Document ID: EPA-HQ-OPP-2003-0334-0004
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2007-09-20T04:00Z

<!DOCTYPE html
     PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
     "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<!-- EPA Template version 3.2.1, 28 June 2006 -->
<head>
	<!-- #BeginEditable "doctitle" -->
	<title>Minutes of the January 6, 2004 Exposure Modeling Public Meeting | Pesticides | US EPA</title>
	<meta name="DC.description" content="pesticide, pesticides,Access to and information regarding simulation models to predict pesticide concentrations in surface and ground water for use in both human health and aquatic ecological exposure assessments.  Exposure modeling public meeting products." />
	<meta name="keywords" content="EPA,Environmental Protection Agency, OPP, pesticides, pesticide, office of pesticide programs, scigrow, geneec, first, water models, exposure modeling public meeting" />
  <!-- #EndEditable -->
	<!-- #BeginEditable "metaElements" -->
	<meta name="DC.title" content="Minutes of the January 6, 2004 Exposure Modeling Public Meeting | Pesticides | US EPA" />
	<meta name="DC.subject" content="EPA,Environmental Protection Agency, OPP, pesticides, pesticide, office of pesticide programs, scigrow, geneec, first, water models, exposure modeling public meeting" />
	<meta name="DC.type" content="" />
	<!-- For date metadata, use the format YYYY-MM-DD -->
	<meta name="DC.date.modified" content="2007-06-11" />
	<meta name="DC.date.created" content="" />
	<meta name="DC.date.reviewed" content="" />
  <!-- #EndEditable -->

	<meta name="DC.language" content="en" />
	<meta name="DC.Creator" content="US EPA, Office of Pesticide Programs" />
	<meta http-equiv="Content-Style-Type" content="text/css" />
	<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
	<link rel="schema.DC" href="http://purl.org/dc/elements/1.1/" />
	<link rel="meta" href="http://www.epa.gov/labels.rdf" type="application/rdf+xml" title="ICRA labels" />
	
	<style type="text/css" media="screen">@import 'http://www.epa.gov/epafiles/s/epa.css';</style>
	<style type="text/css" media="screen">@import 'http://www.epa.gov/opp00001/styles/opp_styles.css';</style>
	<!--[if lt IE 7]>
	<link rel="stylesheet" type="text/css" href="http://www.epa.gov/epafiles/s/ie.css" />
	<link rel="stylesheet" type="text/css" href="http://www.epa.gov/opp00001/styles/opp_ie_styles.css" />
<![endif]-->
	<link rel="stylesheet" type="text/css" media="print" href="http://www.epa.gov/epafiles/s/print.css" />
	<script type="text/javascript" src="http://www.epa.gov/epafiles/js/epa-core.js"></script>
	<script type="text/javascript" src="http://www.epa.gov/epafiles/js/extra.js"></script>
</head> 

<body>
<p class="skip"><a id="skiptop" href="#content" title="Jump to main content.">Jump to main content.</a></p>

<div id="header"> <!-- START EPA HEADER -->

	<div id="logo"><a href="http://www.epa.gov/" title="US EPA home page"><img src="http://www.epa.gov/epafiles/images/logo_epaseal.gif" alt="[logo] US EPA" width="100" height="110" /></a></div>

	<div id="areaname"> <!-- START AREA NAME -->
		<p><span class="epaAreaName">Pesticides: Science and Policy </span></p>
  </div> <!-- END AREA NAME -->

