Public Notice of Draft National Pollutant Discharge Elimination System NPDES Pesticide General Permit PGP for Point Source Discharges to Waters of the United States from the Application of Pesticides Fact Sheet A

United States Environmental Protection Agency
Public Notice of:

Draft National Pollutant Discharge Elimination System (NPDES)
Pesticide General Permit (PGP) for Point Source Discharges to Waters
of the United States from the Application of Pesticides

Fact Sheet

A NOTE TO REVIEWERS AND COMMENTERS:

EPA proposes the text in this draft Fact Sheet as part of the Proposed 2021 PGP. Where the Fact
Sheet reflects permit provisions that are unchanged from the 2016 PGP, EPA proposes the draft
Fact Sheet text in present tense rather than conditional tense (e.g., "This Part requires" versus "This
Part would require", or "The Operator must" versus "The Operator would be required to"). Where
EPA proposes specific changes to the permit from the 2016 PGP, the Fact Sheet text reflects that
(e.g., "EPA proposes that..."). With the inclusion of this note, reviewers and commenters should
read and interpret all text as proposed and not final. EPA is proposing the Fact Sheet in this format
so readers can see any proposed language as it might be written in the final permit and to improve
editing efficiency during the permit finalization process.

Agency: United States Environmental Protection Agency
Action: Notice of Draft NPDES General Permit

PRE-PUBLICATION NOTICE. All 10 U.S. Environmental Protection Agency Regions signed the following
document on December 14, 2020, and EPA is submitting it for publication in the Federal Register (FR). This
document is not disseminated for purposes of EPA's Information Quality Guidelines and does not represent an
Agency determination or policy. While we have taken steps to ensure the accuracy of this Internet version of the
document, it is not the official version. Please refer to the official version in a forthcoming FR publication, which
will appear on the Government Printing Office's govinfo website fhttps://www.govinfo.gov/app/colkction/fr). It will
also appear on Regulations.gov fhttps://www. regulations, gov) in Docket No. EPA-HQ-OW-2020-0005. Once the
official version of this document is published in the FR, this version will be removed from the internet and replaced
with a link to the official version.

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U.S. Environmental Protection Agency	Draft 2021 NPDES Pesticide General Permit Fact Sheet

Note: This document is aprepublication version, signed by all 10 U.S. EPA Regions on December 14, 2020. EPA is
submitting it for publication in the Federal Register. We have taken steps to ensure the accuracy of this version, but
it is not the official version.

CONTENTS

I.	Background	3

1.	Clean Water Act	3

2.	NPDES Permits	3

3.	History of Pesticide Application Regulation	4

4.	Court Decisions Leading to the CWA Regulation Concerning Pesticide
Applications	5

II.	Structure of the Draft 2021 PGP	6

1.	General	6

2.	Conformance to Court Decisions	7

3.	Sharing of Responsibilities	10

III.	Summary of Draft 2021 PGP Conditions	11

1.	Coverage Under the Draft 2021 PGP	11

1.1	Eligibility	11

1.2	Authorization to Discharge Pollutants Under this Permit	20

1.3	Alternative Permits	33

1.4	Severability	35

1.5	Other Federal and State Laws	35

1.6	Federally Listed Endangered and Threatened Species and Designated Critical
Habitat	35

2.	Effluent Limitations	35

2.1	Applicators' Responsibilities	45

2.2	Decision-makers' Responsibilities	46

3.	Water Quality-Based Effluent Limitations	75

4.	Site Monitoring	90

4.1	Visual Monitoring Requirements for Pesticide Applicators	92

4.2	Visual Monitoring Requirements for all Operators	93

5.	Pesticide Discharge Management Plan (PDMP)	93

5.1	Contents of the PDMP	94

5.2	Pesticide Discharge Management Plan Modifications	97

5.3	Pesticide Discharge Management Plan Availability	98

6.	C orrective Acti on	98

6.1	Situations Requiring Revision of Pest Management Measures	98

6.2	Corrective Action Deadlines	99

6.3	Effect of Corrective Action	99

6.4	Adverse Incident Documentation and Reporting	100

6.5	Reportable Spills and Leaks	102

6.6	Documentation for Other Corrective Action	103

7.	Recordkeeping and Annual Reporting	103

7.1 Records to be Kept by all Operators (all Decision-makers and all Applicators)	104

li

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

Note: This document is aprepublication version, signed by all 10 U.S. EPA Regions on December 14, 2020. EPA is
submitting it for publication in the Federal Register. We have taken steps to ensure the accuracy of this version, but
it is not the official version.

7.2 Records to be Kept by all For-Hire Applicators 104

7.3 Records to be Kept by Small Entities, Submitting an NOI 104

7.4 Records to be Kept by Large Entities, Submitting an NOI 105

7.5 Retention of Records 106

7.6 Annual Reports 106

7.7 Annual Reporting for Any Decision-maker with Discharges of Pollutants to
Waters of the United States Containing NMFS Listed Resources of Concern, as
Defined in Appendix A of the Permit, and Who is a Small Entity 108

7.8 Electronic Reporting Requirement 109

8. EPA Contact and Mailing Addresses 109

9. Permit Conditions Applicable to Specific States, Indian Country, or Territories 109

10. Permit Appendices 110

A. Definitions and Acronyms 110

B. Standard Permit Conditions 110

C. Areas Covered 110

D. Notice of Intent Form 111

E. Notice of Termination Form Ill

F. Pesticide Discharge Evaluation Worksheet Ill

G. Annual Report Template Ill

H. Adverse Incident Report Template 112

I. Endangered Species Procedures 112

IV. Fact Sheet Appendices 114

APPENDIX A. List of pesticides and degradates which exceeded aquatic-life

benchmarks in the USGS 2014 study and the CA Central Valley Regional 303(d)

impairment list of pesticides 114

APPENDIX B. Chemicals and Exceedances in USGS 2014 Study and Subsequent

Mitigation Measures that Reduce Pesticides Residues in Waters 118

APPENDIX C. Summary of Pesticide-Specific Exceedance Data and Risk Mitigation

Actions 119

APPENDIX D. Cost Impacts and Number of Entities Covered 121

L Background

The United States Environmental Protection Agency (EPA) is proposing to reissue the
National Pollutant Discharge Elimination System (NPDES) pesticide general permit (draft 2021
PGP) which authorizes the point source discharges of biological pesticides, and chemical
pesticides that leave a residue, to waters of the United States. Once finalized, the latest version of
the draft 2021 PGP will replace EPA's 2016 PGP, which expires on October 31, 2021. This fact
sheet describes the draft 2021 PGP which is being proposed. Once finalized, the draft 2021 PGP
will be available to Operators in geographic areas where EPA is the NPDES permitting
authority. Appendix C of the draft 2021 PGP contains a list of areas eligible for coverage.

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

Conditions and requirements in the draft 2021 PGP remain largely unchanged from the
2011 PGP and 2016 PGP. Implementation of the 2011 PGP and 2016 PGP has been successful.
The regulated community has raised very few implementation issues, which have been
successfully resolved. The provisions in the draft 2021 PGP for pesticide applications during
emergencies have been effectively implemented. EPA is not aware of any lawsuits brought
against Operators discharging pollutants under EPA's 2016 PGP. However, in an effort to pursue
continuous improvement to protect water quality and pursuant to the requirements in 40 CFR
124.10, EPA seeks comment on the draft 2021 PGP. Supporting information and materials for
the draft 2021 PGP, are included in Docket ID No. EPA-HQ-OW-2020-0005 available at
https://www.regulations.gov/.

The draft 2021 PGP includes some minor changes from the 2016 PGP which are discussed
below:

Notices of Intent (NOIs)

Under the 2016 PGP, Decision-makers who were required to submit NOIs were
automatically covered under the permit until January 12, 2017. Additional time was provided to
allow new Decision-makers enough time to read and understand the permit requirements and
comply with the recordkeeping and reporting requirements of the permit and to provide a
transition period for existing Decision-makers under the 2011 PGP to resubmit NOIs under the
2016 PGP. For the 2021 permit, EPA is planning to finalize and issue with sufficient time to give
Decision-makers time to prepare for filing a notice of intent to be covered under the new permit
prior to the October 31, 2021 effective date. Under the draft 2021 PGP, on the effective date of
the permit, Decision-makers who are required to submit an NOI are required to submit ten or
thirty (for activities in the NMFS Listed Resources of Concern) days prior to discharging
pollutants to a water of the United States. Other Operators who are not required to submit NOIs
continue to be automatically covered.

NPDES eReporting Tool (NeT)

Under the 2016 PGP, Notices of Intent (NOIs), Notices of Termination (NOTs), and
annual reports must be prepared and submitted using EPA's eNOI System unless the Decision-
maker has obtained a waiver from electronic reporting requirements. See Part 7.8 of the draft
2021 PGP for detailed electronic reporting requirements. EPA has moved or will move all
electronic reporting for the NPDES program to the NPDES eReporting Tool (NeT). Under the
draft 2021 PGP, Decision-makers must prepare and submit their NOIs, NOTs, and annual reports
using EPA's NPDES eReporting Tool (NeT) unless the Decision-maker has obtained a waiver
from electronic reporting requirements. Conditions to obtain a waiver from electronic reporting
requirements under the draft 2021 PGP are: 1) if the Decision-maker is physically located in a
geographic area {i.e., zip code or census tract) that is identified as under-served for broadband
Internet access in the most recent report from the Federal Communications Commission; or 2) if
the Decision-maker has limitations regarding available computer access or computer capability.

Appendix A, Definitions, Abbreviations, and Acronyms

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

EPA has added in Appendix A of the draft 2021 PGP the definitions for the term "Pesticide
discharges to waters of the United Stated from pesticide application" and updated "pesticide
residue." These terms are identical to those in 40 CFR 122.2.

Appendix B, Standard Permit Conditions

To ensure consistency with 40 CFR 122.41, the standard permit conditions are included in
the permit.

Appendix C, Areas Covered

The draft 2021 PGP is available in those areas where EPA is the NPDES permitting
authority; these areas include Indian Country where there is no EPA-approved permitting
program, federal facilities, and states that have not been approved to administer the NPDES
program. The complete list of areas of geographic coverage of this permit, along with the
NPDES permit numbers, are listed in Appendix C of the draft 2021 PGP. Subsequent to issuance
of the 2016 PGP, the State of Idaho received authorization to administer the entire NPDES
program; therefore, pesticide applications in Idaho (where Idaho has permitting authority) will be
covered under the state's NPDES program. In addition, since 2016, several tribes were newly
recognized by the federal government, which means that pesticide applications on those tribal
lands may need coverage under the draft 2021 PGP or an individual permit. These changes are
reflected in Appendix C of the draft 2021 PGP.

1. Clean Water Act

Section 301(a) of the Clean Water Act (CWA) provides that "the discharge of any pollutant
by any person shall be unlawful" unless the discharge is in compliance with certain other
sections of the Act. 33 U.S.C. 1311(a). The CWA defines "discharge of a pollutant" as "(A) any
addition of any pollutant to navigable waters from any point source, (B) any addition of any
pollutant to the waters of the contiguous zone or the ocean from any point source other than a
vessel or other floating craft." 33 U.S.C. 1362(12). A "point source" is any "discernible,
confined and discrete conveyance" but does not include "agricultural stormwater discharges and
return flows from irrigated agriculture." 33 U.S.C. 1362(14).

The term "pollutant" includes, among other things, "garbage... chemical wastes, biological
materials .. .and industrial, municipal, and agricultural waste discharged into water." 33 U.S.C.
1362(6).

One way a person may discharge a pollutant without violating the section 301 prohibition
is by obtaining authorization to discharge (referred to herein as "coverage") under a section 402
NPDES permit (33 U.S.C. 1342). Under section 402(a)(1), EPA may "issue a permit for the
discharge of any pollutant, or combination of pollutants, notwithstanding section 1311(a)" upon
certain conditions required by the Act.

2. NPDES Permits

An NPDES permit authorizes the discharge of a pollutant or pollutants into a receiving
water under certain conditions. The NPDES program relies on two types of permits: individual

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

and general. An individual permit is a permit specifically tailored for an individual discharger or
situations that require individual consideration. Upon receiving the appropriate permit
application(s), the permitting authority, e.g., EPA or a state, develops a draft permit for public
comment for that particular discharger based on the information contained in the permit
application (type of activity, nature of discharge, receiving water quality). Following
consideration of public comments, a final permit is then issued to the discharger for a specific
time period (not to exceed 5 years) with a provision for reapplying for further permit coverage
prior to the expiration date.

In contrast, a general permit covers multiple facilities/sites/activities within a specific
category for a specific period of time (not to exceed 5 years). For general permits, the permitting
authority, e.g., EPA, or a state, develops and issues the permit in advance, with dischargers then
generally obtaining coverage under the permit through submission of a Notice of Intent (NOI). A
general permit is also subject to public comment prior to issuance. EPA is the permitting
authority for the geographic areas that have not been authorized by EPA to issue NPDES
permits. Each permitting authority should review their permittees and geographic area and
develop appropriate permits considering technology and water quality. In addition, states may
issue a permit that has different requirements from EPA's permit for similar types of discharges
of pollutants, as long as it satisfies the regulatory requirements of the NPDES program, the
CWA, and state law.

Under 40 CFR 122.28, general permits may be written to cover categories of point sources
having common elements, such as facilities that involve the same or substantially similar types
of operations, that discharge the same types of wastes, or that are more appropriately regulated
by a general permit. Given the significant number of pesticide operations requiring NPDES
permit coverage and the discharges of pollutants common to these operations, it makes
administrative sense to issue the general permit, rather than issuing individual permits to each
Operator. Courts have approved of the use of general permits. See e.g., Natural Res. Def.

Council v. Costle, 568 F.2d 1369 (D.C. Cir. 1977); EDC v. US EPA, 344 F.3d 832, 853 (9th Cir.
2003). The general permit approach allows EPA to allocate resources in a more efficient manner
and to provide more timely coverage and may significantly simplify the permitting process for
the majority of pesticide dischargers. As with any permit, the CWA requires the general permit
to contain technology-based effluent limitations, as well as any more stringent limits when
necessary to meet applicable state water quality standards. State water quality standards apply in
the state and in the territorial seas, defined in section 502(8) of the CWA as extending three
miles from the baseline. Pacific Legal Foundation v. Costle, 586 F.2d 650, 655-656 (9th Cir.
1978); Natural Resources Defense Council, Inc. v. U.S. EPA, 863 F.2d 1420, 1435 (9th Cir.

1988).

3. History of Pesticide Application Regulation

EPA regulates the sale, distribution and use of pesticides in the United States under the
statutory framework of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) to
ensure that when used in conformance with FIFRA labeling directions, pesticides will not pose
unreasonable risks to human health and the environment. All new pesticides, for which
registration is required, must undergo a registration procedure under FIFRA during which EPA

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

assesses a variety of potential human health and environmental effects associated with use of the
product. Under FIFRA, EPA is required to consider the effects of pesticides on the environment
by determining, among other things, whether a pesticide "will perform its intended function
without unreasonable adverse effects on the environment," and whether "when used in
accordance with widespread and commonly recognized practice [the pesticide] will not generally
cause unreasonable adverse effects on the environment." 7 U.S.C. 136a(c)(5). In performing this
analysis, EPA examines the ingredients of a pesticide, the intended type of application site and
directions for use, and supporting scientific studies for human health and environmental effects
and exposures. The applicant for registration of the pesticide must provide specific data from
tests done according to EPA guidelines.

When EPA approves a pesticide for a particular use, the Agency imposes restrictions
through labeling requirements governing such use. The restrictions are intended to ensure that
the pesticide serves an intended purpose and avoids unreasonable adverse effects. It is illegal
under section 12(a)(2)(G) of FIFRA to use a registered pesticide in a manner inconsistent with its
labeling. States have primary authority under FIFRA to enforce "use" violations, but both the
states and EPA have ample authority to prosecute pesticide misuse when it occurs. 7 U.S.C.
13 6j (a)(2)(G).

4. Court Decisions Leading to the CWA Regulation Concerning Pesticide Applications

In the past, several courts have addressed the question of whether the CWA requires
NPDES permits for pesticide applications. These cases resulted in some confusion among the
regulated community and other affected citizens about the applicability of the CWA to pesticides
applied to waters of the United States.

On November 27, 2006, EPA issued a final rule (hereinafter called the "2006 NPDES
Pesticides Rule") clarifying two specific circumstances in which an NPDES permit was not
required to apply pesticides to or around water. They were: 1) the application of pesticides
directly to water to control pests; and 2) the application of pesticides to control pests that are
present over, including near, water where a portion of the pesticides will unavoidably be
deposited to the water to target the pests, provided that the application is consistent with relevant
FIFRA requirements in both instances. The rule became effective on January 26, 2007.

On January 7, 2009, the Sixth Circuit vacated EPA's 2006 NPDES Pesticides Rule under a
plain language reading of the CWA. National Cotton Council of America v. EPA, 553 F.3d 927
(6th Cir., 2009). The Court held that the CWA unambiguously includes "biological pesticides"
and "chemical pesticides" with residuals within its definition of "pollutant." Specifically, an
application of chemical pesticides that leaves no excess portion is not a discharge of a pollutant,
and the applicator need not obtain an NPDES permit. However, chemical pesticide residuals are
pollutants as applied if they are discharged from a point source for which NPDES permits are
required. Biological pesticides, on the other hand, are always considered a pollutant under the
CWA regardless of whether the application results in residuals or not and require an NPDES
permit for all discharges of pollutants from a point source.

As a result of the Court's decision to vacate the 2006 NPDES Pesticides Rule, after
October 31, 2011 NPDES permits are required for discharges to waters of the United States of

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

biological pesticides, and of chemical pesticides that leave a residue. EPA and all NPDES-
authorized states and territories have developed and are implementing NPDES permits for
pollutant discharges resulting from pesticide applications. EPA Regional offices and state
NPDES authorities may issue additional general permits or individual permits if appropriate.

II. Structure of the Draft 2021 PGP
1. General

This permit is written for the many specific areas of the country for which EPA remains the
NPDES permitting authority. The permit is constructed in such a way that each Region will sign
and issue the final PGP and include in that issuance CWA Section 401 certification language for
areas in their Region covered by the permit. Specifically, the permit provides coverage for
certain point source discharges of pollutants that occur in areas not covered by an authorized
state NPDES permit program and includes specific areas (e.g., states, territories, Indian Country,
or federal facilities) in all ten EPA Regions. The complete list of areas of geographic coverage of
this permit, along with the NPDES permit numbers are listed in Appendix C of the draft 2021
PGP.

States and territories that are authorized to issue NPDES permits will continue to
administer their own NPDES permits to cover such discharges of pollutants. Nothing in the
federal regulations precludes a state from adopting or enforcing requirements in their own
permits that are appropriate to address discharges of pollutants in their state or are more stringent
or more extensive than those required by EPA under the NPDES regulations. See CWA section
510. In fact, the CWA is meant to serve as a baseline for state environmental protection. The
CWA and corresponding NPDES regulations require that permits, at a minimum, include the
requirements detailed in 40 CFR 122.44 (but not necessarily in the same way as in this permit).
States are free to incorporate additional or different requirements that they feel are appropriate to
protect water quality. Similarly, how EPA and states interpret information from which permit
requirements are developed may differ. For example, the regulations, as written at 40 CFR
122.44(i) specify that monitoring requirements be included to assure compliance with permit
limitations. One permit writer may make a best professional judgment (BPJ) determination that
monitoring of discharges of pollutants reasonably should occur during pesticide application
while a second permit writer may make a BPJ determination that monitoring of discharges of
pollutants should reasonably be performed after pesticide application. It is reasonable that the
two different permit writers may come to different conclusions about how best to incorporate this
requirement into the permit.

Throughout the fact sheet (and permit), EPA uses consistent terms when referring to what
activity or discharge of pollutants will be eligible for coverage and who will be responsible to
comply with the terms of the permit. Specifically, the permit holder is referred to as the
"Operator." This term has a similar meaning to the term "permittee" which is also used in the
fact sheet; generally, the term permittee is specific to the period of time that an Operator or
contractor is actually covered under the permit. More details on how an Operator may obtain
permit coverage and the applicable permit requirements are provided in Part III of the fact sheet.

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

The permit is divided into nine parts: (1) Coverage Under This Permit, (2) Technology-
Based Effluent Limitations, (3) Water Quality-Based Effluent Limitations, (4) Monitoring, (5)
Pesticide Discharge Management Plan, (6) corrective action, (7) Recordkeeping and Annual
Reporting, (8) EPA contact information and mailing addresses, and (9) Permit Conditions
Applicable to Specific States, Indian Country, or Territories. Additionally, the permit includes
nine appendices with additional conditions and guidance for permittees: (A) Definitions,
Abbreviations, and Acronyms, (B) standard permit conditions, (C) Areas Covered, (D) Notice of
Intent Form, (E) Notice of Termination Form, (F) Pesticide Discharge Evaluation Worksheet,
(G) Annual Report Template, (H) Adverse Incident Report Template, and (I) Endangered
Species Procedures.

Operators should carefully read each part of the permit to assess whether or what portion of
the requirements in each part may apply to their activities. As will be discussed in more detail in
Part III of the fact sheet, the permit establishes different requirements for different types of
pesticide use patterns, different types of Operators, and different sizes of areas treated and
managed for the control of pests. The organization of the permit is intended to clarify the
applicable requirements for Operators to the greatest extent possible.

2. Conformance to Court Decisions

Similar to the 2016 PGP, EPA has structured this draft 2021 PGP to conform to relevant
court decisions. One of these cases held that because the terms of the Nutrient Management Plan
(NMP) employed by concentrated animal feeding operations (CAFO) imposed restrictions on
discharges of pollutants, those restrictions amounted to effluent limitations that needed to be
made part of the permit and to be subject to public and permit writer review. Waterkeeper
Alliance, Inc. v. EPA, 399 F.3d 486 (2nd Cir. 2005). In this respect, this permit is different from
the CAFO requirements. In this permit, EPA explicitly establishes effluent limitations in Parts 2
and 3 that are independent of any documentation and recordkeeping requirements regarding
implementation of the limitations. In a separate part of the permit (Part 5) there is a requirement
to develop a Pesticide Discharge Management Plan (PDMP). The PDMP is not a limitation and
does not itself impose requirements on discharges of pollutants. These are already imposed by
the limitations in Parts 2 and 3. The PDMP is rather a tool for those Operators who are defined as
Decision-makers to document, among other things, how Pest Management Measures will be
implemented to comply with the permit's effluent limitations.

Effluent Limitations in the Draft 2021 PGP

Part 2 of the draft 2021 PGP contains the technology-based effluent limitations. Part 3 of
the draft 2021 PGP contains the water quality-based effluent limitations. These Parts of the
permit contain effluent limitations, defined in the CWA as restrictions on quantities, rates, and
concentrations of constituents that are discharged. CWA section 502(11). Violation of any of
these effluent limitations constitutes a violation of the permit. As is described in more detail in
Part III.2 of the fact sheet, under the CWA these effluent limitations can be narrative rather than
numeric.

The technology-based effluent limitations set forth in Part 2 of the draft 2021 PGP require
the Operator to minimize the discharge of pollutants to waters of the United States from the

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U.S. Environmental Protection Agency	Draft 2021 NPDES Pesticide General Permit Fact Sheet

Note: This document is aprepublication version, signed by all 10 U.S. EPA Regions on December 14, 2020. EPA is
submitting it for publication in the Federal Register. We have taken steps to ensure the accuracy of this version, but
it is not the official version.

application of pesticides. Consistent with the control level requirements of the CWA, the term
"minimize" means to reduce and/or eliminate pollutant discharges to waters of the United States
through the use of Pest Management Measures to the extent technologically available and
economically achievable and practicable for the category or class of point sources covered under
the permit, taking into account any unique factors relating to the Operators to be covered under
the permit. The technology-based effluent limitations section is divided into two parts. The first
part applies to all Applicators and addresses the general requirement to minimize discharges
from the application of pesticides. In this part, all Applicators must minimize discharges of
pollutants by using only the amount of pesticide product per application and frequency of
pesticide applications necessary to control the target pest, performing regular maintenance
activities, calibrating and cleaning/repairing application equipment, and assessing weather
conditions in the treatment area. The second part requires certain Decision-makers to implement
pest management measures that involve the following: (1) identifying and assessing the pest
problem; (2) assessing effective pest management; and (3) following specified procedures for
pesticide application (see Part 2.2 of the draft 2021 PGP).

In addition to the technology-based effluent limitations, Part 3 of the draft 2021 PGP
contains the water-quality-based effluent limitations. The Operator must control its discharge of
pollutants as necessary to meet applicable water quality standards. Any discharge of pollutants
that results in an excursion of any applicable numeric or narrative EPA-approved state, territory,
tribal or EPA-promulgated water quality standard is prohibited. In general, based on the data
included in the record and the additional requirements in the permit, in addition to FIFRA's
requirements and the data and information upon which FIFRA registrations are based, EPA
expects that compliance with the technology-based effluent limitations and other terms and
conditions in the permit will meet applicable water quality-based effluent limitations. To date,
after over eight years of implementation of the prior permits, EPA does not have any evidence in
the record that the existing and prior permits are causing water quality problems. However, if at
any time the Operator or EPA determines that the discharge of pollutants causes or contributes to
an excursion of applicable water quality standards, the Operator must take corrective actions as
required in Part 6 of the draft 2021 PGP, and document and report the excursion(s) to EPA as
required in Part 7 of the draft 2021 PGP. Furthermore, consistent with Parts 3.0 and 6.3 of the
draft 2021 PGP, EPA may impose additional water quality-based limitations on a site-specific
basis, or require the Operator to obtain coverage under an individual permit, if information in an
NOI, required reports, or from other sources indicates that, after meeting the technology-based
limitations in the permit, the discharges of pollutants are not controlled as necessary to meet
applicable water quality standards. EPA also notes that among the eligibility requirements for
coverage under the permit are requirements that the permit does not cover discharges of any
pesticide into a water impaired by a substance which either is an active ingredient in that
pesticide or is a degradate of such an active ingredient, or into an Outstanding National Resource
Water (40 C.F.R. 131.12), often referred to as a "Tier 3 water" (except for pesticide applications
made to restore or maintain water quality or to protect public health or the environment that
either do not degrade water quality or only degrade water quality on a short-term or temporary
basis). These eligibility conditions further help EPA to issue a general permit while protecting
water quality on a water-body-specific basis.

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

Pesticide Discharge Management Plan (PDMP)

Distinct from the technology-based or water quality-based effluent limitation provisions in
the permit, Part 5.0 of the draft 2021 PGP requires Decision-makers that must submit an NOI
and that are large entities to prepare a PDMP to document the implementation of Pest
Management Measures being used to comply with the effluent limitations set forth in Parts 2.0
and 3.0 of the draft 2021 PGP. A large entity, as defined in Appendix A of the draft 2021 PGP, is
(1) a public entity that serves a population greater than 10,000 people or (2) a private enterprise
that exceeds the Small Business Administration "size standards" as provided in 13 CFR 121.201.

In general, Part 5.0 of the draft 2021 PGP requires that the following be documented in the
PDMP: (1) pesticide discharge management team information; (2) problem identification; (3)
pest management options evaluation; (4) response procedures pertaining to spills and adverse
incidents; (5) documentation to support eligibility considerations under other federal laws, and
(6) signature requirements. The PDMP must be kept up-to-date and modified whenever
necessary to document any corrective actions as necessary to meet the effluent limitations in the
permit.

The requirement to prepare a PDMP is not an effluent limitation because it does not restrict
quantities, rates, and concentrations of constituents that are discharged. CWA section 502(11).
Instead, the requirement to develop a PDMP is a permit "term or condition" authorized under
sections 402(a)(2) and 308 of the Act. Section 402(a)(2) states, "[t]he Administrator shall
prescribe conditions for [NPDES] permits to assure compliance with the requirements of
paragraph (1) of this subsection, including conditions on data and information collection,
reporting, and such other requirements as he deems appropriate." The PDMP requirements set
forth in the permit are terms or conditions under the CWA because the Operator is documenting
information on how it is complying with the effluent limitations (and inspection and evaluation
requirements) contained elsewhere in the permit. Thus, the requirement to develop a PDMP and
keep it updated is no different than other information collection conditions, as authorized by
section 402(a)(2), in other permits. Failure to have a PDMP, where required, is a violation of the
permit.1

While Part 2 of the draft 2021 PGP requires the Operator to select Pest Management
Measures to meet the effluent limitations in the permit, the Pest Management Measures
themselves described in the PDMP are not effluent limitations because the permit does not
impose on the Operator the obligation to comply with the PDMP; rather, the permit imposes on
the Operator the obligation to meet the effluent limitations prescribed in Parts 2.0 and 3.0 of the
draft 2021 PGP. Therefore, the Operator is free to change as appropriate the Pest Management
Measures used to meet the effluent limitations contained in the permit. This flexibility helps
ensure that the Operator is able to adjust its practices as necessary to ensure continued

1 This permit is also consistent with the decision in Texas Independent Producers and Royalty Owners
Assoc.. et. al. v. EPA. 410 F.3d 964 (7th Cir. 2005), where petitioners challenged EPA's issuance of the construction
general permit (CGP) that covers stormwater discharges. In that case, the Court found that neither the Stormwater
Pollution Prevention Plan (SWPPP) nor the Notices of Intent (NOIs) are permits or permit applications because they
do not amount to limits. 410 F.3d at 978. Further, the Court found that the permit requirement to develop a SWPPP
is not an effluent limitation. For the draft 2021 PGP, the PDMP serves a similar purpose as the CGP SWPPP.

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

compliance with the permit's effluent limitations. However, the permit also contains a
recordkeeping condition that requires that the PDMP be updated with any such changes in the
Operator's practices. See Part 5.2 of the draft 2021 PGP. Thus, if an Operator's on-the-ground
practices differ from what is in the PDMP, this would constitute a violation of the permit's
recordkeeping requirement to keep the PDMP up-to-date, and not per se a violation of the
permit's effluent limitations, which are distinct from the PDMP. EPA recognizes, however, that
because the PDMP documents how the Operator is meeting the effluent limitations contained in
the permit, not following through with actions identified by the Operator in the PDMP as the
method of complying with the effluent limitations in the permit is relevant to evaluating whether
the Operator is complying with the permit's effluent limitations.

Public Availability of Documents

Part 5.3 of the draft 2021 PGP requires that the Operator retain a copy of the current PDMP
at the address listed on the NOI and it must be immediately available, at the time of an onsite
inspection or upon request to EPA, state, tribal or local agencies governing wastewater
discharges of pollutants and/or pesticide applications, and representatives of the United States
Fish and Wildlife Service (FWS) or the National Marine Fisheries Service (NMFS). While not
required to be submitted to EPA, interested persons can request a copy of the PDMP through
EPA, at which point EPA will likely request the Operator to provide a copy of the PDMP. By
requiring members of the public to request a copy of the PDMP through EPA, the Agency is able
to provide the Operators with assurance that any Confidential Business Information that may be
contained within its PDMP is not released to the public. NOIs will be publicly available once
submitted through the NPDES eReporting Tool (NeT). The NOIs generally will be available to
the public for 10 days before permit coverage begins. During this time period, issues can be
raised with EPA, which has the authority to deny coverage.

3. Sharing of Responsibilities

This general permit was developed with the understanding that there may be more than one
responsible entity for a given discharge of pollutant. As structured, the permit provides for
sharing of responsibilities to meet the end goal of discharges of pollutants being in compliance
with permit requirements. The NPDES regulations state that "Operators" are responsible for
achieving permit compliance. Specifically, 40 CFR 122.21(b) clarifies that when an activity is
owned by one person, but it is operated by another person (e.g. contractor), it is the Operator's
duty to meet terms of the permit. EPA acknowledges, however, that in many instances the owner
may still perform Operator duties; as such, they may still be required to obtain permit coverage,
even in situations in which, for example, the owner hires a contractor to apply the pesticides to
control pests. The draft 2021 PGP includes a definition of "Operator" in Appendix A of the
draft 2021 PGP that is intended to clarify this point, focusing on the fact that Operator control
exists both at the "Decision-maker" level about how to control pests, including financial
considerations, as well as at the pesticide Applicator" level (such as calibration of pesticide
application equipment). In these instances, both Operators, i.e., the Decision-Maker and the
Applicator, are required to obtain NPDES permit coverage; however, the permit strives to
minimize any potential duplication of effort by identifying which Operator is responsible for
certain permit conditions. The permit clarifies these responsibilities by identifying whether EPA

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U.S. Environmental Protection Agency	Draft 2021 NPDES Pesticide General Permit Fact Sheet

Note: This document is aprepublication version, signed by all 10 U.S. EPA Regions on December 14, 2020. EPA is
submitting it for publication in the Federal Register. We have taken steps to ensure the accuracy of this version, but
it is not the official version.

expects these activities to be performed by all Operators, or just the Decision-maker or the
Applicator.

Entities such as subcontractors that are hired by an owner or other entity but are under the
supervision of such owner or entity generally are not Operators. Similarly, entities are likely not
an Operator if, for example, they own the land, but the activities are being performed outside of
their control (e.g., a public entity is spraying for mosquitoes over private property, or a private
party is spraying for weeds on public lands leased from the federal government).

EPA encourages Operators to use already prepared information and explore possible cost
savings by sharing responsibilities for implementing aspects of this permit. For example, a
mosquito control district may have developed something for their FIFRA program and they
could assume the overall coordination of an integrated pest management program while a hired
contractor may be responsible for minimizing the pollutant discharge and for site monitoring and
maintaining and calibrating pesticide application equipment. In instances where multiple
Operators are responsible for the discharge from larger pesticide application activities, some
form of written explanation of the division of responsibilities should be documented. However,
any and all Operators covered under the permit are still responsible for any violation that may
occur, though EPA may consider this written division of responsibilities when determining the
appropriate enforcement response to a violation.

III. Summary of Draft 2021 PGP Conditions
1. Coverage Under the Draft 2021 PGP
1.1 Eligibility

1.1.1 Activities Covered

The activities covered under this draft 2021 PGP remain unchanged from the 2016 PGP.
Only Operators meeting the eligibility requirements outlined in the draft 2021 PGP may be
covered under the permit. If an Operator does not meet the eligibility provisions described in Part
1.1 of the draft 2021 PGP, the Operator's point source discharges of pollutants to waters of the
United States2 from the application of pesticides will be in violation of the CWA, unless the
Operator has obtained coverage under another permit or the CWA exempts these discharges of
pollutants from NPDES permit requirements. The activities covered by this permit generally
include the use patterns and types of pest control activities described in the vacated 2006 NPDES
Pesticides Rule. Under CWA section 502(14), agricultural stormwater and irrigation return flow
are exempt from NPDES permits. Also, applications that do not reach waters of the United States
do not need permit coverage. Thus, the draft 2021 PGP covers the discharge of pollutants
(biological pesticides and chemical pesticides which leave a residue) to waters of the United
States resulting from the following use patterns: (1) Mosquito and Other Flying Insect Pest

2 For information on the definition of "waters of the United States" and litigation updates, see
https ://www. epa. gov/nwpr.

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

Control; (2) Weed and Algae Control; (3) Animal Pest Control; and (4) Forest Canopy Pest
Control, as summarized below:

Mosquito and Other Flying Insect Pest Control

This use pattern includes the application, by any means, of chemical and biological
insecticides and larvicides into or over water to control insects that breed or live in, over,
or near waters of the United States. Applications of this nature usually involve the use of
ultra-low volume sprays or granular larvicides discharged over large swaths of mosquito
breeding habitat and often are performed several times per year.

Weed and Algae Pest Control

This use pattern includes the application, by any means, of contact or systemic herbicides
to control vegetation and algae (and plant pathogens such as fungi) in waters of the
United States and at water's edge, including ditches and/or canals. Applications of this
nature typically are single spot pesticide applications to control infestations or staged
large scale pesticide applications intended to control pests in several acres of waterway.
Pesticide applications in a treatment area may be performed one or more times per year to
control the pest problem.

Animal Pest Control

This use pattern includes the application, by any means, of pesticides into waters of the
United States to control a range of animal pests for purposes such as fisheries
management, invasive species eradication, or equipment operation and maintenance.
Applications of this nature are often made over an entire or large portion of a waterbody
as typically the target pests are mobile. Multiple pesticide applications to a waterbody for
animal pest control are often made several years apart.

Forest Canopy Pest Control

This use pattern includes pest control projects in, over, or to forest canopies (aerially or
from the ground) to control pests in the forest canopy where waters of the United States
exist below the canopy. Applications of this nature usually occur over large tracts of land
and are typically made in response to specific pest outbreaks. EPA understands that for
this use pattern pesticides will be unavoidably discharged into waters of the United States
in the course of controlling pests over a forest canopy as a result of pesticide application.
These pests are not necessarily aquatic (e.g., airborne non-aquatic insects) but are
detrimental to industry, the environment, and public health. Note: EPA recognizes that
mosquito adulticides are applied to forest canopies, and this application is covered under
the "Mosquito and Other Flying Insect Pest Control" use pattern.

In the 2006 NPDES Pesticides Rule, EPA expressly noted that the rule did not cover either
"spray drift" - the airborne movement of pesticide sprays away from the target application site
into waters of the United States - or applications of pesticides to terrestrial agricultural crops
where runoff from the crop, either as irrigation return flow or agricultural stormwater, discharges
into waters of the United States.

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U.S. Environmental Protection Agency	Draft 2021 NPDES Pesticide General Permit Fact Sheet

Note: This document is aprepublication version, signed by all 10 U.S. EPA Regions on December 14, 2020. EPA is
submitting it for publication in the Federal Register. We have taken steps to ensure the accuracy of this version, but
it is not the official version.

Consistent with the 2006 NPDES Pesticides Rule and the 2016 PGP, this draft 2021 PGP
does not cover spray drift resulting from pesticide applications. Instead, to address spray drift,
EPA is actively engaged in several initiatives to help minimize pesticide drift problems such as:
(1) evaluating potential for drift as a routine part of pesticides risk assessments; (2) in
collaboration with experts, improving scientific models and methods for estimating drift and
risks from drift; (3) strengthening labeling for new pesticides and when re-evaluating older
pesticides; (improving the clarity and enforceability of product label directions and drift
management restrictions; and (4) promoting applicator education and training programs. More
information on EPA's work on reducing pesticide drift is available at
https://www.epa.gov/reducing-pesticide-drift.

Irrigation return flow (such as runoff from a crop field due to irrigation of that field) and
agricultural stormwater runoff do not require NPDES permits, as exempted from the definition of
point source under section 502(14) of the CWA. Neither the 2006 NPDES Pesticides Rule, the
Sixth Circuit Court vacatur of that rule, nor any version of the PGP have changed in any way the
determination of whether certain types of stormwater discharges are required to obtain permit
coverage, or under which permit coverage is required. This is true whether the discharge of
pollutants contains pesticides or pesticide residues resulting from the application of pesticides. In
particular, non-agricultural stormwater that may contain pesticides is required to obtain NPDES
permit coverage if required under section 402(p) of the Clean Water Act. Existing stormwater
permits for construction, industrial activity, and regulated municipal separate storm sewer
systems (MS4s) already address pesticides in stormwater from those sources. Thus, stormwater
is either: (a) already subject to NPDES permit requirements pursuant to section 402(p) of the
CWA or (b) is a discharge for which NPDES permit coverage is not currently required under
section 402(p). The regulations that specify what types of stormwater require NPDES permits
can be found in 40 CFR §122.26 and 122.30-122.37.

