Comment submitted by Mark H. Wills, P.E., Riverside County Flood Control & Water Conservation District

The District is submitting the attached letter on behalf of the Riverside County MS4 Permittees to reiterate and expand upon testimony provided during the January 22, 2010 Regional Stakeholder Meeting in Oakland, California. The District’s testimony highlighted the significant impacts that the lack of harmonization between the Clean Water Act and the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) has on local governments subject to Clean Water Act permitting requirements. The current lack of consideration of potential water column and sediment toxicity for products regulated and legally used under FIFRA has resulted in measurable toxicological impacts on local receiving waters and resulted in legal and economic liabilities for Riverside County NPDES MS4 Permittees under the Clean Water Act. This letter provides a summary analysis of our data regarding pyrethroid pesticide toxicity, presents the legal and economic liabilities incurred by our Permittees due to legal pyrethroid pesticide use, and references the CD-ROM containing the data and reports provided to USEPA representatives at the public meeting.