others being AT123D-AT FT and AT123D-AT IT
which</span><span class="msoIns" style="font-family: Georgia, serif; font-size: 13.5pt;"><ins> </ins></span><span style="font-family: Georgia, serif; font-size: 13.5pt;">differ from the ATRANS models
in that AT123D-AT models employ mass flux specified sources in unbounded
aquifers). The ability to have transient source concentrations allows for the
simulation of intermittent single sources, multiple sources that occur at
different (or overlapping) times, and even termination of a source as would
result from a source removal remedy. In the example below, ATRANS4 was used to
simulate effects on a benzene plume as a result of remedial activities, where
the source was ceased after 180 days (to account for source removal as part of
active remediation) and MNA was able to reduce the concentration of the plume
to below 5 ug/L in the entire plume after just 2.5 years.</span></p><p class="MsoNormal" style="line-height: normal; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; text-align: justify;"></p><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhAiTrHLAi95XCIO7EVdwrhMKDEwVLt0UatDVY5weRXY-LG-AGaksSAueR6MYiRK4j_PojRfPovow4R-_6MNW_TflGsOQnGkZtx1Qg_anujjT1VbSsppqywj0knJKOAf6pE_acclf8hjj-r95UFjYksOCP9S5kdm0y6kijIIqNAsZhXdk4UlRPTx6O2Dg/s628/Picture5.png" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="366" data-original-width="628" height="372" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhAiTrHLAi95XCIO7EVdwrhMKDEwVLt0UatDVY5weRXY-LG-AGaksSAueR6MYiRK4j_PojRfPovow4R-_6MNW_TflGsOQnGkZtx1Qg_anujjT1VbSsppqywj0knJKOAf6pE_acclf8hjj-r95UFjYksOCP9S5kdm0y6kijIIqNAsZhXdk4UlRPTx6O2Dg/w640-h372/Picture5.png" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><i><span style="font-family: "Times New Roman",serif; font-size: 12pt; line-height: 107%; mso-ansi-language: EN-US; mso-bidi-language: AR-SA; mso-fareast-font-family: "Times New Roman"; mso-fareast-language: EN-US;">Figure
5 - ATRANS4 solution showing benzene plume concentrations after source
remediation and MNA at 200ft, 600ft and 1000ft from the source</span></i></td></tr></tbody></table><br /><p></p><p class="MsoNormal" style="line-height: normal; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; text-align: justify;"><b><span style="font-family: Georgia, serif; font-size: 13.5pt;">To summarize:</span></b><span style="font-family: Georgia, serif; font-size: 13.5pt;"> the
ATRANS family of models, which are built-in as part of the <a href="https://transportstudio.com/downloads/TS-CHEM%20Solutions%20Features.pdf"><i><span style="color: blue;">TS-CHEM solution library</span></i></a>, allow for flexible
representation of the source through time. The models assume a finite aquifer
boundary, so they are ideal for bounded aquifer models. The choice of model
will depend primarily on how the concentration of the simulated source changes
over time, as ATRANS models allow for sources that are constant, exponentially
decaying, or even time-variable. The ATRANS models allow environmental
professionals to evaluate plume characteristics for a variety of groundwater
plume transport scenarios.</span><span style="font-family: "Times New Roman", serif; font-size: 13.5pt;"><o:p></o:p></span></p><p class="MsoNormal" style="line-height: normal; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; text-align: justify;">
</p><p class="MsoNormal" style="line-height: normal; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; text-align: justify;"><span style="font-family: Georgia, serif; font-size: 13.5pt;">To learn more about
TS-CHEM, or to download a <a href="https://transportstudio.com/downloads.php"><span style="color: blue;">FREE DEMO VERSION</span></a> of the software, visit
the <a href="https://transportstudio.com/"><span style="color: blue;">TS-CHEM Website</span></a> today!</span><span style="font-family: "Times New Roman", serif; font-size: 13.5pt;"><o:p></o:p></span></p><p class="MsoNormal" style="line-height: normal; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; text-align: justify;"><span style="font-family: Georgia, serif; font-size: 13.5pt;"><br /></span></p></div><div><br /></div>flexAEMhttp://www.blogger.com/profile/06315034871207029515noreply@blogger.com0tag:blogger.com,1999:blog-2626672773765534936.post-15568119490382827702023-02-09T12:10:00.000-08:002023-02-09T12:10:32.667-08:00New Features in TS-CHEM Version 2022-3<p> <span style="font-family: inherit; font-size: 11pt;">TS-CHEM v2022-3 has some great new features, including new options for BIOSCREEN-AT, Dark Mode (Mac version) and the ability to double-click project files to open them. But some of the most powerful features center around the new chart controls. A brief overview of these new chart controls is included below.