The 1985 Pesticide Contamination Prevention Act (PCPA) (Assembly Bill 2021, Food and Agricultural Code [FAC] sections 13141 through 13152) requires the Department of Pesticide Regulation (DPR) to monitor and review the use of pesticides designated as having the potential to contaminate groundwater. If DPR detects a pesticide or its degradation product in groundwater, the PCPA requires DPR to determine if the detection(s) were the result of legal agricultural use. Once this determination is made, DPR notifies registrants of the detections and provides them with an opportunity to request a hearing. The purpose of the hearing is to review evidence to determine if continued use of the affected agricultural use pesticide products should be allowed. If DPR does not receive a hearing request from a registrant, DPR’s Director will cancel the registrant’s agricultural use product registration(s) containing imidacloprid.
DPR detected residues of imidacloprid in 15 groundwater wells at concentrations that exceeded the reporting limit of 0.05 parts per billion (ppb). Detected concentrations ranged from 0.051 to 5.97 ppb. Wells with detections above the reporting limit are located in Fresno, Santa Barbara, and Tulare counties. Based on its investigation, DPR determined the imidacloprid residues detected in groundwater were the result of legal agricultural use of a pesticide product or pesticide products containing imidacloprid.
On September 23, 2021, DPR notified all imidacloprid registrants of DPR’s groundwater detections and legal agricultural use determination, and provided registrants of agricultural use products with an opportunity to request a public hearing by October 25, 2021. Other impacted stakeholders were notified via California Notice 2021-08. On September 27, 2021, DPR received a hearing request from an imidacloprid registrant. Pursuant to FAC section 13150(b), DPR shall conduct a hearing within 180 days of this request. Any additional hearing requests will be accommodated at a single, combined hearing.
Within 60 days before this hearing, DPR will issue a separate California Notice to Stakeholders specifying the date, time, agenda, and location of the public hearing. More information regarding PCPA overall, and on DPR’s specific action for imidacloprid, can be found at <https://www.cdpr.ca.gov/docs/emon/grndwtr/imidacloprid.htm>.
Requests for additional information or questions should be directed to Ms. Kara James, Pesticide Registration Branch, at 916-324-3523 or by e-mail at <Kara.James@cdpr.ca.gov>.