EPA determined that the four use patterns included in the draft 2021 PGP would
encompass the majority of pesticide applications that would result in point source discharges of
pollutants to waters of the United States and generally represent the use patterns intended to be
addressed by the 2006 rule that is now vacated. This permit does not cover, nor is permit
coverage required, for pesticides applications that do not result in a point source discharge of
pollutants to waters of the United States, such as for the purpose of controlling pests on
agricultural crops, forest floors, or range lands. However, the application of herbicides in waters
of the United States and the control of pests on plants grown in waters of the United States, such
as perennial obligate hydrophytes, is within the permit's scope of coverage. This fact sheet does
not identify every activity which may involve a point source discharge of pollutants to waters of
the United States that would require a permit; rather, the fact sheet focuses on the activities for
which coverage under the draft 2021 PGP is available. The existence of this general permit does
not alter the requirement that discharges of pollutants to waters of the United States that are not
covered by this permit be covered by an individual permit or another general permit.

Scope of Permit

The Sixth Circuit Court of Appeals found that if a chemical pesticide leaves any excess or
residue after performing its intended purpose, such excess or residue would be considered a

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

pollutant under the CWA. The Court also found that, unlike chemical pesticides, not only would
the residue and excess quantities of a biological pesticide be considered a pollutant, but so too
would the biological pesticide itself under the CWA.

As defined in 40 CFR 122.2, "Pesticide residue for the purpose of determining whether
an NPDES permit is needed for discharges of pollutants to waters of the United States from
pesticide application, means that portion of a pesticide application that is discharged from a point
source to waters of the United States and no longer provides pesticidal benefits. It also includes
any degradates of the pesticide."

A permit would not be necessary if it is determined that pesticide residual does not enter
waters of the United States. The Operator applying pesticides with a discharge to waters of the
United States can support their determination with scientific data. Such data should show what
level of the pesticide can be detected in water, and at what level in water the pesticide provides a
pesticidal benefit. Such data should address the properties of the chemical pesticide under
different water conditions (e.g., different pH, organic content, temperature, depth, etc.) that
might affect the pesticide's properties.

EPA offers the following guidance with respect to the use patterns of chemical pesticides
covered by this general permit.

1. If the application of a chemical pesticide is made over waters of the United States to
control pests over the water, any amount of the pesticide that falls into waters of the
United States is "excess" pesticide and would require coverage by an NPDES permit.

2. If the application of a chemical pesticide is made into waters of the United States to
control a pest in such waters, any amount of the pesticide that remains in those waters
and no longer provides any pesticidal benefit is a "residual" and would require
coverage by an NPDES permit. See 40 CFR 122.2 for the definition of pesticide
residue.

3. This permit authorizes discharges of pollutants associated with four categories of
pesticide application activities: mosquito and other flying insect pest control, weed and
algae pest control, animal pest control, forest canopy pest control. As noted above, only
point source discharges of pollutants to waters of the United States require a permit,
and it is beyond the scope of this fact sheet to identify all specific activities that do or
do not require a permit. However, to the extent that activities that fall within the four
covered categories require a permit, they can be authorized by this general permit if all
eligibility requirements are met. For two of the categories, weed and algae pest control
and animal pest control, the permit specifies that covered activities include applications
to control pests "in water and at water's edge." EPA intends for the phrase "at water's
edge" to allow coverage of activities targeting pests that are not necessarily "in" the
water but are near the water such that control of the pests results in a point-source
discharge of pollutants to waters of the United States. The category forest canopy pest
control is for applications to a forest canopy. EPA intends that this can include both
mature and immature forest canopies, including canopies that may not be continuously
connected, where control of pests associated with the canopy {i.e., branches and leaves

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

of the trees) results in a point source discharges of pollutants to waters of the United
States.

For purposes of this permit, EPA is relying on existing regulatory definitions in 40 CFR
174.3 and 158.2100(a) developed under FIFRA to define the term "biological pesticides." For
purposes of this permit, EPA identifies biological pesticides (also called "biopesticides" under
FIFRA regulations) to include microbial pesticides [40 CFR 158.2100(b)], biochemical
pesticides [40 CFR 158.2000(a)(1)] and plant-incorporated protectants. [40 CFR 174.3]

EPA recognizes that there are many site-specific situations which will determine whether a
pesticide application operation needs permit coverage. EPA is not attempting to define all such
situations in this fact sheet. Additionally, any pesticide application activities that do not fall
within the four use patterns covered by this permit will require coverage under some other
NPDES permit if those activities result in point source discharges of pollutants to waters of the
United States. However, the Agency does want to make it clear that to the extent pesticide
application operations need permit coverage, this permit is available for the four pesticide use
categories.

Additionally, as described in Part 1.4 of the fact sheet, the permit does not cover discharges
of pollutants that, by law, are not required to obtain NPDES permit coverage. Of note, the CWA
specifically excludes from the definition of point source, "agricultural stormwater discharges and
return flow from irrigated agriculture." Nothing in this permit changes the effect of those
statutory exemptions.

See Appendix D of the fact sheet for discussion on the cost impact and the universe of
Operators covered under this permit.

1.1.2 Limitations on Coverage

1.1.2.1 Discharges of Pollutants to Water Quality Impaired Waters

This permit specifies eligibility requirements for coverage under this general permit for
discharge of pollutants to impaired waters. The requirements remain unchanged from the 2011
PGP and 2016 PGP. Coverage under the permit is only available for certain discharges of
pollutants to impaired waters. Discharges of pollutants to waters which are impaired for a
substance which is not an active ingredient in that pesticide or a degradate of such an active
ingredient are eligible for coverage. Discharges of pollutants to waters impaired for temperature
or some other indicator parameter, or for physical impairments such as "habitat alteration" are
also eligible for draft 2021 PGP coverage, unless otherwise notified by EPA. Conversely, the
permit is not available for the discharge of any pesticide to water that is impaired for a substance
that is an active ingredient in that pesticide or a degradate of such an active ingredient. For
example, application of the pesticide copper sulfate to a waterbody impaired for either copper or
sulfates would not be eligible for coverage under this permit, because copper sulfate can degrade
into these two substances. In this instance, the Operator would have to choose between obtaining
coverage under an individual permit for such a discharge or selecting some other means of pest
management, e.g., using mechanical means or a different pesticide active ingredient.

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

For this permit, EPA determined that it does not have information warranting a limitation
for all impaired waters regardless of the impairment. In fact, the application of a pesticide to
water in some instances actually improves the quality of the water, such as when used to control
algae growth that can deplete oxygen levels in water. It is important to note that this permit
allows EPA, based on additional information, to opt not to approve coverage under the draft
2021 PGP, or at a later date to require an Operator covered under the draft 2021 PGP to apply for
coverage under an individual permit.

For purposes of this permit, impaired waters are those that have been identified by a state,
territory, tribe, or EPA pursuant to Section 303(d) of the CWA as not meeting applicable water
quality standards. Impaired waters for purposes of the draft 2021 PGP include both waters with
EPA-approved and EPA-established Total Maximum Daily Loads (TMDLs), and those for
which EPA has not yet approved or established a TMDL. (A list of impaired waters, along with
the pollutants or pollution identified as the cause of the impairment is available at
https://www.epa.gov/tmdn. Since the 303(d) list provides the most readily-available evidence of
impairment, Operators should use it when deciding whether their discharges of pollutants meet
the eligibility requirements regarding waterbodies impaired for specific pesticides. Thus, these
requirements will further ensure protection of water quality.

Also, several states have listed waters as impaired for "pesticides" but have not identified
the specific pesticide for which the waterbody is impaired. Without additional information
suggesting that the waterbody is impaired for a specific active ingredient or degradate of that
active ingredient, EPA is providing coverage under this permit for discharges of pollutants to
waters that are impaired generally for "pesticides." The Agency expects that as these impaired
waters are further assessed, specific pesticides or classes of pesticides will be identified as the
cause of the impairment, at which point dischargers will no longer be eligible to obtain permit
coverage under the draft 2021 PGP for discharges of those named pesticide active ingredients or
degradates of such. Additional discussion of existing impairments identified for which pesticides
are identified as the source of the impairment is provided in Part III.3 of the fact sheet.

1.1.2.2 Discharges of Pollutants to Waters Designated as Tier 3 for Antidegradation
Purposes

This permit specifies requirements for coverage under this general permit for discharges of
pollutants to Tier 3 waters. These waters are called "Outstanding National Resource Waters" in
the regulations. 40 C.F.R. 131.12. The requirements remain unchanged from the 2011 PGP and
2016 PGP. This permit provides coverage for discharges of pollutants made to restore or
maintain water quality or to protect public health or the environment that either do not degrade
water quality or only degrade water quality on a short-term or temporary basis. This is consistent
with EPA's longstanding view that "[sjtates may allow some limited activities which result in
temporary and short-term changes in water quality. Such activities are considered to be
consistent with the intent and purpose of [a Tier 3 water]." 48 FR 51400, 51403 (1983).

States and tribes provide the most stringent level of antidegradation protection, i.e., Tier 3
protection. These waters are often regarded as the highest quality waters of the United States, but
the Tier 3 designation also provides special protection for waters of exceptional ecological
significance, i.e., those which are important, unique, or sensitive ecologically. Except for certain

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

temporary changes, Tier 3 protection means that water quality cannot be lowered in such waters.
In broad terms, EPA's view of "temporary" is weeks and months, not years. States and tribes
make the decision of which water bodies to designate as Tier 3. A list of Tier 3 waters in areas
where the draft 2021 PGP is available can be accessed on the Internet at
https://www.epa.gov/npdes/pesticide-permitting.

This permit requires additional documentation and reporting for discharges of pollutants to
Tier 3 waters. See Part 5.1.2 of the draft 2021 PGP. Any Decision-maker planning to discharge
to a Tier 3 water must submit a Notice of Intent (NOI) consistent with Part 1.2.2 of the draft
2021 PGP. NOIs for such discharges of pollutants are required to identify the Tier 3 water by
name, and provide a discussion of the environmental problem and demonstration that the
pollutant discharge is necessary to protect water quality, the environment, and/or public health.
This NOI requirement includes the requirement for any Decision-maker already covered under
the draft 2021 PGP who wants to discharge to a Tier 3 water at a later date, to submit an updated
NOI containing the information identified above for discharges of pollutants to Tier 3 waters.
Additionally, NOIs for any discharges of pollutants to Tier 3 waters must be submitted at least
10 days before beginning discharge unless discharges of pollutants are in response to a Declared
Pest Emergency Situation, in which case, an NOI is due for such discharges of pollutants no later
than 15 days after beginning discharge (if water contains NMFS Listed Resource of Concern) or
30 days after beginning discharge (if no NMFS Listed Resource of Concern). Decision-makers
are required to submit an NOI consistent with the earliest due date identified in Table 1-2 of the
draft 2021 PGP.

Of note, some states have adopted alternative approaches to designating Tier 2 or Tier 3
waters. These are collectively referred to as "Tier 2.5" waters since they fall between Tiers 2 and
3 in terms of characteristics and regulations supporting them. Tier 2.5 waters are commonly
described as providing protection more stringent than Tier 2 but allowing some added flexibility
that a Tier 3 water would not. Refer to Memorandum from William Diamond (Former Director,
Standards and Applied Science Division) to Victoria Binetti (Chief, Region III, Program and
Support Branch), June 13, 1991. Examples of Tier 2.5 waters exist in Massachusetts, which
designates "outstanding resource waters" (ORWs). These waters have exceptional sociologic,
recreational, ecological and/or aesthetic values and are subject to more stringent requirements
under both the Massachusetts Water Quality Standards and the Massachusetts Stormwater
Management Standards. ORWs include vernal pools certified by the Natural Heritage Program
of the Massachusetts Department of Fisheries and Wildlife and Environmental Law
Enforcement, all Class A designated public water supplies with their bordering vegetated
wetlands, and other waters specifically designated. The draft 2021 PGP does not restrict
eligibility for discharges of pollutants to Tier 2.5 waters.

1.1.2.3 Discharges of Pollutants Currently or Previously Covered by Another Permit

Part 1.1.2.3 of the draft 2021 PGP describes situations where an Operator is ineligible for
coverage under this permit because of coverage under another permit. The permit provisions
remain unchanged from the 2011 PGP and 2016 PGP. These include discharges of pollutants
currently covered under an NPDES permit and discharges of pollutants from activities where the
associated NPDES permit has been or is in the process of being denied, terminated, or revoked

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by EPA (although this last provision does not apply to the routine reissuance of permits every
five years).

1.1.2.4 Endangered and Threatened Species and Critical Habitat Protection

The draft 2021 PGP specifies procedures to assist in protecting federally-listed endangered
and threatened species and federally designated critical habitats under the Endangered Species
Act (ESA). These procedures are from EPA's 2016 PGP. EPA is currently in consultation with
the Services (National Marine Fisheries Service (NMFS) and United States Fish and Wildlife
Service (FWS)) for the reissuance of this permit. Based on the results of consultation with the
Services, EPA may include additional or altered conditions in the final permit.

The limitations described below reflect requirements that were added in the 2016 PGP
following formal consultation with NMFS and its issuance of a Biological Opinion on October
17, 2016: The provisions described below are designed to ensure that discharges of pollutants
covered under the draft 2021 PGP are not likely to adversely affect NMFS Listed Resources of
Concern, except as provided in Criterion B, C, and, for 60 days, D, in Part 1.1.2.4 of the draft
2021 PGP. These permit provisions include eligibility criteria for permit coverage as well as
requiring compliance with technology-based effluent limitations in Part 2.2 of the draft 2021
PGP and recordkeeping and reporting requirements for Decision-makers with discharges of
pollutants to waters of the United States containing NMFS Listed Resources of Concern.

The provisions described below only apply to Decision-makers subject to the draft 2021
PGP that are located in the limited areas where the NMFS Listed Resources of Concern, as
defined in Appendix A of the draft 2021 PGP, are present. The 48 states and territories
authorized to administer their own NPDES programs are not bound by the same ESA
consultation requirements that bind EPA in the issuance of its permits, and thus, these permit
terms are not federal NPDES requirements that the NPDES-authorized states must adopt. Many
states have their own endangered species-related requirements under state law, and these may be
reflected in state permits.

Part 1.1.2.4 of the draft 2021 PGP requires Operators to certify that they are eligible for
permit coverage under one of the six criteria (A-F) as follows:

Criterion A. Pesticide application activities will not result in a point source discharge to
one or more waters of the United States containing National Marine Fisheries Service (NMFS)
Listed Resources of Concern, as defined in Appendix A, for this permit. In this case, no further
certification is necessary. Decision-makers not otherwise required to submit an NOI are not
required to do so merely to check Criterion A. However, Decision-makers who must submit an
NOI anyway should check Criterion A if they do not discharge to a water of the United States
containing NMFS Listed Species of Concern.

Criterion B. Pesticide application activities will discharge to one or more receiving waters
of the United States containing NMFS Listed Resources of Concern, as defined in Appendix A,
but consultation with NMFS under section 7 of the ESA has been concluded for pesticide
application activities covered under this permit. Consultations can be either formal or informal,
and would have occurred only as a result of a separate federal action. The consultation addressed

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

the effects of pesticide discharges and discharge-related activities on federally-listed threatened
or endangered species and federally-designated critical habitat, and must have resulted in either:

i. A biological opinion from NMFS finding no likely jeopardy to listed species and no
destruction/adverse modification of federally-designated critical habitat; or

ii. Written concurrence from NMFS with a finding that the pesticide discharges and
discharge-related activities are not likely to adversely affect federally-listed species or
federally-designated critical habitat.

Criterion C. Pesticide application activities will discharge to one or more waters of the
United States containing NMFS Listed Resources of Concern, as defined in Appendix A, but any
"take" of these resources associated with such pesticide application activities has been authorized
through NMFS' issuance of a permit under section 10 of the ESA, and such authorization
addresses the effects of the pesticide discharges and discharge-related activities on federally-
listed species and federally-designated critical habitat. (The term "take" means to harass, harm,
pursue, hunt, shoot, wound, kill, trap, capture, or collect, or to attempt to engage in any such
conduct. See Section 3 of the Endangered Species Act, 16 U.S.C. § 1532(19).)

Criterion D. Pesticide application activities were, or will be, discharged to one or more
waters of the United States containing NMFS Listed Resources of Concern, as defined in
Appendix A, but only in response to a Declared Pest Emergency Situation. Decision-makers
must provide EPA with their rationale supporting the determination whether the discharge is
likely to adversely affect NMFS Listed Resources of Concern, including the description of
appropriate measures to be undertaken to avoid or eliminate the likelihood of adverse effects.

Criterion E. Pesticide application activities for which permit coverage is being requested
in the NOI will discharge to one or more waters of the United States containing NMFS Listed
Resources of Concern, as defined in Appendix A. Eligible discharges include those where the
Decision-maker includes in the NOI written correspondence from NMFS that pesticide
application activities performed consistent with appropriate measures will avoid or eliminate the
likelihood of adverse effects. Eligibility under this criterion is contingent upon the Decision-
maker following the measures described in correspondence from NMFS designed to avoid or
eliminate the likelihood of adverse effects.

Criterion F. Pesticide application activities for which permit coverage is being requested
in the NOI will discharge to one or more waters of the United Stated containing NMFS Listed
Resources of Concern, as defined in Appendix A. Eligible discharges include those from
pesticide application activities that are demonstrated by the Decision-maker as not likely to
adversely affect NMFS Listed Resources of Concern or that the pest poses a greater threat to the
NMFS Listed Resources of Concern than does the discharge of the pesticide. Decision-makers
must provide EPA with their documentation demonstrating the basis for their finding.

Criteria E and F, at least 30 days prior to beginning to discharge, require an Operator to
demonstrate:

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U.S. Environmental Protection Agency	Draft 2021 NPDES Pesticide General Permit Fact Sheet

Note: This document is aprepublication version, signed by all 10 U.S. EPA Regions on December 14, 2020. EPA is
submitting it for publication in the Federal Register. We have taken steps to ensure the accuracy of this version, but
it is not the official version.

-	Pesticides being discharged or to be discharged are known not to cause adverse
effects, or are or will be discharged at concentrations determined not to cause
adverse effects, to NMFS Listed Resources of Concern (Criterion F), or

-	NMFS Listed Resources of Concern are or will not be exposed to pesticide
pollutants produced by the discharge (e.g., species will not occur in the discharge
area during that time of year, the species will not be present in the hydrologic unit
in which the discharge will occur, the species is not present because of the presence
of the pest being controlled, etc) (Criterion F), or

Other considerations that demonstrate the discharge is not likely to adversely affect
NMFS Listed Resources of Concern (Criterion F), or

They have obtained written correspondence from NMFS indicating that pesticide
application activities performed consistently with appropriate measures will avoid
or eliminate the likelihood of adverse effects to Listed Resources of Concern.
Eligibility under this criterion is contingent upon the Decision-maker following the
measures described in correspondence from NMFS designed to avoid or eliminate
the likelihood of adverse effects (Criterion E).

Any Decision-maker planning to discharge pollutants to waters of the United States
containing NMFS Listed Resources of Concern, as defined in Appendix A of the draft 2021
PGP, must submit a Notice of Intent consistent with Part 1.2.2 of the draft 2021 PGP. The
specific requirements of the draft 2021 PGP NOI are identified in the NOI form provided in
Appendix D of the draft 2021 PGP. Also, refer to Appendix I of the draft 2021 PGP for the ESA
Review Procedures to determine eligibility prior to submittal of the NOI. This NOI requirement
includes the requirement for any Decision-maker already covered under the permit who
discharges pollutants to any waters of the United States containing NMFS Listed Resources of
Concern, as defined in Appendix A of the draft 2021 PGP, that were not identified in a
previously submitted NOI, to submit an updated NOI containing the information identified in
Appendix D of the draft 2021 PGP. Additionally, NOIs for any discharges of pollutants to waters
of the United States containing NMFS Listed Resources of Concern, as defined in Appendix A
of the draft 2021 PGP, must be submitted at least 30 days before beginning discharge. EPA may
authorize certain discharges of pollutants in less than 30 days, but no fewer than 10 days, for any
discharges of pollutants under Criterion B, C, or E of Part 1.1.2.4 of the draft 2021 PGP. Where
eligibility is determined consistent with Criterion D, response to a Declared Pest Emergency
Situation, an NOI is due for such discharges of pollutants no later than 15 days after beginning
discharged.

1.2 Authorization to Discharge Pollutants Under this Permit

1.2.1 How to Obtain Authorization

The NPDES general permit regulations, at 40 CFR § 122.28(b)(2), require that Operators
submit an NOI to obtain coverage under an existing general permit for which that discharge is

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eligible. However, those regulations, at §122.28(b)(2)(v), provide that at the discretion of the
Director (which, for the draft 2021 PGP, is EPA), certain discharges of pollutants can be
authorized under a general permit without submitting an NOI where EPA finds that an NOI
would be inappropriate for such discharges. In making such a finding, EPA must consider the
following criteria: the type of discharge; the expected nature of the discharge; the potential for
toxic and conventional pollutants in the discharges; the expected volume of the discharges of
pollutants; other means of identifying discharges of pollutants covered by the permit; and the
estimated number of discharges of pollutants to be covered by the permit.

This draft 2021 PGP is requiring submission of an NOI for certain discharges of pollutants
and is providing automatic coverage for certain other discharges of pollutants. The requirements
remain unchanged from the 2011 PGP and 2016 PGP. EPA is requiring submission of an NOI
for certain discharges of pollutants and is providing automatic coverage for certain other
discharges of pollutants for which EPA determined it would be inappropriate to require an NOI.
EPA is exempting Operators of pesticide research and development activities from the need to
submit an NOI because these activities are typically smaller and in many instances, are already
covered under FIFRA's section 5 (experimental use permits). Similarly, the draft 2021 PGP
exempts these activities from many requirements of the permit where such activities are
inconsistent with the research plan.

As discussed in Appendix D of the fact sheet, EPA expects a large number of discharges of
pollutants from the application of pesticides spanning a wide range of Operators and activities
will require NPDES permit coverage. Conditions and requirements in this permit remain largely
unchanged from the 2011 PGP and 2016 PGP. EPA's consideration of the regulatory criteria in
§122.28(b)(2)(v) is as follows based on information collected in the 2011 PGP development:

Type and Expected Nature of Discharge

All discharges of pollutants that would be authorized by the draft 2021 PGP involve either
(1) applications made directly into or over waters of the United States to control pests in or over
the water, or (2) applications to control pests near the water's edge such that pesticides will be
unavoidably deposited into waters of the United States. The draft 2021 PGP is structured by
pesticide use patterns. These use patterns were developed to include discharges of pollutants that
are similar in type and nature, and therefore represent the type of discharges of pollutants and
expected nature of the discharges of pollutants covered under this permit. The draft 2021 PGP
covers the four use patterns described in Part III. 1.1 of the fact sheet. EPA evaluated each use
pattern independently with the goal of identifying the significant activities resulting in discharges
of pollutants that should be covered under this draft 2021 PGP.

Potential for Toxic and Conventional Pollutants in the Discharge

EPA does not expect the potential for toxic and conventional pollutants in the discharges
from pesticides to vary among use patterns. EPA would expect, however, that the potential for
impacts from high concentrations of toxic or conventional pollutants in the discharge would be
smaller when fewer acres or linear feet are treated.

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

Expected Volume of Discharge

EPA also considered the expected volume of discharges of pollutants from each use
pattern. It is difficult to estimate the expected volume of discharges of pollutants for each use
pattern because Pest Management Measures used by Operators to meet the permit's technology
based effluent limitations may vary based on site-specific conditions. For example, the volume
of the discharge may vary depending on the specific pesticide being used, the intensity of the
pest pressure based on the specific pest problem, and the pest management strategy deemed to be
most effective for the pest problem. Moreover, minimizing the discharge of pollutant necessary
to manage pests successfully will vary among Operators depending on which Pest Management
Measures the Operator uses. Nonetheless, EPA expects that, in general, the volume of the
discharge will vary proportionally with the number of acres and linear miles treated.

Other Means to Identify Discharges of Pollutants

EPA also considered other means of identifying types of discharges of pollutants covered
by this permit. EPA may be able to identify pollutant discharges from Operator-submitted data,
ambient water sampling data, and other information submitted by pollutant dischargers pursuant
to federal or state law. However, EPA recognizes that the availability and quality of these data
may be limited and highly variable across the scope of activities and areas covered under the
draft 2021 PGP.

Number of Discharges of Pollutants

Last, EPA considered the estimated number of discharges of pollutants to be covered by
the permit. While the exact number of entities and thus the number of discharges of pollutants
that may be covered by the permit is unknown, EPA projects based on earlier estimates for the
PGP that the draft 2021 PGP will cover approximately 14,000 Operators per year in the areas
where EPA is the NPDES permitting authority. Of this total, a large majority represent
dischargers performing small pesticide applications that EPA considers to have very low
potential for impact. Thus, requiring an NOI from all dischargers would be a large burden of
little value for permitting authorities and permittees alike. See Appendix D of the fact sheet for
discussion on the universe of Operators covered under this permit.

In analyzing these regulatory criteria, the Agency gave particular weight to the expected
volume of the discharges of pollutants and the estimated number of discharges of pollutants to be
covered by the permit. After considering the universe of entities to be covered under the permit,
EPA found a logical break between entities applying pesticides to larger areas versus smaller
areas, and a difference between the types of entities generally responsible for performing such
pest control activities. As a result, NOI requirements are based on the size of areas treated and
the entity making the decision to perform pesticide applications. In addition, EPA identified a
need for additional information for any discharges of pollutants to outstanding national resource
waters (Tier 3 waters) and to waters of the United States containing NMFS Listed Resources of
Concern, as defined in Appendix A of the draft 2021 PGP, and is including NOI requirements for
all discharges of pollutants to these waters as well.

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

1.2.2 Decision-makers Required to Submit an NOI

To obtain authorization under the draft 2021 PGP, Operators (Decision-makers and
Applicators) must meet the Part 1.1 eligibility requirements of the draft 2021 PGP. If required by
Part 1.2.2 of the draft 2021 PGP, certain Decision-makers must submit a complete and accurate
NOI no later than the appropriate deadline described in Part 1.2.3 of the draft 2021 PGP.

Table 1-1 in Part 1.2.2 of the draft 2021 PGP identifies which Decision-makers are or will
be required to submit an NOI. Based on the analysis outlined in Part 1.2.1 above, For-Hire
Applicators, who are not Decision-makers as defined in Appendix A of the draft 2021 PGP, are
not required to submit NOIs. In addition, Decision-makers who apply pesticides to relatively
small areas are not required to submit NOIs (except for certain Operators that the Agency finds
have a significant role in pest control for public health and environmental protection and should
be expected to provide Agency notice of such activities). Nonetheless, EPA emphasizes that
even if an NOI is not required, Operators covered automatically are still subject to all applicable
requirements. EPA is requiring NOIs from the following types of Decision-makers:

- Decision-makers exceeding an annual treatment area threshold;

- Other Decision-makers specifically in the business of pest control;

- Decision-makers discharging pollutants to Tier 3 waters; and

- Decision-makers discharging pollutants to waters of the United States containing
NMFS Listed Resources of Concern, as defined in Appendix A of the draft 2021 PGP.

This permit provision remains unchanged from the 2011 PGP and 2016 PGP. A more
detailed discussion of EPA's rationale for requiring NOIs for these three categories of Decision-
makers follows.

NOIs for Decision-Makers Exceeding an Annual Treatment Area Threshold

During the 2011 PGP development, EPA developed annual treatment area thresholds for
each use pattern that will only require larger Operators applying pesticides to larger areas to
submit an NOI. To determine the appropriate annual treatment area thresholds that would trigger
the NOI requirement, EPA's Office of Water, Office of Chemical Safety and Pollution
Prevention and the ten EPA Regional Offices engaged in discussions with USD A, states as co-
regulators, and representatives from industry including pesticide registrants, applicators, and land
managers. Based on these discussions, the comments received during the 2011 PGP
development, and EPA's best professional judgment, EPA developed annual treatment area
thresholds that establish NOI requirements for applications to larger areas, which are believed to
have the greatest potential for impact to waters of the United States. EPA recognizes there are
many unknowns concerning the size, organization, and activities of the permitted universe.
Considerable variation in the availability of data and in the consistency of requirements across
regions and states resulted in EPA relying heavily on its best professional judgment in setting the
NOI annual treatment area thresholds for each of the use patterns. If a Decision-maker, otherwise
not required to submit an NOI, anticipates it will exceed an applicable annual treatment area
threshold during any time in a given calendar year of the permit cycle, that Decision-maker must
then submit an NOI consistent with the due dates described in Part 1.2.3 of the draft 2021 PGP.

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When calculating the size of the treatment area for comparing to an annual treatment area
threshold, EPA uses the term "at water's edge adjacent to waters of the United States" to identify
those areas where pesticides are applied to control pests that are present near water where a
portion of the pesticides will unavoidably be deposited to the water to target the pests. EPA's use
of the word "adjacent" in identifying these areas is merely used to identify areas near waters of
the United States and is not intended to mean "adjacent" as defined in regulation for use when
defining the term "waters of the United States."

To avoid duplication of submission, EPA is requiring that the Decision-maker responsible
for such applications be the Operator required to submit the NOI. So, where a Decision-maker
hires an Applicator to perform the pest control activities, the NOI is to be submitted by the
Decision-maker.

EPA's rationale for the annual treatment area threshold and Decision-makers required to
submit NOIs for each use pattern is as follows:

Mosquito Control and Other Flying Insect Pest Control

For Mosquitoes and Other Flying Insect Pests, the annual treatment area threshold has been
set at 6,400 acres of pesticide application to waters of the United States. Calculation of annual
treatment area for mosquito control should only count areas treated with adulticide. Larviciding
is not to be used in the calculations. EPA understands that the vast majority of mosquito control
and abatement districts in the United States manage areas significantly larger than this threshold
and may reasonably expect to exceed it during any given year. For instance, information from
the state of Florida on 49 independent mosquito control districts shows that 48 of the 49 districts
annually apply to more than 6,400 acres, which indicates that applications exceeding this area are
quite typical. Similarly, data provided in EPA's 2011 Economic Achievability Analysis of the
Pesticide General Permit (PGP) for Point Source Discharges from the Application of Pesticides
and included in the administrative record for this permit, show similar findings as in Florida.
Furthermore, the effective control of other aquatic breeding, flying insects, such as the blackfly,
necessitates applications that approach or exceed this threshold. Therefore, the threshold
appropriately captures most Decision-makers engaging in this use pattern.3 The Agency has
determined this appropriately captures those two classes of entities that either (1) are established
with a specific purpose of pest control or that (2) treat large enough areas to warrant notice to the
Agency.

Weed and Algae Control

For Weeds and Algae, the annual treatment area threshold has been set at 80 acres or 20
linear miles of pesticide application to canals and other waters of the United States. This
threshold has been set to capture Decision-makers treating relatively large portions of surface
waters and watersheds, such as water management districts, wildlife and game departments, and
some homeowner and lake associations. For example, Florida's South Florida Water

3 As discussed below, EPA also finds that even those mosquito control districts that treat areas below the
threshold should be required to submit NOIs, as these entities were created specifically for the control of pests and
should provide notice to the Agency of their activities.

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

Management District usually applies pesticides to 60 acres at a time hundreds of times per year
for various invasive plants on Florida's Lake Okeechobee. After reviewing the operations of
major irrigation and flood control systems as part of the initial PGP development, EPA expects
that generally, relatively large entities such as South Florida Water Management District,
California Department of Water Resources, or organizations with comparable resources are the
types of entities that manage 20 or more miles of engineered irrigation systems, and that this is a
reasonable limit to trigger the NOI requirement. The same rationale is applied to managers of
ditch and canal banks. Therefore, the threshold appropriately captures the relatively large
applications but excludes a significant number of small applications. Similar to mosquito control,
weed control districts, or similar pest control districts created specifically for the control of pests
that treat areas below the threshold, should be required to submit NOIs. As such, the permit
requires all weed control districts or similar pest control districts as well as any other Decision-
makers treating over the annual treatment area threshold to submit an NOI. The Agency has
determined that this appropriately captures those two classes of entities that either (1) are
established with a specific purpose of pest control or that (2) treat large enough areas to warrant
notice to the Agency.

Animal Pest Control

For Animal Pest Control, the annual treatment area threshold has been set at 80 acres or 20
linear miles of pesticide application to canals and other waters of the United States. Invasive and
nuisance aquatic animals are most commonly treated by public agencies such as departments of
fish and game, or utilities such as water management districts. The high mobility and prolific
breeding abilities that necessitate control of aquatic animals usually mean that pesticide
applications most often occur in the entirety or large portions of the water bodies they inhabit.
For example, fishery management applications using rotenone often occur in the entire lake, and
thus any similar application to a lake of more than 80 acres in area will trigger the annual
treatment area threshold. EPA expects that for this reason, only spot applications to eradicate
small emergent populations of sessile animals or applications to very small water bodies might
be excluded from an NOI requirement. Therefore, the threshold appropriately captures the
relatively large Decision-makers engaging in this use pattern.

Forest Canopy Pest Control

For Forest Canopy Pest Control, the annual treatment area threshold has been set at 6,400
acres of pesticide application to waters of the United States. Forest canopy pest suppression
programs are designed to blanket large tracts of terrain, throughout which Operators may not be
able to see waters of the United States beneath the canopy. EPA has set the annual treatment area
threshold for this use pattern with the understanding that this will exclude only the smallest
applications from the NOI requirement. These smaller applications generally occur on private
lands. Therefore, the threshold appropriately captures most Decision-makers engaging in this use
pattern, particularly public agencies managing large tracts of land.

NOIs for Certain Entities Regardless of the Annual Treatment Area Threshold

In addition to NOIs from Decision-makers treating the largest areas, EPA is also requiring
NOIs from certain other types of entities with land resource stewardship responsibilities that

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involve the routine control of pests. For these entities, the draft 2021 PGP requires NOIs
regardless of the size of the area treated. In general, EPA expects that in many instances these
entities will exceed one or more of the annual treatment area thresholds. Nonetheless, the
Agency finds that regardless of the size of the treatment area, any Agency for which pest
management for land resource stewardship is an integral part of the organization's operations
should also be required to submit NOIs. Such entities may include federal government agencies
such as the U.S. Forest Service (U.S. Department of Agriculture) and the Bureau of Land
Management (Department of the Interior), state government agencies such as natural resources
departments, or pest control districts. EPA's rationale for imposing the NOI requirement is
premised on these entities (public, quasi-public, and private) having as an integral responsibility
controlling pests. The specific entities required to submit NOIs regardless of whether an annual
treatment area threshold is exceeded are as follows:

Any Agency for which pest management for land resource stewardship is an integral part of the
organization's operations - Any agency that has pest control as an integral part of the
organization's operations or responsibilities is required to submit an NOI. Information in the
record indicates that many pest control activities performed by these entities will meet or exceed
the threshold requirement to submit an NOI. Even when these activities do not exceed the
thresholds, however, they are subject to the NOI requirement if the pesticide application is an
integral part of their operations and responsibilities. EPA also recognizes, however, that some of
these agencies may perform ad-hoc pest control on a small-scale that is not an integral part of the
organization's operations but rather incidental, for example, to its occupancy of a building.

Mosquito control districts (or similar pest control districts, such as vector control districts) - In
many parts of the country, state and territorial governments have established special districts for
the purpose of mosquito control. Generally, these districts treat large areas that would exceed
EPA's annual treatment area thresholds; however, EPA is requiring any such district, regardless
of the area treated, to submit an NOI.

Irrigation control districts (or other similar public or private entities supplying irrigation
waters) - In many parts of the country, special districts have been established for the purpose of
maintaining irrigation canals and ditches. Generally, these districts treat large areas that exceed
EPA's annual treatment area thresholds; however, EPA is requiring any such district, regardless
of the area treated, to submit an NOI.

Weed control districts (or other similar special purpose districts created with a responsibility of
pest control) - EPA is aware of some weed control districts created across the country with the
specific responsibility to control pests. The Agency has determined that these types of entities,
who perform pest management and control, as the primary function of their organization, should
provide notice to the Agency of such activities regardless of the size of the area treated.

NOIs for Discharges of Pollutants to Tier 3 Waters

Any Decision-maker requesting to discharge pollutants to Tier 3 waters may seek coverage
under the draft 2021 PGP provided that the discharge of pollutants is short-term or temporarily
lowers water quality due to pesticide applications that are necessary to protect the water quality,
environment, or public health. Any Decision-maker wanting coverage under the draft 2021 PGP

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U.S. Environmental Protection Agency	Draft 2021 NPDES Pesticide General Permit Fact Sheet

Note: This document is aprepublication version, signed by all 10 U.S. EPA Regions on December 14, 2020. EPA is
submitting it for publication in the Federal Register. We have taken steps to ensure the accuracy of this version, but
it is not the official version.

for such a discharge will be required to identify the Tier 3 water by name with authorization to
discharge pollutants to Tier 3 waters limited to only such named waters.

NOIs for Discharges of Pollutants to Waters of the United States Containing NMFS Listed
Resources of Concern, as Defined in Appendix A of the PGP

Any Decision-maker with any discharges of pollutants to waters of the United States
containing NMFS Listed Resources of Concern, as defined in Appendix A of the draft 2021
PGP, may seek coverage under the permit by submitting a complete and accurate NOI form that
includes certifying eligibility under one of the five criteria (B-F) in Part 1.1.2.4 of the draft 2021
PGP.

Contents of the NOI

Pursuant to 40 CFR §122.28(b)(2)(ii), the contents of any NOI must be specified in the
general permit and require the submission of information necessary for adequate program
implementation, including at a minimum:

-	the legal name and address of the Owner or Operator,

-	the facility name and address,

-	type of facility or discharges of pollutants,

-	the receiving stream(s), and

-	signed in accordance with §122.22.

The specific requirements of the draft 2021 PGP NOI are identified in the NOI form
provided in Appendix D of the draft 2021 PGP but include those elements identified in the
regulations described above with three additional data elements that are important to fully
characterize the activities for which permit coverage is being provided, namely identification of:

-	pesticide use activities that trigger the PGP requirements to develop a pesticide
discharge management plan and submit an annual report;

-	impaired water(s) and/or Tier 3 water(s) for which permit coverage is being requested
for discharges of pollutants to these waters and demonstration of eligibility for such
discharges; and

-	whether pollutant discharges will be to waters of the United States containing NMFS
Listed Resources of Concern, and, if so, what pest(s) are to be controlled; the pesticide
product(s) to be discharged; the planned quantity and rate of discharge(s) of pollutants;
the number of planned discharges of pollutants; and signed certification by the
Decision-maker that one of the six criteria in Part 1.1.2.4 of the draft 2021 PGP have
been met. EPA recognizes the implementation of pest management measures as
specified in the permit may involve a degree of "adaptive management" such that exact
timing and quantities of applications cannot be determined in advance for the duration
of the permit. EPA expects the Decision-maker to provide the required information to
the extent feasible and consistent with the implementation of the selected pest
management measures.

Also, the draft 2021 PGP requires Decision-makers to submit changes to previous NOI
forms where, for example, coverage for an additional discharge of pollutants not included in the

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original NOI is being requested. EPA expects these NOI change requests to be submitted
primarily in four instances: (1) coverage for a new or expanded pest management area or a new
pesticide use pattern is being requested, (2) discharge to a not-previously identified Tier 3 water
is identified for permit coverage, or (3) discharge to any not-previously identified waters of the
United States containing NMFS Listed Resources of Concern, as defined in Appendix A of the
draft 2021 PGP, is being requested or (4) changes in the treatment area, pesticide product,
method or rate of application, or approximate dates of applications for discharges of pollutants to
waters of the United States containing NMFS Listed Resources of Concern. In cases where this
information was previously provided to the extent feasible and consistent with the
implementation of selected pest management practices, a revised NOI is not required as long as
the discharge continues to be consistent with the information provided in the original NOI
submission. In these four instances, Decision-makers are required to submit revised NOIs that
reflect changes in the areas and types of activities for which coverage is being requested.

