UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

 WASHINGTON, DC 20460

OFFICE OF CHEMICAL SAFETY 

AND POLLUTION PREVENTION

MEMORANDUM

Date: April 26, 2016

Subject: Supplementary Guidance for Phase IV of Crop Group Revisions Rulemaking

From: Susan Lewis, Director 

Registration Division

To: All RD Staff

The fourth rulemaking to revise the crop groups in 40 CFR §180.41 establishes: Leafy Vegetable 

Crop Group 4-16; Brassica Head and Stem Vegetable Crop Group 5-16; Stalk, Stem, and Leaf 

Petiole Vegetable Crop Group 22; Tropical and Subtropical Fruit, Edible Peel, Crop Group 23; and 

Tropical and Subtropical Fruit, Inedible Peel, Crop Group 24. Implementation of these new crop 

groups will require more planning and effort because of the re-structuring of crop subgroups and 

several instances where commodities will have different representatives. The attached guidance from 

HED’s ChemSAC provides an overview of changes and clarifies the implementation strategies

associated with these new crop groups1

. 

In addition to the ChemSAC memorandum, RD Management would like to highlight the following

points regarding implementation of these new crop groups:

• As with the previous phases of this project, when an existing crop group is amended in a 

manner that expands or contracts its coverage of commodities, EPA will retain the preexisting crop group in §180.41; insert the revised crop group immediately after the preexisting crop group in §180.41; and title the revised crop group in a way that clearly 

differentiates it from the pre-existing crop group. EPA will initially retain pre-existing crop 

groups that have been superseded by revised crop groups. EPA will not establish new 

tolerances under the pre-existing groups. However, all existing tolerances will remain until 

the EPA has assessed any potential risks due to the additional exposures of the new crops

added to the groups and established the appropriate tolerances. EPA plans to eventually 

convert tolerances for any pre-existing crop group to tolerances with coverage under the 

revised crop group. This conversion will occur through the registration review process and in 

the course of evaluating new uses for a pesticide registration when the EPA is petitioned to 

 1 11/04/2015 Memorandum from ChemSAC to Vogel, Dana and Rowland, Jess; “Implementation Guidance for 

Phase IV of Crop Group Revisions Rulemaking”
Page 2 of 3

update the crop groups. EPA has encouraged petitioners for tolerances to address crop group 

conversions in their requests. A PRIA category, R175, was created to address these 

conversions.

• Crop group conversions based upon Crop Group 4 and 5 tolerances will not be straightforward 

and may result in displaced individual commodities. For example, arugula, garden cress, and

upland cress were members of Subgroup 4A (represented by lettuces and spinach) that will 

become members of Subgroup 4-16B (represented by mustard greens), and a conversion request 

to Crop Subgroup 4-16A would result in the displacement of those 3 commodities. Therefore, for 

Crop Groups 4 and 5 conversion requests, the EPA will accept the R175 PRIA fee request for the 

crop group conversion and the establishment of tolerances for those individual displaced 

commodities. The attached Crop Group Conversion Plan for Existing Tolerances as a Result of 

Creation of New Crop Groups under Phase IV (4-16, 5-16, and 22) provides guidance the Product 

Management Teams and registrants can follow for all the existing tolerances involving 

Groups/Subgroups 4 and 5 currently listed in the 40 CFR23

. The attachment outlines a path forward 

for registrants to request a crop group conversion as well as tolerances for displaced commodities 

without incurring additional fees for any of those individuals, thereby ensuring that tools 

previously in place for minor use growers are not lost in the conversion process.

• The Groups 4 and 5 conversion plan attachment also allows the establishment of a tolerance for 

Stalk and Stem Vegetable Subgroup 22A for specific cases where a tolerance was previously 

established on asparagus and individual tolerances would otherwise be established on one or 

more displaced commodities that will be members of the subgroup (kohlrabi, celtuce or Florence 

fennel). In these specific cases, the EPA will convert the individual tolerance for asparagus to 

Stalk and Stem Vegetable Subgroup 22A, instead of establishing individual tolerances for 

kohlrabi, celtuce or Florence fennel. Asparagus is the representative commodity for Subgroup 

22A, and establishing the subgroup tolerance rather than maintaining individual tolerances on the 

representative commodity and establishing additional individual, displaced tolerances will avoid 

confusion and allow for streamlining of processes.

