Discharger Specific Variances

A discharger specific variance is a temporary change to Wyoming’s Surface Water Quality Standards granted to a permittee in circumstances where it is not economically feasible to meet an effluent limit based on the standards. Discharger specific variances may be granted by the Water Quality Division Administrator, following consideration of public input, on an ongoing basis. Each discharger specific variance can only be as long as necessary, must be reviewed at least once every five years, and include the following:

  • a comprehensive alternatives analysis demonstrating that the most cost-effective alternative capable of achieving the effluent limit would result in substantial and widespread economic and social impacts;
  • an interim effluent condition that represents the greatest pollutant reduction achievable; and
  • a pollutant minimization plan.