1.2.3 Discharge Authorization Date

The 2016 PGP expires at midnight on October 31, 2021. EPA plans to issue this permit
which will become effective on October 31, 2021. For any discharges of pollutants occurring
after the effective date of the final permit and for which Operators are not required to submit an
NOI, Operators will receive permit coverage for those discharges of pollutants under the 2021
PGP. Dischargers who obtained automatic coverage under the 2016 PGP (i.e., Operators who are
not required to submit an NOI) and continue to discharge pollutants after the effective date of the
final permit will receive uninterrupted permit coverage. Decision-makers required to submit
NOIs, as detailed in Part 1.2.2 of the draft 2021 PGP, are authorized consistent with the
timeframes and provisions detailed in Part 1.2.3 of the draft 2021 PGP. Decision-makers who are
required to submit an NOI must begin complying with requirements in Part 2.2 of the draft 2021
PGP as of the effective date of the final permit.

EPA proposes to retain the procedures for NMFS Listed of Resources of Concern that were
included in EPA's 2016 PGP. EPA is currently conducting consultation with the Services for the
reissuance of the permit. Based on the results of consultation with the Services, it may be
necessary to add additional conditions. NOIs are required from Decision-makers according to the
schedule detailed in Table 1-2 in the draft 2021 PGP and as described below:

- Other than for discharges of pollutants in response to a Declared Pest Emergency
Situation or that are to NMFS Listed Resources of Concern, both of which are
described below, Decision-makers who discharge after the effective date of the final
permit will be authorized 10 days after EPA posts on its public Internet website, at
https://www.epa.gov/npdes/pesticide-permitting. receipt of a complete and accurate
NOI unless EPA places a hold on the authorization (i.e., delay authorization). NOIs
submitted electronically will be posted on the NPDES website instantaneously with the
Operator authorized to discharge 10 days after the posting, providing EPA does not
place a hold on the authorization for that NOI. EPA will send automatic confirmation
of receipt of NOIs and of discharge authorization. The Agency may place an
authorization on hold if the Agency determines, including based on information
provided by other interested parties (e.g., US FWS, NMFS), that the Operator may not

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U.S. Environmental Protection Agency	Draft 2021 NPDES Pesticide General Permit Fact Sheet

Note: This document is aprepublication version, signed by all 10 U.S. EPA Regions on December 14, 2020. EPA is
submitting it for publication in the Federal Register. We have taken steps to ensure the accuracy of this version, but
it is not the official version.

be eligible for PGP coverage. See Part 1.1 of the draft 2021 PGP for the eligibility
criteria. Thus, an NOI must be submitted no later than 10 days before the first discharge
for any discharges of pollutants occuring after the effective date of the final permit.

-	Any Decision-maker who discharges pollutants in response to a Declared Pest
Emergency Situation, as defined in Appendix A of the draft 2021 PGP, that is not to
waters of the United States containing NMFS Listed Resources of Concern, for which
that activity triggers the requirement to submit an NOI, is authorized to discharge
pollutants immediately; however, a complete and accurate NOI is required to be
submitted no later than 30 days after beginning to discharge. This delay in NOI
submission and immediate authorization is to allow pest managers the opportunity to
respond to pest emergencies without delay.

-	In any Declared Pest Emergency Situation for discharges of pollutants to waters of the
United States containing NMFS Listed Resources of Concern, the discharges of
pollutants are authorized for at least 60 days or until EPA determines that the
discharges of pollutants may not continue (or places additional conditions on the
discharge) due to concerns related to compliance with the ESA-related conditions of the
draft 2021 PGP. These Decision-makers must file an NOI no later than 15 days after
beginning to discharge pollutants. The NOI must identify:

1.	The location of the pest management area in detail or include a map of the location;

2.	Pest(s) to be controlled;

3.	Pesticide product(s) to be discharged and method of application;

4.	Planned quantity and rate of discharge(s) for each method of application;

5.	Number of planned discharges of pollutants;

6.	Approximate date(s) of planned discharge(s) of pollutants; and

7.	Whether the discharge of pollutants is likely to adversely affect a NMFS Listed
Resource of Concern, including the description of appropriate measures to be
undertaken to avoid or eliminate the likelihood of adverse effects on that identified
NMFS Listed Resource of Concern.

For discharges of pollutants that have already occurred prior to NOI submission, items
1 through 6 above must also be identified in that NOI.

In any Declared Pest Emergency Situation in areas with waters of the United States
containing NMFS Listed Resources of Concern, NMFS will have 30 days after
submission of an NOI (e.g., when EPA posts on the Internet receipt of a complete and
accurate NOI) to provide EPA with a determination as to whether NMFS believes the
eligibility criteria of "not likely to adversely affect listed species or designated critical
habitat" has been met, per Part 1.1.2.4 of the draft 2021 PGP (see also 50 CFR 402.14),
could be met with conditions that NMFS identifies, or has not been met. EPA expects
to rely on NMFS' determination in deciding whether to disallow continued permit
coverage or if additional conditions are necessary to meet the eligibility criteria of "not
likely to adversely affect listed species or designated critical habitat." See Part 1.1.2.4
of the draft 2021 PGP. See also 50 CFR 402.14. If NMFS does not provide EPA with a
recommendation within 30 days of EPA posting on the Internet receipt of a complete

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and accurate NOI, authorization for these discharges of pollutants will continue. If EPA
identifies additional permit conditions, or includes additional permit conditions
recommended by NMFS, as necessary to qualify discharges of pollutants as eligible for
coverage beyond 60 days under the draft 2021 PGP, those conditions remain in effect
for the life of the permit. EPA will advise the Decision-maker within 15 days of
receiving a determination from NMFS whether the discharge of pollutants or discharges
of pollutants qualify for coverage beyond the 60-day authorization provided under the
draft 2021 PGP. If the decision maker does not hear from EPA, the decision maker may
assume that permit authorization continues unless notified otherwise. This approach
provides a reasonable amount of time for Operators to quickly respond to any Declared
Pest Emergency Situation (i.e., 60 days after beginning to discharge pollutants), yet
provides the Agency with an opportunity to ensure that subsequent discharges of
pollutants are controlled as necessary to protect water quality and any NMFS Listed
Resources of Concern.

- For any discharges of pollutants to waters of the United States containing NMFS Listed
Resources of Concern and beginning on or after the effective date of the final permit an
NOI will need to be submitted no later than 30 days before the first discharge occurs.
NOIs submitted electronically will be posted on the NPDES website instantaneously
with the Operator authorized to discharge 30 days after the posting, providing EPA
does not place a hold on the authorization for that NOI. EPA will send automatic
confirmation of receipt of NOIs and of discharge authorization. The additional
timeframe allows NMFS to have sufficient time to review NOI submissions as a result
of discharges of pollutants to waters of the United States containing NMFS Listed
Resources of Concern, as defined in Appendix A of the draft 2021 PGP. EPA may
authorize certain discharges of pollutants in less than 30 days, but no fewer than 10
days, after submission of an NOI for any discharges of pollutants under Criterion B, C,
or E, of Part 1.1.2.4 of the draft 2021 PGP. This is because under criteria B and C,
Operators would have already consulted with NMFS and under criterion E, the
Operator would have received a written letter from NMFS that the discharge of
pollutants will not adversely affect NMFS Listed Resources of Concern. Early
submittal and review of NOIs will help ensure that any issues are addressed and
resolved in a timely manner so that appropriate pesticide applications can proceed as
planned. The Agency may place an authorization on hold if the Agency determines,
including based on information provided by other interested parties and from the
Services' review, that the Operator may not be eligible for PGP coverage. In
determining whether to withhold permit authorization under this permit, EPA expects
to rely on NMFS expertise in making a determination as to whether there is likely to be
adverse effect. Within 30 days after EPA posts on the Internet receipt of a complete and
accurate NOI, for those discharges of pollutants to waters of the United States
containing NMFS Listed Resources of Concern, as defined in Appendix A of the draft
2021 PGP, NMFS will provide EPA with a determination as to whether NMFS has
determined the eligibility criteria of "not likely to adversely affect listed species or
designated critical habitat" has been met, could be met with conditions the NMFS
identifies, or has not been met. EPA expects to rely on NMFS' determination in

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

deciding whether to disallow continued permit coverage or if additional conditions are
necessary. EPA notes that it may be advantageous to the Decision-maker to work with
NMFS prior to submitting the NOI, and to obtain written correspondence from NMFS,
if possible, that pesticide application activities performed consistent with appropriate
measures will avoid or eliminate the likelihood of adverse effects. In this case, as noted
above, EPA may authorize discharges of pollutants in as few as 10 days after the NOI
is submitted, although the operator may not assume authorization before 30 days unless
specifically so notified by EPA.

NOIs submitted electronically will be posted on the NPDES website instantaneously with
the Operator authorized to discharge pollutants 10 or 30 days after the posting, providing EPA
does not place a hold on the authorization for that NOI. EPA will send automatic confirmation of
receipt of NOIs and of discharge authorization.

The draft 2021 PGP contains standard language that provides EPA with the authority to
modify permit terms or terminate permit coverage as appropriate. NMFS and any other interested
persons may provide information to EPA noting any concerns with authorized discharges of
pollutants, including those resulting from Declared Pest Emergency Situations. EPA will
consider that information and take future action as appropriate. As provided in the draft 2021
PGP, in general, EPA may take the following actions:

Part 1.3 - Require Operators to apply for and/or obtain authorization to discharge under
either an NPDES individual permit or an alternative NPDES general permit.

Appendix B, Standard Permit Conditions, 40 CFR 122.41(a) Duty to comply -

Terminate, revoke and reissue, or modify a permit for any permit noncompliance, that is
also grounds for enforcement action.

Part 1.2.3; Part 6.3; Appendix B, Standard Permit Conditions, 40 CFR 122.41(f)
Permit actions - Modify, revoke and reissue, or terminate a permit for cause.

1.2.4 Continuation of this Permit

The draft 2021 PGP specifies procedures for continued coverage under a general permit if
the permit expires prior to a replacement permit being issued. The procedures remain unchanged
from EPA's 2016 PGP. In short, the expired permit would remain in full force and effect in
accordance with the Administrative Procedure Act (5 U.S.C. 558(c)) and EPA's implementing
regulations at 40 CFR 122.6. Any permittee granted coverage prior to the permit's expiration
date will automatically remain covered by the continued permit until the earliest of:

(a) Authorization under a new version of the PGP following timely and accurate submittal
of a complete NOI (if required);

(b) The processing and posting of a Notice of Termination (NOT) consistent with Part
1.2.5.1 of the draft 2021 PGP;

(d) A formal permit decision by EPA not to reissue the general permit, at which time EPA
will identify a reasonable time period for covered dischargers to seek coverage under an

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alternative general permit or an individual permit. Coverage under this permit will
cease when coverage under another permit is granted/authorized; or

(e) EPA has informed the permittee that the permittee's discharges of pollutants are no
longer covered under the permit.

If EPA fails to issue a final general permit prior to the expiration of a previous general
permit the permit will be administratively continued in accordance with section 558(c) of the
Administrative Procedure Act (5 U.S.C. 558(c)) and EPA's implementing regulations at 40 CFR
122.6 and will remain in force and effect for discharges of pollutants that were covered prior to
expiration. However, EPA does not have the authority to provide coverage under an
administratively extended permit to entities not authorized prior to the expiration date of the
permit.

1.2.5 Terminating Coverage

The draft 2021 PGP specifies procedures for terminating coverage under this general
permit. The procedures remain unchanged from EPA's 2016 PGP.

1.2.5.1 Submitting a Notice of Termination

To terminate coverage under the permit, any Decision-maker who submitted a Notice of
Intent to obtain permit coverage is required to submit a Notice of Termination (NOT) in
accordance with information identified in Appendix E of the draft 2021 PGP. The Decision-
maker's authorization to discharge pollutants under the permit terminates at midnight of the day
that a complete NOT is processed and posted on EPA's website

(https://www.epa.gov/npdes/pesticide-permitting). Dischargers automatically covered (as
identified in Part 1.2.3 of the draft 2021 PGP) are automatically terminated upon permanent
cessation of discharge consistent with any of the criteria identified in Part 1.2.5.2 of the draft
2021 PGP.

EPA requires Decision-makers who file a NOT to notify EPA that its obligation to manage
pollutant discharges is no longer necessary for one of the EPA-approved reasons (as described in
Part III. 1.2.5.2 of the fact sheet). If EPA determines that the Decision-maker has not satisfied one
of the conditions in Part 1.2.5.2 of the draft 2021 PGP for being able to submit an NOT (e.g., the
Decision-maker continues to have a discharge of pollutants) then the notice is not valid and the
Decision-maker must continue to comply with the conditions of the draft 2021 PGP. Likewise, if
EPA determines that the NOT is incomplete, the Decision-maker may be found to be in violation
of reporting requirements.

1.2.5.2 When to Submit a Notice of Termination

Once all point source discharges associated with pesticide application have ceased, the
Decision-maker must submit an NOT, as described in Part 1.2.5.1 of the draft 2021 PGP, within
30 days after one or more of the following conditions have been met: (1) a new Decision-maker
has taken over responsibility for the pest control activities; (2) all discharges have ceased from
the application of pesticides for which permit coverage was obtained and discharges of pollutants
are not expected during the remainder of the permit term for any of the use patterns as identified
in Part 1.1.1 of the draft 2021 PGP, or (3) coverage under an individual permit or alternative

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

general permit has been obtained for all discharges of pollutants required to be covered by an
NPDES permit, unless coverage was obtained consistent with Part 1.3 of the draft 2021 PGP, in
which case, coverage under this permit will terminate automatically.

In the draft 2021 PGP, EPA is requiring an NOT from Operators who on their own switch
to a different permit to provide the Agency with clear notice that the Operator's discharge of
pollutants is not covered under two NPDES permits. Operators who terminate coverage based on
an EPA request consistent with Part 1.3 of the draft 2021 PGP are not required to submit an
NOT.

1.2.5.3 Termination for Operators not Required to Submit an NOI

Operators covered under the draft 2021 PGP who are not required to submit an NOI are
terminated from permit coverage when there is no longer a discharge from the application of
pesticides, or the discharges of pollutants are covered under an NPDES individual permit or
alternative NPDES general permit. Operators not required to submit an NOI are also not required
to submit an NOT.

1.3 Alternative Permits

The draft 2021 PGP specifies requirements and procedures for coverage under an
alternative permit. The requirements and procedures remain unchanged from EPA's 2016 PGP.

1.3.1 Requirements for Coverage Under an Alternative Permit

EPA may require an individual permit (in accordance with 40 CFR 122.28(b)(3)(ii)) or
coverage under an alternative NPDES general permit instead of the draft 2021 PGP (when
finalized). The regulations also provide that any interested party may petition EPA to take such
an action. The issuance of the individual permit or alternative NPDES general permit is in
accordance with 40 CFR part 124 and provides for public comment and appeal of any final
permit decision. The circumstances in which such an action would be taken are set forth at 40
CFR 122.28(b)(3). EPA notes that discharges of pollutants from anti-foulant hull coatings,
biofouling prevention, and residuals from ballast water treatment technologies are already
covered under the NPDES Vessels General Permit requirements and do not require coverage
under this general permit (see EPA NPDES Vessels General Permit at
https://www.epa.gov/npdes/vessels).

1.3.2 Operator Requesting Coverage under an Alternative Permit

After receiving permit coverage under the draft 2021 PGP (when issued), the Operator may
request to be excluded from such coverage by applying for an individual permit or alternative
NPDES general permit. In this case, the Operator must submit an individual permit application in
accordance with 40 CFR 122.28(b)(3)(iii), along with a statement of reasons supporting the
request, to EPA at the applicable EPA Regional Office listed in Part 8.2 of the draft 2021 PGP.
The request may be granted by issuance of an individual permit or authorization of coverage
under an alternative general permit if the reasons are adequate to support the request. Under this
scenario, if an individual permit is issued, or authorization to discharge pollutants under an
alternative general permit is granted, coverage under this permit is automatically terminated

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

under 40 CFR 122.28(b)(3)(iv) on the effective date of the individual permit or the date of
authorization of coverage under the alternative general permit.

Part 1.3.2 of the draft 2021 PGP explains an Operators ability to apply for coverage under
an individual permit in lieu of coverage under this general permit and describes the steps to take
to be excluded from this permit after being authorized under this permit. Cases where an
individual NPDES permit may be required are described fully in 40 CFR 122.28(b)(3)(iii). The
following are the pertinent situations for this permit where an individual permit may be
necessary:

a) A Water Quality Management plan containing requirements applicable to such point
sources is approved;

b) Circumstances have changed since the time of the request to be covered so that the
discharger is no longer appropriately controlled under the general permit, or either a
temporary or permanent reduction or elimination of the authorized discharge is
necessary; or

c) The discharge(s) is a significant contributor of pollutants. In making this determination,
EPA may consider the following factors:

(1) The location of the discharge of pollutants with respect to waters of the United
States;

(2) The size of the discharge of pollutants;

(3) The quantity and nature of the pollutants discharged to waters of the United States;
and

(4) Other relevant factors.

EPA may require an Operator to apply for an individual permit only if EPA notifies the
Operator in writing that a permit application for an individual permit is required. See 40 CFR
124.52. This notice must include a brief statement of the reasons for this decision, an application
form, a statement setting a time for the Operator to file the application, information on appeals
rights, and a statement that on the effective date of the individual NPDES permit the general
permit as it applies to the individual Operator shall automatically terminate. EPA may grant
additional time upon request of the applicant.

When an individual NPDES permit is issued to an Operator otherwise subject to a general
NPDES permit, the applicability of the general permit to the individual NPDES Operator is
automatically terminated on the effective date of the individual permit.

Note that an individual permit is required for discharges from the application of pesticides
to waters where such waters are impaired by a substance which either is an active ingredient in
that pesticide or is a degradate of such an active ingredient, and for certain applications of
pesticides to Tier 3 waters where such applications are not made to restore or maintain water
quality or to protect public health or the environment in such a way that they either do not
degrade water quality or only degrade water quality on a short-term or temporary basis. In these
cases, authorization under this general permit would not have been available in the first place.

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

1.4 Severability

Invalidation of a portion of this permit (when issued) does not necessarily render the whole
permit invalid. If any provisions of this permit are reviewed and vacated by a court, only those
provisions vacated will be deemed invalidated by EPA. The remainder of the permit conditions
will remain in effect. EPA will evaluate the effect of such invalidation on a case-by-case basis.

1.5 Other Federal and State Laws

Part 1.5 of the draft 2021 PGP includes the following language: "Operators must comply
with all other applicable federal and state laws and regulations that pertain to the application of
pesticides. For example, this permit does not negate the requirements under the FIFRA and its
implementing regulations to use registered pesticides consistent with the product's labeling. In
fact, applications in violation of certain FIFRA requirements could also be a violation of the
permit and therefore a violation of the CWA (e.g. exceeding label application rates).

Additionally, other laws and regulations might apply to certain activities that are also covered
under this permit (e.g., United States Coast Guard regulations)."

This part of the draft 2021 PGP is intended to clarify that Operators are still required to
comply with other applicable laws, and that merely complying with the conditions of this permit
may not result in compliance with all other applicable regulations. In fact, compliance with
certain permit terms expressly requires Operators to comply with other laws to demonstrate
compliance with this permit. For example, the draft 2021 PGP requires Operators to use "Pest
Management Measures" to "minimize" discharges of pollutants. As these terms are defined in
Appendix A of the draft 2021 PGP, Operators must use practices that comply with, among other
things, "relevant legal requirements" to reduce and/or eliminate pollutant discharges to waters of
the United States.

1.6 Federally Listed Endangered and Threatened Species and Designated Critical
Habitat.

Part 1.6 of the draft 2021 PGP clarifies that Operators are required to comply with
conditions and/or requirements for discharges of pollutants to waters of the United States from
any ESA Section 7 consultation or ESA Section 10 permit for pesticides application activities
covered under this permit.

2. Effluent Limitations

Background

The CWA requires that all point source discharges of pollutants from existing facilities, or
in this case, pesticide applications, meet technology-based effluent limitations4 (TBELs)

4 Natural Res. Def. Council, Inc. v. EPA, 673 F.2d 400, 403 (D.C. Cir. 1982) (noting that "section 502(11)
defines 'effluent limitation' as 'any restriction' on the amounts of pollutants discharged, not just a numerical
restriction"; holding that section of CWA authorizing courts of appeals to review promulgation of "any effluent
limitation or other limitation" did not confine the court's review to the EPA's establishment of numerical limitations

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U.S. Environmental Protection Agency	Draft 2021 NPDES Pesticide General Permit Fact Sheet

Note: This document is aprepublication version, signed by all 10 U.S. EPA Regions on December 14, 2020. EPA is
submitting it for publication in the Federal Register. We have taken steps to ensure the accuracy of this version, but
it is not the official version.

representing the applicable levels of control. 33 U.S.C. 1311(b)(l)(A)(BPT), (b)(2)(A)(BAT),
(b)(2)(E)(BCT). Additionally, water quality-based effluent limitations (WQBELs) are required
where the technology-based effluent limitations are not sufficient to protect applicable water
quality standards. 33 U.S.C. 1311(b)(1)(C). Water quality-based requirements will be discussed
in greater depth in Part III.3 of the fact sheet. The technology-based effluent limitations
contained in the draft 2021 PGP are non-numeric and constitute the levels of control that reduce
the area and duration of the discharge of pollutants to waters of the United States.

The Clean Water Act Requires EPA to Develop Effluent Limitations that Represent the
Following:

Best Practicable Control Technology Currently Available (BPT)

The CWA requires BPT effluent limitations for conventional, toxic, and non-conventional
pollutants. Section 304(a)(4) designates the following as conventional pollutants: biochemical
oxygen demand (BOD), total suspended solids, fecal coliform, pH, and any additional pollutants
defined by the Administrator as conventional. The Administrator designated oil and grease as an
additional conventional pollutant on July 30, 1979. 40 CFR 401.16. EPA has identified 65
pollutants and classes of pollutants as toxic pollutants, of which 126 specific substances have
been designated priority toxic pollutants. 40 CFR 401.15 and 40 CFR Part 423 Appendix A. All
other pollutants are considered to be non-conventional.

In specifying BPT, under CWA section 301(b)(1)(A); 304(b)(1)(B); 40 CFR 125.3(d)(1),
EPA evaluates a number of factors. EPA first considers the total cost of applying the control
technology in relation to the effluent reduction benefits. The Agency also considers the age of
the equipment and facilities, the processes employed, and any required process changes,
engineering aspects of the control technologies, non-water quality environmental impacts
(including energy requirements), and such other factors as the EPA Administrator deems
appropriate. Traditionally, EPA establishes BPT effluent limitations based on the average of the
best performance of facilities within the industry of various ages, sizes, processes, or other
common characteristics. Where existing performance is uniformly inadequate, BPT may reflect
higher levels of control than currently in place in an industrial category if the Agency determines
that the technology can be practically applied.

Best Conventional Pollutant Control Technology (BCT)

The 1977 amendments to the CWA required EPA to identify effluent reduction levels for
conventional pollutants associated with BCT for discharges from existing industrial point
sources. CWA section 301(b)(2)(E); 304(b)(4)(B); 40 CFR 125.3(d)(2). In addition to
considering the other factors specified in section 304(b)(4)(B) to establish BCT limitations, EPA

on pollutant discharges, but instead authorized review of other limitations under the definition) (emphasis added). In
Natural Res. Def. Council, Inc. v. Costle, 568 F.2d 1369 (D.C. Cir. 1977), the D.C. Circuit stressed that when
numerical effluent limitations are infeasible, EPA may issue permits with conditions designed to reduce the level of
effluent discharges of pollutants to acceptable levels.

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U.S. Environmental Protection Agency	Draft 2021 NPDES Pesticide General Permit Fact Sheet

Note: This document is aprepublication version, signed by all 10 U.S. EPA Regions on December 14, 2020. EPA is
submitting it for publication in the Federal Register. We have taken steps to ensure the accuracy of this version, but
it is not the official version.

also considers a two part "cost-reasonableness" test. EPA explained its methodology for the
development of BCT limitations in 1986. 51 FR 24974 (July 9, 1986).

Best Available Technology Economically Achievable (BAT)

For toxic pollutants and non-conventional pollutants, EPA includes technology-based
effluent limitations based on BAT in NPDES permits. CWA section 301(b)(2)(A); 304(b)(2)(B);
40 CFR 125.3(d)(3). In establishing BAT, the technology must be technologically "available"
and "economically achievable." The factors considered in assessing BAT include the cost of
achieving BAT effluent reductions, the age of equipment and facilities involved, the process
employed, potential process changes, non-water quality environmental impacts, including energy
requirements and other such factors as the EPA Administrator deems appropriate. The Agency
retains considerable discretion in assigning the weight accorded to these factors. BAT limitations
may be based on effluent reductions attainable through changes in an Operator's processes and
operations. Where existing performance is uniformly inadequate, BAT may reflect a higher level
of performance than is currently being achieved within a particular subcategory based on
technology transferred from a different subcategory or category. BAT may be based upon
process changes or internal controls, even when these technologies are not common industry
practice.

The draft 2021 PGP contains effluent limitations that correspond to required levels of
technology-based control (BPT, BCT, BAT) for discharges of pollutants under the CWA. Some
effluent limitations have been established by examining other existing laws, requirements and
practices. Because these are demonstrated practices, EPA has found that they are technologically
available and economically practicable (BPT) or achievable (BAT).

Technology-Based Effluent Limitations

Technology-based effluent limitations are in many cases established by EPA in regulations
known as effluent limitations guidelines, or "ELGs." EPA establishes these regulations for
specific industry categories or subcategories after conducting an in-depth analysis of that
industry. The CWA sets forth different standards for the ELGs based upon the type of pollutant
or the type of permittee involved. Where EPA has not issued effluent guidelines for an industry,
EPA and State permitting authorities establish effluent limitations for NPDES permits on a case-
by-case basis based on their best professional judgment. See 33 U.S.C. § 1342(a)(1); 40 C.F.R. §
125.3(cY2Y

As stated above, the CWA establishes two levels of technology-based controls. The first
level of control, "best practicable control technology currently available," or "BPT" applies to all
pollutants. CWA section 304(b)(1)(B); 33 U.S.C. 1314(b)(1)(B). BPT represents the initial stage
of pollutant discharge reduction, designed to bring all sources in an industrial category up to the
level of the average of the best source in that category. See EPA v. National Crushed Stone
Association, 449 U.S. 64, 75-76 (1980). In the second level of control, all point sources are
required to meet effluent limitations based on "best conventional pollutant control technology,"
or "BCT" CWA section 304(b)(4)(B); 33 U.S.C. 1314(b)(4)(B) or "best available technology
economically achievable," or "BAT" CWA section 301(b)(2)(A); 33 U.S.C. 1311(b)(2)(A),
depending on the types of pollutants discharged. BCT applies to conventional pollutants, listed at

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U.S. Environmental Protection Agency	Draft 2021 NPDES Pesticide General Permit Fact Sheet

Note: This document is aprepublication version, signed by all 10 U.S. EPA Regions on December 14, 2020. EPA is
submitting it for publication in the Federal Register. We have taken steps to ensure the accuracy of this version, but
it is not the official version.

40 CFR 401.16 (biological oxygen demand (BOD), pH, fecal coliform, TSS, and oil and grease).
BAT applies to toxic and non-conventional pollutants. Technology-based limitations are to be
applied throughout industry without regard to receiving water quality. Appalachian Power Co. v.
EPA, 671 F.2d 801 (4th Cir. 1982).

EPA's Authority to Include Non-Numeric Technology-Based Limitations in this Permit

All NPDES permits are required to contain technology-based effluent limitations. 40 CFR
§§ 122.44(a)(1) and 125.3. CWA sections 301(b)(1)(A) for (BPT); 301(b)(2)(A) for (BAT); and
301(b)(2)(E) for (BCT). Technology-based effluent limitations in the draft 2021 PGP represent
the BPT (for conventional, toxic, and non-conventional pollutants), BCT (for conventional
pollutants), and BAT (for toxic pollutants and non-conventional) levels of control for the
applicable pollutants. When EPA has not promulgated effluent limitation guidelines for an
industry, or if an Operator is discharging a pollutant not considered in the development of the
effluent guideline, permit limitations are based on the best professional judgment (BPJ,
sometimes also referred to as "best engineering judgment") of the permit writer. 33 U.S.C.
§ 1342(a)(1); 40 CFR 125.3(c). See Student Public Interest Group v. Fritzsche, Dodge & Olcott,
759 F.2d 1131, 1134 (3rd Cir. 1985); American Petroleum Inst. v. EPA, 787 F.2d 965, 971 (5th
Cir. 1986). For the draft 2021 PGP, the technology-based effluent limitations are based on BPJ
decision-making because no ELG applies.

Under EPA's regulations, non-numeric effluent limitations are authorized in lieu of
numeric limitations, where "[njumeric effluent limitations are infeasible." 40 CFR 122.44(k)(3).
As far back as 1977, courts have recognized that there are circumstances when numeric effluent
limitations are infeasible and have held that EPA may issue permits with conditions (e.g.,
narrative effluent limitations or best management practices) designed to reduce the level of
effluent discharges to acceptable levels. Natural Res. Def. Council, Inc. v. Costle, 568 F.2d 1369,
1380 (D.C.Cir. 1977).

Through the Agency's NPDES permit regulations, EPA interpreted the CWA to allow best
management practices (BMPs) to take the place of numeric effluent limitations under certain
circumstances. Federal regulations at 40 CFR §122.44(k), entitled "Establishing limitations,
standards, and other permit conditions (applicable to state NPDES programs ...)," provides that
permits may include BMPs to control or abate the discharge of pollutants when: (1) "[authorized
under section 402(p) of the CWA for the control of stormwater discharges"; or (2) "[njumeric
effluent limitations are infeasible." 40 CFR § 122.44(k).

Courts have held that the CWA does not require EPA to set numeric limitations where such
limits are infeasible. Citizens Coal Council v. EPA, 447 F.3d 879, 895-96 (6th Cir. 2006). The
Sixth Circuit cited Water keeper Alliance, Inc. v. EPA, 399 F.3d 486, 502 (2nd Cir. 2005), stating
"site-specific BMPs are effluent limitations under the CWA." Additionally, the Sixth Circuit
cited Natural Res. Def. Council, Inc. v. EPA, 673 F.2d 400, 403 (D.C.Cir.1982) noting that

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"section 502(11) [of the CWA] defines 'effluent limitation' as 'any restriction' on the amounts of
pollutants discharged, not just a numerical restriction."5

For the draft 2021 PGP, EPA is using the term "Pest Management Measures," as defined in
Appendix A of the draft 2021 PGP, to represent those practices used to meet the non-numeric
effluent limitations.

EPA's Decision to Include Non-Numeric Technology-Based Effluent Limitations in the
Draft 2021 PGP and Rationale for Why the Limits Represent the Appropriate (BPT, BCT,
or BAT) Level of Control.

As described above, numeric effluent limitations are not always feasible because the
discharges of pollutants pose challenges not presented by other types of NPDES-regulated
discharges of pollutants. The technology-based effluent limitations remain unchanged from
EPA's 2016 PGP. The technology-based effluent limitations in this permit are non-numeric
based on the following facts:

- The point in time for which a numeric effluent limitation would apply is not easily
determinable. For discharges of pollutants from the application of pesticides, the
discharges of pollutants can be highly intermittent with those discharges of pollutants
not practically separable from the pesticide application itself. For example, the
discharge from the application of a chemical pesticide to waters of the United States is
a discharge of pollutants when there is a residual remaining in the ambient water after
the pesticide is no longer serving its intended purpose {i.e., acting as a pesticide against
targeted pests in the applied medium). This discharge of pollutants also will have
combined with any other discharges of pollutants to that waterbody (be it from other
point sources, non-point source runoff, air deposition, etc.). Given this situation, it is
not clear what would be measured for a numeric limit or when.

- For discharges from the application of pesticides, there are often many short durations,
highly variable, pollutant discharges to surface waters from many different locations for
which it would be difficult to establish a numeric limitation at each location. This
variability makes setting reasonable and fair numeric effluent limitations for pesticide
applications extremely difficult. Even in a normal plant specific setting, EPA takes into
account the variability of pollutant removal performance at a facility operated in
compliance with applicable statutory and regulatory requirements to derive technology-
based limitations. In the water-quality based effluent limitations context, EPA takes
into account ambient conditions of the waterbody which can require complex
modelling and formulas to derive what discharge of pollutant level is necessary,
without being overly stringent, to protect water quality. In the context of pesticide
application, the numbers of variables that would affect such a calculation becomes
unworkable. In this situation, requiring the use of standard control practices {i.e.,

5 See also; Northwest Envtl. Advocates v. City of Portland, 56 F.3d 979, 988 (9th Cir. 1995) (finding that a
narrative effluent limitation was an enforceable condition of an NPDES permit).

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

narrative non-numeric effluent limitations), provides a reasonable approach to control
pesticide discharges of pollutants.

- The precise location for which a numeric effluent limitation would apply is not clear.
Discharges from the application of pesticides are different from discharges of pollutants
of process wastewater from a particular industrial or commercial facility where the
effluent is more predictable and easily identified as an effluent from a conveyance (e.g.,
pipe or ditch), can be precisely measured for compliance prior to discharge, and can be
more effectively analyzed to develop numeric effluent limitations.

- EPA does not have sufficient information to develop numeric effluent limitations at this
time. To develop numeric technology-based effluent limitations, EPA must evaluate
factors outlined in 40 CFR 125.3, such as the age of equipment and facilities involved,
the process employed, the potential process changes, and non-water quality
environmental impacts. In addition, EPA estimates that more than 400 pesticide active
ingredients contained in over 3,500 pesticide products may be covered under this
permit.

In the context of this general permit, EPA has determined these non-numeric effluent limits
represent the best practicable technology (BPT) for all pollutants, the best conventional pollutant
control technology for conventional pollutants (BCT) and the best available technology
economically achievable (BAT) for toxic and non-conventional pollutants. EPA has determined
that the combination of pollution reduction practices described below are the most
environmentally sound way to control the point source discharges of biological pesticides, and
chemical pesticides that leave a residue.

Technology-based effluent limitations in this permit are presented specific to each pesticide
use pattern to reflect the variations in procedures and expectations for the use and application of
pesticides. These non-numeric effluent limitations are expected to reduce the point source
discharges of pollutants to waters of the United States, thereby protecting the receiving waters,
including to the extent necessary to meet applicable water quality standards. EPA notes that the
draft 2021 PGP uses the term "Pest Management Measures." Use of the term Pest Management
Measures is intended to better describe the range of pollutant reduction practices that may be
employed when applying pesticides, whether they are structural, non-structural or procedural and
includes BMPs as one of the components.

The BAT/BPT/BCT effluent limitations in this permit are expressed as specific pollution
prevention requirements for minimizing the pollutant levels in the discharge. In the context of
this general permit, these requirements represent the best technologically available and
economically practicable and achievable controls. EPA has determined that the combination of
pollution prevention approaches and structural management practices required by these limits are
the most environmentally sound way to control the discharge of pollutants to meet the effluent
limitations. Pollution prevention continues to be the cornerstone of the NPDES program.

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

Requirements are technologically available

EPA has found that the requirements of this permit represent the appropriate level of
control representing BPT, BCT, and BAT. The draft 2021 PGP requires certain Operators to
implement Pest Management Measures to meet the technology-based effluent limitations that are
based on IPM principles. See further discussion of pest management measures below. Unlike
other general permits, the technology available to Operators depends on the type of Operator
(e.g. Applicator v. Decision-maker). For this reason, technology-based effluent limitations vary
depending on Operator type. As an example of an effluent limit that meets BPT and BAT
standards, applicators are required to maintain pesticide application equipment in proper
operating condition, including requirement to calibrate, clean, and repair such equipment and
prevent leaks, spills, or other unintended discharges. This effluent limitation is not appropriate
for decision-makers that do not apply the pesticide themselves and as such, is not an effluent
limitation for decision-makers. EPA determined that calibrating, cleaning, and repairing
pesticide application equipment is technologically available and based on EPA's evaluation of
this industry, is currently being implemented by many operators and is a practice that every
operator should be doing when using pesticides, as a way to prevent leaks, spills, and other
unintended discharges, such as over-applying pesticides as a result of poorly maintained
equipment.

Requirements meet the BPT and BAT economic tests set forth in the CWA

There are different economic considerations under BPT, BCT, and BAT. EPA finds that
the limits in the draft 2021 PGP meet the BPT and BAT economic tests. Because the types of
controls under consideration minimize toxic, nonconventional, and conventional pollutants,
conventional pollutants are controlled by the same practices that control toxic and
nonconventional pollutants. Hence, EPA is evaluating effluent limits using a BPT and a BAT
standard, but since conventional pollutants will also be adequately controlled by these same
effluent limits for which EPA applied the BPT and BAT tests, EPA has determined that it is not
necessary to conduct BCT economic tests.

Under BPT, EPA has determined that the requirements of this draft 2021 PGP are
economically practicable since they contain the same requirements as found in the 2011 PGP and
the 2016 PGP. To make the original BPT determination, EPA considered the reasonableness of
the relationship between the costs of application of technology in relation to the effluent
reduction benefit derived. CWA section 301(b)(1)(B); 40 CFR 125.3(d)(1). This analysis was
documented in the fact sheet accompanying the 2011 PGP (available at
https://downloads.regulations.gov/EPA-HQ-OW-2010-0257-1276/content.pdf). EPA estimates
that the proposed 2021 PGP will cover approximately 14,300 Operators. In light of the original
BPT determination and the fact that the draft 2021 PGP does not alter per entity compliance
costs, EPA finds that the BPT limits have a cost that is justified by the effluent reduction
resulting from the BPT effluent limitations and that for BAT, the costs are economically
achievable because they can reasonably be borne by the industry as a whole.

EPA continues to study the efficacy of various types of pollution prevention measures and
BMPs; however, for this permit numeric limitations are still not feasible.

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

Requirements have acceptable non-water quality environmental impacts.

EPA finds that the controls in the permit have acceptable non-water quality environmental
impacts. Because the draft 2021 PGP contains the same requirements as the 2016 PGP there are
no significant changes to the non-water quality environmental impacts. EPA also notes that the
requirement to comply with the FIFRA label incorporates the consideration of the environmental
impacts of the pesticide's use with the benefits of the pesticide's use. When EPA determines that
a pesticide product can be registered for use, the Agency has concluded that the use of the
pesticide product will not cause unreasonable adverse effects to humans or the environment
when applied according to the label directions and restrictions. "Unreasonable adverse effects"
takes into account the economic, social, and environmental costs and benefits of the use of the
pesticide. EPA finds that the pollutant discharges authorized by this permit have recreational,
environmental or other human benefits. For example, permittees will discharge pollutants to
control for mosquitos and other flying insects in order to prevent the spread of infectious
diseases, such as malaria, vesicular stomatitis, and West Nile Virus. Control of weed, algae, and
plant pathogens promotes healthy aquatic communities and recreational and other benefits for the
human population. Permittees will also discharge pollutants to control invasive and nuisance
aquatic animals, such as fish, lampreys, and mollusks, which negatively affect aquatic
biodiversity, human health, and economic stability. Pollutant discharges will also control pests
that threaten the health of the forest canopy, such as the gypsy moth. This permit includes permit
terms which provide reasonable protection to impacted waters of the United States without
constraining the use of these pesticides which provide acceptable non-water quality
environmental impacts.

Pest Management Measures Used to Meet the Technology-Based Effluent Limitations

Just as there is variability in the pesticide applications as described above, there is
variability in the Pest Management Measures that can be used to meet the effluent limitations.
Therefore, EPA is not mandating the specific Pest Management Measures Operators must
implement to meet the limitations. This is analogous to an industrial situation where discharges
of pollutants to waters of the United States are via pipes and a numeric effluent limitation may be
specified as a given quantity of pollutant that may be discharged, but EPA would not specify
what technology should be employed to meet that limitation. For pesticides, namely
mosquitocides, for example, Part 2.2.1.b of the draft 2021 PGP requires mosquito control
Decision-makers to consider mechanical/physical methods of control to eliminate or reduce
mosquito habitat. How this is achieved will vary by Operator: For some, this may be achieved
through elimination of development habitat (e.g. filling low areas, dredging, etc.) while for
others these measures will not be feasible. Thus, a given Pest Management Measure may be
acceptable and appropriate in some circumstances but not in others. In this respect, the non-
numeric effluent limitations in the draft 2021 PGP are similar to performance-based numeric
effluent limitations, which also do not require specific control technologies as long as the
limitations are met.