</span></p><p class="MsoNormal"><span style="font-family: inherit; font-size: 12pt; line-height: 17.12px;"><i><b>CHART AXIS CONTROLS</b></i><b><o:p></o:p></b></span></p><p><span style="font-family: inherit; font-size: 11pt; line-height: 15.6933px; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;">All three of the major chart types (C v t, Profile, and Contour) display axes; and so does the digitized concentration chart in the Concentration Inspector tool. In TS-CHEM v2022-3, the user can now control almost every aspect of the of these chart axes including:</span></p><ul><li><span style="font-family: inherit;">Major tick and label placement</span></li><li><span style="font-family: inherit;">Minor tick spacing</span></li><li><span style="font-family: inherit;">Chart grid lines</span></li><li><span style="font-family: inherit;">Custom axis title</span></li><li><span style="font-family: inherit;">Axis extent</span></li></ul><br /><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhdfSPS0pvP5HZTu1t8nJx-iycQO7ODwwGaI8BIxa1lK-Dhu-R6ZHuo1oBBIPwjsWZXKFnNI8w2S9mQYqe-8QpOCaEQlSQsBDTxMguKFUK8OqRy_Xk0opEiiF3jzIlk8JLlHaHbzdrgVjW_D8FTGaUzsnZOz9TjsP6tZZc81MzyTPRcZjtnlcLI6n4taA/s949/Figure%201.png" style="margin-left: 1em; margin-right: 1em;"></a><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><img alt="Custom Axis Settings" border="0" data-original-height="734" data-original-width="949" height="496" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhdfSPS0pvP5HZTu1t8nJx-iycQO7ODwwGaI8BIxa1lK-Dhu-R6ZHuo1oBBIPwjsWZXKFnNI8w2S9mQYqe-8QpOCaEQlSQsBDTxMguKFUK8OqRy_Xk0opEiiF3jzIlk8JLlHaHbzdrgVjW_D8FTGaUzsnZOz9TjsP6tZZc81MzyTPRcZjtnlcLI6n4taA/w640-h496/Figure%201.png" style="margin-left: auto; margin-right: auto;" title="Figure 1 - TS-CHEM Chart Axis Controls" width="640" /></td></tr><tr><td class="tr-caption" style="text-align: center;"><br /><i>Figure 1 - TS-CHEM Chart Axis Controls</i></td></tr></tbody></table><br /><div style="text-align: left;"><br /></div><div style="text-align: left;">These controls allow for the creation of better-looking data plots.</div><div style="text-align: left;"><br /></div><div style="text-align: left;"><br /></div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhrgXM0UBjUOpSqBmE1eubsqT7J28tEJbA1aKghq1ma8wDDbbv0kDZLafp7RqwJrBj-yZpjBDakH7Hpi35cvS2MXFMXwxE7o5MqSLoRnSm3hANNnfkhMaY0zAx4tcrmdvaaUN7r3HkWw42HToHYuNQG_UMnO7hQ62pkr7_fihhHqgCkWOaLFFEcPOhSjA/s754/Figure%202.png" style="margin-left: auto; margin-right: auto;"><img alt="Trichloroethene Concentration vs Time" border="0" data-original-height="464" data-original-width="754" height="394" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhrgXM0UBjUOpSqBmE1eubsqT7J28tEJbA1aKghq1ma8wDDbbv0kDZLafp7RqwJrBj-yZpjBDakH7Hpi35cvS2MXFMXwxE7o5MqSLoRnSm3hANNnfkhMaY0zAx4tcrmdvaaUN7r3HkWw42HToHYuNQG_UMnO7hQ62pkr7_fihhHqgCkWOaLFFEcPOhSjA/w640-h394/Figure%202.png" title="Figure 2 - TS-CHEM Concentration vs. Time Data Plot" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><i>Figure 2 - TS-CHEM Concentration vs. Time Data Plot</i></td></tr></tbody></table><br /><div style="text-align: left;"><br /></div><div style="text-align: left;">And, in the case of the axis extent controls, they allow the user to zoom in on a portion of the chart to better examine data concentrations or trends.</div><br /><div style="text-align: left;"><br /></div><br /><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhdfSPS0pvP5HZTu1t8nJx-iycQO7ODwwGaI8BIxa1lK-Dhu-R6ZHuo1oBBIPwjsWZXKFnNI8w2S9mQYqe-8QpOCaEQlSQsBDTxMguKFUK8OqRy_Xk0opEiiF3jzIlk8JLlHaHbzdrgVjW_D8FTGaUzsnZOz9TjsP6tZZc81MzyTPRcZjtnlcLI6n4taA/s949/Figure%201.png" style="margin-left: 1em; margin-right: 1em;"></a></div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjm7La8TBylLJd0tPewbhvjZWrHTO8ap3VkdqFS-EFJur_bX3r7cZ7vAncD64C7MklXatfplJjIMQDXvbIpvdJ8zgMJN5xu1rLUdQ3xsaDD7mCgrfzEJKzNsLTe9RbURQxIi05wbhbW9fLxAAAQLX2jubvZKK2ffo6Se5Vwm8TJMA88tmqdY__Whl1g2A/s734/Figure%203.png" style="margin-left: auto; margin-right: auto;"><img alt="TCE Concentration vs. Time Data Plot" border="0" data-original-height="452" data-original-width="734" height="394" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjm7La8TBylLJd0tPewbhvjZWrHTO8ap3VkdqFS-EFJur_bX3r7cZ7vAncD64C7MklXatfplJjIMQDXvbIpvdJ8zgMJN5xu1rLUdQ3xsaDD7mCgrfzEJKzNsLTe9RbURQxIi05wbhbW9fLxAAAQLX2jubvZKK2ffo6Se5Vwm8TJMA88tmqdY__Whl1g2A/w640-h394/Figure%203.png" title="Figure 3 - Zoom-in of TS-CHEM Data Plot" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><i>Figure 3 - Zoom-in of TS-CHEM Data Plot</i></td></tr></tbody></table><br /><br /><div><b><i>CONTOUR CHART CONTOLS</i></b></div><div><b><i><br /></i></b></div><div>Contour charts now have a second set of controls (in addition to the axis controls) that allow easy formatting of the contour intervals and the type of contour chart used to display the data.