Animas River Stakeholders Group January 26, 2016

 Last Hearing That Made Major Changes in Upper Animas Standards Was 2001, When WQCC Adopted ARSG’s Recommendations.  Issues Formulation Hearing – Nov  Rulemaking Hearing – June 2017 (in Durango).

 STREAM SEGMENTS Determined by topography, geology, water quality, jurisdictional boundaries, stream flow characteristics, temperature, aquatic life, etc.  USE CLASSIFICATIONS Determined by what uses are present or are expected or anticipated to be present in the future. Agriculture, Water Supply, Aquatic Life (Class 1 or 2, cold or warm), Recreation, and Wetlands  STANDARDS Designed to protect the Use Classifications Standards set to protect the most vulnerable use

 Table Value Standards (TVS) are designed to protect 95% of all aquatic species.  TVS is applied to most stream segments.  For most metals, TVS is a hardness-based equation for dissolved metals.  For iron and aluminum, TVS is determined by total recoverable.  For some metals, TVS is a specific number.

 Mineral Creek – Segments 8, 9, unnamed.  Cement Creek – Segment 7.  Animas abv Cement Cr. – Segments 2, 3a,3c, 17.  Animas blw Cement Cr. – Segments 3b, 4a,4b.

 Need to designate a segment for Porphyry Gulch, Mill Creek, Big Horn Creek, South Mineral Creek, and Bear Creek.  May want to re-segment 8 and add aquatic class 2 classification to part of 8.  Need to review stds for iron, aluminum, zinc, copper, cadmium (lead?), pH for segment 9 (M34).

 Al – not close to TVS except in June. (site specific std.)  Cd – meets or is close to TVS except April – May.  Cu – meets TVS  Fe – not close to TVS except in June. (site specific std.)  Pb – probably meets TVS  Zn – meets TVS except April – May  pH – meets TVS May–Sept.(site specific std.)

 TVS for agricultural stds only. No stds for aquatic life. Zinc TVS (2,000 ug/l) exceeded in winter.  Narrative std of concentrations for achieving stds in segments 4a and 4b.  Numeric goals for meeting standards downstream?

 Site specific stds for zinc and cadmium may be needed for 3c and 17 (Arrastra Gulch).  Potentially divide 3a at Howardsville.  Review site specific stds for lower 3a for Al, Cd, Cu, Mn, Pb, Zn, and pH.

 Al – Close to meeting TVS  Cd – Above TVS year-round, six times higher than TVS in March-April. (site specific std.)  Cu – Meets TVS except in May.  Mn – Meet TVS except Dec.- April.  Pb – Probably meets TVS.  Zn – Exceeds TVS year-round. Five times higher in March-April. (site specific std.)  pH – Below TVS in Jan.- March.

 Review stds in 4a for Al, Cd, Cu, Fe, Mn, Pb, Zn, pH.  Review stds for 4b for Al, Cd, Zn.  Review dividing line between 4a and 4b at Deer Park Creek (above Elk Park).

 Al – Well abv TVS year-round. (site spec.std)  Cd – Well above TVS year-round.  Cu – Mostly meets TVS.  Fe – Well abv TVS except June–July. (site specific std.)  Pb – Mostly meets TVS.  Mn – Meets TVS except March-April.  Zn – Well abv TVS year-round (site spec. std.)

 Al – Exceeds TVS much of the year.  Cd - Exceeds TVS in spring and summer.  Fe – Exceeds TVS in winter and spring.  Zn – Exceeds TVS except in summer.  No site specific stds for 4b.

 Site specific stds for segments 9, 3a, and 4a are monthly.  Should they be seasonal? For example:  Oct. 16 – Feb. 28 – Low flow  March 1 – April 30 – Early melting.  May 1 – July 15 – Runoff.  July 16 – Oct. 15 – Seasonal rain.