Water Quality Committee Update


Monthly Bulletin

January Bulletin | WQCC Meeting

Discussed annual reports from DRMS, SEO, Oil and Gas, and Hazardous Waste (SB 181).

DRMS annual report discusses groundwater protection measures in mineral and coal mining permits. Short summaries are provided for each active operation. Provides statistics on number of inspections conducted. Lists AML projects that were assessed or reclaimed.

Discussed revisions to the WQCC discharger specific variances policy. The policy was updated to add experience from 6 DSVs that have been adopted. One policy change was incorporated that requires 303(d) listing decisions to be based on instream quality and impairment cannot be authorized by a DSV (i.e. a DSV cannot allow a new impairment or make an existing impairment worse). The WQCD explains that this approach is consistent with the Federal rule.

No mining related permits or violations issued.

Water quality forum

WQF budget shortfall. CMA has not contributed to WQF for some time. Do members consider the WQF advantageous or helpful? WQF requesting funding.

Members to consider importance of participating. Potential benefit for members by participating through CMA. Not currently in budget for 2019. At a minimum should budget for 2020.  To discuss with board and further at next meeting.

Next meeting January 22, 2019 | 12:30pm-4:30pm

CPW iron toxicity studies

CPW presented iron toxicity study during water quality forum. Includes a recalculation of the iron criteria including three new studies conducted by CPW. Recalculation resulted in standard of 0.5 mg/L. Also included results of a mesocosm study that resulted in criteria of 0.25 mg/L. Mesocosm study incorporated Fe(III) in solution and treated with NaOH for pH adjustment to maintain neutral pH. Results in flocculation of iron hydroxide (potentially within gills). Likely some exposure to Fe(III) in solution prior to precipitation also. Applicability of this type of environment (AMD) to circumneutral waters where iron source is particulate or as statewide standard is disputable.

Pursuit of a coarse prefiltration method for Colorado by some member companies was stopped by WQCD. Most appropriate approach may be similar to aluminum, which accounts for DOC, pH, and hardness of water.

Interest in internal workgroup within CMA. Allison collected names of participants. Need to be prepared to address. Next triennial review for Basic Standards Regulation 31 is 2021. If CPW intends to pursue this it will should show up at the Issues Scoping Hearing this fall. Not currently on WQCD 10-year roadmap.

Upcoming: groundwater / NPDES issue

Hydrologic connectivity, groundwater to surface water, NPDES implications (Nate Hunt) on agenda for January presentations. Also, perfluoro-alkyl-substances and 303(b) integrated reporting. WQF scheduled for January 22.

Discussion of groundwater NPDES issue has been removed from the January agenda.

Permit issues forum update

Downstream standards: Explained original basis of “downstream” language and exclusion of modeling requirements. WQCD argues that applying downstream standards has been practice historically, dischargers and examples contradict this. WQCD also implied that at basin hearings, the WQCC needed to make a specific finding that downstream standards were being protected in order to incorporate into permits. Requested some guidance on discharge demonstrations.

Flow limits: WQCD does not feel that regulatory changes are appropriate and reiterated that flow limits were a result of the mass-balance equation. WQCD suggested that it could be brought before the WQCC independently, but the WQCD would not support it.

WET: Explained that there is no guidance to distinguish between ionic imbalance and TDS toxicity. GEI suggested an alternative test method on a limited use basis. EPA and WQCD explained that in some situations toxicity needs to be reduced rather than using more tolerant species. EPA more supportive of ATP approach rather than ionic imbalance. WQCD requested additional work to narrow scope on downstream standards issue and WET testing. Flow limits postponed until CDPHE litigation decision. Reiterated limited resources of WQCD to work on these topics.

Signed on to joint permittee comments on CDPS permit Part II language. Comments focused on 1) precedent of changing permit language but not conducting official notice and comment and 2) allowing upsets for technology based and water quality-based standards.

PIF meeting scheduled Thursday January 17, 2019 1:30. Discussion topics include watershed permitting and changes to issues list.

Changing personnel at the CDPHE. Larry Wolk (Chief Medical Officer), Martha Rudolph (Environmental Director) and Ellen Howard-Kutzer (CDPS Permitting Chief) are leaving. Intend to briefly present issues to new personnel as introductory meetings take place. Jim Stark indicated that meetings were taking place, there may be some room for an MOU to address the overlap between agencies but will likely need to play some catch-up as new staff fill positions.

303(d) Listing Methodology

Released last week. Written comments due January 28.