</div><div><br /></div><div>Intervals controls allow the user to accept the automatic TS-CHEM contouring, or specify Regular Intervals (min, max, and interval), or select Custom Contours to customize the spacing and color of the contour display. </div><div><br /></div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjB3PWJZJPGFlAZoklXixERaCckYtQfuFDbBo9etY_4Cm-GtSZgmgYe9sK9LcIbJasgR30KBSjGvoKuJQw2AOUNySqxxd0p_7TYfm7szhvlGsjtCCIilWX_XpbEky8inaRTRbJk0oFJsse35Cj7v5IdKTdIYm9RP6mWrcEWsCnCy7aTW5jGe0Gkc4ioEQ/s1007/Figure%204.png" style="margin-left: auto; margin-right: auto;"><img alt="Custom Groundwater Plume Contour Settings" border="0" data-original-height="779" data-original-width="1007" height="496" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjB3PWJZJPGFlAZoklXixERaCckYtQfuFDbBo9etY_4Cm-GtSZgmgYe9sK9LcIbJasgR30KBSjGvoKuJQw2AOUNySqxxd0p_7TYfm7szhvlGsjtCCIilWX_XpbEky8inaRTRbJk0oFJsse35Cj7v5IdKTdIYm9RP6mWrcEWsCnCy7aTW5jGe0Gkc4ioEQ/w640-h496/Figure%204.png" title="Figure 4 - TS-CHEM Contour Charts - Custom Settings" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><br /><i>Figure 4 - TS-CHEM Contour Charts - Custom Settings</i></td></tr></tbody></table><br /><br /><div>The value specified in the Boundary field (50 in the example above) serves as a plume cutoff concentration, and the plume image is transparent for concentrations below the Boundary value (see below). This makes it very easy to create a bounded plume to place on digital map using the Map Overlay feature.</div><div><br /></div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi-wD8CTjlybCvmT6NRqfKdYh7pdSsK8zM-gCQXMtG7cwq_9qClW52gxHR9sEzWOAr8gf1Qfz3r9o_tbbPxtIXgwRaOcDrhfUcqm_bu5Zl4tSBgIYjmJ9sLX8eVe5qVo4QbqQZy1ZCnEPwO9VPeecxc60usUb9EJBlLtOtQU7AJ6fSFVeK8AI1e7npXBw/s926/Figure%205.png" style="margin-left: auto; margin-right: auto;"><img alt="Modeled Trichloroethene (TCE) Plume in Groundwater" border="0" data-original-height="570" data-original-width="926" height="394" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi-wD8CTjlybCvmT6NRqfKdYh7pdSsK8zM-gCQXMtG7cwq_9qClW52gxHR9sEzWOAr8gf1Qfz3r9o_tbbPxtIXgwRaOcDrhfUcqm_bu5Zl4tSBgIYjmJ9sLX8eVe5qVo4QbqQZy1ZCnEPwO9VPeecxc60usUb9EJBlLtOtQU7AJ6fSFVeK8AI1e7npXBw/w640-h394/Figure%205.png" title="Figure 5 - TCE Plume Contour Chart - Plume Bounded at 50 ppb" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><br /><i>Figure 5 - TCE Plume Contour Chart - Plume Bounded at 50 ppb</i></td></tr></tbody></table><br /><br /><div>Additionally, the Style for a contour chart can be selected from a dropdown menu containing the following options:</div><div><ul><li>Fill – Color</li><li>Fill – Grayscale</li><li>Lines Only – Color</li><li>Lines Only – Grayscale</li><li>Lines Only – Black<br /></li></ul>An example of a Lines Only – Color contour chart is shown below.</div><div><br /></div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh3baUKq38PdVviUa7jb48B-D19ynrY7V5FtuYsisqJgco3eOwvkxyw0zmi7Wr31iVTc6QJ1uOGnJtRt82usMUfiqRxGqTFNeW6XRdyOc2Lw5IsvDl5XjRMpOXxkGEvoLvldkuiwpUwG37UXahwyZ4oMcK7t9l2fhtLH-0Ci7GhB8zaAoybtG3o3MMStw/s1217/Figure%206.png" style="margin-left: auto; margin-right: auto;"><img alt="Modeled Trichloroethene Plume in Groundwater" border="0" data-original-height="819" data-original-width="1217" height="430" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh3baUKq38PdVviUa7jb48B-D19ynrY7V5FtuYsisqJgco3eOwvkxyw0zmi7Wr31iVTc6QJ1uOGnJtRt82usMUfiqRxGqTFNeW6XRdyOc2Lw5IsvDl5XjRMpOXxkGEvoLvldkuiwpUwG37UXahwyZ4oMcK7t9l2fhtLH-0Ci7GhB8zaAoybtG3o3MMStw/w640-h430/Figure%206.png" title="Figure 6 - TCE Plume Contour Chart Displaying Lines Only - Plume Bounded at 50 ppb" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><br /><i>Figure 6 - TCE Plume Contour Chart Displaying Lines Only - Plume Bounded at 50 ppb </i></td></tr></tbody></table><br /><br /><div><div>These sets of controls, tailored to each of the different chart types, provide the tools needed to produce report- or presentation-ready graphics from your TS-CHEM plume transport modeling analyses.