• The proposed tolerance levels discussed in the Groups 4 and 5 conversion plan attachment are 

based upon the existing tolerances in 40 CFR §180. EPA will consider revising these tolerances 

in order to align with international tolerances. 

• Historically, HED has recommended individual tolerances for several tropical and subtropical 

commodities based upon commodity definitions and residue data extrapolations contained in a 

Reviewer’s Guide4

. RD will no longer establish tolerances based upon these extrapolations or 

 2 11/03/2015. “Crop Group Conversion Plan for Existing Tolerances as a Result of Creation of New Crop 

Groups under Phase IV (4-16, 5-16, and 22).”

3 4/12/2016. “Addendum. Crop Group Conversion Plan for Existing Tolerances as a Result of Creation of 

New Crop Groups under Phase IV (4-16, 5-16, and 22).”

4 06/14/2006. Memorandum from Schneider, Bernard to Madden, Barbara. “Reviewer’s Guide and 

Summary of HED ChemSAC Approvals for Amending Crop Group/Subgroups [40 CFR 180.41] and 

Commodity Definitions [40 CFR 180.1(h)].”
Page 3 of 3

commodity definitions. Moving forward, tropical and subtropical fruit tolerances will be

established based upon the representative commodities for Crop Groups 23 and 24.

• Although EPA will no longer recommend or establish individual tropical and subtropical fruit 

commodity tolerances based on the Reviewer’s Guide, the Agency does not believe that the 

tolerances established based on the Guide underestimate potential residues. Therefore, those

individual tolerances based on the Reviewer’s Guide will not be retroactively altered or removed. 

A list of these tolerances, by active ingredient, is provided in an attachment5 in order to provide 

reviewers with additional information.

• Watercress will become a member of Crop Group 4-16, in Subgroup 4-16B. The EPA has 

reviewed the requirement of a chemical-specific watercress aquatic dissipation study, as outlined 

40 CFR §180.158.1300- Environmental Fate. Because of the limited acreage of watercress grown 

in the U.S., EPA has determined that it will waive the requirement of a chemical-specific aquatic 

dissipation study specifically for watercress.6 EPA may conduct conservative screening-level 

assessments and model application scenarios to water such as the Tier I Rice Model (or Modified 

Cranberry Model), or the Tier II Pesticides in Flooded Application Model (PFAM) to estimate 

exposures to drinking water and ecological receptors based on applications to watercress.

• When registrants petition for use on Crop Group 4-16 or Subgroup 4-16B, including watercress,

they should list specific crop use directions on the proposed product label for watercress. Though 

watercress will be listed with the entire group/subgroup and the general use directions will be the 

same as all other crops within the group or subgroup, the label directions must clearly state that

growers should not be making applications directly to water, e.g. “For applications made to 

watercress, production fields must be drained of water at least 24 hours prior to application 

and water must not be reapplied to the field for a minimum of 24 hours following the 

application”. If the label does not specify that applications are not to be made with field while 

water is present, then the Agency will assess watercress as direct applications to water.

A detailed account of the changes for the Phase IV rulemaking will be available at 

www.regulations.gov in docket: EPA-HQ-OPP-2006-0766. If you have any questions or concerns 

regarding the implementation of the fourth phase of crop group revisions, please contact Barbara 

Madden, madden.barbara@epa.gov. 

 5 11/03/2015. “Crop Group Conversion Plan for Existing Tolerances as a Result of Creation of New Crop 

Groups under Phase IV (Groups 23, 24).”

6 12/02/15. “Recommendation for a General Waiver for the Aquatic Field Dissipation Study Requirement 

for Proposed Watercress Uses”