	<!-- START SEARCH CONTROLS -->
	<form id="EPAsearch" method="get" action="http://nlquery.epa.gov/epasearch/epasearch">
		<!-- START AREA SPECIFIC LINKS AND SEARCH BOX  -->
		<!-- CHANGE links to point to your own recent additions and contact pages -->
		<!-- REMOVE recent additions link if your area doesn't have one -->
		<p><a href="http://cfpub.epa.gov/pesticides/recentadditions.cfm">Recent Additions</a> | <a href="http://www.epa.gov/pesticides/regulating/contacts.htm">Contact Us</a> 
			<span class="search"><strong>Search:</strong> 
			<input type="hidden" name="fld" value="gov/pesticides/science,oppfead1/trac/science,oppfead1/carat,oppfead1/cb/ppdc/,gov/scipoly/sap,oppad001,pesticides/antimicrobials,oppbppd1/biopesticides/regtools/guidelines,oppbead1/methods,oppbead1/labs,oppefed1/models,opptsfrs/home,gov/scipoly/oscpendo,gov/PR_Notices" />
			<input type="hidden" name="areaname" value="Pesticides: Science and Policy" />
			<input type="hidden" name="areacontacts" value="http://www.epa.gov/pesticides/science/contacts.htm" />
			<!-- AREA ADVANCED SEARCH URL HERE (OPTIONAL) -->
			<input type="hidden" name="areasearchurl" value="http://www.epa.gov/pesticides/search.htm" />
			<!-- THE REMAINING HIDDEN INPUTS ARE USED BY THE SEARCH ENGINE - DO NOT EDIT -->
			<input type="hidden" name="result_template" value="epafiles_default.xsl" />
 			<input type="hidden" name="filter" value="sample2filt.hts" />
			<input name="typeofsearch" id="EPAall" type="radio" value="epa"/><label for="EPAall">All EPA</label> 
			<input name="typeofsearch" id="Areaall" type="radio" value="area" checked="checked" /><label for="Areaall">This Area</label> 
			<input name="querytext" id="searchbox" value="" /> 
		  <input name="submit" id="searchbutton" type="submit" value="Go" /></span>
	  </p>
	</form> <!-- END SEARCH CONTROLS -->
		
	<ul> <!-- BEGIN BREADCRUMBS -->
		<li class="first">You are here: <a href="http://www.epa.gov/">EPA Home</a></li>
		<li><a href="http://www.epa.gov/pesticides/index.htm">Pesticides</a></li>		
		<!-- START AREA BREADCRUMBS -->
		<!-- #BeginEditable "breadcrumbs" -->		
		<li><a href="http://www.epa.gov/pesticides/science/index.htm">Science & Policy</a></li>
		<li><a href="http://www.epa.gov/pesticides/science/models_db.htm">Models 
            and Databases</a> </li>
		<li><a href="http://www.epa.gov/oppefed1/models/water/index.htm">Water Models		</a></li>
		<li><a href="http://www.epa.gov/oppefed1/models/water/emwg_top.htm">Exposure 		Modeling Public Meeting (EMPM) Information and Products</a></li>
		<li>Minutes of the January 6, 2004 Exposure Modeling Public Meeting</li>
    <!-- #EndEditable -->
		<!-- END AREA BREADCRUMBS -->
	</ul> <!-- END BREADCRUMBS -->

</div> <!-- END EPA HEADER -->

<hr class="skip" />

<p class="skip"><a id="pagecontents"></a><a id="pagetop"></a></p>
<div id="content"> <!-- BEGIN PAGE CONTENTS -->	<!-- EPA SITE-WIDE ANNOUNCEMENTS -->
	<!-- DO NOT REMOVE - this code is used for emergency messages -->
<!-- If this page is a Program Office or a Topics home page, CHANGE "sitewidec" TO "sitewideb" -->
	<p id="sitewidec"></p>

	<!-- BEGIN PAGE NAME -->
	<h1><!-- #BeginEditable "PageName" -->Minutes of the January 6, 2004 Exposure Modeling Public Meeting<!-- #EndEditable --></h1>
	<!-- END PAGE NAME -->

			<!-- BEGIN CONTENT AREA -->

			<!-- #BeginEditable "content" -->

<p>OPP Conference Room<br />
Crystal Mall Building 2<br />
Room 1126</p>

<p><strong>On this Page</strong></p>

<ul>
<li><a href="#attendees">Attendees</a></li>
<li><a href="#status">Status of Old Action Items</a></li>
<li><a href="#introduction">Introduction</a></li>
<li><a href="#brief">Brief Updates</a></li>
<li><a href="#next">Next Meeting</a></li>
<li><a href="#actions">Actions</a></li>
</ul>