</div><div>To learn more about the <a href="https://transportstudio.com/software.php" target="_blank"><span style="color: #2b00fe;">new features</span></a> TS-CHEM v2022-3, or to download a <a href="https://transportstudio.com/pricing.php" target="_blank"><span style="color: #2b00fe;">FREE DEMO VERSION</span></a> of the software, visit the <a href="https://transportstudio.com/"><span style="color: #2b00fe;">TS-CHEM Website</span></a> today</div><div><br /></div><br /><div><br /><br /><br /><div><br /></div></div></div>flexAEMhttp://www.blogger.com/profile/06315034871207029515noreply@blogger.com0tag:blogger.com,1999:blog-2626672773765534936.post-45401101956848518762022-12-09T14:21:00.003-08:002022-12-12T10:13:55.751-08:00TS-CHEM - The Swiss-Army Knife of Solute Transport Modeling<p><b><i>Understanding Plume Movement at a Site</i></b></p><p>Environmental professionals are often tasked with investigating contaminated sites to understand the nature and extent of contamination in groundwater, and select an appropriate remedy that will effectively limit migration of impacted groundwater, treat it, and prevent groundwater plumes from reaching sensitive receptors. To do this, a sound conceptual site model (CSM) is necessary, which requires not only collection of adequate site data (including groundwater sampling data, water level elevation data, and information on site hydrogeologic conditions) and application of professional judgement, but also the use of data analysis tools and techniques that allow for a better understanding of the fate and transport of contaminants in groundwater.</p><p><b><i>Plume Modeling Tools</i></b></p><p>Although there are a number of analytical solute transport modeling tools that are freely available (such as the Pennsylvania Department of Environmental Protection’s Quick Domenico Model, and the United States Environmental Protection Agency’s BIOCHLOR model), these tools are relatively simple, and while they serve as great screening level tools, they are typically limited in how they represent site source conditions (e.g., as a constant concentration “patch” source) and in how they present results (often only a simple concentration versus distance curve with no plume contour plot). </p><p><b><i>Better Representation of the Contaminant Source</i></b></p><p>Simplified source condition models may be adequate for some site analyses (e.g. for conservative screening analyses) but, in reality, sources of groundwater contamination are usually more complex, and may need to be represented in a different way. Does this mean that as an environmental professional, you have to plan on additional budget for the development of a more sophisticated 3D numerical fate and transport model, or forgo any modeling analyses altogether due to budget and time constraints? The answer is no. </p><p>As environmental professionals ourselves who routinely conduct solute transport modeling analyses as part of our work, we wanted to develop a tool that included the many analytical solutions that have been developed over the last several decades – essentially, a “Swiss Army Knife” of solute transport modeling. So, we developed TS-CHEM to include a library of <a href="https://transportstudio.com/downloads/TS-CHEM%20Solutions%20Features.pdf" target="_blank"><span style="color: #2b00fe;">More than 30 <span> Analytical Solutions</span></span></a>, each with different capabilities, including how they represent contaminant sources. The various solutions within the TS-CHEM library are capable of representing sources as points, lines, volumes, and patches (including rectangular and circular geometries). Additionally, source concentrations can be continuous, constant, decaying, and/or transient. This provides a great deal of flexibility in allowing for the selection of source configurations that best represent site conditions. </p><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhx9nKLuJO47ejaAbe7AJi8xyCzTRCT5ErfacC8kOJ3rjrLKynIu3AFuhXqmrrXNXwXYXIS7lmDdrR4C3jxDYp4Vvud6dibPyX4SPqY6VeJeaQB4J4QH1NYHnja7klOuiuxGX9_YqO6jPfbsWMsmgDFfmdL2FlUjt4f1WmKccVgr8FuK8B1J4HN4DZWZA/s1919/Figure%201.png" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="1454" data-original-width="1919" height="303" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhx9nKLuJO47ejaAbe7AJi8xyCzTRCT5ErfacC8kOJ3rjrLKynIu3AFuhXqmrrXNXwXYXIS7lmDdrR4C3jxDYp4Vvud6dibPyX4SPqY6VeJeaQB4J4QH1NYHnja7klOuiuxGX9_YqO6jPfbsWMsmgDFfmdL2FlUjt4f1WmKccVgr8FuK8B1J4HN4DZWZA/w400-h303/Figure%201.png" width="400" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><br /><i>Figure 1 - TS-CHEM Source Geometry Capabilities</i></td></tr></tbody></table><br /><br /><div><b><i>Better Presentation of Analysis Results</i></b></div><div><b><i><br /></i></b></div><div>In addition to having only limited capabilities with regard to source representation, many freely available solute transport modeling tools also lack the ability to analyze and interpret modeling results – often only showing simple plots of concentrations vs. time/distance. As environmental professionals, there are typically other information needs that arise when developing our CSMs and planning remedies. For example, what volume of water is impacted? What is the estimated contaminated mass within the plume? What is the mass flux through a segment of the plume? Based on our experience