Pesticide Contamination Prevention Act Review Process Triggered by Detections of Imidacloprid in Groundwater

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Legal Agricultural Use Determination

Detections of imidacloprid in groundwater were determined to be the result of legal agricultural use of a pesticide product or products containing imidacloprid. DPR responded by placing imidacloprid in the formal pesticide detection response process.

Formal Review Process

In September 2021, DPR began the formal review process of imidacloprid by notifying registrants with affected pesticide products.

September 2021 – Notice of Imidacloprid Product Residue Detections in California Groundwater and Registrant Opportunity to Request a Hearing, PDF

September 2021 – Notice of Hearing Request Received for the PCPA Review Process of Imidacloprid, PDF

October 2021 – Proposed Hearing Procedures for Certain Products Containing Imidacloprid, PDF

December 2021 – Final Hearing Procedures for Certain Products Containing Imidacloprid, PDF

January 2022 – Notice of Hearing Pertaining to Imidacloprid Product Residue Detections in Groundwater, PDF

March 2022 – Notice of Agenda for Phase 1 of Hearing Pertaining to Imidacloprid Product Residue Detections in Groundwater, PDF

April 2022 – Notice of Agenda for Phase 2(a) of Hearing Pertaining to Imidacloprid Product Residue Detections in Groundwater, PDF

May 2022 – Notice of Agenda for Phase 2(b) of Hearing Pertaining to Imidacloprid Product Residue Detections in Groundwater, PDF

PREC Subcommittee Findings and Recommendations

Director's Decision

Reports, Evidence, and Public Comments Received

Reports Received from State Agencies

Rebuttal Evidence Submitted by Hearing Participants

  • April 2022 – Evidence Requested by the Subcommittee for Phase 2 of the Hearing on Imidacloprid Detections in Groundwater, DPR, PDF
  • April 2022 – Excerpts from a Developmental Neurotoxicity Study of Imidacloprid Technical in Wistar Rats, submitted by UPL NA INC
  • April 2022 – J.J. Mauget’s Rebuttal to Supplemental Comments from the Natural Resources Defense Council, et al.
  • April 2022 – Imidacloprid: Perspective on Reported Groundwater Detections in California, Presented by Bayer during Phase 2(a)
  • April 2022 – Phase 2 Hearing for Imidacloprid Relevant to its Identification as a Groundwater Contaminant, Presented by OEHHA during Phase 2(a)
  • May 2022 – Bayer and Respondents’ Rebuttal Evidence as Outlined in California Department of Pesticide Regulation Notice 2022-09 regarding the Detections of Imidacloprid in California Groundwater
  • May 2022 – Evidence Requested by the Subcommittee for Phase 2 of the Hearing on Imidacloprid Detections in Groundwater, DPR, PDF

Evidence Submitted by Affected Registrants

Food and Agricultural Code section 13150(a) requires pesticide registrants subject to the Pesticide Contamination Prevention Act review process for imidacloprid to submit a report and evidence that demonstrates both of the following:

  1. That the presence in the soil of any active ingredient, other specified ingredient, or degradation product does not threaten to pollute the groundwater of the state in any region within the state in which the pesticide may be used according to the terms under which it is registered.
  2. That any active ingredient, other specified ingredient, or degradation product that has been found in groundwater has not polluted, and does not threaten to pollute, the groundwater of the state in any region within the state in which the pesticide may be used according to the terms under which it is registered.

DPR requested registrants to self-certify all reports and documents submitted to DPR are in compliance with Web Content Accessibility Guidelines (WCAG) 2.1, or a subsequent version, published by the Web Accessibility Initiative of the World Wide Web Consortium (W3C) at a minimum Level AA success criteria. Registrant reports self-certified as compliant can be found hyperlinked below. If a registrant did not self-certify their report, it will not be hyperlinked below, but you may request a copy of the submitted evidence by emailing PCPA@cdpr.ca.gov.

This table was last updated Friday, March 29, 2022.