Primary changes were regarding 1) use of confidence limit approach for ambient based standards on secondary water supply segments (good), 2) adequate refuge clause for lake temperature assessment to match standards regulation but does not substantively change the assessment approach for DO, and 3) where segments are split, the subsegments will carry over the parent segments listing status (an exception is provided where data is not available in a subsegment, the WQCD will accept other forms of analysis such as landscape analysis).

There were outstanding questions / concerns on the splitting of stream segments and application of impairments to new subsegments (parent/daughter relationship).

If members identify concerns during review, to contact Stan and Jimmy about potential for comment.

Follow-up with WQCD on Mining WQ Topics

Stormwater, point of compliance

Follow-up from DRMS / WQCD meetings, John Swartout.

WQCD 10-Year Roadmap

November meeting focused on temperature treatment feasibility. Upcoming meetings to be scheduled (February).

Cadmium technical advisory committee (TAC) to meet this afternoon. Intent for cadmium is to incorporate the newly revised Federal standard. Overall the revised cadmium standard is an improvement over current standards. Colorado will need to calculate a warm-water standard, which was not addressed in the Federal standard.


Waters of the U.S.

Categorically excludes ephemeral waters and includes intermittent and perennial waters (based on intercepting water table). Categorically include waters fed by snowpack as intermittent / perennial. Includes adjacent wetlands with surface connection to or abutting jurisdictional waters. Includes ditches in a tributary or that alter a tributary that also meet the tributary definition (intermittent / perennial to jurisdictional water). Excludes groundwater, artificially irrigated areas, mining depressions, stormwater control features in uplands, wastewater recycling structures in uplands, and waste treatment systems.

Areas for additional comment: 1) snowpack, 2) ditches, 3) upland, 4) traditional navigable waters (excluding minimal recreational use, navigability versus commerce clause)

Comments likely to be submitted by CMA on issue. Member company comments welcome. Please send to Stan and Jimmy for inclusion in CMA comments.

Aluminum water quality standard

Final standard based on hardness, pH, and DOC. Acute ranges up to 4.8 mg/L and chronic ranges up to 3.2 mg/L. Uses total recoverable analysis method. Criteria recognizes this will overestimate toxicity and will inaccurately measure particulate aluminum (clay) that is not bioavailable. EPA also discusses ongoing methods research to address. Another potential issue is that EPA extended the applicability to pH ranges that were beyond the pH in the empirical data that was used to conduct the toxicity studies. NMA working on white paper to request addressing issues with total recoverable through implementation (e.g. suspended sediment threshold or post-rain even applicability). FWQC also pursuing potential changes to total recoverable issue.

The alternative methodology research (referenced in the EPA standard) has been submitted for publication. However, it is a lengthy process to get acceptance at the Federal level. It may be more successful to implement the method with a state-by-state approach, although Colorado has not been amendable to this with other issues in the past.

EPA California selenium proposal

Removes 3.1 µg/L water column criteria and replaces with extensive site-specific standards development process. Returns primacy to fish tissue concentration over water column. Adds bird tissue threshold. Site-specific plan requires minimum of 8 samples per stream reach, extensive aquatic community documentation and analysis, and allows BAF or mechanistic model analysis.

Additional flexibility would be helpful such as 1) allowing adjustment of fish tissue criteria following aquatic community analysis, 2) incorporation of fish tissue directly into permits where site-specific standards fail, 3) development of local or regional multi-stream standards.

Construction general permit

Proposed rule made three changes: 1) eliminating examples of operator, 2) modifying three requirements a) to clarify that dust control is intended to minimize potential for dust to accumulate where it will discharge in stormwater, b) clarified that discharges should control stormwater discharges, including peak flow rates and volumes, to minimize erosion and scour at discharge points, c) excluded cover requirement from construction materials that are not a pollutant source or that are meant to be exposed to stormwater, and 3) clarified individual responsibilities in multiple operator situations.

Because the multi-sector general permit (MSGP) can now be applied during construction or operation at a mine site, this is likely not a concern. Overall the changes appear to be minor and not widely applicable if a mine operator chooses to use the construction general permit as opposed to the MSGP.

Upcoming: utility coal ash, groundwater/NPDES

Pending government startup


HB 1113: Eliminates self-bonding. Requires established date to end water treatment (and requires water treatment financial assurance) prior to mine plan approval.

NWMC / SME Conference, Denver, February 24-27, 2019. Still taking conference sponsorships.

Next water quality committee meeting, February 21, 9:00 – 10:00

Division of Reclamation Mining and Safety

Army Corps of Engineers