in performing solute transport modeling analyses to assist with CSM development and remedy planning (and having these kinds of questions come up), we built in a whole suite of analysis tools into TS-CHEM, including tools that allow for the estimation of:</div><div><br /></div><div>•<span style="white-space: pre;"> </span>Plume area</div><div>•<span style="white-space: pre;"> </span>Plume volume (including total aquifer volume, and water within aquifer materials)</div><div>•<span style="white-space: pre;"> </span>Plume mass</div><div>•<span style="white-space: pre;"> </span>Average plume concentration</div><div>•<span style="white-space: pre;"> </span>Plume mass flux</div><br /><div><br /></div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgR9J_WOJa2w87bSKELbsOseRbErWTHexbJgWZ31OEd8jrBVYjUv3SvzsCvHQwCbNwItshUbPyWPaCv7zOQt51y2E6tI67daFPsGt7MwFjrsvL6gK67svxVZqgQ3o8FFCyZRoRhk_rYQkqibPLRrhUUL0xSfvFp0lTDuuL_Wg6kjKxf84Lg8gyi3zYEWQ/s4088/Figure%202.png" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="1726" data-original-width="4088" height="270" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgR9J_WOJa2w87bSKELbsOseRbErWTHexbJgWZ31OEd8jrBVYjUv3SvzsCvHQwCbNwItshUbPyWPaCv7zOQt51y2E6tI67daFPsGt7MwFjrsvL6gK67svxVZqgQ3o8FFCyZRoRhk_rYQkqibPLRrhUUL0xSfvFp0lTDuuL_Wg6kjKxf84Lg8gyi3zYEWQ/w640-h270/Figure%202.png" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><br /><i>Figure 2 - TS-CHEM Plume Mass Calculator Analysis Tool</i></td></tr></tbody></table><br /><div><div>These TS-CHEM analysis tools allow environmental professionals to quickly and easily obtain key information about groundwater plume characteristics, without having to export data and analyze it in another software program (or programs) – another reason why TS-CHEM is the “Swiss Army Knife” of solute transport modeling!</div><div><br /></div><div>To learn more about <a href="https://transportstudio.com/"><span style="color: #2b00fe;">TS-CHEM</span></a>, or to download a <a href="https://transportstudio.com/pricing.php"><span style="color: #2b00fe;">FREE DEMO VERSION</span></a> of the software, visit the <a href="https://transportstudio.com/"><span style="color: #2b00fe;">TS-CHEM Website</span></a> today!</div></div><div><br /></div>flexAEMhttp://www.blogger.com/profile/06315034871207029515noreply@blogger.com0tag:blogger.com,1999:blog-2626672773765534936.post-15104167657293036852022-08-17T13:11:00.000-07:002022-08-17T13:11:14.726-07:00Visualize Your Modeled Plume with the New Map Overlay Feature<p>One of the most exciting new additions in the latest release of TS-CHEM (version 2022-2, which can be downloaded<u> <a href="https://transportstudio.com/pricing.php#1" target="_blank"><span style="color: #2b00fe;">HERE</span></a></u>) is the new “Map Overlay” feature. After a concentration contour chart has been created and displayed, the TS-CHEM Map Overlay tool can be used to visualize the calculated plume. The plume is displayed as an overlay on a digital map, with the source located at the user-entered address. Attributes of the map and the plume can be modified using various Map Overlay controls.</p><p>Using the new Map Overlay is simple. Once you have generated a concentration contour chart and adjusted the plume contours to your preferred bounds, simply click on the “Map Overlay” button just above the plume contour chart (see <b><i>Figure 1</i></b>).</p><p><br /></p><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgF0gwamiGAY5Hrct_OWYzH7pCGC5pMcp0CJje1F-VBZaezp59xd9TIQjBmodTsB7kYiMK2mHmH4Tw11e2StydFlQhvgK_Ulmx3tPgh4isyeuOLcKqXT6Heb3DGbmFTM_4Ux3RN1FguhKiv3jqoGcANkl9Qtw2urW27u3yidhaSq9OxElKVyFm4jE3Ucg/s2332/TSC_Fig%201.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="1332" data-original-width="2332" height="366" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgF0gwamiGAY5Hrct_OWYzH7pCGC5pMcp0CJje1F-VBZaezp59xd9TIQjBmodTsB7kYiMK2mHmH4Tw11e2StydFlQhvgK_Ulmx3tPgh4isyeuOLcKqXT6Heb3DGbmFTM_4Ux3RN1FguhKiv3jqoGcANkl9Qtw2urW27u3yidhaSq9OxElKVyFm4jE3Ucg/w640-h366/TSC_Fig%201.png" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><i>Figure 1 - Plume Contour Chart</i></td></tr></tbody></table><br /><p class="MsoNormal">A popup will appear that allows you to enter an address, and
then click “Go”. For example, entering
“Statue of Liberty NY” will display your contoured plume with its origin at the
