CMA Water Quality Committee summary

May 19, 2020

The Committee discussed water quality legislative and regulatory issues.

Dianna Orf described the ongoing legislative dialogue regarding per- and polyfluoroalkyl substances (PFAS) which continues to evolve. The Committee discussed whether fire-fighting equipment used at mining operations would be subject to potential regulation. The answer may be determined by age of the product. CMA elected not to file comments on the Division’s PFAS.

Jimmy Boswell updated the Committee about regulatory activities at the Water Quality Control Division and Commission. The Division held a stakeholder briefing on the 10 year “roadmap”

Selenium was covered extensively in the briefing mentioned above, with a presentation updating stakeholders about the Division’s joint study with CSU, CPW on selenium, with interest covering brown trout. The Committee will analyze the impact to mining about dewatering.

The Committee discussed the scope of potential rulemaking changes to Regulation 31, THE BASIC STANDARDS AND METHODOLOGIES FOR SURFACE WATER. Issues likely to be covered in a future rulemaking could include temperature, shoulder seasons, transition zones and winter warm. Committee members discussed previous rulemaking proceedings in which the Division addressed these issues in the past.

The Committee followed up on a discussion from previous months about contacting other technical representatives of non-mining dischargers who possibly share concerns about permitting issues with the Water Quality Control Division.

Discussion occurred about the new EPA Waters of the United States (WOTUS) and its application to Colorado. While Jimmy Boswell indicated he would outline how the rule would apply in Colorado, subsequent developments have seen the CDPHE seek introduction of legislation returning Colorado to the “Obama” rule and the development of a dredge and fill permit program.

Poppy Staub reported that the Ouray Silver mine was inaccurately described in an Amicus Curiae brief in the Maui case recently decided by the United States Supreme Court.