<hr />

<h2 id="attendees">Attendees - needs checking:</h2>

<table class="table zebra" summary="Attendees">
<thead>
<tr><th scope="col">Name</th><th scope="col">Association</th></tr>
</thead>
<tbody>
<tr><td>Michael Barrett</td><td> 	OPP/EFED</td></tr>
<tr><td>Dirk Young</td><td> 	OPP/EFED</td></tr>
<tr><td>Betsy Behl </td><td>	OPP/EFED</td></tr>
<tr><td>William Eckel</td><td> 	OPP/EFED</td></tr>
<tr><td>Ron Parker</td><td> 	OPP/EFED</td></tr>
<tr><td>Mark Corbin</td><td>	OPP/EFED</td></tr>
<tr><td>Kevin Costello</td><td>	OPP/EFED</td></tr>
<tr><td>Marietta Exheverria</td><td>	OPP/EFED</td></tr>
<tr><td>Mohammed A. Ruhman</td><td>	OPP/EFED</td></tr>
<tr><td>Jim Lin</td><td>	OPP/EFED</td></tr>
<tr><td>Nelson Thurman</td><td> 	OPP/EFED</td></tr>
<tr><td>Joel Gagliardi</td><td>	OPP/BPPD</td></tr>
<tr><td>James Hetrick</td><td>			OPP/EFED</td></tr>
<tr><td>Subijoy Dutta</td><td>			OPP/EFED</td></tr>
<tr><td>Richard Lee</td><td>			OPP/EFED</td></tr>
<tr><td>Jim Wolf</td><td>			OPP/EFED</td></tr>
<tr><td>Fred Jenkins</td><td>			OPP/EFED</td></tr>
<tr><td>Alex Clem	</td><td>		OPP/EFED</td></tr>
<tr><td>R. David Jones</td><td>			OPP/EFED</td></tr>
<tr><td>Santhini Ramasamy</td><td>		OPP/HED</td></tr>
<tr><td>Cheryl Sutton</td><td>			OPP/EFED</td></tr>
<tr><td>Piyush Singh</td><td> 	DuPont</td></tr>
<tr><td>Mark Russell</td><td>	Dupont</td></tr>
<tr><td>Kathy Carr</td><td>	Monsanto</td></tr>
<tr><td>Mary Nett</td><td> 	WQC</td></tr>
<tr><td>Russell Jones</td><td> 	Bayer</td></tr>
<tr><td>Claude Beigel</td><td>	BASF</td></tr>
<tr><td>Geaorge Sabbagh</td><td>	Bayer</td></tr>
<tr><td>Paul Sweeney</td><td> 	Syngenta</td></tr>
<tr><td>Paul Hendley</td><td> 	Syngenta</td></tr>
<tr><td>Scott Jackson</td><td> 	BASF</td></tr>
<tr><td>Elise McCoy</td><td> 	FMC</td></tr>
<tr><td>Uwe Wanner</td><td> 	Crompton</td></tr>
<tr><td>Mark Cheplick</td><td> 	Waterborne Environmental</td></tr>
<tr><td>Marty Williams</td><td> 	Waterborne Environmental</td></tr>
<tr><td>Chris Harbourt</td><td>	Waterborne Environmental</td></tr>
<tr><td>Cathleen Hapeman</td><td>		USDA/ARS</td></tr>
<tr><td>Andy Newcombe</td><td>		Levine-Fricke-Recon</td></tr>
<tr><td>Tamara Estes</td><td>			Stone Environmental</td></tr>
<tr><td>Jim McFadden</td><td>			Rieerca</td></tr>
<tr><td>Ian Kennedy</td><td>			PMRA</td></tr>
<tr><td>David Sullivan</td><td>			Metam-Sodium Task Force</td></tr>
</tbody>
</table>