Statue of Liberty (as shown in <b><i>Figure 2</i></b> below).<o:p></o:p></p><p class="MsoNormal"><br /></p><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjLv3VGONSE3bFjxGhp0eBbZ-71ztiXP-Wz5APBKQSGr4Q_JPXGYRJ2gxJS4wcsvL7BiXf0MoVf--5NsYCsS4ETTQKADZqRvGyflKKJjXR1emSpwI94aBpH6KiYWhxBvYwfR--Sw4SPsuLgdQbaVUBUYaorZeDlFs2CEhpPvH4OQ_vq3Rnags1k87FxQA/s624/TSC_Fig%202.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="341" data-original-width="624" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjLv3VGONSE3bFjxGhp0eBbZ-71ztiXP-Wz5APBKQSGr4Q_JPXGYRJ2gxJS4wcsvL7BiXf0MoVf--5NsYCsS4ETTQKADZqRvGyflKKJjXR1emSpwI94aBpH6KiYWhxBvYwfR--Sw4SPsuLgdQbaVUBUYaorZeDlFs2CEhpPvH4OQ_vq3Rnags1k87FxQA/s16000/TSC_Fig%202.png" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><i>Figure 2 – Example Map Overlay with Plume Contour Chart Originating at Statue of Liberty<br /><br /><br /></i></td></tr></tbody></table><br /><p class="MsoNormal">Once your contour plot is overlayed on your site of
interest, you can use the “Map”, “Plume”, “Overlay”, and “Metrics” tabs within
the Map Overlay window to modify and customize your overlay as desired. Specifically, these tabs can be used to do
the following</p><p class="MsoNormal"></p><ul style="text-align: left;"><li>Change the desired map style (e.g., satellite)
zoom in or out, and access the plume and legend formatting controls (Map tab)</li><li><span style="text-indent: -0.25in;">Modify plume origin, rotate your plume, adjust
plume transparency, and display model grid extent if desired (Plume tab)</span></li><li><span style="text-indent: -0.25in;">Modify the many features of the overlay map
image, including Title, Legend, Scale (Overlay tab)</span></li><li><span style="text-indent: -0.25in;">Examine information related to the map location
(latitude and longitude), current zoom level, etc. (Metrics tab)</span></li></ul><div style="text-indent: -24px;"><br /></div><p></p><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjTt_pmlkPwcy9OcbhVLh8JnRc7cDFJ7BdX-5kqLqRrXKUQOgYG6QXhrNyDab5nc_E1uZzgHmABgG5FsB0eN8Vn_pRk5ITHoeT7HMDx2oIroYDIAZMNKcmiCZYn0d-u4foifLLzqjTOO0YnZxX5DgF07_BqA0lWJaRWYVcT6MzgLkagixNj0oLLlieAIg/s624/TSC_Fig%203.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="337" data-original-width="624" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjTt_pmlkPwcy9OcbhVLh8JnRc7cDFJ7BdX-5kqLqRrXKUQOgYG6QXhrNyDab5nc_E1uZzgHmABgG5FsB0eN8Vn_pRk5ITHoeT7HMDx2oIroYDIAZMNKcmiCZYn0d-u4foifLLzqjTOO0YnZxX5DgF07_BqA0lWJaRWYVcT6MzgLkagixNj0oLLlieAIg/s16000/TSC_Fig%203.png" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><i>Figure 3 – Customized Map Overlay ready for export</i></td></tr></tbody></table><br /><div>Once you have adjusted and customized your map to your liking, simply click the “Save Image” button, in the lower right corner of any of the Map Overlay tabs, which allows you to export the Map Overlay image as a .PNG or .JPEG (.JPG) file (which can then be used to incorporate into a report figure, slide deck, etc.)</div><div><br /></div><div>In addition to the new Map Overlay feature, several other updates and improvements have been incorporated into TS-CHEM version 2022-2, including:</div><div><ul style="text-align: left;"><li>The addition of data charting to the Concentration Inspector tool</li><li>The addition of Output Times information to the Solve window (to indicate when requested output may require long solve times)</li><li>Enhanced solve speeds for several codes, including ATRANS (1, 2, 3, and 4), BIOSCREEN-AT, and AT123D-AT</li><li>Enhanced speeds for contour chart drawing and project save files</li><li>Minor bug fixes</li></ul><br /></div><div>To take advantage of these updates and improvements and test out the new Map Overlay feature, head over to the<u> <a href="https://transportstudio.com/pricing.php"><span style="color: #2b00fe;">TS-CHEM Website</span></a></u> to download version 2022-2 today! </div><div><br /></div><br /><p class="MsoListParagraphCxSpLast" style="mso-list: l0 level1 lfo1; text-indent: -.25in;"><o:p></o:p></p><div><br /></div>flexAEMhttp://www.blogger.com/profile/06315034871207029515noreply@blogger.com0tag:blogger.com,1999:blog-2626672773765534936.post-71944428264524982842022-06-05T15:47:00.002-07:002022-06-05T15:47:47.050-07:00TS-CHEM Version 2022-1 Now Available!<p>We are pleased to announce the release of TS-CHEM version 2022-1! Key updates in this new version include the following:</p><p></p><ul style="text-align: left;"><li>Easier data entry controls</li><li>The addition of a concentration cursor inspector tool to allow for examination of concentrations at points of interest within the modeled plume (which can be copied to a data pane and then and then be exported for analysis using other software (e.g., Microsoft Word or Excel))</li><li>Labeling of concentration contours on plume contour charts</li><li>Minor bug fixes</li></ul><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEiT4dNf64GQL32516gpnI3yCIfBvYMaKYliHcJs-SPDB0TwsfTCHLPk1U9eJT0jr4fgwHNTZ2vFqFKyVVsVmrmPkZHFKoqfvKMYsiZIPLqRgX3-e2HcrIZGQ9MHfhk4Gw7ixiZOHkus4juiJ2WaYClpfgHaSZrdLbY7kfuN6yeDXk-6rYRG7G8qYdw8rw" style="margin-left: 