Evidence Received from Registrants Subject to the PCPA Review Process
Evidence Received from Registrants Subject to the PCPA Review Process Date Received
Bayer Environmental Science/Bayer Environmental Science A Division of Bayer Cropscience LP and Bayer Cropscience LP (“Bayer”), PDF

Bayer’s submission is also on behalf of the following registrants:
  • Albaugh, LLC
  • Arborjet, Inc.
  • Arborsystems, Inc. (d/b/a/ ArborSystems)
  • Control Solutions, Inc.
  • Elanco US, Inc. (Bayer Healthcare/Elanco)
  • Ensystex IV, Inc.
  • Everiss NA, Inc. (a subregistrant of Albaugh)
  • FMC Corporation
  • Helena Agri-Enterprises, LLC
  • Innvictis Crop Care, LLC
  • Koppers Performance Chemicals, Inc.
  • Loveland Products Inc.
  • Makhteshim Agan of North America, Inc. (d/b/a ADAMA)
  • Nufarm Americas Inc.
  • OHP
  • Prime Source, LLC
  • Rainbow Treecare Scientific Advancements
  • Rockwell Labs Ltd d/b/a Maggie's Farms Ltd.
  • Rotam North America, Inc.
  • Sharda
  • SiteOne / Lesco, Inc.
  • Sulfur Mills
  • UPL NA Inc. (on behalf of UPL Delaware, Inc.)
  • Willowood, LLC, c/o Generic Crop Science, LLC
  • Winfield Solutions, LLC
February 18, 2022
Nufarm Americas Inc. AGT Division and Nufarm Americas, Inc. February 18, 2022
Scimetrics LTD. Corporation February 18, 2022
J.J. Mauget Co. February 18, 2022

Public Comments

Public comments and evidence submitted to DPR may have been edited for accessibility purposes. You may request a copy of any of the following public comments listed below by emailing PCPA@cdpr.ca.gov.

This table was last updated Monday, May 16, 2022.

Public comments
Date Received Commenter Name Commenter Affiliation
February 7, 2022 John Mora Garden and Turf Management, PDF
February 7, 2022 Laural Roaldson Laural Landscapes
February 8, 2022 Curtis Vaughan Seed Dynamics, Inc.
February 8, 2022 Wayne Pricolo Bowles Farming Company, PDF
February 10, 2022 Larry Cruff Not provided
February 11, 2022 Gary W. Van Sickle California Specialty Crops Council
February 15, 2022 Gary Atkins Not provided
February 15, 2022 Joshua Rahm California Walnut Commission, PDF
February 15, 2022 Jacob Villagomez California Citrus Mutual, PDF
February 16, 2022 Lisa Tate Rancho Filoso, LLC
February 16, 2022 Todd Birchler Nufarm Americas
February 16, 2022 Mary Zischke Grower-Shipper Association of Central California, PDF
February 17, 2022 Jeff Jensen Golf Course Superintendents Association of America, PDF
February 17, 2022 Ricardo Aguilar Aguilar Plant Care, PDF
February 17, 2022 Charles Brannon Sierra Gold Nurseries
February 17, 2022 Gregory C. Loarie Natural Resources Defense Council, Central California Environmental Justice Network, Pollinator Stewardship Council, Xerces Society for Invertebrate Conservation, Pesticide Action Network North America, and Center for Biological Diversity
February 18, 2022 James R. Cranney California Citrus Quality Council, PDF
February 18, 2022 Roger van Klaveren Generation Growers, Inc., PDF
February 18, 2022 Kim Wilenius C&M Nursery, PDF
February 18, 2022 Renee Pinel Western Plant Health
February 18, 2022 Adam Borchard California Fresh Fruit Association, PDF
February 18, 2022 Bill Freese Center for Food Safety
February 23, 2022 Steve Garsino Not provided
April 7, 2022 Jennifer Sass Natural Resources Defense Council, Central California Environmental Justice Network, Pollinator Stewardship Council, Xerces Society for Invertebrate Conservation, Pesticide Action Network North America, and Center for Biological Diversity
May 6, 2022 Alexis Temkin The Environmental Working Group

DPR also received approximately 3,869 public comments through an automated service called “EveryAction.” Of these 3,869 comments, approximately 289 were unique and contain differences in the subject line or body of the text itself. These “EveryAction” comments did not contain attachments.



For content questions, contact:
PCPA Hearing Coordinator
1001 I Street, P.O. Box 4015
Sacramento, CA 95812-4015
E-mail: PCPA@cdpr.ca.gov