Site-specific quality numeric permit limits: discharges to surface water and groundwater

How the Environment Agency sets and assesses discharge quality numeric limits in environmental permits.



This guide is for operators of standalone water discharge activity and point source groundwater activity permits. Standalone means the activity is not part of another regulated facility such as a waste operation, installation, radioactive substances activity, flood risk activity or mining waste operation.

The guide explains:

  • the 4 types of compliance limit
  • how we set each of these types of limits
  • how we assess compliance against the limits
Published 8 May 2018
Last updated 17 January 2019 + show all updates
  1. Updated the mean compliance limit section. We assess compliance with mean limits using pre-scheduled samples taken in any 12 consecutive months.
  2. First published.