1em; margin-right: 1em;"><img alt="" data-original-height="413" data-original-width="741" height="357" src="https://blogger.googleusercontent.com/img/a/AVvXsEiT4dNf64GQL32516gpnI3yCIfBvYMaKYliHcJs-SPDB0TwsfTCHLPk1U9eJT0jr4fgwHNTZ2vFqFKyVVsVmrmPkZHFKoqfvKMYsiZIPLqRgX3-e2HcrIZGQ9MHfhk4Gw7ixiZOHkus4juiJ2WaYClpfgHaSZrdLbY7kfuN6yeDXk-6rYRG7G8qYdw8rw=w640-h357" width="640" /></a></div><div class="separator" style="clear: both; text-align: center;"><i><span style="font-size: x-small;">Figure 1: Labeling of Concentration Contours</span></i></div><div class="separator" style="clear: both; text-align: center;"><i><span style="font-size: x-small;"><br /></span></i></div><div class="separator" style="clear: both; text-align: center;"><div class="separator" style="clear: both; font-size: small; font-style: italic; text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEjZKI_SXYF-n3gHfEHUEXRQDe85RZQJOywirLCykDinX25NhvTPNCyge1elpxQxMK0R9JAT6ZBhDup71upee1DsDxBnEuKIMgLnH2GWPaQtbAVBLhxbkfZaBG4lMv_IxMntPuE_eX_Ym7sV-0LmZ2rKyt21NHDD57jpPoyjzCTyzYVDTgY5id88viCfAg" style="margin-left: 1em; margin-right: 1em;"><img alt="" data-original-height="607" data-original-width="927" height="421" src="https://blogger.googleusercontent.com/img/a/AVvXsEjZKI_SXYF-n3gHfEHUEXRQDe85RZQJOywirLCykDinX25NhvTPNCyge1elpxQxMK0R9JAT6ZBhDup71upee1DsDxBnEuKIMgLnH2GWPaQtbAVBLhxbkfZaBG4lMv_IxMntPuE_eX_Ym7sV-0LmZ2rKyt21NHDD57jpPoyjzCTyzYVDTgY5id88viCfAg=w640-h421" width="640" /></a></div><div class="separator" style="clear: both; text-align: center;"><div class="separator" style="clear: both; font-size: small; font-style: italic; text-align: center;">Figure 2 – Concentration Cursor Inspector Tool Data Pane</div><div class="separator" style="clear: both; font-size: small; font-style: italic; text-align: center;"><br /></div><div class="separator" style="clear: both; font-size: small; font-style: italic; text-align: left;"><br /></div><div class="separator" style="clear: both; text-align: left;">Concentration contour labels can be displayed or hidden, and their font type, size, and color are user selectable.</div><div class="separator" style="clear: both; text-align: left;"><br /></div><div class="separator" style="clear: both; text-align: left;">New data controls were designed to prevent inadvertent entry of extraneous spaces or item separators that in some cases interfered with the proper calculation and display of model results.</div><div class="separator" style="clear: both; text-align: left;"><br /></div><div class="separator" style="clear: both; text-align: left;">In addition, the new Concentration Inspector tool provides the user with a way of analyzing calculated plume concentrations. Concentration values on any selected output plane can be mapped and inspected using the cursor to examine concentration trends in the plume. X, Y, Z, C data at selected locations can be saved to the inspector list, and then exported for cross-section plotting in Excel of other graphic software.</div><div style="font-size: small; font-style: italic;"><br /></div></div><div style="text-align: left;">Visit the <b><span style="color: #2b00fe;"><a href="https://transportstudio.com/pricing.php" target="_blank">Transport Studio Website</a> </span></b>today to download the latest version of TS-CHEM!</div><br /></div><br /><br /><p></p>flexAEMhttp://www.blogger.com/profile/06315034871207029515noreply@blogger.com0tag:blogger.com,1999:blog-2626672773765534936.post-70282808912502079402021-10-19T13:51:00.002-07:002021-10-21T11:03:56.828-07:00A Quick Start to Exploring TS-CHEM<p> </p><h1 class="page_header" style="background-color: white; box-sizing: border-box; color: #347ab1; font-family: Lato, sans-serif; font-size: 24px; line-height: 1.2; margin-bottom: 0.5rem; margin-top: 0px;">Quick Start Guide to TS-CHEM</h1><div><br /></div><div><span style="background-color: white; color: #707070; font-family: arial; font-size: 18px;">Within minutes, you can run your own solute transport models using TS-CHEM! To start using and discovering what TS-CHEM can do, follow these simple instructions:</span></div><div><span style="background-color: white; color: #707070; font-family: arial; font-size: 18px;"><br /></span></div><div><span style="font-family: arial;"><span face="Lato, sans-serif" style="background-color: white; color: #707070; font-size: 18px;">1. Navigate to </span><span face="Lato, sans-serif"><span style="font-size: 18px;"><span style="color: #707070;">the TS-CHEM website </span><a href="https://transportstudio.com/purchase.php"><span style="color: #2b00fe;">purchase page</span></a><span style="color: #707070;"> and click on the blue "Try TS-CHEM Demo" button.