<p class="pagetop"><a href="#content">Top of page</a></p>
<hr />

<h2 id="status">Status of Old Action Items</h2>

<ul>
<li><p>Michael will schedule progress reports on the EFED research programs at the next EMWG meeting - <strong>delay till April</strong></p></li>
<li><p>EPA to put Gail's presentation (once rechecked by USGS) up on the website - <strong>not yet done</strong></p></li>
<li><p>EFED will ideally add Tier 2 GW needs and conceptual model to the agenda for the January meeting - <strong>Will be covered in April - see Betsy Behl comments</strong>.</p></li>
<li><p>Mark Cheplick to post details of code changes in PRZM on this and slides showing impact of changes on the list server. <strong>EXPRESS now available.  Wenlin Chen instigated code changes also now available</strong>.</p></li>
<li><p>Don will circulate an Excel spreadsheet of combined databases when available - aiming for the end of month  (Don will circulate an Excel spreadsheet of combined databases when available - aiming for the end of month  ) - <strong>PH to remind Don about this and the earlier action - Done</strong></p></li>
<li><p>Michael Barret still to circulate PGW database templates (last meeting) and, if appropriate, Michael will arrange for a discussion topic on this at the January EMWG - <strong>still under way</strong></p></li>
<li><p>Don Wauchope to post the proposal or the soil dissipation meeting at ACS anaheim (spring 2004) on the FIFRA-EMWG list server. <strong>Still to do</strong>.</p></li>
<li><p>Ron Parker to update FIFRA EMWG on progress of the FAO comparative model at the next meeting - <strong>delay till next meeting</strong>.</p></li>
<li><p>A demonstration of the EFED database will be given I possible at the January meeting - <strong>some budgetary issues, work still under way - may be given in April</strong>.</p></li>
<li><p>Michael Barrett to add a discussion of the details of the kinetics policy to the agenda of the first FIFRA EMWG after management has approved the draft as well as circulating the proposal itself. - <strong>awaiting approval</strong></p></li>
<li><p>Industry to present the findings of the FOCUS kinetics group at the same meeting - <strong>see later</strong></p></li>
<li><p>All speakers ideally to provide copies of their presentations to Michael Barrett - Michael to announce new file availability on web site by list server - <strong>Optional but nice to do</strong></p></li>
<li><p>EPA to consider adding a presentation on the work done internally on Foliar degradation, washoff and extraction factors as well as chemical application method factors for PRZM.  <strong>Industry may also develop presentations.  See later presentation</strong>.</p></li>
<li><p>EPA to review CARES and PLUS - add CARES as a standard topic for updates to future meetings - <strong>start at April meeting</strong>.</p></li>
</ul>

<p class="pagetop"><a href="#content">Top of page</a></p>
<hr />

<h2 id="introduction">Introduction</h2>

<p>Jim Lin introduced the meeting and held a minute of silence for Doug Urban who sadly passed away on December 26th, 2003.</p>

<p>As a reminder the FIFRA EMWG web site can be found at 
<a href="http://www.epa.gov/oppefed1/models/water/emwg_top.htm">http://www.epa.gov/oppefed1/models/water/emwg_top.htm</a></p>

<p class="pagetop"><a href="#content">Top of page</a></p>
<hr />

<h2 id="brief">Brief Updates</h2>

<p><strong>PRZM-EXAMS model/ EXPRESS</strong></p>

<p>EXPRESS Users manual still under development, internal review of EXPRESS will follow.  A finalized version of PRZM version 3.12 is due for approval - this will be completed when the projects budget is worked out.  3.12 Beta is still the "approved version".  Access to older versions of PRZM EXAMS will also be improved - All comments on version differences should be sent round via the list server.</p>

<p>Frequent teleconferences have been held between OPP and ORD on PRZM/EXAMS.  Recent topic was volatilisation.  David Jones reports that some inconsistencies have been found and the routines appear to be poorly validated.  </p>

<p>Industry has put the evaluation of EXPRESS on hold pending resolution of a bug found by Tamara Estes that seems to be due to some truncation issues.  If this is an issue also for EFED (this seems to be the case), it is important to resolve this soon.  <strong>Action</strong> for Mark Cheplick, Tammara Estes to ensure this is tracked down.</p>

<p><strong>PE4 - EFED Shell</strong></p>

<p>The shell has been refined and minor changes have been made.  Ian Kennedy reported the ability to set the application date relative to emergence date has been added.  It is clear that the PE4 Shell will remain the tool used by EPA exposure assessments for at least the next 4 or 5 months. </p>