Pest Management Measures can be actions (including processes, procedures, schedules of
activities, prohibitions on practices, and other management practices), or structural or installed
devices to prevent or reduce water pollution. The key is determining what measure is appropriate

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

for the situation in order to meet the effluent limitation. In this permit, Operators are required to
implement site-specific Pest Management Measures to meet these effluent limitations. The
permit along with this fact sheet provide examples of Pest Management Measures, but Operators
must tailor these to their situations as well as improve upon them as necessary to meet the
effluent limitations.

The approach to Pest Management Measures in this permit is consistent with the CWA as
well as its implementing regulations at 40 CFR 122.44(k)(4). Section 402(a)(2) of the CWA
states: "The administrator shall prescribe conditions for such permits to assure compliance with
the requirements in paragraph (1) . . . including conditions on data and information collection,
reporting and such other requirements as he deems appropriate." (Section 402(a)(1) includes
effluent limitation requirements.) This statutory provision is reflected in the CWA implementing
regulations, which state that BMPs (in this case, specifically Pest Management Measures) can be
included in permits when, "[t]he practices are reasonably necessary to achieve effluent
limitations and standards or to carry out the purposes and intent of the CWA." 40 CFR
122.44(k)(4).

Implementation of Pest Management Measures

Part 2.0 of the draft 2021 PGP requires Operators to implement Pest Management
Measures to meet the technology-based effluent limitations listed in that Part. It also provides
Operators with important considerations for the implementation of their specific Pest
Management Measures. Some Decision-makers will have to document how such factors were
taken into account in the implementation of their Pest Management Measures (See Part 5 of the
draft 2021 PGP). EPA recognizes that not all of these considerations will be applicable to every
pest management area nor will they always affect the choice of Pest Management Measures.
EPA expects that Operators have the experience and working knowledge to apply pesticides
properly. The draft 2021 PGP requires the Operator to apply such expertise and working
knowledge to use best professional judgment in meeting the permit terms. If Operators find their
Pest Management Measures are not minimizing discharges of pollutants adequately, the Pest
Management Measures must be modified as expeditiously as practicable. See Part 6 of the draft
2021 PGP, Corrective Action.

EPA recognizes that Operators need the flexibility to tailor Pest Management Measures to
their situation as well as improve upon them as necessary to meet the technology-based effluent
limitations. Decision-makers will tailor Pest Management Measures based on available
information and the best professional judgment of qualified personnel. For example, while Part
2.2 of the draft 2021 PGP requires Decision-makers to evaluate other means than pesticide use,
the Decision-makers ultimately decide what ultimate pest control method is employed. Thus,
while mechanical pest removal or less toxic chemicals may be possible options, the Decision-
maker is in the best position to know what method is most appropriate and effective against the
target pest.

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U.S. Environmental Protection Agency	Draft 2021 NPDES Pesticide General Permit Fact Sheet

Note: This document is aprepublication version, signed by all 10 U.S. EPA Regions on December 14, 2020. EPA is
submitting it for publication in the Federal Register. We have taken steps to ensure the accuracy of this version, but
it is not the official version.

Pest Management Measures and Technology-Based Effluent Limitations - Definition of
"Minimize"

EPA has found that the requirements of the draft 2021 PGP represent the appropriate BPT,
BCT and BAT level of control. The non-numeric effluent limitations require Operators to
"minimize" discharges of pollutants. Consistent with the control level requirements of the CWA,
the term "minimize" means to reduce and/or eliminate pollutants discharges to waters of the
United States through the use of Pest Management Measures to the extent technologically
available and economically achievable and practicable. For many pesticide applications,
minimization of the discharge of pesticides to waters of the United States can be achieved
without using highly engineered, complex pest control systems. The specific limits included in
Part 2.0 of the draft 2021 PGP emphasize effective "low-tech" approaches, including using only
the amount of pesticide product and frequency of pesticide application necessary to control the
target pest, performing equipment maintenance and calibration, assessing weather conditions
prior to pesticide application, accurately identifying the pest problem, efficiently and effectively
managing the pest problem, and properly using pesticides.

Statutes, Regulations, and Other Requirements

In addition to the applicable permit requirements, Operators must comply with all applicable
statutes, regulations and other requirements including, but not limited to, requirements contained
in the labeling of pesticide products approved under FIFRA ("FIFRA labeling"). See Part 1.5 of
the draft 2021 PGP. See also Part 2.0 ("As stated in Part 1.5, this permit requires all Operators to
comply with all other applicable federal or state laws and regulations that pertain to application
of pesticides by the Operator."). Although the FIFRA label and labeling requirements are not
effluent limitations, it is illegal to use a registered pesticide inconsistent with its labeling. In fact,
Operators discharging under EPA's PGP must comply with FIFRA labeling requirements in
order to be in compliance with the PGP technology-based effluent limits. Per parts 2.1 and 2.2 of
the draft 2021 PGP, "To meet the effluent limitations of this permit, all Applicators [or Decision-
makers] must implement Part 2.1 [or Part 2.2] to minimize the discharge of pesticides to waters
of the United States from the application of pesticides, through the use of Pest Management
Measures, as defined in Appendix A." Per Appendix A, Pest Management Measure means "any
practice used to meet the effluent limitations that comply with manufacturer specifications,
industry standards and recommended industry practices related to the application of pesticides,
relevant legal requirements and other provisions that a prudent Operator would implement to
reduce and/or eliminate pesticide discharges to waters of the United States." Pest Management
Measures include FIFRA labeling requirements. Therefore, if Operators apply a pesticide in a
manner inconsistent with any relevant water-quality related FIFRA labeling requirements such as
those relating to application sites, rates, frequency, and methods, as well as provisions
concerning proper storage and disposal of pesticide wastes and containers, the Operators would
be in violation of the effluent limitation to minimize pesticides entering the waters of the United
States. For example, an Operator, who is a pesticide Applicator, decides to use a mosquito
adulticide pesticide product with a FIFRA label that contains the following language, "Apply this
product at a rate not to exceed one pound per acre." The Applicator applies this product at higher
than the allowable rate, which results in excess product being discharged into waters of the
United States. EPA would find that this application was a misuse of the pesticide under the

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

FIFRA label. Because of the misuse the Agency might also determine that the effluent limitation
that requires the Operator to minimize discharges of pollutants to waters of the United States was
violated, depending on the specific facts and circumstances. Therefore, pesticide use inconsistent
with certain FIFRA labeling requirements could result in the Operator being held liable for a
CWA violation as well as a FIFRA violation.

Technology-Based Effluent Limitations in the PGP

In the draft 2021 PGP, all Operators are classified as either "Applicators" or "Decision-
makers" or both. An Applicator is an entity who performs the application of a pesticide or who
has day-to-day control of the application (i.e., they are authorized to direct workers to carry out
those activities) that results in a discharge to waters of the United States. A Decision-maker is an
entity with control over the decision to perform pesticide applications, including the ability to
modify those decisions that result in discharges of pollutants to waters of the United States. As
such, more than one Operator may be responsible for compliance with this permit for any single
discharge from the application of pesticides. EPA has delineated the non-numeric effluent
limitations into tasks that EPA expects the Applicator to perform and tasks that EPA expects the
Decision-maker to perform. In doing so, EPA has assigned the Applicator and the Decision-
maker different responsibilities.

2.1 Applicators' Responsibilities

Part 2.1 of the draft 2021 PGP contains the general technology-based effluent limitations
that all Applicators must perform, regardless of pesticide use pattern. These effluent limitations
are generally preventative in nature and are designed to minimize pesticide discharges into
waters of the United States. All Applicators are required to minimize the discharge of pesticides
to waters of the United States by doing the following:

2.1.1 To the extent not determined by the Decision-maker, use only the amount of
pesticide and frequency of pesticide application necessary to control the target
pest, using equipment and application procedures appropriate for this task.

As noted earlier, it is illegal to use a pesticide in any way prohibited by the FIFRA
labeling. Also, use of pesticides must be consistent with any other applicable state or federal
laws. To minimize the total amount of pesticide discharged, Operators must use only the amount
of pesticide and frequency of pesticide application necessary to control the target pest. Using
only the amount of pesticide and frequency of pesticide application needed ensures maximum
efficiency in pest control with the minimum quantity of pesticide. Using only the amount and
frequency of applications necessary can result in cost and time savings to the user. To minimize
discharges of pollutants, Operators should base the rate and frequency of application on what is
known to be effective against the target pest.

2.1.2 Maintain pesticide application equipment in proper operating condition, including
requirement to calibrate, clean, and repair such equipment and prevent leaks,
spills, or other unintended discharges.

Common-sense and good housekeeping practices enable pesticide users to save time and
money and reduce the potential for unintended discharge of pesticides to waters of the United

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

States. Regular maintenance activities should be practiced and improper pesticide mixing, and
equipment loading should be avoided. When preparing the pesticides for application be certain
that you are mixing them correctly and preparing only the amount of material that you need.
Carefully choose the pesticide mixing and loading area and avoid places where a spill will
discharge into waters of the United States. Some basic practices Operators should consider are:

- Inspect pesticide containers at purchase to ensure proper containment;

- Maintain clean storage facilities for pesticides;

- Regularly monitor containers for leaks;

- Rotate pesticide supplies to prevent leaks that may result from long term storage; and

- Promptly deal with spills following manufacturer recommendations.

To minimize discharges of pollutants, Applicators must ensure that the rate of application
is calibrated (i.e. nozzle choice, droplet size, etc.) to deliver the appropriate quantity of pesticide
needed to achieve greatest efficacy against the target pest. Improperly calibrated pesticide
equipment may cause either too little or too much pesticide to be applied. This lack of precision
can result in excess pesticide being available or result in ineffective pest control. When done
properly, equipment calibration can assure uniform application to the desired target and result in
higher efficiency in terms of pest control and cost. It is important for Applicators to know that
pesticide application efficiency and precision can be adversely affected by a variety of
mechanical problems that can be addressed through regular calibration. Sound maintenance
practices to consider are:

- Choosing the right spray equipment for the application

- Ensuring proper regulation of pressure and choice of nozzle to ensure desired
application rate

- Calibrating spray equipment prior to use to ensure the rate applied is that required for
effective control of the target pest

- Cleaning all equipment after each use and/or prior to using another pesticide unless a
tank mix is the desired objective and cross contamination is not an issue

- Checking all equipment regularly (e.g., sprayers, hoses, nozzles, etc.) for signs of
uneven wear (e.g., metal fatigue/shavings, cracked hoses, etc.) to prevent equipment
failure that may result in inadvertent discharge into the environment

- Replacing all worn components of pesticide application equipment prior to application.

2.1.3 Assess weather conditions (e.g. temperature, precipitation, and wind speed) in the
treatment area to ensure application is consistent with all applicable federal
requirements.

Weather conditions may affect the results of pesticide application. Applicators must assess
the treatment area to determine whether weather conditions support pest populations and are
suitable for pesticide application.

2.2 Decision-makers' Responsibilities

As noted above, NPDES permits must contain technology-based effluent limitations. Part
2.2 of the draft 2021 PGP contains the effluent limitations that Decision-makers must perform.

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U.S. Environmental Protection Agency	Draft 2021 NPDES Pesticide General Permit Fact Sheet

Note: This document is aprepublication version, signed by all 10 U.S. EPA Regions on December 14, 2020. EPA is
submitting it for publication in the Federal Register. We have taken steps to ensure the accuracy of this version, but
it is not the official version.

The draft 2021 PGP requires all Decision-makers, to the extent Decision-makers determine the
amount of pesticide or frequency of pesticide application, to minimize the discharge of pesticides
to waters of the United States from the application of pesticides, through the use of Pest
Management Measures, as defined in Appendix A of the draft 2021 PGP, by using only the
amount of pesticide and frequency of pesticide application necessary to control the target pest.

In addition, Part 2.2 of the draft 2021 PGP requires that any Decision-maker who is
required to submit a Notice of Intent (NOI) to identify the pest problem, implement effective and
efficient pest management options, and adhere to certain pesticide use provisions. (For purposes
of the discussion below on Part 2.2 of the draft 2021 PGP, the term Decision-maker means any
Decision-maker who is or will be required to submit an NOI.) Parts 2.2.1 - 2.2.4 of the draft
2021 PGP do not apply to Decision-makers who will need to submit an NOI only because they
discharge pollutants to waters of the United States containing NMFS Listed Resources of
Concern and whose: (1) Pesticide application activities for which permit coverage is being
requested will discharge pollutants to one or more receiving waters of the United States
containing NMFS Listed Resources of Concern, but consultation with NMFS under Section 7 of
the ESA has been concluded for pesticide application activities covered under this permit; or (2)
Pesticide application activities for which permit coverage is being requested will discharge
pollutants to one or more waters of the United States containing NMFS Listed Resources of
Concern, but all "take" of these resources associated with such pesticide application activities
has been authorized through NMFS' issuance of a permit under Section 10 of the ESA, and such
authorization addresses the effects of the pesticide discharges and discharge-related activities on
federally-listed species and federally-designated critical habitat. However, these Decision-
makers must comply with all applicable conditions and/or requirements resulting from ESA
Section 7 consultation or ESA Section 10 permit.

Decision-makers are required to perform each of these permit conditions prior to the first
pesticide application covered under this permit and at least once each calendar year thereafter.
These additional technology-based effluent limitations are based on integrated pest management
principles. EPA is requiring certain Decision-makers to also comply with a different technology-
based effluent limitation than Applicators because the Agency has determined that they are the
Best Available Technology Economically Achievable for these Operators. These requirements
are aimed at reducing discharge of pesticides to waters of the United States and lessening the
adverse effects of pesticides that are applied. Each pesticide use pattern has specific limitations,
and these requirements are divided into three different sections: (1) identify the problem, (2) pest
management options, and (3) pesticide use. For each pest management area, Decision-makers
must identify the problem prior to pesticide application, consider using a combination of
chemicals and non-chemical Pest Management Measures, and perform surveillance before
pesticide application to reduce environmental impacts.

EPA is requiring these additional technology-based effluent limitation requirements from
Decision-makers and not the Applicators because the measures necessary to meet these
requirements are within the control of the Decision-makers, not the Applicators.

As stated above, these technology-based effluent limitations are based on integrated pest
management principles. Integrated pest management, as defined in FIFRA, is a sustainable

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

approach to managing pests by combining biological, cultural, physical, and chemical tools in a
way that minimizes economic, health, and environmental risks. (FIFRA, 7 U.S.C. 136r-1)
Integrated pest management is not a single pest control method but, rather, a series of pest
management evaluations, decisions and controls. In evaluating available and relevant
information, EPA found that some commercial (For-Hire Applicators) and non-commercial (e.g.,
state governments, federal governments, local governments, utilities) entities are currently
implementing integrated pest management or components of integrated pest management to
minimize pesticide use. For example, federal agencies are required to implement integrated pest
management under 7 USC 136r-1, "Federal agencies shall use Integrated Pest Management
techniques in carrying out pest management through procurement and regulatory policies, and
other activities." In addition, Executive Order 13514 (October 5, 2009) requires the head of each
federal agency to implement integrated pest management and other appropriate landscape
management practices as a means to promote pollution prevention and eliminate waste.

Below is a general discussion describing the limitations for all pesticide use patterns.
Following the general discussion are more detailed descriptions of each specific requirement
under each pesticide use pattern.

Any Decision-maker who is or will be required to submit an NOI must do the following
regardless of the pesticide use pattern, except those Decision-makers who will need to submit an
NOI only because they discharge pollutants to waters of the United States containing NMFS
Listed Resources of Concern and that also comply with provisions in Part 1.6 of the draft 2021
PGP:

Identify the Problem

Decision-makers are required to identify the pest problem, identify the target pest, and
establish an action threshold. Understanding the pest biology and ecology will provide insight
into selecting the most effective and efficient Pest Management Measures (pesticidal or non-
pesticidal methods), and in developing an action threshold. Action threshold is defined in
Appendix A of the draft 2021 PGP as the point at which pest populations or environmental
conditions cannot be tolerated, necessitating that pest control action be taken based on economic,
human health, aesthetic, or other effects. An action threshold helps determine both the need for
control actions and the proper timing of such actions. It is a predetermined pest level that is
deemed to be unacceptable. In some situations, the action threshold for a pest may be zero (i.e.,
no presence of the pest is tolerated). This is especially true when the pest is capable of
transmitting a human pathogen (e.g., mosquitoes and the West Nile virus) and/or is an invasive
species. In areas where aquatic weeds are problematic, it may be preferable to use an aquatic
herbicide as a preventive measure rather than after weeds become established. In some
situations, even a slight amount of pest damage may be unacceptable for ecological or aesthetic
reasons. Sometimes pre-emergent pesticide application is needed, as a preventive measure to
keep aquatic weeds at bay. Action thresholds, often expressed as number of pests per unit area,
can vary by pest, by site, and by season. In a new pest management program, action thresholds
may be difficult to establish and as a practical approach should first focus on major pests. As
Operators gain insight and experience into specific pest management settings, the action levels
can be revised up or down.

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

To identify the problem at a treatment area, Decision-makers may use existing data to meet
the conditions of this permit. For example, a mosquito district may use surveillance data from an
adjacent district to identify pests in their pest management area. Decision-makers may also use
relevant historical site data.

Pest Management Options

Decision-makers are required to implement efficient and effective means of Pest
Management Measures that most successfully minimize discharges of pollutants to waters of the
United States resulting from the application of pesticides. Decision-makers must evaluate both
pesticide and non-pesticide methods. Decision-makers must consider and evaluate the following
options: no action, prevention, mechanical/physical methods, cultural methods, biological
control agents, and pesticides. In the evaluation of these options, Decision-makers must consider
impacts to water quality, impacts to non-target organisms, feasibility, and cost effectiveness.
Combinations of various management options are frequently the most effective Pest
Management Measures over the long term. The goal should be to emphasize long-term control
rather than a temporary fix. For additional information, see discussion under each pesticide use
pattern.

Pesticide Use

Decision-makers are required to conduct pest surveillance in an area that is representative
of the pest problem and reduce the impact on the environment. Pest surveillance is important to
properly time the need for pest control. To reduce the impact on the environment and non-target
organisms, Operators are required to only apply pesticides when the action threshold has been
met. As noted earlier, action thresholds help determine both the need for control actions and the
proper timing of such actions.

There are additional requirements designed for each pesticide use pattern in Parts 2.2.1
through 2.2.4 of the draft 2021 PGP. For additional information and other limits on pesticide use,
see specific discussion under each pesticide use pattern.

2.2.1 Mosquito and Other Flying Insect Pests Control

Part 2.2.1.a — Identify the Problem

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

Establish densities for larval and adult mosquito or flying insect pest populations or
identify environmental condition(s), either current or based on historical data, to serve as
action threshold(s) for implementing Pest Management Measures. Decision-makers must
develop action thresholds for larval and adult mosquitoes prior to the first pesticide application
covered under this permit. The action thresholds must be re-evaluated at least once each calendar
year. As noted in the general discussion above, an action threshold is a point at which pest
populations or environmental conditions indicate that pest control action must be taken. Action
thresholds help determine both the need for control actions and the proper timing of such actions.
For example, an action threshold could be the number and distribution of service requests
received from the public. It is a predetermined pest level (or other indicator) that is deemed to be
unacceptable. For example, in Maryland, "A collection of more than 10 anthropophagous
(human biting) female mosquitoes per night of trap operation is considered to be the level which
causes discomfort and/or complaints from the majority of people. The light trap action threshold
for ground spraying of adult mosquitoes is 10-20 per trap-night. The action threshold to suppress
pest populations of adult mosquitoes by aerial spraying (application of insecticide by an aircraft)
is a light trap collection of 100 female mosquitoes. The action threshold for landing rate counts
to justify ground spraying for the control of adult mosquitoes is 3 mosquitoes in 2 minutes. The
action threshold for aerial spraying is 12 mosquitoes per minute."6 For larvae control, action
thresholds are determined by standard mosquito dipping techniques. For example, in Canyon
County Mosquito Abatement District, Idaho7, they established larvae density action levels for
Culex species (primary disease vectors) as Low: 1-5 larvae per dip; Medium: 6-10 larvae per dip;
High: > than 10 larvae per dip. The larvae density action threshold can be used to determine how
much larval control products are to be used or even if any action is to be taken. In some
situations, the action threshold for a pest may be zero (i.e., no presence of the pest is tolerated).
This is especially true when the pest is capable of transmitting a human pathogen (e.g.,
mosquitoes and the West Nile virus).

Identify the target pest(s) to develop Pest Management Measures based on
developmental and behavioral considerations for each pest. Knowledge of the developmental
biology of mosquitoes is essential to developing Pest Management Measures for mosquito
control.

Prior to the first pesticide application covered under the permit, Operators must ensure
proper identification of mosquito to better understand the biology of the target pest and develop
Pest Management Measures. Due to the great variability in developmental habitats and adult
feeding behaviors as discussed previously, proper identification is imperative in designing an
effective and efficient Pest Management Measures. Identification of the target pest will aid in
development of Pest Management Measures aimed at both the immature and adult
developmental stages. Identification of the target pest for a specific area allows 1) identification
of potential breeding sites, 2) evaluation of alternative Pest Management Measures aimed at
controlling the immature stages (habitat modification, source reduction, larvicides, biological
larvicides, and oils), and 3) assessment of potential for disease transmission.

6 http://mda.marvland.gov/plants-pests/Pages/mosauito control program description.aspx

7 http://www.canvoncountvmosauito.com/CCMADMosauitoPesticideUsePlan.pdf

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Similarly, for black flies, prior to first pesticide application covered under this permit,
Operators must ensure proper identification of the pest to develop Pest Management Measures.
Due to preferred hosts and developmental habitats, proper identification of the pest is
instrumental in determining the biology (univoltine or multivoltine), and developmental habitat
preference (e.g., flow rate, stream size, stream substrate composition), and flight range of the
target pest. By knowing these factors, a control program can 1) determine if the black fly species
warrants control activities (i.e. host preference and historical problems), 2) identify habitats and
delineate the potential area for ongoing monitoring and control activities, 3) determine frequency
of site monitoring, 4) estimate timing for pesticide application (i.e. historical seasonal
occurrence, age distribution of susceptible immature population, environmental conditions
suitable for control activity, etc.), 5) reduce discharge of pesticides into waters of the United
States.

Identify known breeding sites for source reduction, larval control program, and
habitat management. Once pests have been identified, mapping is a valuable tool in assessing
mosquito habitats and designing control programs for a specific area to minimize pesticide
discharges into waters of the United States. Maps may simply be township/city/county maps but
may also include aerial photo assessments, topographic maps, and satellite imagery where
available and/practicable. Mapping is essential to identify pest producing areas which can and
cannot be controlled using non-chemical preventative measures (e.g., source reduction). Maps
should include all potential sites for mosquito development including agricultural areas in the
specific area (e.g., hay, pasture, circle irrigation, orchards, rill irrigated field crops, and flood
irrigated pastures and farmland). Mapping should also be a priority in a surveillance program
utilizing mosquito traps, biting counts, complaints, and reports from the public. Planning in
coordination with mapping ensures the best Pest Management Measures (whether source
reduction, biological, or chemical) for each particular pest is chosen. Operators must identify
known breeding sites prior to the first pesticide application covered under this permit.

In conjunction with identifying the target pest, mapping should be considered part of
control programs aimed at black fly management. As black flies are strong fliers and will travel
great distance to obtain a blood meal, mapping should be for an extended area from the site to be
protected by control activities. Pest identification and mapping should also be a priority in a
surveillance program (both current and historical) to determine the need for initiating control
activity. Identification and mapping are both essential to planning a control program which
reduces pesticide discharges into waters of the United States.

Analyze existing surveillance data to identify new or unidentified sources of mosquito
or flying insect pest problems as well as sites that have recurring pest problems. As

discussed above, mapping is a valuable tool in assessing mosquito habitats and designing control
programs. Decision-makers must analyze existing surveillance data to identity any new source of
pest problems.

In the event there are no data for the pest management area in the past calendar year,
use other available data as appropriate to meet the permit conditions in Part 2.2.1.a.

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Decision-makers may use historical data or neighboring district data to identify the pest and
establish action thresholds.

Part 2.2.1.b — Pest Management Options

Prior to the first pesticide application covered under this permit that will result in a
discharge to waters of the United States, and at least once each calendar year thereafter
prior to the first pesticide application for that calendar year, any Decision-maker who is or
will be required to submit NOIs must select and implement efficient and effective means of
Pest Management Measures that minimize discharges resulting from the application of
pesticides to control mosquitoes or other flying insect pests. In developing the Pest
Management Measures for each pest management area, the Decision-maker must evaluate
the following management options, including a combination of these management options,
considering impact to water quality, impact to non-target organisms, feasibility, and cost
effectiveness: No action; Prevention; Mechanical/physical methods; Cultural methods;
Biological control agents; and Pesticides. Decision-makers are required to evaluate
management options and implement Pest Management Measures to minimize pesticide
discharges into waters of the United States prior to the first pesticide application covered under
this permit. For black flies, Pest Management Measures will vary by locality (i.e. stream size,
stream substrate, and stream vegetation), black fly species (5 multi/univoltine development and
host specificity), and financial concerns (i.e. accessibility to streams and size/rate of flow for the
streams). As noted above, combinations of various management options are frequently the most
effective Pest Management Measures over the long term. The goal should be to emphasize long-
term control rather than a temporary fix. Decision-makers must reevaluate every year prior to the
first pesticide application for that calendar year.

Based on problem identification, two preventive measures other than pesticides should be
evaluated for black flies. The first is reducing the number of black fly breeding areas. This may
include removal (physical and/or chemical) of vegetation and other objects in streams to reduce
number of larval habitats. The second is temporary damming of flowing stream larval
development sites to create pool habitats. As larvae require flowing water for development,
pooling can kill developing black fly larvae. However, the impact of these habitat management
options must be considered in relation to other environmental impacts on other aquatic species.
Furthermore, due to the wide variability in stream size/flow rate and the accessibility of streams
for habitat modification, these options are seldom acceptable control solutions for most black fly
developmental habitats.

The following describes the management options that must be evaluated.

No Action. No action is to be taken, although a mosquito problem has been identified. This may
be appropriate in cases where, for example, available control methods may cause secondary or
non-target impacts that are not justified, or no control methods exist.

Prevention. Prevention strategies are program activities which eliminate developing mosquito
populations through environmental modification and/or habitat management. For mosquito
control, these activities are physical methods such as habitat modification, cultural methods that
reduce sources of mosquitoes, and biological control.

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Mechanical/Physical Methods. Habitat modification, also known as physical or permanent
control, is in many cases the most effective mosquito control technique available and is
accomplished by eliminating mosquito breeding sites. Habitat modification activities have the
potential to be both effective and economical in some areas and can virtually eliminate the need
for pesticide use in and adjacent to the affected habitat. However, the ability to use prevention
strategies is dependent upon local authority and restrictions.

Cultural Methods. Cultural methods can reduce sources of mosquitoes and can be as simple as
properly discarding old containers that hold water capable of producing Aedes aegypti, Ae.
albopictus or Culex spp. or as complex as implementing Rotational Impoundment Management
(RIM) or Open Marsh Water Management (OMWM) techniques. RIM is a source reduction
strategy that controls salt marsh mosquitoes (e.g.., Ae. taeniorhynchus and Ae. sollicitans) at the
same time as significant habitat restoration is occurring. Source reduction may include; water
management, vegetation management, biological control, and pesticide use in non-waters of the
United States.

Containers provide excellent habitats for development of numerous mosquito species.

These may include but are not limited to flowerpots, cans, and tires. Container-inhabiting
mosquitoes of particular concern include, Ae. aeypti, Ae. albopictus, Cx. p. pipiens, and Cx.
salinarious. A container-breeding mosquito problem can be solved by properly disposing of such
materials, covering them, tipping them over to ensure that they do not collect water, and/or
periodic draining. Urban container-breeding mosquito control is best implemented through
education and surveillance programs.

Source reduction in freshwater lakes, ponds, and retention areas is more applicable to
artificially created areas than natural areas. Artificial ponds can be eliminated as a breeding site
simply by filling in the areas, (i.e. habitat modification). However, large permanent water bodies
and areas for stormwater or wastewater retention require other methods. Options for these areas
include minimizing and/or eliminating emergent and standing vegetation, maintenance of steep
banks, and inclusion of deep-water areas as sanctuary for larvivorous fish.

Mosquito production from stormwater/wastewater habitats can result in considerable
mosquito problems as a result of engineering, poor construction or improper maintenance.
However, mosquito populations can typically be managed by keeping such areas free of weeds
through an aquatic plant management program and maintaining water quality that can support
larvivorous fish. Culex, Coquillettidia, Mansonia, and Anopheles mosquitoes are often produced
in these habitats.

Pastures and agricultural lands are enormous mosquito producers, frequently generating
huge broods of Aedes, Psorophora, and Culex mosquitoes. Improved drainage is one effective
tool for source reduction in such habitats. The second is the use of efficient, precision irrigation
practices that will result in less standing water for those agricultural areas that require artificial
watering.

In coastal areas with extensive coastal salt marshes, there can be tremendous production of
Aedes mosquitoes, making coastal human habitation virtually impossible. Several source
reduction efforts can greatly reduce salt-marsh mosquito production through high-to mid-

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intensity management that relies upon artificial manipulation of the frequency and duration of
inundation.

Biological Control Agents. The use of biological organisms or their byproducts to combat pest
insects, such as mosquitoes, is termed biological control, or biocontrol. Biocontrol is utilization
of parasites, predators, and pathogens to regulate pest populations. Generally, this definition
includes natural and genetically modified organisms and means that the agent must be alive and
able to attack the mosquito. The overall premise is simple: Biocontrol agents that attack
mosquitoes naturally are grown in the lab and then released into the environment, usually in far
greater numbers than they normally occur, and often in habitats that previously were devoid of
them, so as to control targeted mosquito species.

One advantage of biocontrol agents is host-specificity which affords minimal disturbance
to non-target species and to the environment. However, it is this specificity and the cost of
commercializing biocontrol agents that deter development of biocontrol agents. In addition,
utilization of biocontrol requires increased capital outlay and start-up costs as well as increased
training requirements for personnel.

Biocontrol should be considered a set of tools that a mosquito control program can use
when it is economically feasible. When combined with conventional chemicals and physical
control procedures, biocontrol agents can provide short and, occasionally, long-term control.
Biocontrol, as a conventional control method, should aim at the weakest link of the life cycle of
the mosquito. In most cases, this is the larval life stage.

Mosquitofish (Gambusia affinis) are currently the most extensively used biocontrol agent.
These fish, which feed on mosquito larvae, can be placed in a variety of permanent and semi-
permanent water habitats. Differences of opinion exist on the utility and actual control benefits
derived from Gambusia implementation in an integrated pest management program with results
reported from excellent control to no control at all. Concerns over placing Gambusia in habitats
where other fish species assemblages are threatened have been ongoing. Care must be taken in
placement of this cosmopolitan species in areas where endemic fish species are sensitive to
further environmental perturbation. Additionally, use of endemic fish species in these areas of
concern deserves greater attention.

In some aquatic habitats, fish function as an excellent mosquito biocontrol mechanism.
These typically are permanent habitats where Culex and Anopheles are the primary mosquito
residents and where the mosquito densities are not excessive. However, in habitats such as salt
marshes fish are unable to control the sudden explosion of larvae produced by rainfall or rising
tides. Here, the mosquito population numerically exceeds what the fish can consume during the
brief immature mosquito developmental period. In salt marshes, fish must rely on things other
than mosquito larvae for their nutritional needs most of the time, simply because there may be
long delays between hatches of larvae. Mosquito larvae present an abundant food source, but
only for a few days during their rapid development.

Species of predacious mosquitoes in the genus Toxorhynchites have been studied in a
variety of urban areas for control of container-inhabiting mosquitoes, such as the Asian tiger
mosquito (Ae. albopictus). Toxorhynchites mosquitoes also affect mosquito populations that

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develop in the treehole environment; however, their introduction into urban container habitats
has proven unsuccessful.

In specific containers, Toxorhynchites may consume a large number of prey mosquito
larvae, such as Aedes aegypti and Ae. albopictus. However, this predator does not disperse well
enough to impact the vast number of natural and artificial containers used by these mosquitoes.
Additionally, their life-cycle is two to three times that of their prey making it impossible for
them to keep up with the other more rapidly developing mosquitoes.

Another group of biocontrol agents with promise for mosquito control is the predacious
copepods (very small crustaceans). Copepods can be readily mass reared, are easily to delivered
to the target sites, and perform well when used with insecticides.

Birds and bats are often promoted as potential biocontrol agents of adult mosquitoes.
However, while both predators eat adult mosquitoes, they do not do so in sufficient amounts to
impact the mosquito populations. Mosquitoes provide such a small amount of nutrition that birds
or bats expel more energy pursuing and eating mosquitoes than they derive from them. They are
not a primary food source for these predators. Additionally, with mosquito flight behavior being
crepuscular they are not active during the feeding periods of most birds. While bats are active
during the correct time period, they simply cannot impact the massive numbers of adult
mosquitoes available.

Bio-rational products exploit insecticidal toxins found in certain naturally occurring
bacteria. These bacteria are cultured in mass and packaged in various formulations. The bacteria
must be ingested by mosquito larvae, so the toxin is released. Therefore bio-rational products are
only effective against larvae since pupae do not feed. The bacteria used to control mosquito
larvae have no significant effects on non-target organisms. The possibility of creating a new
invasive species by the introduction of biocontrols should be considered, evaluated, and avoided.

Pesticides. There are chemical and biological pesticide products registered for use against
mosquitoes. Two biological pesticide products that are used against mosquito larvae singly or in
combination are Bacillus thuringiensis israelensis (Bti) and Bacillus sphaericus (Bs).
Manufactured Bti contains dead bacteria and remains effective in the water for 24 to 48 hours;
some slow release formulations provide longer control. In contrast, Bs products contain live
bacteria that in favorable conditions remain effective for more than 30 days. Both products are
safe enough to be used in water that is consumed by humans. In addition to the biological
pesticides, there are chemical pesticides for use against mosquitoes. As described below, once
the determination is made to use pesticides to control mosquitoes, additional requirements under
the 2016 PGP must be met.

Part 2.2.1.c. — Pesticide Use

Conduct larval and/or adult surveillance in an area that is representative of the pest
problem or evaluate existing larval surveillance data, environmental conditions, or data
from adjacent area prior to each pesticide application to assess the pest management area
and to determine when action threshold(s) is met. Pest surveillance is important for timing
pest control properly and to evaluate the potential need for pesticide use for mosquito control.

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Understanding surveillance data may enable mosquito control Operators to more effectively
target their control efforts. Decision-makers are required to conduct a surveillance program to
minimize discharges of pollutants from control activities. Surveillance is necessary not only to
establish pests' presence and abundance but also as an evaluation tool of the effectiveness of
source reduction and chemical control activities. Furthermore, surveillance should be used as an
indicator of the need for additional chemical control activities based on pre-established criteria
related to population densities in local areas.

Larval surveillance involves routine sampling of aquatic habitats for developing
mosquitoes. The primary tools used to determine larval densities and species composition are a
calibrated dip cup and/or a bulb syringe for inaccessible areas such as treeholes. The counts may
be expressed as the number of immature (larvae and pupae) mosquitoes per dip, per unit volume,
or per unit surface area of the site. However, due to natural mortality from environmental factors,
disease and predators, larval dip counts do not provide an accurate indication of the potential
adult population. Nevertheless, larval counts do indicate when chemical larval control measures
are warranted.

Adult surveillance is a key component of Pest Management Measures. Adult surveillance
can be conducted using a variety of methods including but not limited to CDC traps, New Jersey
light traps, resting site traps, egg oviposition traps, vehicle traps, and landing count rates.
Mosquito control Operators should use a variety of the available traps as adults are attracted to
different traps depending on their species, sex, and physiological condition. Trapped adults
provide information about local species composition, distribution, and density. In addition, the
need for adulticide application may also be established through the number and distribution of
service requests received from the public. Collection data also provide feedback to the mapping
and planning component of the integrated pest management program as well as to its
effectiveness and also serve to identify new sources of mosquitoes or identify recurring problem
sites.

Disease surveillance, where practical, is also a key component of Pest Management
Measures. Detecting antibodies in "sentinel" chicken flocks, equine cases, and testing dead birds
and adult mosquitoes for infections are all used to determine whether disease is being transmitted
in an area. Mosquito and vector control agencies also may test mosquitoes for viruses in their
laboratories. Although generally less sensitive than sentinel chickens, mosquito infections may
be detected earlier in the season than chicken seroconversions and therefore provide an early
warning of virus activity. However, disease surveillance is not applicable to all mosquito control
programs. In the absence of a dedicated disease surveillance program, mosquito control
Operators should stay informed of arboviral occurrence or potential for occurrence in their
control areas as determined by local, state, and/or national public health agencies.

Larval surveillance involves routine sampling of aquatic habitats for developing black flies.
Larval surveillance is primarily accomplished by collecting stream substrates (rocks, vegetation,
etc.) and examining for larval and pupal occurrence. Due to the varied developmental sites for
black larvae and their ability to move in streams relative to changes in flow patterns, quantitative
sampling will vary from site to site and in many instances, particularly with continuously
changing water levels, is not practical. Qualitative sampling is often used in lieu of quantitative

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sampling, as an indicator of egg hatch and to indicate the age distribution of developing larvae.
Qualitative sampling alone when used in conjunction with historical occurrence data can provide
a reliable indicator of the need to initiate control activities.

Adult surveillance for black flies may include sweep sampling, vacuum aspiration of
adults, and the use of silhouette traps. Traps may be simple visual attractants or may be baited
with artificial attractants (e.g., ocentol and CO2). However, as different black fly species will
respond differently in relation to different attractants, based on host preference, care must be
used in selecting attractants that will provide a representative sample of the complete black fly
spectrum present in any given location. Choice of adult sampling will in many cases be dictated
by historical occurrence of black flies in a given area. Regardless, surveillance data is a useful
tool in providing feedback to the mapping and planning component of any Pest Management
Measure.

Aside from surveillance data, Decision-makers may also evaluate environmental conditions
to assess the pest management area. For example, if the pest management area is known for pest
development after flooding then Pest Management Measures may be needed after a rainstorm.

Reduce the impact on the environment and on non-target organisms by applying the
pesticide only when the action threshold(s) has been met. Operators must apply pesticide only
as indicated by action thresholds for the pest management area. As noted above, action
thresholds, established by the Decision-maker, help determine both the need for control actions
and the proper timing of such actions. Timing pesticide application can reduce the impact on the
environment and on non-target organisms.

In situations or locations where practicable and feasible for efficacious control, use
larvicides as a preferred pesticide for mosquito or flying insect pest control when the larval
action threshold(s) has been met. Operators may use larvicides, adulticides or a combination of
both. However, when practicable and feasible, larviciding should be the primary method for
mosquito control. Larviciding is a general term for the process of killing mosquitoes by applying
natural agents or manmade pesticide products designed to control larvae and pupae (collectively
called larvicides) to aquatic habitats. Larviciding uses a variety of equipment, including aerial,
from boats, and on the ground, as necessitated by the wide range of breeding habitats, target
species, and budgetary constraints. Applications can be made using high pressure sprayers, ULV
sprayers, handheld sprayers, and back sprayers. However, larviciding is only effective when a
high percentage of the mosquito production sites are regularly treated, which may be difficult
and expensive.