</span></span></span></span></div><div><span face="Lato, sans-serif" style="color: #707070;"><span style="font-family: arial; font-size: 18px;"><br /></span></span></div><div><span face="Lato, sans-serif" style="color: #707070;"><span style="font-family: arial; font-size: 18px;">2. Select your operating system and click "Checkout." (There is no charge for the demo, and no credit card information is required.) After entering some basic information, you will receive an email with a link to download TS-CHEM, a quick start guide, and a more detailed user manual.</span></span></div><div><span face="Lato, sans-serif" style="color: #707070;"><span style="font-family: arial; font-size: 18px;"><br /></span></span></div><div><span face="Lato, sans-serif" style="color: #707070;"><span style="font-family: arial; font-size: 18px;">3. Once you download and install the software, launch TS-CHEM to enter the demo version of the software. </span></span></div><div><span face="Lato, sans-serif" style="color: #707070;"><span style="font-family: arial; font-size: 18px;"><br /></span></span></div><div><span face="Lato, sans-serif" style="color: #707070;"><span style="font-family: arial; font-size: 18px;">4. Download and open the Quick Start Guide PDF, which will take you through the process of creating a single source model as well as a 2-source model that generates a commingled contaminant plume.</span></span></div><div><span face="Lato, sans-serif" style="color: #707070;"><span style="font-family: arial; font-size: 18px;"><br /></span></span></div><div><span face="Lato, sans-serif" style="color: #707070;"><span style="font-family: arial; font-size: 18px;">5. By the end of the Quick Start Guide (which should take about 10 minutes), you will be able to produce the two-source solute transport model shown below:</span></span></div><div><span face="Lato, sans-serif" style="color: #707070;"><div class="separator" style="clear: both; text-align: center;"><br /></div><span style="font-size: 18px;"><br /></span></span><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/a/AVvXsEjqOBaxgvN77aGRxziOkBLz6Py0IDvnlMuI3903F1UGMGJgCm5OGVLUjtfEqM9uwHexaPcUWw_J1G7i663Oe9GEollb4b_X7uyu1q-AEWiblRuz1RATUqlTDjosUkGCt3vTZxIwWDy9SERQUGVZoJT_-cgcguxPfyPKgGDNIWglUUXKcV0jN1iwh1dNDg=s927" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="521" data-original-width="927" height="247" src="https://blogger.googleusercontent.com/img/a/AVvXsEjqOBaxgvN77aGRxziOkBLz6Py0IDvnlMuI3903F1UGMGJgCm5OGVLUjtfEqM9uwHexaPcUWw_J1G7i663Oe9GEollb4b_X7uyu1q-AEWiblRuz1RATUqlTDjosUkGCt3vTZxIwWDy9SERQUGVZoJT_-cgcguxPfyPKgGDNIWglUUXKcV0jN1iwh1dNDg=w439-h247" width="439" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">A 2-source Solute Transport Model of Trichloroethene (TCE) Solved using ATRANS1 </td></tr></tbody></table><div class="separator" style="clear: both; text-align: center;"><br /></div><div class="separator" style="clear: both; text-align: left;"><br /></div><br /></div>flexAEMhttp://www.blogger.com/profile/06315034871207029515noreply@blogger.com0tag:blogger.com,1999:blog-2626672773765534936.post-87247390400857427352021-10-15T08:58:00.001-07:002021-10-18T10:32:36.370-07:00Introduction to TS-CHEM!<p> </p>
<h1 class="page_header" style="background-color: white; box-sizing: border-box; color: #347ab1; font-family: Lato, sans-serif; font-size: 24px; line-height: 1.2; margin-bottom: 0.5rem; margin-top: 0px;">
Introduction to TS-CHEM Features and Applications
</h1>
<div class="bodytext" style="background-color: white; box-sizing: border-box; color: #707070; font-family: Lato, sans-serif; font-size: 18px; margin: 50px 0px;">
TS-CHEM is a software studio for solute transport modeling within which the
user can:
</div>
<div class="bodytext" style="background-color: white; box-sizing: border-box; color: #707070; font-family: Lato, sans-serif; font-size: 18px; margin: 50px 0px;">
<ul>
<li>
Select from one of 32 widely used ADE models now assembled in a single
library
</li>
</ul>
<ul>
<li>
Specify a chemical for each Source Model (from the internal chemical
database or as a user-specified custom chemical)
</li>
</ul>
<ul>
<li>
Add one or more source models, at selected locations; commingled plumes
can be deconstructed to examine the contribution from each source
</li>
</ul>
<ul>
<li>
Analyze plume volume, mass and other attributes
</li>
</ul>
<ul>
<li>
Export plume data for plotting in other software
</li>
</ul>
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<div>For brief introductions to the main TS-CHEM features, view these <a href="https://transportstudio.com/videos.php" target="_blank">videos</a>.</div><div><br /></div><div>And check out these TS-CHEM <a href="https://transportstudio.com/example-applications.php" target="_blank">example applications</a>.</div>
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