Analysis of Subsurface Metabolism in Groundwater Modeling in Support of Human Health Drinking Water Assessments for Pesticides

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Center for Biological Diversity filed 1 comment on this docket between Jun 7, 2021 and Jun 7, 2021. 1 other organizations filed here. The comment window closed 1848d ago.

What Center for Biological Diversity filed (1)

Abstract

The Environmental Fate and Effects Division (EFED) provides estimates of potential exposure to pesticides in drinking water to the Health Effects Division (HED) for use in human dietary risk assessments. The Pesticide Root Zone Model Groundwater (PRZM-GW), now implemented in the Pesticide in Water Calculator, was developed as a regulatory model to estimate pesticide concentrations in vulnerable groundwater sources. The groundwater conceptual model assumed the aerobic soil metabolism (ASM) rate declined linearly to zero at 1-meter, based on precedent of use in other GW models in use at the time. Hydrolysis is assumed to occur throughout the soil profile. To explore this further, EFED scientists, in collaboration with the Office of Research and Development (ORD), first completed a literature search of available information related to subsurface degradation and then explored potential revisions to the conceptual GW model underlying PWC. This docket contains project documents and a request for public comments on the summary of analyses

• Center for Biological DiversityTHIS ORG

  1 filing · confidence 97%
• Minor Crop Farmer Alliancetrade assoc.

  1 filing · confidence 85%