There are advantages and disadvantages to aerial and ground larvicide applications. Ground
larviciding allows application to the actual treatment area and consequently to only those micro-
habitats where larvae are present. Therefore, ground larviciding reduces unnecessary pesticide
load on the environment. However, ground applications often rely on in-the-field human
estimates of the size of treatment areas and equipment output with a greater chance of
overdosing or under-dosing. Ground larviciding is also impractical for large or densely wooded
areas and exposes Applicators to greater risk of insecticide exposure.

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Aerial larviciding application methods are generally used for controlling mosquito larvae
present in large areas and areas that are inaccessible for ground application. However, failure to
treat an entire area with good larvicide coverage can result in the emergence of large adult
populations. In order to prevent poor site coverage, a global positioning system (GPS), where
economically feasible, or site flagging are necessary to increase accuracy of the pesticide
application coverage while minimizing the amount of larvicides being applied. Aerial application
does provide easier calibration of equipment due to the fact that the target area is generally
mapped, and the material is weighed or measured when loading. However, cost of aerial
application is higher than ground application (i.e. additional personnel for flagging or expensive
electronic guidance systems) and also requires special FAA licenses, training of staff, and
additional liability insurance. In addition, aerial larviciding has greater potential for non-target
impacts.

Bacillus thuringiensis var israelensis (Bti) is the primary larvicide used for black fly control
in the United States. Bti is a gram positive, aerobic, spore-forming bacterium that produces
protoxins in the form of parasporal protein crystals. In the alkaline digestive tract of black flies
and mosquitoes, the protoxins become activated into highly toxic delta-endotoxins. The
endotoxins cause a rapid breakdown in the lining of the mid-gut and necrosis of skeletal muscles,
resulting in paralysis and mortality of target insect pests. Bti is nontoxic to most non-target
organisms due to their acidic digestive systems and lack of suitable tissue receptor sites.

To minimize pesticide discharges into waters of the United States, Operators must apply
larvicides as needed for source reduction as indicated by the action threshold in situations or
locations where it is practicable and feasible to do so. The action threshold may be based on
occurrence of adults (current or historical) and/or larval sampling of stream substrates for
immature black flies. Surveillance is also a valuable tool for assessing the effectiveness of larval
control activities.

Larvicides may be applied to streams using either ground or aerial equipment. Choice of
equipment is largely dictated by stream size and accessibility. Application equipment may
include backpack sprayers, boats equipped with sprayers or metered release systems, helicopters
or fixed wing aircraft. The amount of insecticide required to treat a stream should be based on
the desired dosage and the stream discharge. Stream discharge is calculated by determining the
average width and depth of the stream and the stream velocity (discharge = width (m) x depth
(m) x velocity (m/s)). Proper calibration of insecticide delivery based on discharge is necessary
to ensure complete coverage throughout the water column in order to expose all larval habitats to
an effective insecticide dose.

A larvicide is applied across the stream width for the time specified by the application rate.
The point of application should be far enough upstream from the larval habitat to ensure proper
insecticide dispersal in the water passing over the treatment area. Operators should determine the
effective downstream carry (maximum distance at which at least 80% larval control is achieved)
of the insecticide suspension. By determining downstream carry, black fly control Operators can
limit the number of applications necessary to treat any given stream and thereby reduce pesticide
discharges into waters of the United States.

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In situations or locations where larvicide use is not practicable or feasible for
efficacious control, use adulticides for mosquito or flying insect pest control when the adult
action threshold(s) has been met. Chemical pesticide applications for adult mosquitoes,
adulticiding, is the most visible and commonly used form of mosquito control. Adulticide
applications may be used for nuisance or disease vectoring mosquitoes. Adulticiding consists of
dispersing an insecticide as a space spray into the air column, using ground or aerial equipment,
which then remains suspended in the air column through the habitat where adult mosquitoes are
flying. Any mosquito adulticiding activity that does not follow reasonable guidelines, including
timing of applications, avoidance of sensitive areas, and strict adherence to the pesticide label,
risks affecting non-target insect species.

Operators must ensure that the adulticide applications are made only when necessary by
determining a need in accordance with specific criteria that demonstrate a potential for a
mosquito-borne disease outbreak, or numbers of disease vector mosquitoes sufficient for disease
transmission, or a quantifiable increase in numbers of pestiferous mosquitoes. To determine the
need for adulticide application, at least one of the following criteria should be met and
documented by records: 1) when a large population of adult mosquitoes is demonstrated by
either a quantifiable increase in, or a sustained elevated mosquito population level as detected by
standard surveillance methods, 2) where adult mosquito populations build to levels exceeding
community standards (e.g., 25 mosquitoes per trap night or 5 mosquitoes per trap hour during
crepuscular periods), and/or 3) when service requests for arthropod control from the public have
been confirmed by one or more recognized surveillance methods.

The most common forms of adulticiding are ultra-low volume spray (ULV) and thermal
fogging. Ground adulticiding is almost exclusively conducted with ULV equipment and is the
most common method used to control mosquitoes. Ground adulticiding can be a very effective
technique for controlling most mosquito species in residential areas with negligible non-target
effects.

Aerial adulticiding is a very effective means of controlling adult mosquitoes, particularly in
inaccessible areas, and may be the only means of covering a very large area quickly in case of
severe mosquito outbreaks or vector borne disease epidemics. Aerial adulticide applications are
made using either fixed wing aircraft or rotor craft. Application is generally as ULV spray, but
some thermal fogging still occurs.

Adulticide application has its own set of conditions that determine success or failure. The
application must be at a dosage rate that is lethal to the target insect and applied with the correct
droplet size. Whether the pesticide application is ground or aerially applied, it must distribute
sufficient insecticide to cover the prescribed area with an effective dose. Typically, with ground
applications, vegetated habitats may require up to three times the dosage rates that open areas
require. This is purely a function of wind movement and its ability to sufficiently carry droplets
to penetrate foliage. In addition, aerial application is dependent upon favorable weather
conditions.

Environmental conditions may also affect the results of adulticide application. Wind
determines how the ULV droplets will be moved from the output into the treatment area.

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Conditions of no wind will result in the material not moving from the application point. High
wind, a condition that inhibits mosquito activity, will quickly disperse the insecticide over too
wide an area but at a diluted rate too low to effectively control pests. Light wind conditions (<10
mph) are the most desirable because they move the material through the treatment area and are
less inhibiting to mosquito activity. Thermal fogs perform best under very light wind conditions.

ULV application should be avoided during hot daylight hours. Thermal conditions,
particularly temperature inversion, will cause the small droplets to quickly rise, moving them
away from mosquito habitats. Generally, applications are made after sunset and before sunrise,
depending upon mosquito species activity. Some mosquitoes (Culex and Anopheles) are most
active several hours after sunset, while others (Ae. aegypti and Ae. albopictus) are more active
during the daytime, and if these species are the targets, application should be made during the
period of highest activity for the target species, provided that meteorological conditions are
suitable for application (seldom during daylight hours).

One notable exception to applications made when mosquitoes are up and flying is a
residual barrier treatment application. Barrier applications are based on the natural history and
behavioral characteristics of the mosquito species causing the problem. Barrier applications use a
residual material and are generally applied with a powered backpack sprayer to preferred resting
areas and migratory stops in order to intercept adult mosquitoes hunting for blood meals. Barrier
applications are often applied during daylight hours as a large-droplet liquid application and are
designed to prevent a rapid re-infestation of specific areas, such as recreational areas, parks,
special-event areas, and private residences. Barrier applications can help provide control of
nuisance mosquitoes for up to one week or longer.

Pesticide control of black flies in the United States historically relied upon both larvicides
and adulticides. However, adulticide use against black fly populations is no longer a common
practice. As adult black flies are seeking blood meals during the daytime, adulticide application
coincides with human activity, so daytime application is no longer a standard control procedure.
One reason for this change is due to environmental factors associated with daytime adulticide
application, particularly thermal inversions, which cause adulticide application for black fly
control to be ineffective. Furthermore, as only adults directly contacted by the adulticide
application are killed, with no residual activity against other adults immigrating to the treatment
area, adulticide applications are both ineffective and expensive. For these reasons, larvicides
which target the immature stages before development of the pestiferous adult are now the
primary means of black fly control in the United States.

Recommended Mosquito Control References

EPA recommends the following sources for additional information on Pest Management
Measures for mosquito control:

Anderson, RR and LC Harrington. 2010. Mosquito Biology for the Homeowner. Cornell
Cooperative Extension - Medical Entomology Extension. Available at:

http://blogs.cornell.edu/harrington/files/2014/01/Mosquito-Biology-for-the-Homeowner final-
2014-18iwdiw.pdf

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American Mosquito Control Association. 2009. Mosquito Information. Available at:

https://www.mosquito.org/page/mosquitoinfo?&hhsearchterms=%22mosquito+and+information

%22

American Mosquito Control Association. 2009. Mosquito Info: Control.
https://www.mosquito.org/page/control?&hhsearchterms=%22mosquito%22

California Department of Public Health. 2008. Best Management Practices for Mosquito Control
on California State Properties. Available at:

http://westnile.ca.gov/downloads.php7download id=996&filename=CDPH BMP
MosquitoControl6-0%.ydf

Commonwealth of Massachusetts Department of Food and Agriculture State Reclamation and
Mosquito Control Board. 1998. Generic Environmental Impact Report (GEIR)

For the Massachusetts Mosquito Control. Available at:
http://www.mass.gov/eea/docs/agr/mosquitos/geir-docs/geir-full-text.pdf

Florida Coordinating Council on Mosquito Control. 2009. Florida Mosquito Control - The State
of Mission as defined by mosquito controllers, regulators, and environmental managers.

Available online at:

http://mosquito.ifas.ufl.edu/Documents/Florida Mosquito Control White Paper.pdf

New York City Department of Health and Human Hygiene. 2016. Comprehensive Mosquito
Surveillance and Control Plan. Available at:

https://wwwl.nvc.gov/assets/doh/downloads/pdf/wnv/2016/wnvplan2016.pdf

Grodner, MG, J Criswell, C Sutherland, P Spradley, DL Renchie, ME Merchant, M Johnsen, and
S Sawlis. 2007. The Best Way to Control Mosquitoes - Integrated Mosquito Management
Explained. Available at: http://www.uaex.edu/publications/pdf/agll66.pdf

Kwasny, DC, M Wolder, and CR Isola. 2004. Technical Guide to Best Management Practices for
Mosquito Control in Managed Wetlands. Central Valley Joint Venture. Available at:
http://www.centralvalleviointventure.org/assets/pdf/CVJV-Mosquito-BMP.pdf

Rose, RI. 2001. Pesticides and Public Health: Integrated Methods of Mosquito Management.
Emerging Infectious Diseases 7:1.

State of Massachusetts. 2008. Massachusetts Best Management Practices and Guidance for
Freshwater Mosquito Control. Available at:

http://www.mass.gov/eea/docs/agr/mosquitos/docs/mepa/document-2-freshwater-bmp-to-mepa-
oct-24-2008.pdf

State of New Hampshire. 2008. Policy for Mosquito Control on State Lands. Available at:
http: //sos. nh. gov/ExecOrderLynch. aspx

State of New Mexico. 2008. Philosophy of Mosquito Control.
http://nmhealth.org/publication/view/guide/992/

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Washington State Department of Ecology/Water Quality Program. 2004. Best Management
Practices for Mosquito Control. Available at:
https://fortress.wa.gov/ecy/publications/publications/0310023.pdf

Recommended Black Fly Control References

EPA recommends the following sources for additional information on Pest Management
Measures for black fly control:

Commonwealth of Pennsylvania. 2009. Black Fly Suppression Program. Available at:
https://www.dep.pa.gov/Business/Water/CleanWater/BlackFlv/Pages/default.aspx

Government of Alberta - Agriculture and Rural Development. 1993. Black Fly Control.

Available at: https://open.alberta.ca/dataset/2397254#summary

Greater Los Angeles Vector Control District. 2008. Black Flies - Vector Services and
Information. Available at: http://www.glacvcd.org/vector-information/black-flies/

Metropolitan Mosquito Control District. 2009. Biting Gnat Control. Available at:
http://www.mmcd.org/biting-gnat-control/

North Carolina Cooperative Extension. 2005. Insect Notes - Black Flies and Their Control.
Available at: http://www.ces.ncsu.edu/depts/ent/notes/Urban/blackfly.htm

North Elba - Black Fly Control Dept. 2009. About the black fly control program. Available at:
http://www.northelba.org/?page=services/black-fly-control-dept

Ohio State University Extension. 1997. Factsheet - Black Flies. HYG-2167-97.

The Merck Veterinary Manual. 2016. Black Flies. Available at:

http://www.merckvetmanual.com/mvm/integumentary system/flies/black flies.html?qt=black
flies&alt=sh

Undeen, AH and DP Malloy. 1996. Use of stream width for determining the dosage rates of
Bacillus Thuringiensis Var. israelensis for larval black fly (Diptera: Simuliidae) control. Journal
of the American Mosquito Control Association. 12(2):312-315.

University of Florida. 2007. Featured Creatures - Black Flies. EENY-30. Available at
http://entomologv.ifas.ufl.edu/creatures/livestock/bfly.htm

University of New Hampshire Cooperative Extension. 2001. Black Flies. Available at:
http://www.ultimate.com/washington/wla/blackflv/

2.2.2 Weed and Algae Pest Control

Part 2.2.2.a ~ Identify the Problem

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will be required to submit NOI must do the following for each pest management area, as
defined in Appendix A. Decision-makers must identify the pest problem in their pest
management area prior to the first application covered under this permit. Knowledge of the pest
problem is an important step to developing Pest Management Measures. Re-evaluation of the
pest problem is also important to ensure Pest Management Measures are still applicable.
Decision-makers must identify the pest problem at least once each calendar year prior to the first
application for that calendar year.

Identify areas with pest problems and characterize the extent of the problems,
including, for example, water use goals not attained (e.g. wildlife habitat, fisheries,
vegetation, and recreation). Decision-makers must be well-acquainted with the unique regional
conditions of their sites and available Pest Management Measures for controlling the pest
present. Intended use goals for the water bodies that are being impeded because of nuisance pest
infestation must also be considered based on the control site. The use of the best available
mapping information to aid in identifying the problem areas is suggested. Mapping may include
aerial photo assessments, topographic maps, and satellite imagery, where available and/or
practicable. Mapping can be essential to identify problem areas which can and cannot be
controlled using non-pesticide preventative measures (e.g., mechanical control). Mapping can
also be used in plotting the regional target pest, as well as water use goals and complaints or
reports of weeds and algae from the public.

Identify target pest(s). Positive identification of the pest is required because many pests
within the same genera may require different levels and types of Pest Management Measures.
Pest identification is important when determining the best Pest Management Measures for each
pest and for determining application areas. Decision-makers should develop Pest Management
Measures based on identification of the targeted pest which occur in their area.

Identify possible factors causing or contributing to the pest problem (e.g., nutrients,
invasive species, etc.). While there may not be reasonable means to control and/or stop the
introduction and occurrence of some nuisance pest infestations, the identification of possible
sources (e.g., outflows from other water systems/bodies) may help in reducing the need for
pesticide. Potential weed and algae causes, such as changes in nutrient levels or accidental or
intentional introduction of exotic species, must be identified.

Establish any pest- and site-specific action threshold, as defined in Appendix A, for
implementing Part 2.2.2b. Any data and/or information regarding pest can be used to establish
an action threshold. An action threshold must be established.

In the event there are no data for the pest management area in the past calendar year,
use other available data as appropriate to meet the permit conditions in Part 2.2.2.a.

Decision-makers may use historical data or neighboring district data to identify the pest and
establish action thresholds.

Part 2.2.2.b — Pest Management Options

Prior to the first pesticide application covered under this permit that will result in a
discharge to waters of the United States, and at least once each calendar year thereafter

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prior to the first pesticide application for that calendar year, any Decision-maker who is or
will be required to submit an NOI must select and implement efficient and effective means
of Pest Management Measures that minimize discharges resulting from the application of
pesticides to control pests. In developing the Pest Management Measures for each pest
management area, the Decision-makers must evaluate the following management options,
including a combination of these management options, considering impact to water quality,
impact to non-target organisms, feasibility, and cost effectiveness: No action; Prevention;
Mechanical/physical methods; Cultural methods; Biological control agents; and Pesticides.
Decision-makers must evaluate management options and implement Pest Management Measures
to minimize pesticide discharges into waters of the United States prior to the first pesticide
application covered under this permit. As noted above, combinations of various management
options are frequently the most effective Pest Management Measures over the long term. The
goal should be to emphasize long-term control rather than a temporary fix. Decision-makers
must reevaluate every year prior to the first pesticide application for that calendar year. All Pest
Management Measures must be implemented in a manner that reduces impacts to non-target
species. The following describes the management options that must be evaluated.

No Action

No action is to be taken, although pest problem has been identified. This may be
appropriate in cases where, for example, available pest management options may cause
secondary or non-target impacts that are not justified, no available controls exist, or the pest
population is stable at a level that does not impair water body uses.

Prevention

Preventing introductions of possible pest is the most efficient way to reduce the threat of
nuisance species (ANS TaskForce, http://www.anstaskforce.gov/default.php). Identifying
primary pathways of introduction and actions to cut off those pathways is essential to prevention.
Through a better understanding of the transportation and introduction of pest, private entities
(aquaculture) and the public have the necessary knowledge to assist in local pest control by
reducing conditions that encourage the spread of pests in their immediate surroundings. For
example, recreational water users provide a pathway of unintentional introductions. Increasing
public awareness of weeds and algae, their impacts, and what individuals can do to prevent their
introduction and spread is critical for prevention. Other examples of prevention include: better
design of water holding sites, better management and maintenance of potential problem sites,
and volunteer removal of pest (e.g., hand weeding). Monitoring and detection also play
important roles in the prevention of the spread and introduction of weeds and algae.

Mechanical or Physical Methods

Mechanical control techniques will vary depending on the pest. Examples include
dewatering, pressure washing, abrasive scrubbing, and weed removal by hand or machine.
Mechanical and biological controls will be the appropriate method in some cases, or a part of a
combination of methods. In some instances, the need for chemical pesticide use in and adjacent
to the affected habitat can be reduced or virtually eliminated with proper execution of Pest
Management Measures.

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Cultural Methods

Cultural techniques include the use of pond dyes and water-level drawdown. The use of
certain pond dyes may help manage filamentous algae and submersed (underwater) vegetation.
Several pond colorants and one or two dyes are EPA-registered for weed control. Pond dyes and
colorants can be effective if there is little water outflow from the pond. Dyes and colorants
intercept sunlight needed by algae and other underwater plants for photosynthesis. Therefore,
they are generally ineffective on floating plants like duckweed and water lilies and emergent
(growing above the surface) plants like cattails and bulrushes. Dyes and colorants are nontoxic
and do not kill the plants, and they are safe for use in ponds for irrigation, fishing, and livestock.
However, they are not intended for use in large lakes with a lot of water flow or lakes used for
public water supplies.8

Biological Control Agents

Biological control of weeds and algae may be achieved through the introduction of
diseases, predators, or parasites. While biological controls generally have limited application for
control of weeds and algae, the Operator should fully consider this option in evaluating pest
management options.

Pesticides

Aquatic herbicides are chemicals specifically formulated for use in water to kill or control
aquatic plants. Aquatic herbicides are sprayed directly onto floating or emergent aquatic plants as
well as plants at or near the water's edge or are applied to the water in either a liquid or pellet
form. Systemic herbicides are capable of killing the entire plant. Contact herbicides cause the
parts of the plant in contact with the herbicide to die back, leaving the roots alive and able to
regrow. Non-selective, broad spectrum herbicides will generally affect all plants that they come
in contact with. Selective herbicides will affect only some plants.9

Part 2.2.2.C. — Pesticide Use

Conduct surveillance in an area that is representative of the pest problem prior to
each pesticide application to assess the pest management area and to determine when the
action threshold(s) is met. Often, each weed and algae and pest management area warrant
different Pest Management Measures tailored to regional conditions. The Pest Management
Measures should consist of combinations of mechanical, biological, and/or pesticidal control
methods. All Pest Management Measures must be conducted in a manner that minimizes impacts
to non-target species.

Decision-makers should apply chemical pesticides only after considering the alternatives
and determining those alternatives not to be appropriate Pest Management Measures. Also,
Decision-makers should conduct surveillance (e.g., pest counts or area survey) prior to

8 http://www.grounds-mag.com/mag/grounds maintenance weeds overboard/

9 https://www.re gulations.gov/document?D=EPA-HO-OW-2015-0499-0Q22
(http://www.ecy.wa.gov/programs/wq/plants/management/aqua028.html)

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application of pesticides to determine when the action threshold is met thus necessitating the
need for implementing Pest Management Measures.

Surveillance may include the relatively sophisticated transect method used in ecological
studies to evaluate species distribution, or it may consist of simply conducting visual
observations in the treated area to verify the eradication or reduction in populations of weeds and
algae following pesticide application (Getsinger et al. 2005, pp 23-25).

Reduce the impact on the environment and non-target organisms by applying the
pesticide only when the action threshold has been met. Operators must apply pesticide only as
indicated by action thresholds for the pest management area. As noted above, action thresholds
help determine both the need to implement Pest Management Measures and the proper timing of
such actions. Timing pesticide application can reduce the impact on the environment and on non-
target organisms.

Environmental factors such as temperature and dissolved oxygen content, as well as
biological factors such as stage of growth, should be considered when deciding on application
timing. Partial site pesticide applications over time may be considered to reduce risk. Pesticide
application must be limited to the appropriate amount required to control the target pests.
Methods used in applying pesticides must reduce the impact to non-target species.

Recommended Weed and Algae Control References

EPA recommends the following sources for additional information on Pest Management
Measures for weed and algae control:

Aquatic Nuisance Species Taskforce. Available at http://www.anstaskforce.gov/default.php.

Getsinger, K., Moore, M. D., Layne, C. P., Petty, D. G., L, S., Sprecher, Dibble, E. D., Karcas,
E., Maceina, M., Mudrak, V., Lembi, C., Madsen, J. D., Stewart, R. M., Anderson, L., Haller,
W., Confrancesco, A., Newman, R., & Nibling, F. (2005). Aquatic Plant Management Best
Management Practices in Support of Fish and Wildlife Habitat. Aquatic Ecosystem Restoration
Foundation. Lansing, MI.

Gettys, L. A., Haller, W. T., & Bellaud, M. (2009). Biology and control of aquatic plants.
Marietta GA: Aquatic Ecosystem Restoration Foundation. Available at
http://www.fs.usda.gov/Internet/FSE DOCUMENTS/stelprdb53735Q9.pdf

2.2.3 Animal Pest Control

Part 2.2.3.a ~ Identify the Problem

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problem is an important step to developing Pest Management Measures. Re-evaluation of the
pest problem is also important to ensure Pest Management Measures are still applicable.
Decision-makers must identify the pest problem at least once each calendar year prior to the first
application for that calendar year.

The use of the best available mapping information to aid in identifying the problem areas is
suggested. Mapping may include aerial photo assessments, topographic maps, and satellite
imagery where available and/or practicable. Mapping can be essential to identify problem areas
which can and cannot be controlled using non-pesticide preventative measures (e.g., mechanical
control). Mapping can also be used in plotting the regional distribution of desired aquatic
species, as well as water use goals and complaints or reports of pests from the public.

Identify target pest(s). Positive identification of the pest is required because many pests
within the same genus may require different levels and types of Pest Management Measures.
Animal identification is important when determining the best Pest Management Measures for
each particular pest and for determining application areas. Decision-makers must develop Pest
Management Measures based on identification of the targeted pest which occur in their area.

Identify possible factors causing or contributing to the problem (e.g., nutrients,
invasive species). While there may not be reasonable means to control and/or stop the
introduction and occurrence of some pest infestations, the identification of possible sources (e.g.,
outflows from other water systems/bodies) may help in minimizing the need for implementing
Pest Management Measures. Potential factors which could lead to the establishment of animal
populations such as accidental or intentional introduction of exotic species must be identified
before Pest Management Measures are implemented.

Establish any pest- and site-specific action threshold, as defined in Appendix A, for
implementing Part 2.2.3.b. An action threshold should be established before implementing Pest
Management Measures. Any data and/or information regarding pest can serve as an action
threshold.

In the event there are no data for the pest management area in the past calendar year,
use other available data as appropriate to meet the permit conditions in Part 2.2.3.a.

Decision-makers may use historical data or neighboring district data to identify the pest and
establish action thresholds.

Part 2.2.3.b — Pest Management Options

Prior to the first pesticide application covered under this permit that will result in a
discharge to waters of the United States, and at least once each year thereafter prior to the
first pesticide application during that calendar year, any Decision-maker who is or will be

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required to submit an NOI must select and implement efficient and effective means of Pest
Management Measures that minimize discharges resulting from the application of
pesticides to control pests. In developing the Pest Management Measures for each pest
management area, the Decision-maker must evaluate the following management options,
including a combination of management options, considering impact to water quality,
impact to non-target organisms, feasibility, and cost effectiveness: No action; Prevention;
Mechanical/physical methods; Biological control agents; and Pesticides. Decision-makers
are required to evaluate management options and implement Pest Management Measures to
minimize pesticide discharges into waters of the United States prior to the first pesticide
application covered under this permit. As noted above, combinations of various management
options are frequently the most effective Pest Management Measures over the long term. The
goal should be to emphasize long-term control rather than a temporary fix. Decision-makers
must reevaluate every year prior to the first pesticide application for that calendar year. All Pest
Management Measures must be conducted in a manner that minimizes impacts to non-target
species. The following describes the management options that must be evaluated.

No Action

No action is to be taken, although an animal pest problem has been identified. This may be
appropriate in cases where, for example, available control methods may cause secondary or non-
target impacts that are not justified, or no available controls exist.

Prevention

Preventing introductions of possible nuisance species is the most efficient way to reduce
the threat of aquatic nuisance animals (ANS Task Force, 2009). Identifying primary pathways of
introduction and actions to cut off those pathways is essential to prevention. Through a better
understanding of the transportation and introduction of animals, private entities (aquaculturists)
and the public have the necessary knowledge to assist in local animal control by reducing
conditions that encourage the spread of animals in their immediate surroundings. For example,
recreational water users provide a pathway of unintentional introductions. Increasing public
awareness of pests, their impacts, and what individuals can do to prevent their introduction and
spread is critical for prevention. Other examples of prevention include, better design of water
holding sites, better management and maintenance of potential problem sites, and volunteer
removal of pest species (e.g., fishing). Monitoring and detection also play important roles in the
prevention of the spread and introduction of pests.

Mechanical or Physical Methods

Mechanical and biological controls will be the appropriate methods in some cases of pest
control, or a part of a combination of methods. Mechanical control techniques will vary
depending on the pest. Examples include fishing, dewatering, netting, electrofishing, pressure
washing, use of electric fences, and abrasive scrubbing.

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Biological Control Agents

Biological control of animals may be achieved through the introduction of diseases,
predators, or parasites. While biological control generally has limited application for control of
animals, Decision-makers should fully consider this option.

Pesticides

Chemical and biological pesticides such as lampricides, molluscides, insecticides, and
piscicides, are registered for use to control animal pests. These pesticides are specifically
formulated for use in water where aquatic nuisance animals occur. In some cases, pesticide use
may impact non-target species. As described below, once the determination is made to use
pesticides, additional requirements must be met.

Part 2.2.3.C. — Pesticide Use

Conduct surveillance in an area that is representative of the pest problem prior to
each application to assess the pest management area and to determine when the action
threshold(s) is met. Often, each animal and pest management area warrant different Pest
Management Measures, tailored to the regional conditions. Pest Management Measures should
consist of combinations of mechanical, biological, and/or pesticidal control methods. All Pest
Management Measures must be conducted in a manner that minimizes impacts to non-target
species.

Operators must apply chemical pesticides only after considering the alternatives and
determining those alternatives not to be appropriate Pest Management Measures. In some
instances, the need for chemical pesticide use in and adjacent to the affected habitat can be
reduced or virtually eliminated with proper execution of alternative strategies and best
management practices. If pesticides are used, they must only be used as needed as determined by
an action threshold, and Pest Management Measures must be implemented, including use of the
minimum effective application rate. Also, the Decision-maker must conduct surveillance (e.g.,
pest counts or area survey) prior to application of pesticides to determine when the action
threshold is met that necessitates the need for implementing Pest Management Measures.

Surveillance may include the relatively sophisticated transect method used in ecological
studies to evaluate species distribution, or it may consist of simply conducting visual
observations in the treated area to verify the eradication or reduction in populations of aquatic
nuisance animals following pesticide application (Getsinger et al. 2005, pp 23-25).

Reduce the impact on the environment and non-target organisms by evaluating site
restrictions, application timing, and application method in addition to applying the
pesticide only when the action threshold(s) has been met. The pest and site restrictions (water
use, water movement, etc.) must be identified when choosing an appropriate pesticide.
Environmental factors such as temperature as well as biological factors such as migration timing
should be considered when deciding on application timing. Partial site pesticide applications
over time may be considered to minimize risk to non-target organisms.

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Pesticide application must be limited to the appropriate amount required to control the
target pests. Methods used in applying pesticides must minimize the impact to non-target
species. For piscicides, chemical deactivation is currently required for all lotic (flowing water)
environments. Management agencies typically work downstream throughout the watershed in
consecutive treatments as this will require the least amount of chemical deactivation. Most
invertebrates repopulate treated areas through immigration (typically in the direction of flow); as
such headwater streams/tributaries seem to be effective at accomplishing this. EPA also notes
that not all piscicides are that harmful to invertebrate populations (e.g., antimycin is more
selective for scaled fish). It can be difficult to know the point at which headwater streams are
"fishless"; however, most fishery management agencies do not treat streams unless they are
considered a refuge for target species.

Recommended Animal Pest Control References

EPA recommends the following sources for additional information on Pest Management
Measures for animal control:

Aquatic Nuisance Species Taskforce. Online: http://www.anstaskforce.gov/.

2.2.4 Forest Canopy Pest Control

Part 2.2.4.a ~ Identify the Problem

Establish any pest- and site-specific action threshold, as defined in Appendix A, for
implementing Part 2.2.4.b. Decision-makers must develop action thresholds for the target pests
prior to the first pesticide application as covered under the draft 2021 PGP. The action thresholds
must be re-evaluated at least once each calendar year. As noted in the general discussion above,
an action threshold is a point at which pest populations or environmental conditions indicate that
Pest Management Measures must be taken. Action thresholds help determine both the need for

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implementing Pest Management Measures and the proper timing of such actions. It is a
predetermined pest level that is deemed to be unacceptable.

Identify target pest(s) to develop Pest Management Measures based on developmental
and behavioral considerations for each pest. Pest identification is a key activity for
implementation of a forest canopy pest control system. Pest identification should only be
conducted by personnel with adequate training and experience with the pests. While numerous
similar pests (insects and/or pathogens) may be present in any given location, only a few of the
representative pest may constitute a threat which requires control activities. Through proper pest
identification informed control decisions can be made based on the development biology of the
pest (susceptible development stage), pest mobility (potential rate of spread), timing of selected
Pest Management Measures, applicable control techniques, and most effective chemical
pesticides for the target pests (insecticide class, resistance, etc.). Failure to identify pests can lead
to unwarranted control activities and/or the need for chemical application with potential for
discharges of pollutants into waters of the United States. Control for each specific pest is also
predicated on the status of the pest as native recurring, quarantine restricted, or designated as an
invasive species.

Identify current distribution of the target pest and assess potential distribution in the
absence of Pest Management Measures. Control activities are warranted only after exact pest
identification and delineation of the extent of the pest infestation. As forest canopy pest control
can involve treating large expanses of forests, mapping is also an important component in
identification of the problem. The distribution of the pest, usually insects, within the area of
infestation can impact the selection of Pest Management Measures. In addition, mapping of the
pest infestation will allow evaluation of the actual/potential spread of the infestation (e.g., pest
biology, pest mobility, and host availability) and also serve as a tool to evaluate the effectiveness
of the Pest Management Measures. Mapping can also provide essential information for
assessment of economic damages that can result from the current and potential pest infestation
and failure to control the pest. Management decisions can thereby be based on cost/benefit
evaluations based on the current and potential distribution of any pest.

The third component of problem identification is to determine the potential economic
impact of not controlling the pest. By establishing economic thresholds, it is possible to
determine pest action thresholds which warrant control activities. However, control decisions
must take into account not only the projected economic impact of the current pest infestation but
also the potential of the pest infestation to spread. Therefore, control decisions based on
economic impact must in turn rely on proper pest identification, pest biology, and current and
potential pest distribution.

In the event there are no data for the pest management area in the past calendar year,
use other available data as appropriate to meet the permit conditions in Part 2.2.4.a.

Decision-makers may use historical data or neighboring district data to identify the pest and
establish action thresholds.

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Part 2.2.4.b. — Pest Management Options

Prior to the first pesticide application covered under this permit that will result in a
discharge to waters of the United States, and at least once each calendar year thereafter
prior to the first pesticide application for that calendar year, any Decision-maker who is or
will be required to submit an NOI must select and implement efficient and effective means
of Pest Management Measures that minimize discharges resulting from the application of
pesticides to control pests. In developing the Pest Management Measures for each
management area, the Decision-maker must evaluate the following management options,
including a combination of management options, considering impact to water quality,
impact to non-target organisms, feasibility, and cost effectiveness: No action; Prevention;
Mechanical/physical methods; Cultural methods; Biological control agents; and Pesticides.
Pest control activities in forest canopy management programs may be warranted following
problem identification and based solely on pest occurrence (e.g., quarantine pest, invasive
species). However, in many instances control activities may only be necessary based on pest
population distribution and/or pest densities. To minimize the need for pest control while also
producing the best control results, Pest Management Measures appropriate for the specific
problem site(s) must be developed. A site-specific management plan will consider biotic (e.g.,
plant and animal species community structure) and abiotic (e.g., environmental) factors.
Combinations of various management options are frequently the most effective Pest
Management Measures over the long term. The goal of Pest Management Measures in forest
canopy pest control should be to emphasize long-term control rather than a temporary fix.

All Pest Management Measures must be conducted in a manner that minimizes impacts to
non-target species. The following is a discussion of the relevant management options as they
might be implemented for forest canopy pest control.

No Action

No action is to be taken, although a pest problem has been identified. This may be
appropriate in cases where available control methods may cause secondary or non-target impacts
or where aesthetic/economic losses are not anticipated.

Mechanical/Physical Methods

Mechanical and biological controls will be the appropriate method in some cases, or a part
of a combination of methods. In some instances, the need for chemical pesticide use in and
adjacent to the affected habitat can be reduced or virtually eliminated with proper execution of
alternative measures and best management practices.

Mechanical control techniques will vary depending on the pest. An example of mechanical
control in a forest canopy would be egg mass removal (e.g., gypsy moth).

Cultural Methods

Cultural control methods are Pest Management Measures that make the habitat unsuitable
for a pest. An example of a cultural method to manage pests of the forest canopy would be to

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select a different species of tree to plant, or to plant resistant varieties of trees. Maintaining the
trees in good health to discourage pests is another method of cultural control.

Biological Control Agents

Biological control of forest canopy pests may be achieved through the
introduction/enhancement of diseases, predators, or parasites. In addition, forest canopy pest
control programs aimed specifically at insects may also utilize sterile insect release, mating
disruption, and biological pesticides. While biological controls generally have limited
applications for forest canopy pest control programs, they should be fully considered as an
option in the development of Pest Management Measures. The latter two control approaches are
often utilized when controlling for gypsy moth.

Pesticides

Several chemical and biological pesticides are available that may be used to reduce
defoliation of the trees. These pesticides are typically used when pest populations are high, and
the action threshold has been reached. They are aerially applied. As described below, once the
determination is made to use pesticides, additional requirements must be met.

Part 2.2.4.C. — Pesticide Use

Conduct surveillance in an area that is representative of the pest problem prior to
each application to assess the pest management area and to determine when the pest action
threshold is met. Decision-makers must apply pesticides only as needed as determined by pre-
established criteria and pest action thresholds. Decision-makers must establish a pest action
threshold that warrants pesticide application based on problem identification and pest
surveillance. In order to establish pest densities and determine when pest action thresholds have
been met, forest canopy pest control programs must include pest surveillance activities as an
integral component of Pest Management Measures. Pest surveillance is necessary to detect the
presence (or confirm the absence) and magnitude of pest populations in a given location and
precisely pinpoint zones of infestation. Surveillance activities will vary according to the pest
(insect, weed, or pathogen) but in general should include observations of pest numbers,
developmental stage of the current infestation, and biotic factors which would enhance
development/expansion of pest populations (e.g., weather, crowding, predators, pathogens, etc.).

Pest surveillance will vary according to pest type and species. For insect pests, surveillance
activities may include, but not be limited to, pheromone traps, sticky traps, light traps,
defoliation monitoring. In some cases, traps used in surveillance activities have been developed
to the extent that they alone provide adequate control of the targeted pest, thus eliminating the
need for pesticides completely. Conversely, in the instance of quarantine pests or invasive
species, pest identification alone may suffice to fulfill surveillance requirements and indicate
need for control measures. Regardless, surveillance should take into account local environmental
conditions and projected environmental conditions, which would support development and/or
spread of the pest population and which would limit the choice or effectiveness of control
activities.

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It is also important to continue surveillance following control activities to assess the
efficacy of Pest Management Measures and to monitor for new pests. Surveillance can determine
if the current techniques are effective and whether additional Pest Management Measures are
required, particularly pesticide application. Based on follow-up surveillance activity, Decision-
makers can make informed decisions which serve to increase the effectiveness of their control
programs and minimize the potential for pollutant discharges to waters of the United States.
Surveillance is necessary not only to establish the pest presence and its abundance but also as an
evaluation tool of the effectiveness of chemical control activities. Furthermore, surveillance
should be used as an indicator of the need for additional chemical control activities based on pre-
established criteria related to population densities in local areas.

Reduce the impact on the environment and non-target organisms by evaluating the
restrictions, application timing, and application methods in addition to applying the
pesticide only when the action threshold(s) have been met. Forest canopy pest and site
restrictions (water use, water movement, etc.) must be identified when choosing an appropriate
pesticide. For instance, with gypsy moth control, a biological insecticide, Bacillus thuringiensis
kurstaki, is usually selected. However, if endangered or threatened butterfly or moth species are
in the area, a viral insecticide that specifically targets gypsy moth larvae should be considered.
Environmental factors such as temperature, as well as biological factors such as migration
timing, should be considered when deciding on application timing. Partial site pesticide
applications over time may be considered to minimize risk to non-target organisms. Pesticide
application must be limited to the appropriate amount required to control the target pests.
Methods used in applying pesticides should weigh the potential impact to non-target species.

Evaluate using pesticides against the most susceptible developmental stage. For forest
canopy pests, pesticides should be selected that target the most susceptible life stage. Gypsy
moth caterpillars are susceptible to control by chemical pesticides, or by ingestion of
nucleopolyhedrosis virus occlusion bodies.

