Pesticide NPDES permit steps to compliance | Step 5: Requirements for large pesticide dischargers exceeding the threshold

If you are a Large Entity required to submit a Notice of Intent, you must complete additional permit requirements. A large entity means any a) public entity that serves a population of greater than 10,000 or b) private enterprise that exceeds the Small Business Administration (SBA) size standard as identified at 13 CFR 121.201. The SBA, for most industries, uses the average number of employees over the past 12 months, or average annual receipts over the past three years to determine business sizes. To determine whether your business is considered a Large Entity for this permit, visit the Small Business Administration website.

Pesticide Discharge Management Plan (PDMP)

One PDMP may include multiple treatment areas, but separate plans must be prepared for each type of pesticide application activity — for example, separate plans are required if you are treating for mosquitoes and forest canopy insect pests.

You may write your own PDMP based on the requirements in Section 4 of the permit. The requirements have been summarized in PDF icon Required Contents of Pesticide Discharge Management Plan (wq-wwprm9-06).


  • The PDMP documents your evaluation and selection of control measures.
  • In your PDMP, you may refer to procedures in other documents that meet the requirements of this permit. Keep a copy of relevant portions of those documents with your PDMP and make them available for review if requested.


If you know before starting pesticide applications that you will exceed a threshold, you must develop a PDMP before the first pesticide application. If you did not know until after starting pesticide applications that you would exceed a threshold, you must develop a PDMP before exceeding the threshold.

If you are applying pesticides in response to a declared pest emergency situation that will cause you to exceed a threshold, you must develop a PDMP no later than 90 days after responding to the declared pest emergency. These timelines are the same as the timelines for submitting your Notice of Intent (Step 2). 

Annual Reporting

Large entities that submit a NOI must also submit an Annual Report by February 15 for all activities occurring during the previous year that are covered under this permit. If you do not apply pesticides under this permit for the year, you may check "No Discharge" on the Annual Report form available below.


In addition to the recordkeeping required for All Operators, large entities that exceed a threshold must also retain a copy of the PDMP and Annual Reports. Large entities must also record Action Thresholds and methods used to determine the Action Thresholds. You must document the records no later than 15 days following pesticide application, and they must be retained for 5 years.

Go to Step 6: Report Adverse Incidents