What are the advantages of a discharger specific variances versus modifying a designated use and water quality criteria?

Frequently Asked Questions

A discharger specific variance would retain the underlying designated use and water quality criteria. Retaining the underlying use and criteria recognizes that although a permittee may not currently be able to meet a water quality based effluent limit, the permittee may be able to meet the limit in the future as economic conditions change, technologies improve or become cheaper and easier to operate. A discharger specific variance also requires that the permittee meet an interim effluent limit that reflects the greatest pollutant reduction achievable and that the interim effluent limits and conditions of the variance be reviewed at least every five years.