Recommended Forest Canopy Pest Control Reference

EPA recommends the following sources for additional information on Pest Management
Measures for forest canopy pest control:

Emily Grafton and Ralph Webb. Homeowner's guide to gypsy moth management. West Virginia
University Extension Service. http://www.ni.gov/agriculture/divisions/pi/pdf/GMguide.pdf

USDA. (rev. 2019). Gypsy Moth Program Manual.

http://www.aphis.usda.gov/import export/plants/manuals/domestic/downloads/gypsy moth.pdf
USDA. 2016. Asian Gypsy Moth Factsheet.

http://www.aphis.usda.gov/publications/plant health/content/printable version/fs phasiangm.pdf

Reardon, Podgwaite, and Zerillo. GYPCHEK- Environmentally Safe Viral Insecticide for Gypsy
Moth. FHTET-2012-01. 2nd ed. March 2016. U.S. Department of Agriculture, Forest Service.
http://www.fs.fed.us/foresthealth/technology/pdfs/Gvpchek FHTET-2012-01 2ndEd.pdf

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Kucera, Daniel and P. Orr. Spruce Budworm in the Eastern United States. U.S. Department of
Agriculture, Forest Service. Forest Insect and Disease Leaflet 160.
https://www.fs.usda.gov/Internet/FSE DOCUMENTS/fsbdev2 042853.pdf

Michael, Jerry. 2004. Best Management Practices for Silvicultural Chemicals and the Science
behind Them. Water, Air, and Pollution: Focus. 4(1), 95-11

3. Water Quality-Based Effluent Limitations

In addition to technology-based effluent limitations for all discharges of pollutants, the
CWA requires additional effluent limitations that are as stringent as necessary to achieve water
quality standards. These are called water quality-based effluent limitations (WQBELs). Permit
writers are to assess whether the technology-based effluent limitations are protective of water
quality standards, and if not, permit writers must also include WQBELs as necessary to ensure
that the discharge of pollutants will not cause an excursion above any state water quality
standard, including state narrative criteria for water quality (see 40 CFR 122.44(d)). In
developing WQBELs, permit writers must consider the potential impact of every proposed
surface water discharge of pollutants on the quality of the receiving water. Unlike individual
permits that include requirements tailored to site-specific considerations, general permits, while
tailored to specific industrial processes or types of discharges of pollutants (e.g., from the
application of pesticides), often do not contain site-specific WQBELs. Instead, in general, EPA
includes a narrative statement that addresses WQBELs. In this permit the WQBEL is as follows:

All Operators must control discharges as necessary to meet applicable numeric and
narrative state, territory, or tribal water quality standards, for any discharges authorized
under this permit, with compliance required upon beginning such discharge.

If at any time an Operator becomes aware (e.g., through self-monitoring or by
notification from the state, tribe, or territory), or EPA determines, that a discharge
causes or contributes to an excursion of any applicable water quality standards, the
Operator must take corrective action as required in Part 6 up to and including the
ceasing of the discharge, if necessary.

The first sentence includes the general requirement to control discharges of pollutants as
necessary to meet water quality standards, while the second sentence implements this
requirement in more specific terms by imposing on Operators a responsibility to take corrective
action in response to an excursion of applicable water quality standards, whether discovered by
EPA or by the Operator. Failure to take such corrective action is a violation of the permit.
Additionally, the permit includes a provision, in Part 1.2.3 of the draft 2021 PGP, that specifies
that EPA may determine that additional technology-based and/or water quality-based effluent
limitations are necessary, or may deny coverage under this permit and require submission of an
application for an individual NPDES permit, as detailed in Part 1.3.

Each Operator is required to control its discharge of pollutants as necessary to meet
applicable water quality standards. In general, EPA expects that compliance with the other
conditions in this permit (e.g., the technology-based limitations, corrective actions, etc.) will

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result in discharges of pollutants that are controlled as necessary to meet applicable water quality
standards based on the cumulative effect of the following factors, which are described below:

(1) Under FIFRA, EPA evaluates risk associated with pesticides and mitigates

unreasonable ecological risk. Compliance with FIFRA is required. (See Part III. 1.5 of
the fact sheet.)

(2) In developing the PGP, EPA evaluated national-scale ambient monitoring data, as well as the
frequency of the identification of specific pesticides as the cause of water impairments, to assess
whether pesticide residues are currently present in waters at levels that would exceed water
quality standards. The monitoring data, although limited in scope, show that, in most samples,
most pesticides were below ambient water quality criteria or benchmarks developed by EPA's
Office of Pesticide Programs (OPP). For the assessment of the USGS National Water-Quality
Assessment Program's 1992-2001 data, ambient water quality criteria were available for 7 of the
83 analytes and one or more OPP benchmarks were available for 60 of the 83 analytes. For the
small number of pesticides found in monitoring data to be present above such benchmarks, the
evaluation, as summarized in Appendices B and C of the fact sheet for the 2011 PGP, also
documents risk mitigation actions taken by EPA (such as cancellation of pesticide uses) that EPA
expects have reduced the levels of those pesticides in water EPA also assessed the study USGS
National Water-Quality Assessment Program (NAWQA) released in 2014. A summary of the
evaluation and risk mitigation actions taken by EPA is available in Appendices B and C of the
fact sheet for this permit.

(3) Technology-based effluent limitations in the draft 2021 PGP provide further protections
beyond compliance with existing FIFRA requirements.

(4) Biological pesticides discharged to waters, by regulatory definition, do not work
through a toxic mode of action. For chemical pesticides, the discharges of pollutants
covered under the draft 2021 PGP are the residues after the pesticide has performed its
intended purpose. Thus, the residue will be no higher than, and in many instances,
lower than, the concentration of the pesticide as applied.

(5) The draft 2021 PGP excludes pesticide applications that result in discharges of any
pollutant to (1) waters impaired for an active ingredient of that pesticide or a degradate
of such an active ingredient, or (2) any Tier 3 waters (i.e., outstanding national resource
waters) except for pesticide applications made to restore or maintain water quality or to
protect public health or the environment that either do not degrade water quality or only
degrade water quality on a short-term or temporary basis.

(6) EPA has no evidence in the record that implementation of the 2011 and 2016 PGP has
resulted in documented water quality problems.

In addition to the six factors identified above, EPA cannot issue an NPDES permit until the
state, territory or tribe in which the discharge originates certifies that the discharge will comply
with applicable provisions of the CWA or waives certification. Therefore, Part 9 of the final
2021 PGP will include conditions included by States, and authorized Tribes in their CWA § 401
certification actions on the 2021 PGP, which meet the requirements of CWA Section 401 and
EPA's CWA Section 401 implementing regulations. 40 C.F.R. § 124.53(e)(1).

This draft 2021 PGP requires Operators to control discharges of pollutants as necessary to
meet applicable water quality standards. When the Operator or EPA determines a discharge of

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pollutants will cause or contribute to an excursion above any WQS, including failure to protect
and maintain existing designated uses of receiving waters, the Operator must take corrective
action to ensure that the situation is eliminated and will not be repeated in the future. (See Part
6.0 of the draft 2021 PGP). If additional Pest Management Measures are required, the Operator is
required to follow and document, as applicable, the process for Pest Management Measure
selection, installation, implementation and maintenance, and cooperate to eliminate the identified
problem within the timeframe stipulated in Part 6.0 of the draft 2021 PGP.

(1) Under FIFRA, EPA evaluates risks associated with pesticides and considers mitigation
measures to address risks that exceed levels of concern.

Background

EPA regulates the use of pesticides under the Federal Insecticide, Fungicide, and
Rodenticide Act (FIFRA). In general, FIFRA authorizes EPA to register each pesticide product
intended for distribution or sale in the United States. To register a pesticide, the Agency must
determine that its use in accordance with the label will not cause "unreasonable adverse effects
on the environment." (see, e.g., FIFRA sec. 3(c)(5)). FIFRA defines that term to mean, in part,
"any unreasonable risk to man or the environment, taking into account the economic, social, and
environmental costs and benefits of the use of any pesticide" (FIFRA sec. 2(bb)). The
"unreasonable adverse effects" standard requires EPA, in effect, to balance the human health and
ecological risks of using a pesticide against its economic, social, human health, and ecological
benefits. Pesticides are registered for sale and distribution only if EPA determines that the
benefits outweigh the risks. In making decisions on whether to register a pesticide, EPA
considers the use directions on proposed product labeling and evaluates data on product
chemistry, human health, ecological effects, and environmental fate to assess the potential risks
associated with the use(s) proposed by the applicants for registration and expressed on the
labeling. Among other things, the Agency evaluates the risks to human health and the
environment (including water quality) posed by the use of the pesticide.

As stated above, EPA reviews and approves pesticide product labeling. EPA implements
risk mitigation measures identified through the risk assessment process by placing use
restrictions and warnings on labeling to ensure the use of the pesticide (under actual use
circumstances and commonly accepted practice) will not cause any "unreasonable adverse
effects on the environment." It is a violation under FIFRA sec. 12(a)(2)(G) (FIFRA's "misuse"
provision) to use a registered pesticide inconsistent with its labeling.

After a pesticide has been registered, changes in science, public policy, and pesticide use
practices will occur over time. FIFRA, as amended by the Food Quality Protection Act of 1996,
mandates a registration review program, under which the Agency periodically reevaluates
pesticides to ensure that as the ability to assess risk evolves and as policies and practices change,
all registered pesticides continue to meet the statutory standard of no unreasonable adverse
effects to human health or the environment. The Agency is implementing the registration review
program pursuant to Section 3(g) of FIFRA and will review each registered pesticide every
15 years to determine whether it continues to meet the FIFRA standard for registration.
Information on this program is provided at: http://www.epa.gov/pesticide-reevaluation.

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Ecological Risk Assessment

The following is a discussion about the FIFRA risk assessment process with a focus on
Ecological (specifically aquatic) Assessments. Entities seeking pesticide registrations bear the
burden of demonstrating their products meet the statutory standard under FIFRA. As set forth in
40 CFR Part 158, applicants for pesticide registrations must provide EPA with a suite of product
chemistry, residue chemistry, toxicity, environmental fate, and ecotoxicity studies, to support an
application for registration. To support outdoor uses, studies are required that provide
information related to the environmental fate and transport of the chemical and that measure the
acute and chronic toxicity to terrestrial and aquatic organisms. These studies, along with open
literature that meet data quality guidelines, are the basis for the ecological risk assessments. The
ecological risk assessment combines the results of an environmental exposure assessment and an
ecological effect assessment for a pesticide active ingredients to produce a quantitative measure
of potential risk.10 A risk characterization is also presented to put the quantitative assessment of
risk in the context of other lines of evidence, such as available monitoring data and incident
reports, and to discuss uncertainties in the risk assessment. The quantitative and qualitative
determination of potential ecological risk is independent of economic or other benefit
considerations.

Aquatic Exposure Characterization

EPA estimates pesticide concentrations in aquatic environments to determine if exposure to
a pesticide active ingredient is at a level that could cause unreasonable adverse effects to aquatic
organisms. EPA estimates pesticide concentrations in water using peer-reviewed simulation
modeling because there are not sufficient monitoring data to estimate exposure to aquatic
organisms under all potential use conditions. When available, monitoring data are used to help
characterize aquatic exposure.

EPA also estimates potential exposure from uses involving direct application to water. The
model used for pesticides applied directly to water uses environmental fate data to simulate
partitioning of the pesticide between the water column and bottom sediment in a standard rice
paddy. This modeling is conservative because it does not simulate degradation of the applied
pesticide, as would be necessary to estimate the amount of residue remaining after the pesticide
product had performed its intended function. Depending on the rate of degradation, the initial
concentration as estimated by the model could be much higher than the residual concentration
remaining after pesticide application has been completed. Additionally, this modeling scenario is
conservative because the resulting exposure estimate is the concentration in the paddy water
itself, not taking into account dilution which would occur when paddy water is diluted by
precipitation or when it is released into a receiving water body. See the U.S. EPA. 2004.
Overview of the Ecological Risk Assessment Process in the Office of Pesticide Programs. Office
of Prevention, Pesticides, and Toxic Substances. Office of Pesticide Programs. Washington, D.C.

10 As part of the risk assessment, EPA also examines available information to determine the need to expand
beyond the focus on the active ingredient to consider pesticide formulation, inert ingredients, or degradates.

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January 23, 2004. https://www.epa.gov/endangered-species/ecological-risk-assessment-process-
under-endangered-species-act

As discussed above, when available, EPA uses ambient water monitoring data as a line of
evidence to characterize aquatic exposure in ecological and human health risk assessments. The
United States Geological Survey (USGS) maintains several sources of pesticide monitoring data.
These sources include the National Water Quality Assessment program (NAWQA), the Toxic
Substances Hydrology Program, and the National Stream Quality Accounting Network
(NASQAN). EPA sources of water monitoring data include STORET, a storage and retrieval
database of national water quality information, the Safe Drinking Water Information System
(SDWIS), Office of Water compliance monitoring data, and the USGS/EPA Reservoir
Monitoring Program. In addition to the federal data sources, monitoring data are sometimes
available from States, pesticide registrants, and the open literature.

These monitoring data are evaluated on a case-by-case basis to help characterize the
likelihood, extent, and nature of pesticide concentration in water under current use practices and
actual field conditions. EPA considers the locations and frequency of sampling, the analytical
methods, the detection limits, and the purpose of the monitoring studies from which the data are
derived when determining how such data will be incorporated into the FIFRA risk assessment
and the usefulness of the monitoring data for an aquatic exposure assessment. For example, a
monitoring study targeted to measure concentrations of a pesticide in a watershed with high
agricultural use of that pesticide will not provide much insight on the potential exposure from its
use as a mosquito adulticide. Similarly, a general survey of ambient water quality might not
necessarily target specific pesticide use areas or the time of year when pesticide concentrations
may be at their peak, and for this reason may not provide a reliable estimate of acute exposure.
However, if monitoring data from such a study shows higher confirmed detections than
estimated by modeling, the higher monitoring values typically would be used in the risk
assessment.

Aquatic Effects

To determine if a pesticide is sufficiently toxic at its estimated exposure concentrations to
cause unreasonable adverse effects in the environment, EPA reviews available ecotoxicity data.
These data may come from a number of sources, including direct guideline study submissions
required in support of registration, and open literature data retrieved through ECOTOX11. The
typical assessment endpoints for pesticide ecological risk assessments are reduced survival from
direct acute exposures and survival, growth, and reproductive impairment from direct chronic
exposures. As noted in the OPP Overview12 document, which describes the process OPP uses to

11 U.S. EPA. 2007. Ecotoxicity Database (ECOTOX) Mid-Continent Ecology Division, National Health
and Environmental Effects Research Laboratory. U.S. Environmental Protection Agency, Office of Research and
Development, https://www.epa.gov/chemical-research/ecotoxicologv-database.

12 U.S. EPA. 2004. Overview of the Ecological Risk Assessment Process in the Office of Pesticide
Programs. Office of Prevention, Pesticides, and Toxic Substances. Office of Pesticide Programs. Washington, D.C.
January 23, 2004. Support Document 1: Study Classification used by EFED in Data Evaluation Records (DERs)
http://www.epa.gov/oppfeadl/endanger/consultation/ecorisk-overview.pdf

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conduct ecological risk assessment under FIFRA, OPP evaluates other data on sublethal effects
in addition to direct effects on survival, growth, and reproduction.

In general, the current FIFRA data regulations require studies that include but are not
limited to a suite of aquatic toxicity studies for effects characterization. These test requirements
are defined for each chemical class by use category (40 CFR Part 158 Subpart D; Wildlife and
Aquatic Organism data requirements;

http://edocket.access.gpo.gov/cfr 2007/iulqtr/40cfrl58.490.htm) and are performed on a limited
number of laboratory test organisms in the following broad taxonomic groupings:

- Freshwater fish,

- Freshwater invertebrates,

- Estuarine/marine fish,

- Estuarine/marine invertebrates, and

- Algae and aquatic plants.

Within each of these very broad taxonomic groups, the most sensitive acute and chronic
toxicity value is selected from all available test data, including open literature and registrant
submissions. If additional toxicity data for more species of organisms in a particular group are
available, the most sensitive toxicity values from all sources for other species/studies that meet
data quality standards are used in the risk assessment.13 Aquatic toxicity data are required for
each active ingredient, but aquatic toxicity data are also required on the typical end use product
for any pesticide that will be introduced directly to aquatic environments (40 CFR Part 158.630).

Risk Characterization

Risk characterization is the integration of effects and exposure characterization to determine the
ecological risk from the use of the pesticide and the likelihood of effects on non-target species
based on the pesticide-use scenarios. In FIFRA screening-level assessments, OPP relies on the
deterministic risk quotient (RQ) method to compare estimated exposure to toxicity endpoints.
Estimated environmental concentrations (EECs) derived in the exposure characterization are
divided by acute and chronic toxicity endpoints identified in the effects characterization. Risk
quotients are then compared to the Agency's Levels of Concern (LOCs). These LOCs are the
Agency's interpretative policy and are used to analyze the potential risk to non-target organisms
and the need to consider regulatory action. These criteria are used to indicate when a pesticide
use as directed on the label has the potential to cause adverse effects on non-target organisms. If
a risk of concern is identified, risk mitigation measures are considered.

Risk Mitigation

EPA acknowledges that there are uncertainties in its pesticide risk assessments (see full
discussion below), nonetheless the Agency reduces the risks of concern by imposing additional
restrictions on the use of a pesticide to reduce pesticide concentrations in the aquatic
environment. Mitigation measures may include limits on the amount and frequency that a
pesticide may be applied, or the application methods may be restricted to limit off-site transport.

13 Ibid U.S. EPA 2004

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Mitigation may also limit the geographical areas to which a pesticide can be applied or may
include mandatory buffer distances from sensitive habitats. Mitigation measures are
implemented through product labeling instructions, with which pesticide users are required to
comply.

In some cases, EPA restricts the use of a pesticide so that levels of pesticide predicted by
the model to reach water are below the relevant aquatic benchmarks (see Aquatic Benchmarks
discussion below). In other cases, using the FIFRA risk-benefit balancing standard, EPA may
permit the use of a pesticide even though the estimated water concentration might exceed a
relevant benchmark. In such cases, the decision incorporates consideration of the benefits of the
pesticide use and other lines of evidence, such as any available National Recommended Water
Quality Criterion for ambient water quality, concerning the conservativeness of the modeling
assessment and available monitoring data.

Uncertainties with Risk Assessment and Mitigation

For the majority of pesticides, the Agency relies on simulation modeling to predict
potential aquatic exposure following pesticide applications. There are uncertainties embedded in
the FIFRA exposure assessment, for example, the extent to which the simulated scenario
represents actual use conditions in terms of hydrologic vulnerability and the amount and
frequency with which pesticides are applied. In order to account for the inherent uncertainty, the
Agency uses a combination of parameters and assumptions in the models that results in estimated
potential exposure concentrations that are high-end and are not likely to underestimate actual
aquatic exposure. This allows the Agency to identify pesticides that are not likely to pose a risk
to aquatic life.

In the effects characterization under FIFRA, the lowest acute and chronic toxicity values
from the most sensitive species tested in acceptable studies are used as the relevant endpoint for
evaluating risk to various taxa. Implicit in the use of the lowest toxicity values for the most
sensitive species is the presumption that these toxicity values afford protection not only for the
individual surrogate species but for other untested taxa as well.

In the FIFRA risk characterization, data gaps are also considered as a source of uncertainty
in the risk assessment conclusions, and each risk assessment discusses the potential for additional
data to affect the risk assessment conclusions.

An additional source of uncertainty in assessing risk to aquatic life is the impacts of
multiple stressors on aquatic organisms. A United States Geological Survey (USGS) 10-year
study (Gilliom et al., 2006) shows that the most common form of pesticide exposure for aquatic
organisms is simultaneous exposure to multiple pesticides. More than 50 percent of all stream
samples contained five or more pesticides, although the majority of mixtures are comprised
mainly of agricultural herbicides and degradates of these herbicides, or urban/residential use
insecticides in urban streams. Pesticides that will be applied under the draft 2021 PGP may also
co-occur with other manmade contaminants and/or other pesticides from other uses. For instance,
the USGS has also performed monitoring studies which revealed the widespread presence of
some pharmaceuticals and personal care products in drinking water. However, although
pesticides may be detected with other chemicals or in discharges of pollutants covered by other

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NPDES permits, the majority of research and data on the effects of pesticides has focused on
individual pesticides rather than on additive and synergistic toxic effects of exposure to multiple
pesticides and/or non-pesticide toxicants.

Possible interactions among pesticides or between pesticides and other contaminants may
occur including: independent, additive, antagonistic, or synergistic. The variety of chemical
interactions presented in the available literature14 suggests that the interaction can be a function
of many factors including but not necessarily limited to: (1) the exposed species, (2) the co-
contaminants in the mixture, (3) the ratio of concentrations in the mixture, (4) differences in the
pattern and duration of exposure among contaminants, and (5) the differential effects of other
physical/chemical characteristics of the receiving waters (e.g., organic matter present in sediment
and suspended water). Quantitatively predicting the combined effects of all these variables on
mixture toxicity to any given taxon with confidence is beyond the capabilities of the available
data. In order to assess the impacts of environmental mixtures on aquatic life, states have
included ambient toxicity testing (also called Whole Effluent Toxicity or WET testing) in their
monitoring programs. WET testing allows states to identify potential impacts to aquatic life and
identify the toxicant(s) and through the toxicity reduction evaluation, reduce the source(s) of the
toxicant(s). The level of toxic effect to the most sensitive tested species is therefore assumed to
be protective of other species that may be present in any given water body and is assumed to
represent the most toxic component of a mixture. Note that a discussion of EPA's consideration
of WET testing as a condition of the permit is discussed in Part III.4 of the fact sheet.

Aquatic Benchmarks

EPA's Office of Pesticide Programs (OPP) derives aquatic benchmarks by multiplying the
most sensitive toxicity values (i.e., the lowest acceptable toxicity value for the most sensitive
species within a taxonomic group) by their respective (level of concern) LOC. These taxon-
specific benchmarks, based on toxicity data used by OPP in assessments for FIFRA pesticide
registration decision-making, are considered estimates of the concentrations below which
pesticides are not expected to have the potential for adverse effects for the particular taxon for
which those data serve as surrogates. It is reasonable to assume that above these levels, there
may be potential for the pesticide to cause adverse effects to the given taxon.

EPA's Office of Water (OW) and OPP agreed that these values can be used by States and
others to evaluate potential risks of pesticides in the aquatic environment, if a National
Recommended Water Quality Criterion for ambient water quality is not available.15 A number of
states have used these benchmark values as indicators of whether pesticide residues detected in
surface water warrant additional action such as refined monitoring efforts. While benchmarks
can be useful as a screening tool, they do not provide the information necessary to link detected
concentrations with their sources.

14 National Research Council 2013. Assessing Risks to Endangered and Threatened Species from
Pesticides. Washington, DC: The National Academies Press.

15 Correspondence to SFIREG, November 3, 2006 from Office of Water director.

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In response to recommendations and input from stakeholders, EPA developed a webpage
of non-regulatory "OPP Aquatic Benchmarks."16

As described above, EPA's FIFRA risk assessment process includes a number of
conservative assumptions that taken as a whole mitigate unreasonable ecological risk and protect
water quality.

(2) Examination of national-scale ambient monitoring data to assess whether pesticide
residues are currently present in waters at levels that would exceed water quality
standards.

Environmental Science and Technology: Pesticides in U.S. Streams and Rivers: Occurrence
and Trends during 1992—2011

In addition to the protective nature of the pesticide risk assessment, EPA reviewed readily
available surface-water monitoring data from the USGS National Water-Quality Assessment
(NAWQA) Project. In 2006, the USGS NAWQA17 released a 10-year (1992-2001) study of 51
major river basins and aquifer systems that account for more than 70 percent of total United
States water use, and more than 50 percent of the United States drinking water supply. During
the 2011 PGP development, EPA reviewed the data and found a total of 20 pesticides or
degradates exceeded an EPA benchmark in one or more agricultural stream and/or urban stream
(see the 2011 PGP, Appendix A of the fact sheet for a complete list of pesticides/degradates that
had exceedances). Since 2001, EPA noted that regulatory actions taken under FIFRA with
respect to all 20 pesticides found to be in excess of a benchmark, and many of their uses have
been canceled(several detections were of pesticides no longer in use prior to the start of the
study). See the 2011 PGP, Appendix C of the fact sheet for a summary of pesticide-specific
exceedance data and risk mitigation actions.

In 2014, the USGS NAWQA18 released a study of pesticide monitoring in streams and
rivers across the U.S. for the decade of 2002-2011 that compares monitoring data to previously
reported findings from the decade of 1992-2001. During the 2016 PGP development, EPA
reviewed this USGS second decadal report and noted the findings in the accompanied fact sheet.
As USGS has not released another similar report, for this PGP's fact sheet, EPA noted below the
findings from the last review and updated EPA's regulatory actions under FIFIRA. This report
indicated that with regard to chronic aquatic life benchmarks, during 1992 - 2001, 16 pesticides
exceeded a chronic aquatic life benchmark, while during 2002 - 2011, twenty-one pesticides
exceeded a chronic aquatic life benchmark. See Appendix A of the fact sheet. Forty-seven

16 OPP Aquatic Benchmark Table https://www.epa.gov/pesticide-science-and-assessing-pesticide-
risks/aauatic-life-benchmarks-pesticide-registration

17 Gilliom and others 2006. The Quality of Our Nation's Waters-Pesticides in the Nation's Streams and
Groundwater, 1992-2001: U.S. Geological Survey Circular 1291, 172p.

18 Stone and others 2014. An Overview Comparing Results From Two Decades of Monitoring for
Pesticides in the Nation's Streams and Rivers, 1992-2001 and 2002-2011. U.S. Geological Survey Scientific
Investigations Report 2014-5154, 23 p.

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pesticides were assessed in both decades. For 10 of these19 with benchmark exceedances in both
decades, exceedance frequencies were mostly lower during 2002 - 2011.20 21This research found
that that the proportion of assessed streams with one or more pesticides that exceeded a chronic
aquatic life benchmark were very similar between the two decades for agricultural (69% for 1992
- 2001 compared to 61% for 2002 - 2011) and mixed use streams (45% compared to 46%). For
urban streams the percentage increased from 53% during 1992 - 2001 to 90% during 2002 -
2011 predominantly due to the use of fipronil and dichlorvos in the latter decade (these two
pesticides are among those not assessed for 1992 - 2001). Additional detail on the nature of
EPA's regulatory actions under FIFRA appears in Appendices B and C of the fact sheet.

State Water Quality Monitoring under CWA

Every two years states must identify, based on ambient sampling, waterbodies that are not
attaining water quality standards (WQS; both narrative and numeric) under CWA Section
303(d). States must place waterbodies not meeting water quality standards on a list (303(d) list)
which identifies the pollutant or pollutants causing or expected to cause the impairment. The
Office of Water's Impaired Waters and Total Maximum Daily Loads website22 (accessed
February 2020) indicates 303(d) impairments in several states for 18 currently registered specific
pesticides and 4 general classes of pesticides (e.g., pyrethroids; Table 1). With the adoption of a
303 list, states are required to develop a Total Maximum Daily Load (TMDL). States also must
include a priority ranking for developing those TMDLs. A critical component in the TMDL
process is to identify the sources of each parameter for which the waterbody is listed. Then, the
State must develop waste load allocation(s) for point source(s) and load allocation(s) for
nonpoint source(s).

Table 1. Currently registered pesticide active ingredients listed as causes of 303(d) impairment

data accessed February 2020)

Cause of Impairment

States

Aldicarb

Atrazine

IL, KS, LA, MO, NE, OH

Bifenthrin

Carbaryl

Chlorpyrifos

CA, ID, MN, OK, OR, WA

Cypermethrin

Diazinon

CA, KS, OK, WA

Dichlorvos

19 Metolachlor, Atrazine, Diazinon, Malathion, Chlorpyrifos, Carbaryl, Azinphos methyl, cis-Permethrin,
Disulfoton, Parathion.

20 Stone and others 2014. Pesticides in U.S. Streams and Rivers: Occurrence and Trends during 1992-2011.
Environmental Science and Technology, 2014, 48, 11025-11030.

21 EPA notes that none of these 10 pesticides are among the top 10 solid or top 10 liquid or top 10
briquettes pesticide active ingredients applied under the draft 2021 PGP as reported in the 2018 annual report data.
Seven of these top ten 10 pesticides are biological pesticides.

22 http://iaspub.epa.gov/waterslO/attains nation cv.control?p report tvpe=T

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

Cause of Impairment

States

Dimethoate

Diuron

Malathion

CA, ID

Naphthalene

CA, NH, WA

Oxyfluorfen

Permethrin

Prometryn

Simazine

Trifluralin

Pesticides - listed generically

CA, IN, NY, OH, PA, PR

According to the Office of Water's Impaired Waters and Total Maximum Daily Loads
website there are a total of 72,667 causes of impairments for 303(d) listed waters23. Of these,
approximately 2.4% (a total of 1,774) are listed as pesticides. The majority (73.6% or 1,306 of
the 1,774) of impairments attributed to pesticides are for those no longer registered for use by
EPA. A total of 23% (415 of the 1,774) of impairments are attributed to currently registered
pesticides, with an additional 3% (53 of the 1,774) of the impairments listed generically for
pesticides, such as for "pesticides" or "organochlorine pesticides." Combined, these two
categories of listings account for 0.6% (468 of 72,667) of the total causes of impairments for
303(d) listed waters nationally. However, it is important to note that many states do not routinely
monitor for many currently registered pesticides. This is a source of uncertainty for this
assessment. Additionally, 4,741 impairments are listed for "impaired biota" and 1,209
impairments are for an "unknown" or "cause unknown - fish kills", which together account for
about 8%> of all impairments.

In developing the 2011 PGP, EPA received ambient monitoring data for pesticides present
in waters that are attributable to a variety of types of pesticide use patterns from states and other
stakeholders. These data are included in the administrative record for the 2011 permit (see
docket number EPA-HQ-OW-2010-0257) and in general, do not show the presence of pesticides
in concentrations above levels of concern (i.e., recommended ambient water quality criteria -
available at https://www.epa.gov/wqc/national-recommended-water-qualitv-criteria or FIFRA
OPP benchmark levels - available at https://www.epa.gov/pesticide-science-and-assessing-
pesticide-risks/aquatic-life-benchmarks-pesticide-registration).

23 http://iaspub.epa.gov/waterslO/attains nation cv.control?p report tvpe=T#causes 303d

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EPA has compared available CWA 303(d) impairment information regarding water quality
impairments caused by pesticides for states expected to be covered by the draft 2021 PGP with
active ingredient information submitted pursuant to the annual report requirements in the 2016
PGP. Annual report data for 2017-2019 was examined. EPA found that of the 17 pesticide active
ingredients identified on the relevant 303(d) lists as causes of water quality impairment, 7 of
these pesticides have been cancelled24 and others have significant restrictions. Based on annual
report data,25 none of the 303(d) impairments caused by pesticides in PGP states for the 303(d)
reported years were for pesticides applied under the PGP in those respective states.26

2017 National Water Quality Inventory Report

States, tribes, and territories are required to report biennially on the water quality of
navigable waters in their boundaries, and the extent to which these waters support designated
uses, under Section 305(b) of the Clean Water Act. In the report to Congress27, which was
submitted in August 2017, the Agency summarized the findings of four statistically
representative National Aquatic Resource Surveys and the site-specific assessment results
reported by the states in their Integrated 305(b)/303(d) Reports. States identified a wide range of
assessed waters as not fully supporting at least one of their designated uses. Mercury (primarily
in fish tissue), pathogens, nutrients, PCBs, sediment, and organic enrichment/oxygen depletion
were all cited as leading causes of impairment in assessed waters.

While pesticides are not always monitored when assessing water quality, the Report to
Congress indicated that pesticides were not among the most common causes of impairments
except for the Great Lakes shoreline. "States assessed 4,431 of the nation's 5,000 miles of Great
Lakes shoreline miles. Of these assessed miles, 4,353 were reported as impaired for one or more
designated use. The leading causes of impairment included PCBs, dioxins, and pesticides. The
leading probable sources of impairment were atmospheric deposition, legacy/historical pollution
- primarily contaminated sediment - and agriculture." The Report does not indicate whether any
impairments identified by the states were caused by discharges of pollutants that will be subject
to NPDES permits under the CWA.

24 DDE is also effectively cancelled with the cancellation of DDT.

25 Note that not all aquatic pesticide dischargers are required to submit annual reports. Annual reports are
required from decision-makers required to submit an NOI and who are large entities, and decision-makers with
discharges of pollutants to water containing NMFS listed resources of concern.

26 See sec. 1.1.2.1 of the draft 2021 PGP.

27 https://www.epa.gov/waterdata/2017-national-water-aualitv-inventorv-report-congress

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U.S. Environmental Protection Agency	Draft 2021 NPDES Pesticide General Permit Fact Sheet

Note: This document is aprepublication version, signed by all 10 U.S. EPA Regions on December 14, 2020. EPA is
submitting it for publication in the Federal Register. We have taken steps to ensure the accuracy of this version, but
it is not the official version.

Interpretation of Monitoring Data Relevant to the draft 2021 PGP

When re-evaluating the registrations of existing pesticides, the Agency considers available
surface-water monitoring data as a line of evidence regarding potential aquatic risk in addition to
considering exposure estimates derived from simulation models. Such monitoring data can
provide a measure of trends in aquatic exposure associated with mitigation measures imposed by
the Agency. For instance, the USGS's 2009 report of Trends of Pesticide Concentrations in
Corn-belt Streams states, "(t)he declines in pesticide concentrations closely followed declines in
their annual applications, indicating that reducing pesticide use is an effective and reliable
strategy for reducing pesticide contamination in streams." Similarly, a study entitled Trends in
pesticide concentrations and use for major rivers of the United States28 found that "pesticides
strongly dominated by agricultural use (cyanazine, alachlor, atrazine and its degradate
deethylatrazine, metolachlor, and carbofuran) has widespread agreement between concentration
trends and use trends" and that "pesticides with substantial use in both agricultural and
nonagricultural applications (simazine, chlorpyrifos, malathion, diazinon and carbaryl) had
concentration trends that were mostly explained by a combination of agricultural use trends,
regulatory changes, and urban use changes inferred from concentrations trends in urban
streams."

Monitoring studies are valuable because they may specifically target areas in which
pesticides considered in the study are likely to be used. This is an effective way of evaluating
impact from mitigation measures, or the increase in use of other pesticides that might replace
pesticides to which mitigation measures are applied.

The best way to interpret the likely causes of pesticide detections in surface water is to
consider any detection in light of the design of the monitoring study itself. For instance, the
USGS's study The Quality of Our Nation's Water - Pesticides in the Nation's Streams and
Ground Water, 1992-2007, described above, used a targeted approach, focusing on areas of
relatively homogenous land-use and environmental settings to relate pesticide occurrence to
individual non-point sources. The sampling was also most intensive during periods of high
pesticide use and runoff. Such a design can best capture transport of pesticide to surface water
from runoff from treated agricultural fields (or treated buildings/lawns) in a watershed. But, the
timing and location of sample collection may not be as effective in capturing residues of
pesticides applied for purposes covered under the General Permit. Concentrations detected could
at times reflect such uses, but the design of the study was meant to capture more diffuse non-
point transport of pesticides in watersheds, and not point source discharge.

Uncertainties with Monitoring Data

The Agency recognizes that monitoring of pesticide levels in water has limitations in its
ability to identify whether use of specific pesticide may adversely affect water quality. The
product monitoring data give only a "snapshot" of the concentration in a particular waterbody at
a particular time. While the USGS (Gilliom et al., 2006) intensified the frequency of its
monitoring during times of the year when most agricultural pesticide usage commonly occurred,

28 Ryberg and Gilliom, Science of the Total Environment 538 (2015) 431-444, Elsevier B.V.

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their sampling did not necessarily account for timing of specific pesticide applications, frequency
of applications, and meteorological events that can cause pesticides to reach surface water as
covered by this permit. Thus, monitoring may not collect a sample when pesticide concentrations
are at peak levels or when present in the water. Moreover, if monitoring detects the presence of a
pesticide, the data usually do not identify the source or if the pesticide residue is actually still a
product serving its intended purpose. Ambient monitoring cannot determine whether the
contamination was due to lawful use (and if so, which one) or unlawful pesticide use, an
accidental spill or discharge of pollutants, or whether the residues detected were from runoff, or
from aquatic uses such as those to be included in the NPDES general permit. Monitoring data are
often difficult to interpret because the ancillary data on pesticide usage in a basin, and factors
that could make the location more or less vulnerable, are often not available.

(3) Technology-based effluent limitations in the draft 2021 PGP provide further protections
beyond compliance with existing FIFRA requirements.

EPA has evaluated available information and expects that the technology-based effluent
limitations are as stringent as necessary to meet applicable WQS. These effluent limitations
require Operators to minimize the discharge of pollutants through the use of the most efficient
and effective means of Pest Management Measures, including pesticide and non-pesticide
methods.

The technology-based effluent limitations require Applicators to minimize the discharge of
pollutants by using only the amount of pesticide and frequency of pesticide application necessary
to control the target pest, maintaining pesticide application equipment in proper operating
condition, and ensuring weather conditions in the treatment area are appropriate for pesticide
application.

The Applicator, to the extent not determined by the Decision-maker, must also use only the
amount of pesticide and frequency of pesticide application necessary to control the target pest,
using equipment and application procedures appropriate for the task.

Certain Decision-makers are also required to more fully assess and implement procedures
to minimize the discharge of pollutants. In this assessment, these Decision-makers must consider
human health and ecological impacts, feasibility, and cost effectiveness and include prevention,
mechanical/physical methods, cultural methods, biological control agents, and as a final resort,
the application of pesticides. To ensure that pollutant discharges are minimized, these Decision-
makers must identify target pest species and areas where those pests occur, identify the possible
sources of the problem, and establish action thresholds or similar measures for implementing
pest management strategies. The technology-based effluent limitations in Part 2.2 of the draft
2021 PGP also require certain Decision-makers, as appropriate, to analyze surveillance data prior
to each pesticide application to determine when pest action thresholds are met.

The general permit includes several other provisions that the Agency expects to provide
further protections beyond compliance with FIFRA requirements. For instance, Part 4 of the
draft 2021 PGP requires Operators to monitor pesticide applications activities to minimize
discharges of pollutants and during any post-application monitoring to determine effectiveness of
the pesticide application. In addition, Part 6.0 of the draft 2021 PGP contains requirements for all

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

Operators to document and report adverse incidents involving non-target organisms or the
environment, and to take corrective action if it is determined that revising Pest Management
Measures can help to prevent future incidents. An adverse incident report calls attention to a
situation in which water quality may be impacted by pesticide use and may indicate that
corrective action is required to ensure that water quality standards are further protected during
future applications. The permit also requires Operators to take corrective actions to eliminate
other situations such as unauthorized releases (i.e., spills or leaks) or the failure to meet
applicable water quality standards. These requirements are discussed further in Part III.6 of the
fact sheet. EPA expects this approach will further reduce discharges of pollutants to waters of the
United States from the use patterns covered under this permit.

(4) Biological pesticides either do not work through a toxic mode of action, or when they
do, are toxic only to a very narrow range of target pest organisms. For chemical pesticides,
the discharges of pollutants covered under this permit are the residues after the pesticide
has performed its intended purpose.

The permit provides coverage for point source discharges of pollutants from certain
applications of pesticides, as identified in Part 1.1.1. of the draft 2021 PGP. Discharges of
pollutants from the application of both chemical and biological pesticides are covered under the
permit, consistent with the Sixth Circuit Court's reading of the CWA term "pollutant" in
National Cotton Council v. EPA.

For chemical or conventional pesticides applied directly to waters (e.g., for aquatic weed
control and aquatic nuisance pest control), it is the pesticide residue, including excess pesticide
that is present outside of the treatment area or within the treatment area once the target pests
have been controlled that is considered a pollutant under the draft 2021 PGP. For any pesticide
applied over water (e.g., mosquito control), any pesticide or pesticide residue that is incidentally
deposited in waters of the United States is considered a pollutant since the intended purpose of
the application is to target pests above the water. Therefore, the concentrations of "pollutants"
will be no higher, and in many instances significantly lower, than the product concentrations
considered in EPA's assessment when the Agency registered the pesticide products for the
relevant uses.