<p>The 50+ scenarios are under review presently and EPA findings from the review of public/industry comments will be discussed by the EFED WQ tech team shortly.  <strong>Action</strong> - They will report back to the next EMWG meeting.</p>

<p><strong>Groundwater</strong></p>

<p>Betsy Behl reported that OPP, USGS (Jack Barbash et al) and others are working together to evaluate seven models, HYDRUS 2D, PRZM, LeachM , LeachP, RZWQM98, GLEAMS, BS2D being run with data from two PGW sites.  This group will report back on progress to EMWG next time.  Barbash has prepared a tool to try to make sure that "internal model settings" are comparable. </p> 

<p>PMRA are using LEACHM model presently and are developing scenarios for GW subsurface. A guidance document is being prepared.</p>

<p><strong>Regional Percent Crop area</strong></p>

<p>A policy refinement has been approved regarding the use of 0.87 default for minor crops.  These have been reviewed regionally (HUC2 - major basins - as this is judged suitable & conservative for water issues) to produce local max PCA values (e.g. CA uses 0.56).  This data was generated in the original evaluation of a national maximum.</p>

<p>The data should be made available soon (via Web site?)</p>

<p><strong>Scientist to Scientist Drinking Water treatment Workshop</strong></p>

<p>EPA OPP, OWOW, CLA, University Connecticut, NRDC, many others will attend meeting at end of January by invitation.  This is intended to be a brainstorming session and hence the numbers of attendees were kept low; all groups will need to take care to report the meeting findings back to their constituents to ensure the meeting findings are communicated most effectively.</p>

<p><strong>ACS Soil Dissipation Meeting ACS Anaheim 2004-01-06</strong></p>

<p>Don Wauchope and Al Barefoot are co-organizers for this symposium, which will focus on next steps following the workshop from 2002; there will be four talks from EPA and PMRA.  It is hoped that revised guidance on TFSD studies will be finalized later in 2004.</p>

<p><strong>FOCUS Kinetics Work Group Findings</strong></p>

<p>Russell Jones (BayerCropScience) and Claude Beigel (BASF) made two presentations.  Russell provided an overview of the concepts behind the FOCUS approaches while Claude examined the findings of the FOCUS subgroup on metabolite formation and decline.</p>

<p>Questions focused mainly on the details of some of the examples given by both speakers.  The topic of the formation fraction of metabolites generated considerable discussion.  The development of harmonized standard flow charts seems likely to reduce procedural debates and to standardise reporting and explication.  It was clear that "experts" are likely to apply expert judgement differently on some data sets - and there is still an element of artistry in the effective calculation of sensible kinetics data.</p>

<p>There may be a need for a standardised software package to reduce concerns about uniform encoding of the fitting models in standard mathematical software packages.  The background thinking might make a useful agenda topic at an upcoming EMWG meeting.</p>

<p><strong>Foliar Degradation Data Derivation from Magnitude of Residue Studies - David Jones (and Santhini Ramasamy)</strong></p>

<p>David Jones described a project stimulated by both internal EFED actions and also some data developed on Carbaryl by the registrant.  They did not consider at foliar dislodgeable studies aimed at human exposure.   He made the point that EPA may relax their thinking on using "foreign data" in future where the climate conditions are appropriate to US uses.  David made the point that the presentation actually measures dissipation rather than degradation; and therefore, at some point, it is possible that weather data availability might be added as another data acceptability requirement for a residue dataset.</p>

<p>This approach offers the potential for replacing the aerobic soil default value for foliar degradation.  Can be a very significant term for reducing aquatic exposure assessments - particularly for foliar applied compounds.  The obvious conclusion is that it seems as if the inclusion of a few extra sampling points in a Magnitude of Residue field program is a cheap way of obtaining useful data for some products.</p>

<p><strong>Spatial approaches for designing a statistically-based ecological monitoring program: Lessons learned - Nelson Thurman and Paul Hendley</strong></p>

<p>Joint presentations were made to discuss learning points noted from the work conducted to identify sites for the atrazine ecological monitoring study required by the Jan 31, 2003 IRED.</p>