Discharges of biological pesticides require permit coverage regardless of whether or not a
residue exists. Biological pesticides or biopesticides are certain types of pesticides derived from
such natural materials as animals, plants, bacteria, and certain minerals. Two classes of
biopesticides are relevant to this permit, microbial pesticides and biochemical pesticides.
Microbial pesticides consist of a microorganism (e.g., a bacterium, fungus, virus, or protozoan)
as the active ingredient. The most widely used microbial pesticides are subspecies and strains of
Bacillus thuringiensis, or Bt which operate by a toxic mode of action, yet they are toxic only to a
very narrow range of target pest organisms (mosquito larvae). Biochemical pesticides, as defined
in 40 CFR 158.2000(a), are naturally occurring substances that control pests by non-toxic
mechanisms. Biochemical pesticides include substances, such as insect sex pheromones that
interfere with mating, as well as naturally-occurring repellants and attractants.

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U.S. Environmental Protection Agency	Draft 2021 NPDES Pesticide General Permit Fact Sheet

Note: This document is aprepublication version, signed by all 10 U.S. EPA Regions on December 14, 2020. EPA is
submitting it for publication in the Federal Register. We have taken steps to ensure the accuracy of this version, but
it is not the official version.

Biopesticides are usually inherently less toxic than conventional pesticides and generally
only affect the target pests and closely related organisms. Often, they are effective in very small
quantities and decompose quickly thereby resulting in lower exposures and largely avoiding the
pollution problems caused by chemical pesticides. When used as a component of Integrated Pest
Management (IPM) programs, biopesticides can greatly decrease the use of chemical pesticides;
however, use of biopesticides effectively requires users to have a very good understanding of
pest management. Since biochemical pesticides, by regulatory definition, do not work through a
toxic mode of action they may be less likely to result in an excursion of a water quality standard.

(5)	The draft 2021 PGP excludes with certain exceptions pesticide applications that result
in discharges of any pesticide to (1) waters impaired for an active ingredient in that
pesticide or a degradate of such active ingredient or (2) any Tier 3 waters Outstanding
National Resource Waters) except for applications made to restore or maintain water
quality or to protect public health or the environment that either do not degrade water
quality or only degrade water quality on a short-term or temporary basis.

EPA identified two scenarios where it finds the draft 2021 PGP may not be adequately
protective of water quality standards and has excluded those discharges of pollutants from
coverage under this draft 2021 PGP. Namely, the draft 2021 PGP excludes from coverage: (1)
any discharges from a pesticide application to waters of the United States if the water is
identified as impaired by a substance which either is an active ingredient in that pesticide or is a
degradate of such an active ingredient and (2) discharges of pollutants to Tier 3 Waters (i.e.,
Outstanding National Resource Waters) except for pesticide applications made to restore or
maintain water quality or to protect public health or the environment that either do not degrade
water quality or only degrade water quality on a short-term or temporary basis. Any Operator
desiring to discharge pollutants in either of these two scenarios is required to submit an
application for an NPDES individual permit. Links to lists of impaired waters and Tier 3 waters
is available at https://www.epa.gov/npdes/pesticide-permitting. Additional discussion of the
basis for these requirements is provided in Part III. 1.1.2 of the fact sheet.

(6)	EPA has no evidence in the record that implementation of the 2011 PGP and 2016 PGP
have resulted in documented water quality problems.

EPA has not received any adverse incident reports documenting water quality problems
under the 2011 PGP and 2016 PGP to date. EPA is also not aware of any negative public health
or environmental impact resulting from discharges of pollutants authorized for use under the
2011 PGP and 2016 PGP.

4. Site Monitoring

Monitoring is required in any NPDES permit to demonstrate compliance with the permit
conditions. Monitoring requirements apply from the time any authorized Operator begins
discharging pollutants under the draft 2021 PGP. These requirements are not tied to submission
of an NOI. There are a variety of monitoring methods that a "traditional" NPDES permit may
require, including end-of-pipe monitoring to show compliance with relevant water quality-based
and technology-based effluent limitations prior to discharging pollutants to a receiving
waterbody. Monitoring may also pertain to actions taken to ensure that record keeping or other

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permit control activities are being properly implemented. Water quality monitoring of receiving
streams is not typically required in NPDES permits unless it is required to determine among
other things, compliance with mixing zone dilution standards or some other special permit
condition.

Pursuant to CWA sections 308 and 402(a)(2), 40 CFR 122.43(a), and other applicable
implementing regulations, the following requirements have been included in the permit, as
discussed below. The monitoring requirements of the draft 2021 PGP are narrative and
demonstrate compliance with permit conditions by using currently established pesticide use
routines for monitoring pest control. For instance, the draft 2021 PGP requires routine visual
inspections (described below) to be conducted as part of the pest control activity and/or as part of
post-application pest surveillance, and calls for records of the pollutant discharge volume to be
kept. The monitoring requirements of the permit are reasonable measures of good pest
management practice that the conscientious Operator should be currently employing to ensure
environmental health and safety and optimal control of pest organisms.

Monitoring of pollutant discharges poses several challenges not generally encountered in
"traditional" NPDES permitting situations. For example, there is no "wastewater discharge" per
se from pesticide applications that is analogous to end-of-pipe discharges of pollutants. For
example, a manufacturing plant would typically direct its wastewater through a treatment system
to remove pollutants, and then would direct the effluent through a pipe into a receiving
waterbody. However, for chemical pesticide applications, at the time of application the pesticide
contains both the portion serving its intended purpose as well as the potential residual for which
monitoring data would be appropriate. Thus, monitoring the "outfall" in this case would merely
provide data on the amount of the product as applied (information already known through the
FIFRA registration process) and would be inappropriate to compare with any type of technology
based effluent limitation or water quality standard.

EPA considered requiring ambient water quality monitoring. However, EPA thinks that it
was infeasible for the following reasons:

1) Uncertainty: Ambient water quality monitoring would generally not be able to
distinguish whether the results were from the pesticide application for which
monitoring is being performed, or some other upstream source.

2) Lack of applicable measurable standards: Federal pesticide-specific ambient water
quality criteria do not exist at this time for the vast majority of constituents in the
products authorized for use under the draft 2021 PGP.

3) Safety and Accessibility: Pesticides, particularly those used for mosquito control and
forestry pest control, are often applied over waterbodies in remote areas, hazardous
terrain, and swamps that are either inaccessible or pose safety risks for the collection of
samples.

4) Difficulty of residue sampling for chemical pesticides: For chemical pesticides, the
"pollutant" regulated by this draft 2021 PGP is the residue that remains after the
pesticide has completed its activity, and it is this residue that would be the subject of
any water quality monitoring requirement. However, the point at which only "residue"
remains is not practically discernable at this time for all pesticides.

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

5) Usefulness of data: Some states have questioned the value of ambient water quality
monitoring data obtained from state permitting programs. The data generally showed
that water quality impacts were not occurring, and one state even discontinued the
requirement in revisions of its state permit.

Given the infeasibility of requiring ambient water quality data to demonstrate permit
compliance, EPA thinks that there are suitable alternative monitoring activities to determine
permit compliance, other than ambient water quality monitoring, for the draft 2021 PGP.

Additionally, in assessing the appropriateness of requiring ambient water quality
monitoring, EPA also considered Whole Effluent Toxicity (WET) testing as a possible option for
assessing Operator compliance with permit conditions; however, WET testing in an NPDES
permit program is best used to monitor whether an Operator's discharge of pollutants is toxic and
not whether a receiving stream (i.e., the ambient environment), that may be influenced by a
number of different discharges of pollutants from different Operators and different sources, is
toxic. In addition, WET testing would not indicate the actual source of the toxicity. If a
waterbody is found to be toxic or to contain pollutants above water quality standards, it can be
quite complex to identify the source of the toxicity, which may or may not actually be the
NPDES permittee performing the monitoring.

Thus, the monitoring program that EPA has developed for the draft 2021 PGP has been
tailored to accommodate the unique situations related to pesticide applications. Routine visual
monitoring is required in the draft 2021 PGP and can be used to determine if any pesticide use
practices may need to be revised to ensure that avoidable adverse impacts to the environment do
not occur (See Part III.4.2 of the fact sheet). Monitoring records required by those Operators who
submit NOIs will establish a history that may indicate if or when practices need to be
reconsidered. The monitoring requirements in the draft 2021 PGP remain unchanged from EPA's
2016 PGP.

4.1 Visual Monitoring Requirements for Pesticide Applicators

Visual monitoring assessments are required as a means of identifying, for example,
instances of detrimental impact to non-target organisms, disruption or degradation of wildlife
habitat, or the prevention of designated recreational or municipal uses of a waterbody that may
possibly be related to the Operator's use of pesticides in a given area. This requirement consists
of visually monitoring the area to and around where pesticides are applied for possible and
observable adverse incidents, such as unanticipated death or distress of non-target organisms and
disruption of wildlife habitat, recreational or municipal water use.

Visual monitoring assessments are required during the pesticide application when
feasibility and safety allow. Visual monitoring is not required during the course of pesticide
application when that application is performed in darkness as it would be infeasible for the
inspector to note adverse effects under these circumstances. Additionally, the following
scenarios often preclude visual monitoring during pesticide application:

1. Applications made from an aircraft

2. Applications made from a moving road vehicle when the Applicator is the driver

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U.S. Environmental Protection Agency Draft 2021 NPDES Pesticide General Permit Fact Sheet

3. Applications made from moving watercraft when the Applicator is the driver

4. Applications made from a moving off-road wheeled or tracked vehicle when the
Applicator is the driver.

4.2 Visual Monitoring Requirements for all Operators

Visual monitoring must also be conducted during any post-application surveillance, such as
to determine the efficacy of the pesticide application. Visual monitoring of this type is required
of all Operators but only if the Operator, be it the Applicator or the Decision-maker or both,
performs post application surveillance in the course of business. EPA expects that post-
application visual assessments are reasonably conducted on foot or from a stationary vehicle,
although they might also be conducted from a moving vehicle, including a boat or plane, in
certain circumstances.

5. Pesticide Discharge Management Plan (PDMP)

Any Decision-maker who is or will be required to submit an NOI and is not a small entity29
must develop a PDMP, except for any pesticide applications made in response to a Declared Pest
Emergency situation, as defined in Appendix A of the draft 2021 PGP or any Decision-maker
who is or will be required to submit an NOI solely because of discharges of pollutants to waters
of the United States containing NMFS Listed Resources of Concern, as defined in Appendix A
of the draft 2021 PGP. EPA defines a Decision-maker that is not a small entity as a large entity
in the permit. Large entity Decision-makers must prepare the PDMP by the time the NOI is filed.

Any Decision-maker who is or will be required to submit an NOI and is a small entity {i.e.,
is below the Small Business Association (SBA) size standard, as defined in 13 CFR. 121.201, or
is a public entity serving a population of 10,000 or less), is not required to develop a PDMP.
Small entity Decision-makers are required to document activities as described in Part III.7.3 of
the fact sheet. EPA recognizes that the SBA defines "small entities" as including government
entities that serve populations of less than 50,000 persons. However, EPA's NPDES program has
historically considered "major" municipal NPDES permits as those that serve greater than
10,000 persons {i.e., with a wastewater treatment plant design of greater than one million gallons
a day). 'Major NPDES' permittees have increased recordkeeping and public notice obligations
over 'minor NPDES,' which is consistent with EPA's intent for the draft 2021 PGP to impose
additional recordkeeping and reporting information only on these larger communities.

The PDMP itself does not contain effluent limitations; rather it constitutes a tool both to
assist the Decision-maker in documenting what pest management measures it is implementing to
meet the effluent limitations, and to assist the permitting/compliance authority in determining
whether the effluent limitations are being met. Developing a PDMP helps Decision-makers
ensure they have (1) taken steps to identify the pest problem, (2) evaluated pest management
options, and (3) selected appropriate pest management measures to control pollutant discharges.
A PDMP is a "living" document that requires reviews and must be kept up-to-date. Where pest
management measures are modified or replaced to meet effluent limitations, such as in response

29 A small entity is any (1) private enterprise that does not exceed the Small Business Administration size
standard as identified at 13 CFR 121.201, or (2) local government that serves a population of 10,000 or less.

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to a Part 6.1 triggering condition in the draft 2021 PGP, such changes must be documented in the
PDMP. All changes to the PDMP must be made before the next pesticide application that results
in a discharge of pollutants, if practicable, or if not, no later than 90 days after any change in
pesticide application activities. Failure of a Decision-maker to develop and maintain an up-to-
date PDMP is a violation of the draft 2021 PGP. This recordkeeping violation is separate and
distinct from a violation of any of the other substantive requirements in the permit (e.g., effluent
limitations, corrective action, monitoring, reporting, and state-specific requirements).

A PDMP must include identification of the pesticide discharge management team, a
description of the pest problem, and a description of the pest management options evaluation.
Decision-makers must also provide response procedures for spill response and adverse incident
response. The size of a pest management area is determined by the Decision-maker responsible
for and with the authority to conduct pest management activities. For example, the pest
management area for a mosquito control district is the total area of the district. Once the plan is
developed, the Decision-maker must maintain the plan thereafter for the duration of coverage
under this general permit. For any Decision-maker for which the annual treatment area threshold
triggers the NOI requirement (and the Decision-maker is a large entity), the Decision-maker
must keep the plan up-to-date for the duration of permit coverage even if the annual treatment
area subsequently falls below the annual treatment area threshold.

Decision-makers may choose to reference other documents, such as a pre-existing pest
management plan or spill prevention and response plan, in the PDMP rather than recreating the
same text in the PDMP. It is not required that a Decision-maker must have authored the pre-
existing plan in order to use it. When referencing other documents, the Decision-maker is
responsible for ensuring his/her PDMP and the other documents together contain all the
necessary elements for a complete PDMP, as specified in Part 5.1 of the draft 2021 PGP. In
addition, the Decision-maker must ensure that a copy of relevant portions of those referenced
documents is attached to the PDMP and is located on-site and it is available for review,
consistent with Part 5.3 of the draft 2021 PGP.

5.1 Contents of the PDMP

The PDMP prepared under the draft 2021 PGP must meet specific requirements under Part
5.1 of the draft 2021 PGP. Generally, Decision-makers must document the following: (1) a
pesticide discharge management team; (2) a description of the pest management area and the pest
problem; (3) a description of pest management options evaluation; (4) response procedures for
spill response and adverse incident response; and (5) any eligibility considerations under other
federal laws.

Pesticide Discharge Management Team

The draft 2021 PGP requires that a qualified individual or team of individuals be identified
to manage pollutant discharges covered under the permit. Identification of a pesticide discharge
management team ensures that appropriate persons (or positions) are identified as necessary for
developing and implementing the plan. Inclusion of the team in the plan provides notice to staff
and management (i.e., those responsible for signing and certifying the plan) of the

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responsibilities of certain key staff for following through on compliance with the permit's
conditions and limits.

The pesticide discharge management team is responsible for developing and revising the
PDMP, implementing and maintaining the Pest Management Measures to meet effluent
limitations, and taking corrective action where necessary. Team members should be chosen for
their expertise in the relevant areas to ensure that all aspects of pest management are considered
in developing the plan. The PDMP must clearly describe the responsibilities of each team
member to ensure that each aspect of the PDMP is addressed. EPA expects most Decision-
makers will have more than one individual on the team, except for those with relatively simple
plans and/or staff limitations. The draft 2021 PGP requires that team members have ready access
to any applicable portions of the PDMP and the permit.

Problem Identification

This section includes the pest problem description, action threshold(s), a general location
map, and water quality standards.

1. Pest Problem Description.

The draft 2021 PGP requires that the PDMP include a description of the pest problem at the
pest management area. A detailed pest management area description assists Decision-makers in
subsequent efforts to identify and set priorities for the evaluation and selection of Pest
Management Measures taken to meet effluent limitations set forth in Parts 2 and 3 of the draft
2021 PGP and in identifying necessary changes in pest management. The description must
include identification of the target pest(s), source of the pest problem, and source of data used to
identify the problem. The draft 2021 PGP allows use of historical data or other available data
(e.g., from another similar site) to identify the problem at your site. If you use other site data, you
must document in this section why data from your site is not available or not taken within the
past year and explain why the data is relevant to your site. Additionally, the pest management
area descriptions should include any sensitive resources in the area, such as unique habitat areas,
rare or listed species, or other species of concern that may limit pest management options.

2. Action Threshold(s)

The draft 2021 PGP requires that the PDMP include a description of the action threshold(s)
established for the target pest, including a description of how they were determined and
method(s) to determine when the action threshold(s) has been met. An action threshold is a level
of pest prevalence (or other indicator) at which an Operator takes action to reduce the pest
population.

3. General Location Map

The PDMP must also contain a general location map of the site that identifies the
geographic boundaries of the area to which the plan applies and location of the waters of the
United States. To improve readability of the map, some detailed information may be kept as an
attachment to the site map and pictures may be included as deemed appropriate.

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4. Water Quality Standards

Operators must identify any Tier 3 Waters (Outstanding National Resource Waters) and
any water(s) impaired for a specific pesticide or its degradates to which there may be a discharge
of pollutants. Internet links to all state, territory and tribal water quality standards are available
at: http://www.epa.gov/wqs-tech.

Description of Pest Management Measures Options Evaluation

The draft 2021 PGP requires that the PDMP include a description of the Pest Management
Measures implemented to meet the applicable technology-based or water quality-based effluent
limitations. The description must include a brief explanation of the Pest Management Measures
used at the site to reduce pollutant discharge, including evaluation and implementation of the six
management options (no action, prevention, mechanical/physical methods, cultural methods,
biological control agents, and pesticides). Decision-makers must consider impact to non-target
organisms, impact to water quality, feasibility, and cost effectiveness when evaluating and
selecting the most efficient and effective means of Pest Management Measures to minimize
pollutant discharge to waters of the United States.

All six management options may not be available for a specific use category and/or
treatment area. However, the PDMP must include documentation of how the six management
options, including combination of these options, were evaluated prior to selecting site specific
Pest Management Measures. For the no action option, Operators should document the impact of
this option without any current Pest Management Measures at the site. For the prevention
management option, the Decision-maker should document the methods implemented to prevent
new introductions or the spread of the pests to new sites, such as identifying routes of invasion
and how these can be intercepted to reduce the chance of invasion. Prevention may include
source reduction, using pathogen-free or weed-free seeds or fill; exclusion methods (e.g.,
barriers) and/or sanitation methods, like wash stations, to prevent reintroduction by vehicles,
personnel, etc. Some prevention management methods may fall under mechanical/physical or
cultural methods, as well.

For the pesticide management option, Decision-makers may include a list of active
ingredient(s) evaluated. Discussion may also identify specific equipment or methods that will
prevent or reduce the risks to non-target organisms and pollutant discharges to waters of the
United States.

Response Procedures

The following procedures necessary to minimize discharges of pollutants must be documented in
the PDMP:

1. Spill Response Procedures

The PDMP must document procedures for expeditiously stopping, containing, and cleaning
up leaks, spills, and other release. In addition, the PDMP must include documentation of the
procedures for notification of appropriate facility personnel, emergency response agencies, and
regulatory agencies.

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2. Adverse Incident Response Procedures

In the PDMP, Decision-makers must document appropriate procedures for responding to an
adverse incident resulting from pesticide applications. Decision-makers must identify and
document the following:

- Procedures for responding to any adverse incident resulting from pesticide applications;

- Procedures for notification of the adverse incident, both internal to the Decision-
maker's agency/organization and external;

- State/Federal permitting agency contacts with phone numbers;

- Name, location, and telephone of nearest emergency medical facility; and

- Name, location, and telephone of nearest hazardous chemical responder (including
police and fire department).

Documentation to Support Eligibility Considerations under other Federal Laws

Decision-makers must keep, with the PDMP, documentation supporting their determination
with regard to Part 1.1.2.4 of the draft 2021 PGP (Endangered and Threatened Species and
Critical Habitat Protection).

Signature Requirements

The PDMP must be signed and certified in accordance with the signatory requirements in
the Standard Permit Conditions part of the draft 2021 PGP (Appendix B, 40 CFR 122.41(k)
Signatory requirement). This requirement is consistent with standard NPDES permit conditions
described in 40 CFR 122.22 and is intended to ensure that the Decision-maker understands
his/her responsibility to create and maintain a complete and accurate PDMP. The signature
requirement includes an acknowledgment that there are significant penalties for submitting false
information.

5.2 Pesticide Discharge Management Plan Modifications.

The draft 2021 PGP requires that the PDMP be updated whenever any of the triggering
conditions for corrective action in Part 6.1 of the draft 2021 PGP occur, or when a review
following the triggering conditions in Part 6.1 requires the Operator to revise his/her Pest
Management Measures as necessary to meet the effluent limitations in the draft 2021 PGP
(Part 2). Keeping the PDMP up-to-date will help the Decision-maker ensure that the condition
that triggered the corrective action does not reoccur. All changes to the PDMP must be made
before the next pesticide application that results in a discharge of pollutants, if practicable, or if
not, no later than 90 days after any change in pesticide application activities or after an annual
review.

It is important to note that failure to update the PDMP in accordance with Part 5.2 of the
draft 2021 PGP is a recordkeeping violation, not a violation of an effluent limit. For example, if
the Decision-maker changes its spill response procedures but fails to update its PDMP to reflect
these changes, a recordkeeping violation will result. The Decision-maker must revise its PDMP
to reflect the new procedures and include documentation of the corrective action (in accordance
with Part 6 of the draft 2021 PGP) to return to full compliance.

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5.3 Pesticide Discharge Management Plan Availability.

The draft 2021 PGP requires that a copy of the current PDMP, along with all supporting
maps and documents, be kept at the address provided on the NOI. The PDMP and all supporting
documents must be immediately available to representatives of EPA, a state, tribal, or local
agency governing pesticide applications, as well as representatives of the United States Fish and
Wildlife Service (USFWS) or the National Marine Fisheries Service (NMFS) at the time of an
on-site inspection or upon request. This requirement is consistent with standard NPDES permit
conditions described in 40 CFR 122.41. Part 5.3 of the draft 2021 PGP indicates that EPA may
provide access to portions of your PDMP to a member of the public upon request. Confidential
Business Information (CBI) may be withheld from the public, but consistent with 40 CFR Part 2,
may not be withheld from EPA or the Services.

6. Corrective Action

The purpose of including corrective action requirements in the draft 2021 PGP is to assist
this universe of NPDES permittees with effectively meeting technology-based and water-quality-
based effluent limitations and implementing Pest Management Measures in the draft 2021 PGP.
Corrective action requirements apply from the time any authorized Operator begins discharging
pollutants under the draft 2021 PGP. These requirements are not tied to submission of an NOI.
Corrective actions in this permit are follow-up actions an Operator must take to assess and
correct problems. They require review and revision of Pest Management Measures and pesticide
application activities, as necessary, to ensure that these problems are eliminated and will not be
repeated in the future. The draft 2021 PGP makes clear that the Operator is expected to assess
why a specific problem has occurred and document what steps were taken to eliminate the
problem. This approach will help Operators in complying with the requirements of the permit on
a consistent basis. Compliance issues with some of the permit's requirements — for instance,
those related to reporting and recordkeeping and some of those related to operation and
maintenance — may be able to be corrected immediately simply by following already established
procedures, and therefore, are not considered problems that trigger the corrective action
provisions of the draft 2021 PGP.

It should be noted that a situation triggering corrective action is not necessarily a permit
violation and, as such, may not necessarily trigger a modification of Pest Management Measures
to meet effluent limitations. However, failure to conduct (and document) corrective action
reviews in such cases does constitute a permit violation.

6.1 Situations Requiring Revision of Pest Management Measures

Operators are required to review and, as necessary, revise the selection and implementation
of their Pest Management Measures to eliminate any of the following situations:

- An unauthorized release or discharge of pollutants associated with the application of
pesticides (e.g., spill, leak, or discharge not authorized by this or another NPDES
permit) occurs;

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it is not the official version.

-	Operators become aware, or EPA concludes, that Pest Management Measures are not
adequate/sufficient for the discharge of pollutants to meet applicable water quality
standards;

-	Any monitoring activities indicate failure to meet applicable technology-based effluent
limitations in Part 2 of the draft 2021 PGP;

-	An inspection or evaluation by an EPA official, or local, state, or Tribal entity,
determines that modifications are necessary to meet the non-numeric effluent
limitations detailed in Part 2 of the draft 2021 PGP; or

-	An Operator observes or is otherwise made aware (e.g., a third-party notification) of an
adverse incident.

EPA considers the above situations to be of significant concern. Thus, EPA is requiring
Operators to assess the cause of these situations, which may be affiliated with the Operator's
discharge from the application of pesticides and to take any necessary steps to eliminate the
situation and ensure that the situation will not be repeated in the future.

The purpose of Part 6.1 of the draft 2021 PGP is to ensure compliance with corrective
action requirements through increased accountability and oversight. EPA views ongoing
assessment of the effectiveness of Pest Management Measures and corrective actions as integral
to an effective pesticide management program. Written records associated with corrective action
assessments must be kept with the other recordkeeping documentation required by this permit.

6.2	Corrective Action Deadlines

The draft 2021 PGP requires that corrective action be completed "before or, if not
practicable, as soon as possible after the next pesticide application that results in a discharge."
EPA emphasizes that this timeframe is not a grace period within which an Operator is relieved of
any liability for a permit violation. EPA is adopting this flexible deadline to account for the
variation in types of responses (e.g., evaluate situation and select, design, install, and implement
new or modified Pest Management Measures) that may be necessary to address any identified
situations of concern. EPA recognizes that in rare cases a corrective action review may identify
the need for substantial improvements to the Operator's Pest Management Measures and does
not want to limit the selection and implementation of such controls with an inflexible deadline.
Another possibility is that EPA or the Operator may determine that further monitoring is needed
under Part 6.3 of the draft 2021 PGP to pinpoint the source of the problem, and this monitoring
may need to be conducted during future pesticide application activities. In the vast majority of
cases, however, corrective action reviews will identify responses that can be taken quickly, either
before the next pesticide application that results in a discharge or shortly thereafter.

6.3	Effect of Corrective Action

The occurrence of a situation described in Part 6.1 of the draft 2021 PGP may, but does not
necessarily, constitute a violation of the draft 2021 PGP. The occurrence of a situation identified
in Part 6.1 does require the Operator to immediately review and as necessary, revise the selection
and implementation of their Pest Management Measures to eliminate the situation. Part 6.3 of the
draft 2021 PGP explains that taking corrective action does not absolve the Operator of any
liability for a permit violation requiring that action, however, failure to take required corrective

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action will constitute an original or an additional permit violation. EPA will consider the
appropriateness and promptness of corrective action in determining enforcement responses to
permit violations. EPA may impose additional requirements and schedules of compliance,
including requirements to submit additional information concerning the condition(s) triggering
corrective action, additional site-specific water-quality based limitations, additional monitoring
requirements, or other schedules and requirements more stringent than specified in this permit.
Those requirements and schedules will supersede those of Parts 6.1 and 6.2 of the draft 2021
PGP if such requirements conflict.

6.4 Adverse Incident Documentation and Reporting

Part 6.4 of the draft 2021 PGP requires Operators to take specific actions in response to
identified adverse incidents which may have resulted from a discharge from the Operator's
pesticide application. Namely, Operators are required to provide oral notice to EPA within 24
hours and then follow-up with a written report within 30 days of becoming aware of the adverse
incident. EPA defines an "adverse incident" in Appendix A of the draft 2021 PGP, but generally
it is defined as any effect of a pesticide's use that is unexpected or unintended, in which there is
evidence that a person or non-target organism has likely been exposed to a pesticide residue and
suffered a toxic or adverse effect.

Part 6.4.1 of the draft 2021 PGP requires Operators to call the appropriate EPA Incident
Reporting Contact within 24 hours of any identified adverse incident and provide basic
information about it. The purpose of this requirement is twofold: (1) to provide an opportunity
for the Agency to respond to these incidents as soon as reasonably can be expected, and (2) to
provide a basis for potential corrective actions. EPA does not expect this initial notification to be
detailed but merely a reporting of the date of the finding, a general discussion of the incident and
a review of the necessity to conduct corrective action. The draft 2021 PGP requires Operators to
document the information identified in Part 6.4.1, including the date and time that EPA was
notified and a description of any deviations from Part 6.4.1 notification requirements based on
nuances of the adverse incident. For example, an Operator may decide to notify multiple EPA
contacts because of the severity of the adverse incident. This type of information should be
included in the written documentation of the 24-hour notification as described below.

Part 6.4.2 of the draft 2021 PGP requires Operators to provide a written report of the
adverse incident to the appropriate EPA Regional office and to the State Lead Agency for
pesticide regulation within 30 days of discovering the adverse incident. The adverse incident
report must include the following information:

- Information required to be provided in Part 6.4.1.1 of the draft 2021 PGP;

- Date and time you contacted EPA notifying the Agency of the adverse incident;

- Location of incident, including the names of any waters affected and appearance of
those waters (sheen, color, clarity, etc.);

- A description of the circumstances of the incident including species affected, number of
individuals and approximate size of dead or distressed organisms;

- Magnitude of the effect (e.g., aquatic square area or total stream distance affected);

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it is not the official version.

-	Quantity of pesticide applied and EPA registration number of pesticide product,
intended use site (e.g., banks, above, or direct to water), and method of application;

-	Description of the habitat and the circumstances under which the incident occurred
(including any available ambient water data for pesticides applied);

-	Information on any laboratory tests performed and test results; and

-	Actions to be taken to prevent recurrence of the incident.

Adverse incident information associated with discharges from the application of pesticides
is useful to the Agency because the information:

-	Provides the Agency with an indication of the effectiveness of the permit in controlling
discharges of pollutants to protect water quality, including data upon which the Agency
may base future permit decisions (e.g., modifications to or reissuance of this permit).

-	May be considered when reviewing applications for registration of new pesticides that
are chemically similar to existing pesticides, as well as re-evaluations of existing
pesticides;

-	May be considered in ecological risk assessment and during deliberations on risk
management decisions;

-	May be reviewed to determine trends that may indicate potential ecological impacts
with an existing pesticide and/or to track improvements when mitigation measures are
applied;

-	Provides information on the nature, extent, and severity of incidents to decision-
makers, stakeholders, and the public; and

-	Provides the Agency with information on which to assess compliance with regulatory
requirements, including documentation and reporting.

Currently, there is no database that includes adverse reporting from anyone other than the
registrant under 6(a)(2) of FIFRA. EPA does not consider inclusion of adverse incident reporting
in the NPDES permit to be a duplicative requirement to the FIFRA section 6(a)(2) requirements
for registrant reporting of adverse incidents. This is because pesticide registrants are not likely to
be directly covered under the draft 2021 PGP. Although some pesticide product labels may
require that adverse incidents be reported, requiring the reporting of all adverse incidents and
follow-up corrective actions may address the lack of a universal, mandatory legal duty for
pesticide users to report adverse incidents, at least for the pesticide use patterns covered by the
draft 2021 PGP.

EPA acknowledges that assessing and correcting adverse incidents may be complicated in
certain instances. For example, symptoms associated with adverse incidents are often vague or
mimic other causes which may lead to incorrect diagnoses. Thus, it may be difficult to identify
and track chronic effects resulting from pollutant discharges. It may also be difficult to observe
adverse effects because of limited visibility or access such as dead fish poisoned in a wetland
under dense vegetation or in sparsely populated areas or because scavengers scatter or devour
carcasses before discovery. It is important, however, to identify to the extent feasible situations
where adverse effects occur where discharges from the application of pesticides also occur.

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it is not the official version.

Immediately observable signs of distress or damage to non-target plants, animals and other
macro-organisms within the treatment area may warrant concern for a possible adverse incident
related to a discharge of pesticides during application. EPA acknowledges that some degree of
detrimental impact to non-target species may occur and may be acceptable during the course of
normal pesticide application. EPA expects Operators to use their best professional judgment in
determining the extent to which non-target effects appear to be abnormal or indicative of an
unforeseen problem associated with an application of pesticides.

During a visual inspection, Operators should watch for distressed or dead juvenile and
small fish, washed up or floating fish, fish swimming abnormally or erratically, fish lying
lethargically at the water surface or in shallow water, fish that are listless or nonresponsive to
disturbance, the stunting, wilting, or desiccation of non-target submerged or emergent aquatic
plants, and other dead or visibly distressed non-target organisms including amphibians, turtles,
and macro-invertebrates. These observations must be noted unless they are deemed not to be
aberrant (for example, distressed non-target fish are to be expected when conducting pest control
with rotenone and non-target vegetation will be stressed near the target of contact herbicides). It
should be noted that observation of these impacts does not necessarily imply that a pesticide has
been misused or that there has been a permit violation or an instance of noncompliance, but may
provide cause for further investigation of local water quality or reconsideration of Pest
Management Measures.

Complete information concerning adverse impacts will aid EPA in any review of current or
future pesticide use, adherence to Pest Management Measures, or effectiveness of these
measures. Reporting of adverse incidents is not required under this permit in the following
situations: (1) you are aware of facts that indicate that the adverse incident was not related to
toxic effects or exposure from the pesticide application; (2) you have been notified in writing by
EPA that the reporting requirement has been waived for this incident or category of incidents;
(3) you receive information notifying you of an adverse incident but that information is clearly
erroneous; (4) an adverse incident occurs to pests that are similar in kind to pests identified as
potential targets on the FIFRA label. However, even for these situations, certain records must be
kept on site by those Decision-makers who are required to submit NOIs, pursuant to Part 7.3 and

7.4	of the draft 2021 PGP.

6.5	Reportable Spills and Leaks

Part 6.5.1 of the draft 2021 PGP requires Operators to call the appropriate EPA Incident
Reporting Contact to report any spill or leak of a hazardous substance or oil into waters of the
United States with 24 hours of becoming aware of the spill or leak.30 Part 6.5.2 of the draft 2021
PGP requires Operators to document this notification within 30 days of becoming aware of such
spill or leak. If the spill or leak triggers the notification in Part 6.5.1 and results in an adverse
incident, then Operators must report the incident per the guidelines in Part 6.4.1 and 6.4.2 of the
draft 2021 PGP. If the spill or leak triggers the notification in Part 6.5.1, but does not result in an
adverse incident, then Operators must document and retain information outlined in Part 6.5.2

30 Reportable Spills and Leaks are defined as those that trigger the requirement to notify the National
Response Center (40 CFR Parts 110, 117, 302) based on the type of pollutant and quantity released.

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within 30 days of becoming aware of the situation. This documentation provides a written record
of what you reported to EPA orally. It should also include a description of the reporting system
that will be used to alert responsible managers and legal authorities in the event of a future spill
or leak and a description of preventive measures to prevent, contain, or treat spills and leaks of
these materials. Part 6.4.3 of the draft 2021 PGP requires Operators to notify either the National
Marine Fisheries Service or the United States Fish and Wildlife Service if the Operator becomes
aware of an incident that may have resulted from a discharge from the pesticide application that
adversely affects a federally-listed threatened or endangered species or its federally-designated
critical habitat. This information will be used by EPA to ascertain compliance with permit
conditions.

6.6 Documentation for Other Corrective Action

For any event described in Part 6.1 of the draft 2021 PGP, other than for adverse incidents
or reportable spills or leaks, immediate reporting to EPA is not required, but Operators must
document basic information describing the event and the Operators' response to that event within
30 days. For triggering events in Part 6.1, where the Operator determines that revision to Pest
Management Measures is not necessary, the Operator must still document the review and the
basis for this determination. EPA is not requiring Operators to submit this documentation to the
Agency. Rather, EPA expects Operators to retain this information on-site and upon request, to
make any such records available to EPA or any other Federal, state, or local regulatory agency
governing pesticide applications. A summary of this information must also be included in the
annual report for Operators subject to the annual reporting requirement.

7. Recordkeeping and Annual Reporting

The draft 2021 PGP requires all Decision-makers and Applicators to maintain certain
records to help them assess performance of Pest Management Measures and to document
compliance with permit conditions. Recordkeeping and reporting requirements apply from the
time any authorized Operator begins discharging pollutants under the draft 2021 PGP. These
requirements are consistent with Federal regulations at 40 CFR 122.41(j), but have been tailored
to more closely reflect the requirements in the PGP. The draft 2021 PGP requires a basic set of
records to be maintained by all Decision-makers and Applicators, as well as separate
requirements depending on the type of Operator (i.e., Applicator, For-Hire Applicators, NOI
submitting Decision-maker who is a small entity and NOI submitting Decision-maker who is a
large entity). Part 7 of the draft 2021 PGP sets forth the recordkeeping requirements for each of
these types of Operators. Operators can rely on records and documents developed for other
programs, such as requirements under FIFRA, provided all requirements of the permit are
satisfied.

EPA has found that it is appropriate and reasonable to require different records for different
types of Operators, reasoning that the recordkeeping responsibilities assigned in the permit
reflect the nature of involvement in pesticide application activities for the Operators described.
The following sections describe the sets of records that the draft 2021 PGP requires different
types of Operators keep and enumerates the specific information items to be recorded.

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it is not the official version.

7.1	Records to be Kept by all Operators (all Decision-makers and all Applicators)

These records must be kept by all Operators, including those not submitting an NOI.
Although this section is a universal requirement, these particular records are necessary only in
the event of an adverse incident, the case that corrective action was required, or in the event of a
discharge resulting from a spill or leak.

a.	A copy of any Adverse Incident Reports (See Part 6.4.2);

b.	Rationale for any determination that reporting of an identified adverse incident is not
required, consistent with allowances identified in Part 6.4.1.2;

c.	A copy of any corrective action documentation (See Part 6.6); and,

d.	A copy of any spill and leak or other unpermitted discharge of pollutants
documentation (See Part. 6.5.2)

7.2	Records to be Kept by all For-Hire Applicators

All Operators who are For-Hire Applicators, as defined in Appendix A of the draft 2021
PGP, must keep the records listed above, as well as records that specifically document pesticide
application equipment maintenance and details of the pesticide application event. Since
Decision-makers who are not themselves performing pesticide applications are generally not able
to record such information, EPA requires different recordkeeping requirements depending on the
type of Operator.

a.	Documentation of equipment calibration; and

b.	Information on each treatment area to which pesticides are discharged, including:

1.	Description of each treatment area, including location and size (acres or linear feet)
of treatment area and identification of any waters, either by name or by location, to
which pesticide(s) are discharged;

2.	Pesticide use pattern(s) {i.e., mosquito and other flying insects, weed and algae,
animal pest, or forest canopy);

3.	Target pest(s);

4.	Documentation of any assessment of weather conditions in the treatment area prior
to and during application to ensure application is consistent with all applicable
federal requirements;

5.	Name of each pesticide product used including the EPA registration number;

6.	Quantity of each pesticide product applied to each treatment area;

7.	Pesticide application date(s); and

8.	Whether or not visual monitoring was conducted during pesticide application and/or
post-application and if not, why not and whether any unusual or unexpected effects
identified to non-target organisms.

7.3	Records to be Kept by Small Entities, Submitting an NOI

As mentioned in Part 5, any Decision-maker that is required to submit an NOI and is below
the SBA thresholds for small businesses or is a public entity serving a population of fewer than
10,000, is defined as a small entity in the permit. Small entities are required to keep a basic

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it is not the official version.

records set, outlined in Part 7.3 of the draft 2021 PGP, all of which can be recorded on the
Pesticide Discharge Evaluation Worksheet provided in the draft 2021 PGP Appendix F.

Decision-makers who are required to submit an NOI and who are defined as small entities
(as identified in Part 5) are required to keep the following records at the address provided on the
NOI, as identified in Part 1.2.2 of the draft 2021 PGP. A worksheet for documenting this
information on each treatment area is provided in Appendix F of the draft 2021 PGP, Pesticide
Discharge Evaluation Worksheet.

a.	Copy of the NOI submitted to EPA, any correspondence exchanged between the
Decision-maker and EPA specific to coverage under this permit, and a copy of the EPA
acknowledgment letter with the assigned permit tracking number;

b.	Documentation of equipment calibration (only if Decision-maker is also the
Applicator);

c.	Information on each treatment area to which pesticides are discharged, including:

1.	Description of treatment area, including location and size (acres or linear feet) of
treatment area and identification of any waters of the United States, either by name
or by location, to which pesticide(s) are discharged;

2.	Pesticide use pattern(s) (i.e., mosquito and other flying insects, weed and algae,
animal pest, or forest canopy);

3.	Target pest(s) and explanation of need for pest control;

4.	Description of pest management measure(s) implemented prior to the first pesticide
application;

5.	Company name and contact information for pesticide applicator;

6.	Name of each pesticide product used including the EPA registration number;

7.	Quantity of each pesticide product applied to each treatment area;

8.	Pesticide Application Start Date;

9.	Pesticide Application End Date; and

10.	Whether or not visual monitoring was conducted during pesticide application and/or
post-application and if not, why not and whether any unusual or unexpected effects
identified to non-target organisms.

7.4 Records to be Kept by Large Entities, Submitting an NOI

Any Decision-maker who is required to submit an NOI and is above the Small Business
Administration (SB A) threshold for a small business or a public entity who serves a population
of 10,000 or more is defined as a large entity in the permit. Large entities are required to keep
the records listed in Part 7.4 of the draft 2021 PGP. EPA expects that large entities will have a
greater capability than small entities to record specific details of the pest treatment area, and is
therefore requiring slightly more comprehensive recordkeeping. In addition, much of the records
set for large entities are reflected in the annual report that these entities must submit. The
reported information will allow EPA to better characterize the discharges resulting from
pesticide applications in a variety of different circumstances.

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Note: This document is aprepublication version, signed by all 10 U.S. EPA Regions on December 14, 2020. EPA is
submitting it for publication in the Federal Register. We have taken steps to ensure the accuracy of this version, but
it is not the official version.

Decision-makers who are to submit an NOI and are defined as large entities (as defined in
Appendix A of the draft 2021 PGP)) must keep the following records as identified in Part 7.4 of
the draft 2021 PGP.

a.	Copy of the NOI submitted to EPA, any correspondence exchanged between the

Decision-maker and EPA specific to coverage under this permit, and a copy of the EPA

acknowledgment letter with the assigned permit tracking number;

b.	A copy of the PDMP, including any modifications made to the PDMP during the term

of this permit;

c.	Copy of annual reports submitted to EPA;

d.	Documentation of equipment calibration (only if Decision-maker is also the

Applicator);

e.	Information on each treatment area to which pesticides are discharged, including:

1.	Description of each treatment area, including location and size (acres or linear feet)
of treatment area and identification of any waters of the United States, either by
name or by location, to which pesticide(s) are discharged;

2.	Pesticide use pattern(s) (i.e., mosquito and other flying insects, weed and algae,
animal pest, or forest canopy);

3.	Target pest(s) and explanation of need for pest control;

4.	Action Thresholds;

5.	Method and/or data used to determine that action threshold(s) has been met;

6.	Description of pest management measure(s) implemented prior to the first pesticide
application;

7.	Company name and contact information for pesticide applicator;

8.	Name of each pesticide product used including the EPA registration number;

9.	Quantity of each pesticide product applied to each treatment area;

10.	Pesticide application date(s); and

11.	Whether or not visual monitoring was conducted during pesticide application and/or
post-application and if not, why not and whether any unusual or unexpected effects
identified to non-target organisms.

7.5	Retention of Records

All required records must be prepared as soon as possible but no later than 14 days
following completion of the associated activity. Operators must retain copies of these documents
for a period of at least 3 years from the date their coverage under this permit expires or is
terminated.

EPA recommends that all Decision-makers keep records of acres or linear miles treated
each calendar year for all applicable use patterns covered under this general permit. This record
will help Decision-makers estimate when they will exceed the annual treatment area threshold
(requiring submission of an NOI), or to complete an annual report if required.

7.6	Annual Reports

In addition to recordkeeping, EPA is requiring Decision-makers who are required to submit
an NOI and are large entities as identified in Part 5 of the draft 2021 PGP to submit annual

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Note: This document is aprepublication version, signed by all 10 U.S. EPA Regions on December 14, 2020. EPA is
submitting it for publication in the Federal Register. We have taken steps to ensure the accuracy of this version, but
it is not the official version.

reports that contain basic information on their pollutant discharges to waters of the United States.
An annual report form, along with instructions on how to complete it is available in Appendix G
of the draft 2021 PGP.

The annual report must include information for the calendar year, with the first annual
report required to include activities for the portion of the calendar year after the effective date of
the NOI. If the effective date of the NOI is after December 1, the Operator is not required to
submit an annual report for that first partial year but must submit annual reports thereafter, with
the first annual report submitted also including information from the first partial year. When an
Operator terminates permit coverage, as specified in Part 1.2.5 of the draft 2021 PGP, the
Operator must submit an annual report for the portion of the year up through the date of the
termination. The annual report is due no later than 45 days after the termination date, or February
15 of the following year, whichever is earlier.

This information in the annual report will be used by EPA to assess permit compliance and
to determine whether additional controls on pollutant discharges are necessary to protect water
quality. For example, these data will help the Agency identify where pollutant discharges are
occurring, and the types of pesticides being discharged. The annual report provides specific
information concerning the scope and nature of discharges of pollutants permitted under the draft
2021 PGP. Annual reports submitted under EPA 2011 PGP and 2016 PGP are available online at
https://www.epa.gov/npdes/pesticide-permitting. A summary of data submitted in the annual
reports is in the administrative record for this draft 2021 PGP. See 2017-2019 PGP Annual
Report Data document in the docket at EPA-HQ-OW-2020-0005.

The annual report is a summary of the pest control activities for each applicable use pattern
and must contain:

a.	Decision-maker's name and contact information;

b.	NPDES permit tracking number(s);

c.	Contact person name, title, e-mail address (if any), and phone number; and

d.	For each treatment area, report the following information:

1.	Description of treatment area, including location and size (acres or linear feet) of
treatment area and identification of any waters of the United States, either by name
or by location, to which pesticide(s) are discharged;

2.	Pesticide use pattern(s) {i.e., mosquito and other flying insects, weed and algae,
animal pest, or forest canopy) and target pest(s);

3.	Company name(s) and contact information for pesticide applicator(s), if different
from the Decision-maker;

4.	Total amount of each pesticide product applied for the reporting year by the EPA
registration number(s) and by application method {e.g., aerially by fixed-wing or
rotary aircraft, ground based spray, etc.);

5.	Whether this pest control activity was addressed in a PDMP prior to pesticide
application;

6.	If applicable, any adverse incidents as a result of these treatment(s), for incidents, as
described in Part 6.4.1; and

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7. If applicable, description of any corrective action(s), including spill responses,
resulting from pesticide application activities and the rationale for such action(s).

7.7 Annual Reporting for Any Decision-maker with Discharges of Pollutants to Waters of

the United States Containing NMFS Listed Resources of Concern, as Defined in

Appendix A of the Permit, and Who is a Small Entity

Any Decision-maker who is required to submit an NOI for discharges of pollutants to
waters of the United States containing NMFS Listed Resources of Concern, as defined in
Appendix A of the draft 2021 PGP, and is a small entity, as defined in Appendix A of the draft
2021 PGP, must submit an annual report to EPA. Large entities with discharges of pollutants to
waters of the United States containing NMFS Listed Resources of Concern are required to
submit annual reports consistent with Part 7.6 of the draft 2021 PGP. Decision-makers must
submit the annual report electronically through EPA's NPDES eReporting Tool (NeT), available
at https://www.epa.gov/npdes/pesticide-permitting. unless NeT is otherwise unavailable or the
Decision-maker meets the waiver requirements for submitting a paper annual report. Decision-
makers waived from the requirement to use NeT for annual report submission must certify on the
paper annual report submitted to EPA the rationale for eligibility to use the waiver. The annual
report must be submitted to EPA Headquarters (either through NeT or if NeT is otherwise
unavailable or the Decision-maker meets the NeT waiver requirement, to the EPA Headquarters
address identified in Part 8.1 of the draft 2021 PGP) no later than February 15 of the following
year for all pesticide activities covered under this permit occurring during the previous calendar
year. Annual reporting requirements begin with those activities occurring during calendar year
2022.

When Decision-makers terminate permit coverage, as specified in Part 1.2.5 of the draft
2021 PGP, an annual report must be submitted for the portion of the year up through the date of
termination. The annual report is due no later than February 15 of the next year.

For small entities, the annual report is a summary of the pest control activities for each
applicable use pattern that results in a discharge of pollutants to waters of the United States
containing a NMFS Listed Resource of Concern, as defined in Appendix A of the draft 2021
PGP. For small entities, discharges of pollutants to waters that do not contain NMFS Listed
Resources of Concern do not need to be included in the annual report. The annual report must
contain:

a. Decision-maker's name and contact information;

b. NPDES permit tracking number(s);

c. Contact person name, title, e-mail address (if any), and phone number; and

d. For each treatment area, report the following information:

1. Description of treatment area, including location and size (acres or linear feet) of
treatment area and identification of any waters of the United States, either by name
or by location, to which pesticide(s) are discharged;

2. Pesticide use pattern(s) {i.e., mosquito and other flying insects, weed and algae,
animal pest, or forest canopy) and target pest(s);

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Note: This document is aprepublication version, signed by all 10 U.S. EPA Regions on December 14, 2020. EPA is
submitting it for publication in the Federal Register. We have taken steps to ensure the accuracy of this version, but
it is not the official version.

3.	Company name(s) and contact information for pesticide applicator(s), if different
from the Decision-maker;

4.	Total amount of each pesticide product applied for the reporting year by the EPA
registration number(s) and by application method (e.g., aerially by fixed-wing or
rotary aircraft, ground based spray, etc.);

5.	The approximate date of any discharge of pollutants;

6.	If applicable, any adverse incidents as a result of these treatment(s), for incidents, as
described in Part 6.4.1; and

7.	If applicable, description of any corrective action(s), including spill responses,
resulting from pesticide application activities and the rationale for such action(s).

7.8 Electronic Reporting Requirement

Any Decision-makers required to submit Notices of Intent (NOIs), Notices of Termination
(NOTs), and/or Annual Reports, must submit them electronically unless a waiver is granted. Part
7.8 of the draft 2021 PGP outlines the conditions for obtaining a waiver. The draft 2021 PGP
requires that all NOIs, NOTs, and annual reports be submitted electronically, unless EPA's
NPDES eReporting Tool (NeT) is otherwise unavailable or the Decision-maker has obtained a
waiver from the requirement to use the NeT. Electronic reporting improves efficiency for both
Decision-makers and EPA and allows Decision-makers to obtain authorization to discharge in a
timely manner (as is important for many pesticide applications).

In those rare cases where Decision-makers are unable to report electronically, the draft
2021 PGP contains language that allows for hard copy submittal of information when the
following exemptions apply: (1) If the Decision-maker is physically located in a geographic area
(i.e., zip code or census tract) that is identified as under-served for broadband Internet access in
the most recent report from the Federal Communications Commission; or (2) If the Decision-
maker has limitations regarding available computer access or computer capability. A Decision-
maker who wishes to use paper submittals must submit a request to the EPA contact in the
appropriate EPA Regional Office listed in Part 8 of the draft 2021 PGP to obtain a waiver from
submitting reports electronically.

8.	EPA Contact and Mailing Addresses

Part 8 of the draft 2021 PGP identifies contact information and mailing addresses for any
applicable reporting requirements of the draft 2021 PGP. Note that depending on the
requirement, some reports/notifications are to go to the EPA Regional office while others are to
be sent to an EPA Headquarters location. Generally, Regions are notified for information that
may require rapid review and response by the Region to address potential adverse effects or
other concerns requiring more immediate attention.

9.	Permit Conditions Applicable to Specific States, Indian Country, or Territories

Part 9.0 of the draft 2021 PGP, when finalized, will include specific permit conditions
provided by states, territories, and tribes as part of their Clean Water Act (CWA) Section 401
certifications and their Coastal Zone Management Act (CZMA) concurrences.

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EPA cannot issue an NPDES permit until the state, territory or tribe in which the discharge
originates certifies that the discharge will comply with applicable provisions of the CWA, or
waives certification. Part 9 of the final 2021 PGP will identify provisions provided to EPA by
States, Territories and Tribes in their CWA § 401 certifications that the States, Territories and
Tribes deem necessary to assure compliance with applicable provisions of the CWA and any
other appropriate requirements of State, Territory and Tribal law. See 33 U.S.C. 1341(d); 40
CFR § 124.53(e)(1). Pursuant to CWA § 401(d), EPA will attach those State, Territory and
Tribal provisions to the final 2021 PGP; those that constitute effluent or other limitations or
monitoring requirements are enforceable conditions of the federal permit. American Rivers, Inc.
v. FERC, 129 F.3d 99, 107 (2nd Cir. 1997). These conditions are subject to review in State,
Territory and Tribal administrative and judicial tribunals with appropriate jurisdiction. 40 CFR §
124.55(e); American Rivers, Inc. v. FERC, 129 F.3d 99, 102 (2nd Cir. 1997); Roosevelt
Campobello Int'l Park Comm'nv. EPA, 684 F.2d 1041, 1056 (1st Cir. 1982).

The Coastal Zone Management Act (CZMA) and its implementing regulations (15 CFR
Part 930) require that any Federal licensed activity directly affecting the coastal zone of a state
with an approved Coastal Zone Management Program (CZMP) be consistent with the
enforceable policies of that approved program to the maximum extent practicable. Agency
general permits that do not involve case-by-case or individualized determinations by the Agency
are federal activities for the purposes of CZMA section 307(c)(1). For the final 2021 PGP, EPA
will make a consistency determination regarding the enforceable policies in each approved state
CZM program for the coastal zones including state waters where the final 2021 PGP authorizes
discharges of pollutants. [15 CFR 930.31(d)],

10. Permit Appendices

A. Definitions and Acronyms

Appendix A of the draft 2021 PGP provides permit-specific definitions of statutory,
regulatory, and other terms important for understanding its requirements. Any terms that are not
listed in this definitions part have the meaning given to the terms by 40 CFR Part 122.2 (the
definitions section of the NPDES regulations). To develop these definitions, EPA has, where
possible, relied on existing definitions in other laws and regulations applicable to this universe of
permittees in order to provide consistency with those laws and provide permittees with a familiar
framework.

B. Standard Permit Conditions

Federal regulations require that all NPDES permits contain the standard permit conditions
specified in 40 CFR 122.41. Appendix B of the draft 2021 PGP includes all of the standard
permit conditions published in federal regulations at 40 CFR §122.41.

C. Areas Covered

As noted above, the draft 2021 PGP when final will be available in those areas where EPA
remains the NPDES permitting authority for discharges from the application of pesticides to or
over, including near, waters of the United States. NPDES-authorized states issue permits

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elsewhere in the United States for these types of discharges of pollutants. Appendix C of the
draft 2021 PGP includes a list of those areas where this EPA permit is available which includes
portions of all ten EPA Regions where EPA remains the NPDES permitting authority.

D. Notice of Intent Form

Part 1.2.2 of the draft 2021 PGP identifies certain Decision-makers required to prepare and
submit a complete and accurate Notice of Intent (NOI) form to be authorized to discharge
pollutants under the draft 2021 PGP. Decision-makers must submit NOIs in accordance with the
deadlines provided in Part 1.2.3 of the PGP. The NOI form provides EPA with the information
necessary to determine a Decision-maker's eligibility to discharge pollutants under this permit
and enables EPA to better match up Operators with other reporting requirements and to prioritize
oversight activities. Appendix D of the draft 2021 PGP contains information that is required to
be provided on the NOI form. Except in special circumstances, EPA requires that Decision-
makers submit that information electronically, using EPA's NeT available at
https://www.epa.gov/npdes/pesticide-permitting. because it is easier (including availability of
online instructions and help menus to guide you through the process), faster (NOIs can be
processed 2 weeks or more faster than paper forms), and more accurate (NeT will ensure form is
completed and will auto check certain key elements to improve accuracy of information
submitted). See Part 7.8 of the draft 2021 PGP for waiver information.

E. Notice of Termination Form

Part 1.2.5 of the draft 2021 PGP requires certain Decision-makers (i.e., those required to
submit an NOI to be authorized under this permit) to submit a Notice of Termination (NOT)
form within 30 days of the occurrence of one of several different triggering events: (1) when a
new Decision-maker has taken over responsibility for the pest control activity, (2) the Decision-
maker has ceased aquatic pesticide application covered under the general permit, (3) there is not
and no longer will be pollutant discharge, or (4) the Decision-maker has obtained coverage under
an individual permit or an alternative general permit. Appendix E of the PGP contains a copy of
the information required to be submitted on the NOT form. Like the NOI, EPA requires that
Decision-makers complete and submit the NOT form electronically using EPA's NeT available
at https://www.epa.gov/npdes/pesticide-permitting. except in specified circumstances. See Part
7.8 of the draft 2021 PGP for waiver information.

F. Pesticide Discharge Evaluation Worksheet

Part 7.3 of the draft 2021 PGP requires Decision-makers who are required to submit an
NOI and are small entities, as defined in Appendix A of the draft 2021 PGP, to complete and
retain a worksheet for at least 3 years from when an Operator's coverage under the draft 2021
PGP expires or is terminated. Decision-makers are required to make this worksheet available to
EPA, including an authorized representative of EPA, upon requires. Appendix F of the draft
2021 PGP contains a copy of the worksheet required to be retained by Decision-makers.

G. Annual Report Template

Part 7.6 of the draft 2021 PGP requires Decision-makers who: (1) are required to submit an
NOI and are large entities, as identified in Part 5 of the draft 2021 PGP; and/or (2) discharge of

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pollutants to waters of the United States containing NMFS Listed Resources of Concern, to
submit Annual Reports. The Annual Report must be submitted no later than February 15 of the
following year for all pesticide activities covered under the draft 2021 PGP occurring during the
previous calendar year. When Decision-makers terminate permit coverage, as specified in Part
1.2.5 of the draft 2021 PGP, an Annual Report must be submitted for the portion of the year up
through the date of termination. Appendix G of the draft 2021 PGP contains a copy of the
information required to be submitted with an Annual Report. Like the NOI and NOT, EPA
requires that Decision-makers complete and submit the Annual Report form electronically using
EPA's NeT that is available for use at https://www.epa.gov/npdes/pesticide-permitting unless
eNOI is otherwise unavailable or the Decision-maker has obtained a waiver from the
requirement to use NeT for submitting the Annual Report. See Part 7.8 of the draft 2021 PGP for
waiver information.

H. Adverse Incident Report Template

Part 6.4 of the draft 2021 PGP requires Operators to: (1) provide oral notice to EPA within
24 hours, and (2) submit a written report within 30 days of becoming aware of an adverse
incident which may have resulted from a discharge from the Operator's pesticide application.
Adverse Incident, as defined in the draft 2021 PGP Appendix A, is an unusual or unexpected
incident that an Operator has observed upon inspection or of which the Operator otherwise
become aware, in which: (1) There is evidence that a person or non-target organism has likely
been exposed to a pesticide residue, and (2) The person or non-target organism suffered a toxic
or adverse effect. Appendix H of the draft 2021 PGP contains a copy of the information required
to be submitted to the appropriate EPA Regional office and to the State Lead Agency within 30
days of discovering the adverse incident.

I. Endangered Species Procedures

The draft 2021 PGP specifies procedures to protect federally-listed endangered and
threatened species and its designated critical habitat. EPA is proposing to retain the procedures
included in the EPA's 2016 final PGP. EPA is currently conducting consultation with the
Services (National Marine Fisheries Service (NMFS) and U.S. Fish and Wildlife Service) for the
reissuance of the draft 2021 PGP. Based on the results of consultation with the Services, EPA
may include additional or altered conditions to the draft 2021 PGP.

As discussed in section 1.1.2.4 of the draft 2021 PGP, coverage under this permit is
available only for discharges of pollutants and discharge-related activities that are not likely to
adversely affect species that are federally-listed as endangered or threatened under the ESA or
federally-designated critical habitat under the ESA, except as provided in Criterion B, C and, for
60 day, D. For discharges of pollutants to a subset of these resources, identified in this permit as
NMFS Listed Resources of Concern, which are defined in Appendix A of the draft 2021 PGP,
the operator must document that discharges of pollutants meet these conditions by certifying
eligibility under one of Criteria A-F. (Note that operators not otherwise required to submit an
NOI do not need to do so merely to certify under Criterion A, which indicates that discharges of
pollutants will not occur to waters of the U.S. where NMFS Listed Resources of Concern are
present.) Appendix I contains a four-step process that must be followed for determining whether

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submitting it for publication in the Federal Register. We have taken steps to ensure the accuracy of this version, but
it is not the official version.

an Operator is eligible for permit coverage, prior to submittal of the NOI. In order to become
eligible for this permit, each Operator must determine its compliance with one of six criteria (A -
F). If Operators cannot determine if they meet one of the eligibility criteria related to NMFS
Listed Resources of Concern, the operator cannot submit an NOI to gain coverage under the draft
2021 PGP. In these instances, the Operator may consider applying to EPA for an individual
NPDES permit.

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Note: This document is aprepublication version, signed by all 10 U.S. EPA Regions on December 14, 2020. EPA is
submitting it for publication in the Federal Register. We have taken steps to ensure the accuracy of this version, but
it is not the official version.

IV. Fact Sheet Appendices

APPENDIX A. List of Pesticides and Degradates Which Exceeded Aquatic-life
Benchmarks in the USGS 2014 Study and the CA Central Valley Regional 303(d)
Impairment List of Pesticides.

Table Al. Sites that exceed one or more aquatic-life benchmarks in the last decade (2002-2011) USGS 2014

Pcsticidc/Dcgradatc

Sites that exceed one or more aquatic-life benchmarks

Agricultural sites

U rban Sites

Mixed sites

Total cxcecdances

Acetochlor

2





2

Alfa-endosulfan





1

1

Atrazine

1





1

AZM

5

1

2

8

Carbofuran

2



1

3

Carbaryl

1

5



6

Chlorpyrifos

4





4

Cis-permethrin

2

2

5

9

Diazinon

1

4

2

7

Disulfoton

2

1

1

4

Disulfoton-sulfone



1



1

Dichlorvos

1

19

3

23

Dicrotophos

1





1

Ethoprophos

1





1

Fipronil

10

52

23

85

Fipronil sulfone



2



2

Lambda-cyhalothrin

1



1

2

Linuron



3



3

Malathion

7

12

8

27

Metolachlor

32

1

34

67

Parathion-methyl

1





1

Table Ala. Percentage of sites that exceed one or more aquatic-life benchmarks in the last decade (2002-2011)

Pcsticidc/Dcgradatc

Percentage of sites that exceed one or more aquatic-life
benchmarks

Agricultural sites

U rban Sites

Mixed sites

Acetochlor

9.1

0.0

0.0

Alfa-endosulfan

0.0

0.0

3.7

Atrazine

4.5

0.0

0.0

AZM

13.6

3.7

7.4

Carbofuran

4.5

0.0

3.7

Carbaryl

4.5

7.4

0.0

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Chlorpyrifos

9.1

0.0

Cis-permethrin

4.5

7.4

18.5

Diazinon

4.5

11.1

7.4

Disulfoton

9.1

3.7

Disulfoton-sulfone

0.0

3.7

0.0

Dichlorvos

4.5

51.9

11.1

Dicrotophos

4.5

0.0

Ethoprophos

4.5

0.0

Fipronil

36.4

77.8

48.1

Fipronil sulfone

0.0

7.4

0.0

Lambda-cyhalotMn

4.5

0.0

3.7

Linuron

0.0

11.1

0.0

Malathion

27.3

33.3

18.5

Metolachlor

63.6

3.7

29.6

Parathion-methyl

4.5

0.0

Table A2. Pesticides/Degradates that are listed as 303(d) impairments from the CA Central Valley (USEPA

Approved 2008-2010 list)

Note: This table includes pesticides that have been cancelled.

Pesticide/Degradate

#of

impairments

WQS being exceeded

Aldicarb

Narrative toxicity and pesticide objectives - one-tenth the 48-
hr LC50 Chironomus tentans.

Azinphos-methyl

Narrative toxicity and pesticide objectives - USEPA ambient
water quality criteria (USEPA, 1976).

Bifenthrin

Narrative toxicity and pesticide objectives - one tenth the 96-
hour LC50 for Haylella azteca.

Carbofuran

Narrative toxicity and pesticide objectives - USEPA
recommended water quality criterion for the protection of
freshwater aquatic life.

Chlordane

Fish tissue samples exceed narrative toxicity objective.
Composites exceeded the 5.6 ug/kg OEHHA screening value
for total chlordane in fish tissue.

Chlorpyrifos

Numeric site-specific water quality objective for chlorpyrifos
or narrative toxicity and pesticides objective - exceedance of
1-hour and/or 4-day average maximum concentration
criterion above the allowable frequency.

DDD

Samples exceeded the California Toxic Rule/USEPA
(CTR/USEPA) criteria limit of 0.00083 |ig/L for DDD based
on a human health carcinogenic risk level of 10-6 for
consumption of water and aquatic organisms.

DDE

Samples exceed the 0.00059 |ig/L California Toxic
Rule/USEPA (CTR/USEPA) criteria limit based on a human
health 10-6 carcinogenic risk level for consumption of water
and aquatic organisms for DDE.

DDT

Placeholder to support decision made prior to 2006.

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Pesticide/Degradate

#of

impairments

WQS being exceeded

Diazinon

Numeric site-specific water quality objective for diazinon or
narrative toxicity and pesticides objectives - exceedances of
1-hour and/or 4-day average maximum concentration
criterion above the allowable frequency.

Dichlorvos

Narrative toxicity and pesticides objectives - one-tenth the
96-hour LC50 for Daphnia magna.

Dieldrin

Samples exceed the California Toxic Rule/USEPA
(CTR/USEPA) criteria for Dieldrin of 0.00014 |ig/L based on
a human health 10-6 carcinogenic risk level for water and fish
consumption.

Dimethoate

Narrative toxicity and pesticides objectives - one-tenth LC50
for the most sensitive species in freshwater (Cyclops
strenuus, a copepod crustacean).

Disulfoton

Narrative toxicity and pesticides objectives - USEPA
National Ambient Water Quality Disulfoton Criterion for
freshwater aquatic life protection, maximum concentration of
0.05 ug/L.

Diuron

Narrative toxicity and pesticides objectives - the 96-hour
EC50 for Chlorella pyrenoidosa (1.3 ug/L).

Group A Pesticides

Placeholder to support decision made prior to 2006.

Hexachlorobenzene/ HCB

Samples exceed USEPA IRIS Reference Dose (RfD) for
maximum Hexachlorobenzene content in surface water with a
limit of < 0.00075 ug/L.

Lindane/ gamma
Hexachlorohexane (gamma
HCL)

Samples exceeded the CTR criteria of 0.019 mg/g for human
consumption of water and organisms.

Malathion

Narrative toxicity and pesticides objectives - The USEPA
recommended 4-day average criterion continuous
concentration (CCC) (0.1 ug/L) (USEPA, 1976). The
California Department of Fish and Game Hazard Assessment
Criterion 1-hr average concentration (CMC) (0.43 ug/L)
(CDFG, 1998)..

Organophosphorus
Pesticides

Narrative toxicity and pesticides objectives - Toxicity and
chemistry results indicating organophosphorus pesticide
toxicity..

Oxyfluorfen

Narrative toxicity and pesticides objectives - the 96-hour
EC50 for Selenastrum capricornutum, a green algae.

cis-Permethrin

Narrative toxicity and pesticides objectives - one-tenth the
LC50 value for the most sensitive freshwater species,
Tanytarsus sp.

Prometryn

Narrative toxicity objective; 96-hour EC50 value for
Navicula pelliculosa, a freshwater diatom.

Pyrethroids

Narrative toxicity objective; sediment-bound toxicity;
chemical analysis; and TIE manipulations indicate pyrethroid
pesticides are the likely cause.

Simazine

Drinking water primary Maximum Contaminant Limit
(MCL) (4 ug/L).

Toxaphene

Samples exceeded the OEHHA Screening Value (30 ng/g).

Triflnralin

Narrative toxicity and pesticides objectives; interpreted using
LOEC for Pimephales promelas of 0.7 ug/L.

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Note: This document is aprepublication version, signed by all 10 U.S. EPA Regions on December 14, 2020. EPA is
submitting it for publication in the Federal Register. We have taken steps to ensure the accuracy of this version, but
it is not the official version.

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APPENDIX B. Chemicals and Exceedances in USGS 2014 Study and Subsequent
Mitigation Measures that Reduce Pesticides Residues in Waters.

Chemical

Recent Actions

Acetochlor

Acetochlor is currently undergoing Registration Review31.

Atrazine

Intensive monitoring program (2003 IRED). Atrazine is currently
undergoing Registration Review.

Azinphos-methyl

In 2006, EPA issued its final decision on Azinphos-methyl that phased
out the remaining uses by September 30, 2012.

Carbaryl

Lawn broadcast uses of liquid formulations cancelled; certain other
uses and application methods cancelled; reduced application rates for
some uses; prohibit most aerial applications (2003 IRED). Carbaryl is
currently undergoing Registration Review.

Carbofuran

Domestic sales phased out in 2013 (2006 IRED). Technical
registrations remain for export of the active ingredient.

Chlorpyrifos

Residential uses cancelled (except for roach baits in child-resistant
packaging and ant mound treatments); agricultural use restrictions
including reduced application rates and fewer applications per season,
increase in retreatment intervals and addition of buffer zones around
water bodies; some aerial application uses cancelled (2001 IRED).
Chlorpyrifos is currently undergoing Registration Review.

Cis-permethrin

Standard pyrethroid specific spray drift language, including a 25 foot
aquatic buffer zone for ground applications, 100-foot for aerial
application, and 450 foot for ULV applications; amended agricultural
labels to include new use pattern (rate reductions, seasonal maximum
reductions, and minimum retreatment interval) identified for the
selected crop uses (2006 RED). Cis-permethrin is currently undergoing
Registration Review.

Diazinon

Residential uses and granular uses cancelled; aerial application
cancelled; seed treatment uses cancelled (2002 IRED). Diazinon is
currently undergoing Registration Review.

Dichlorvos (DDVP)

Dichlorvos is currently undergoing Registration Review.

Dicrotophos

Dicrotophos is currently undergoing Registration Review.

Disulfoton

Cancellations for EPA Reg. Nos. 264-723, 264-734, 5481-8989, and
432-1286 were effective December 31, 2009. Cancellations EPA Reg.
Nos. 264-725 and 72155-49 were effective December 31, 2010. All
disulfoton registrations are now cancelled (2002 IRED).

Endosulfan

In July 2010, EPA signed a Memorandum of Agreement with the
registrants of endosulfan that resulted in voluntary cancellation and

31 For a current Registration Review schedule, please go to: https://www.epa.gov/pesticide-
reevaluation/registration-review-schedules

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Note: This document is aprepublication version, signed by all 10 U.S. EPA Regions on December 14, 2020. EPA is
submitting it for publication in the Federal Register. We have taken steps to ensure the accuracy of this version, but
it is not the official version.



phase-out of all existing endosulfan uses in the U.S. the last endosulfan
uses ended on July 31, 2016, and there are currently no existing
registrations.

Ethoprophos

Ethoprophos is currently undergoing Registration Review.

Fipronil

Fipronil is currently undergoing Registration Review.

Lambda-Cyhalothrin

Lambda-Cyhalothrin is currently undergoing Registration Review.

Linuron

Linuron is currently undergoing Registration Review.

Malathion

Some uses cancelled; reduced application rates and frequency of
application for many crops; 25 and 50 foot buffer zones for non-ULV
and ULV aerial applications near water bodies; droplet size, wind
speed, and application altitude specifications for mosquito adulticide
use; spray drift minimization label statements for agricultural and
public health products; environmental hazard precautionary label
statements required for agricultural, public health, and residential
products (2006 RED; 2009 RED Revision). Malathion is currently
undergoing Registration Review.

Methyl -parathi on

On July 16, 2010 the cancellation order to voluntarily cancel all
product registrations containing methyl parathion was published. This
cancellation order terminated the last methyl parathion products
registered for use in the U.S., effective December 31, 2012. End-use
products could not be sold after August 31, 2013, and end-use products
cannot legally be used after December 31, 2013. There are currently no
existing end-use registrations.

S-metolachlor

S-metolachlor is currently undergoing Registration Review.

APPENDIX C. Summary of Pesticide-Specific Exceedance Data and Risk Mitigation
Actions.

•	Of the 75 pesticides and 8 degradates analyzed, 19 pesticides in use at the time of the
USGS 2014 study were measured at concentrations that exceeded EPA benchmarks: 4
herbicides (acetochlor, atrazine, linuron, and metalochlor SS) and 15 insecticides
(azinphos-methyl, carbaryl, carbofuran, cis-permethrin, chlorpyrifos, diazinon,
dichlorvos, dichlorovos, disulfoton, endosulfan, ethoprophos, fipronil, lambda-
cyhalothrin malathion, and methyl parathion).

•	Six pesticides accounted for the majority of the exceedances: fipronil, S-metolachlor,
malathion, dichlorvos, cis-permethrin, and azinphos-methyl. These pesticides are
discussed in more detail below:

Fipronil

Fipronil entered Registration Review in June of 2011. The preliminary risk assessments for
fipronil are expected to be completed in 2020. Any potential mitigation would be included in a
proposed registration review decision.

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S-metolachlor

Metolachlor and S-metolachlor entered Registration Review in December of 2014. The
preliminary risk assessments for metolachlor and S-metolachlor are were publish in 2019. Any
potential mitigation would be included in a proposed registration review decision.

Malathion

The revision of the malathion RED was completed in 2009. Mitigation required by the RED
reduced maximum application rates and the number of applications allowed annually.

Malathion entered Registration Review in June of 2011. The preliminary human health risk
assessment for malathion published in August of 2016. The draft biological evaluation, with
coordination from both The National Marine Fisheries Service and US Fish and Wildlife
Services, including an endangered species and environmental fate and effects risk assessment
published in April 2016. The draft biological evaluation identified potential risks to listed birds,
mammals, amphibians, reptiles, terrestrial invertebrates, fish, aquatic invertebrates, and plants.
EPA also made "likely to adversely affect" determinations for 97% of all listed species assessed
and "likely to adversely affect determinations" for 99% of all critical habitats as a result of
current labeled malathion usage. Any potential mitigation would be included in a proposed
registration review decision.

Dichlorvos (DDVP)

Dichlorvos entered Registration Review in June of 2009. The preliminary risk assessments for
dichlorvos are expected to be published in 2020. Any potential mitigation would be included in a
proposed registration review decision.

Cis-permethrin

The permethrin RED was completed in 2006. Mitigation included standard pyrethroid specific
spray drift language, including a 25-foot aquatic buffer one for ground applications, 100-foot for
aerial application, and 450 foot for ULV applications. Agricultural labels were amended to
include new use pattern (rate reductions, seasonal maximum reductions, and minimum
retreatment interval) identified for the selected crop uses. Include stewardship language in the
directions for use section of all products registered for outdoor use in residential areas.
Cis-permethrin entered Registration Review in June of 2011. The preliminary risk assessments
for cis-permethrin were published in 2016. Any potential mitigation would be included in a
proposed registration review decision.

Azinphos-methyl

As part of EPA's 2006 final decision on azinphos-methyl all remaining uses were phased out by
September 30, 2012.

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U.S. Environmental Protection Agency	Draft 2021 NPDES Pesticide General Permit Fact Sheet

Note: This document is aprepublication version, signed by all 10 U.S. EPA Regions on December 14, 2020. EPA is
submitting it for publication in the Federal Register. We have taken steps to ensure the accuracy of this version, but
it is not the official version.

APPENDIX D. Cost Impacts and Number of Entities Covered

EPA projects that this permit will result in no incremental cost impacts on regulated entities
since the requirements in the permit are substantively the same as those found in both the 2016
PGP as well as the 2011 PGP. For a description of EPA's estimate of the covered universe for
these two earlier versions of the PGP, please refer to "Cost Impact Analysis for the EPA 's 2016
Pesticide General Permit (PGP) " in the docket at EPA-HQ-OW-2015-0499 and "Economic
Analysis of the Pesticide General Permit (PGP) for Point Source Discharges from the
Application of Pesticides" for the 2011 PGP in the docket at EPA-HQ-OW-2010-0257-0151.

Although EPA does not anticipate any incremental cost impacts to regulated entities as a result
of reissuance of the permit, the Agency is updating its projection of entities covered by the
permit to reflect changes in NPDES permitting authorities. In particular, since issuance of the
2016 PGP, the State of Idaho received authorization to administer the entire NPDES program. As
a consequence, EPA has removed Operators in Idaho from its estimate of total number of entities
covered by the PGP since Operators in Idaho will now need to seek coverage under the state's
NPDES permitting program.

EPA also notes that subsequent to issuance of the 2016 PGP, the federal government has
formally recognized several Indian tribes. EPA has not revised the number of entities needing
PGP coverage in Indian territories since the Agency's inquiries determined that no pesticide
applications are known to occur within these newly recognized tribal lands that would require
coverage under the permit.

As shown in Table 1, EPA estimates that this draft 2021 PGP will cover approximately 14,300
Operators As a point of reference, EPA estimated for the 2016 PGP that approximately 31,000
Operators would be covered under the federal permit, out of which more than half were based in
Idaho.

Table 1: Estimate of Entities Coverec

Under the draft 2021 PGP

Hki lube Not
¦Hlioi l/i if foi

¦,,s

Mosquito
md Othn
1 lvin„ Insul
I'ist < ontiol

Wud ind
\lt,u PtM
( onliol

Vnim il Ft si
C onli ol

( mop> Pist
C onti ol

lot il |

Massachusetts

9

2,153

26

214

2,402

New Hampshire

44

642

10

85

781

New Mexico

13

10,285

8

26

10,332

District of
Columbia

1

8

2

0

11

Territories

1

314

38

4

357

Tribes

17

93

25

34

169

Federal Facilities

65

65

65

50

245

Total

150

13,560

174

413

14,297

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U.S. Environmental Protection Agency

EPA continues to estimate that a total of 365,000 Operators across the U.S. will be covered
under state-issued NPDES PGPs and the federal NPDES PGPs together.

This permit specifies procedures to assist in protecting federally-listed endangered and
threatened species and federally designated critical habitats under the Endangered Species Act
(ESA). These procedures are carried forward from EPA's 2016 PGP and only apply to Decision-
makers in the limited areas where NMFS Listed Resources of Concern, as defined in Appendix
A of the draft 2021 PGP, are present. EPA estimated 714 potentially affected entities which
overlap with NMFS Listed Resources of Concern for the 2011 PGP. As in the 2011 PGP, these
are potentially affected entities who may (in addition to other costs as a result of the permit)
incur costs solely because of discharges of pollutants to waters of the United States containing
NMFS Listed Resources of Concern. Though this permit will not cover pesticide discharges in
the State of Idaho and may extend to pesticide activities in the newly recognized Indian tribes;
EPA continues to estimate that less than 2 percent of the total number of Operators would need
to meet additional permit requirements beyond those in the draft 2021 PGP's ESA related
provisions. Under the 2016 PGP, EPA received less than 50 Notices of Intent that included areas
which overlap with NMFS Listed Resources of Concern. EPA is not changing the estimated
potentially affected entities value (714), as any additional potential entities are captured in that
value based on actual data.

EPA acknowledges the difficulty of developing definitive estimates of entities and activities
potentially covered under this permit and points to two main limitations of the available data.
First, no direct source of information exists on the number of Applicators or patterns of
application for aquatic pesticides. As a result, EPA needed to derive its estimates from
secondary sources of information, and in some cases it needed to make a variety of assumptions.
Second, the CWA does not define the terms "application" or "applicator" as it relates to
discharges from pesticide applications, so available data may not all use similar definitions of
these terms.

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