<p>Questions were asked about the size of selected streams and the planned extent of the monitoring of atrazine use near the selected sampling sites.</p>

<p><em>Note</em>:  Due to the size of the powerpoint presentation files, anyone interests in getting a copy should contact the presenters.</p>

<p><strong>A degree day concept for estimating degradation time under Field Conditions - Scott Jackson</strong></p>

<p>Measurement of accumulated heat is known as physiological time.  The underlying concept is that since the heat unit approach works well for insects and crops, it therefore should work for the soil organisms that degrade agricultural chemicals.  Due to non-availability of max and min soil and air temperatures (average may be all that is available in some regions), the authors had to generate models based on mean temperature values.  They also added an empirical volumetric water content correction t improve water content depletion.</p>

<p>A question was asked about whether the day length was critical - Answer - No.  But unless photosynthesis provides enough energy (and this is dependent on day length), the system may fail.</p>

<p>The publication described in Scott's presentation is available in full in Pesticide Management Science, Vol. 59, 10 Oct 2003.</p>

<p class="pagetop"><a href="#content">Top of page</a></p>
<hr />

<h2 id="next">Next Meeting</h2>

<p>Next meeting has been scheduled for April 6.</p>

<p class="pagetop"><a href="#content">Top of page</a></p>
<hr />

<h2 id="actions">ACTIONS</h2>

<ol>

<li><p>Larry Burns to provide a summary of recent changes and version numbers and the system to access older versions.</p></li>
<li><p>There will be a presentation on GW model evaluation program at the next EMWG meeting.</p></li>
<li><p>EXPRESS Coding issue to be resolved if possible so that the industry review of EXPRESS can be completed.</p></li>
<li><p>EFED review of PRZM-EXAMS scenarios to be discussed.</p></li>
<li><p>EFED to provide information on new PCA policy for minor crops as soon as feasible.</p></li>
<li><p>Mark Cheplick, Tammara Estes and Ron Parker to resolve issue of reported truncation bug in EXPRESS and report via list server.</p></li>
</ol>

<p class="pagetop"><a href="#content">Top of page</a></p>
<hr />

      <!-- #EndEditable --> 

</div> <!-- END CONTENT -->

<hr class="skip" />

<div id="area-nav"> <!-- BEGIN LEFT SIDEBAR NAVIGATION -->
	<h3 class="skip">Local Navigation</h3>
	<ul>
		<li><a href="http://www.epa.gov/pesticides/">Pesticides Home</a><hr /></li>
		<li><a href="http://www.epa.gov/pesticides/science/index.htm">Science & Policy Home</a></li>
		<li><a href="http://www.epa.gov/pesticides/science/committees.htm">Advisory Committees</a></li>
		<li><a href="http://www.epa.gov/pesticides/science/policies.htm">Policy & Guidance</a></li>
		<li><a href="http://www.epa.gov/pesticides/science/guidelines.htm">Test Guidelines</a></li>
		<li><a href="http://www.epa.gov/pesticides/science/models_db.htm">Models & Databases</a></li>
		<li><a href="http://www.epa.gov/oppbead1/labs/index.htm">Laboratories</a></li>
		<li><a href="http://www.epa.gov/oppbead1/methods/index.htm">Analytical Methods Procedures</a></li>
	</ul>
</div> <!-- END LEFT SIDEBAR NAVIGATION -->

<hr class="skip" />

<div id="footer"> <!-- BEGIN FOOTER -->
	<ul id="globalfooter">
		<li><a href="http://www.epa.gov/">EPA Home</a></li>
		<li><a href="http://www.epa.gov/epafiles/usenotice.htm">Privacy and Security Notice</a></li> 
		<!-- BEGIN AREA COMMENTS LINK -->
		<!-- CHANGE link to point to your own contact page -->
		<li class="last"><a href="http://www.epa.gov/pesticides/science/contacts.htm">Contact Us</a></li>
		<!-- END AREA COMMENTS LINK -->
	</ul>

</div> <!-- END FOOTER -->

<p class="skip"><a id="skipbot" href="#content" title="Jump to main content.">Jump to main content.</a></p>
</body>
</html>