Code of Colorado Regulations
1000 - Department of Public Health and Environment
1002 - Water Quality Control Commission (1002 Series)
5 CCR 1002-35 - REGULATION NO. 35 - CLASSIFICATIONS AND NUMERIC STANDARDS FOR GUNNISON AND LOWER DOLORES RIVER BASINS
Section 5 CCR 1002-35.23 - STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY AND PURPOSE (June, 1997 hearing)
Current through Register Vol. 47, No. 17, September 10, 2024
The provisions of 25-8-202 (1)(a), (b) and (2), 25-8-203; 25-8-204; and 25-8-402 C.R.S. provide the specific statutory authority for adoption of these regulatory amendments. The Commission also adopted, in compliance with 25-4-103(4) C.R.S. the following statement of basis and purpose.
BASIS AND PURPOSE
1. Resegmentatlon
Extensive renumbering of segments was made throughout the basin due to information which showed that:
2. Wetlands
In March, 1993, the Commission amended the Basic Standards and Methodologies for Surface Water, Regulation 31 (5 CCR 1002-31) to include wetlands in the stream classification and standards system for the state. Due to that action, it became necessary to revise the segment description for all segments of the "all tributary" type to clarify that wetlands were also part of the tributary system for a given mainstem segment. All tributary wetlands now clearly carry the same classifications and standards as the stream to which they are tributary as provided for in 31.13(1)(e)(iv).
Information was submitted in the hearing that the Water Quality Control Division has been working with the Colorado Geological Survey to develop methodologies to measure the functions of wetlands. The development of such methodologies is an important implementation issue with respect to water quality standards for wetlands and the supports the Division's efforts in this regard.
3. Manganese Standards
On all segments classified for water supply and aquatic life uses, the total recoverable manganese standard of 1,000 ug/l was stricken. The aquatic life manganese criterion was changed in 1991 revisions to the Basic Standards from total recoverable to dissolved and on these segments a more stringent dissolved manganese water supply standard of 50 ug/l is in place. On segments classified for aquatic life and not water supply, the 1000 ug/l standard is designated as dissolved.
4. Mercury Standard
The Basic Standards include tine note tinat tine standard for mercury is based on tine Final Residual Value (FRV), and that mercury in the total form is the proper way to express that value. Therefore, the Commission decided to change the (TREC) notation for mercury to (tot) in all cases where it appeared.
5. Conversion to Dissolved iVIetais
Several segments in the previous version of the classifications and standards for these basins contained standards for metals as "total recoverable". The Commission previously determined that standards for most metals should be expressed as dissolved, necessitating conversion of those metals standards for the following segments:
Upper Gunnison Basin segments 11 and 12 (previously segments 12 and 13; temporary modifications for total recoverable metals deleted), 29 (previously segment 31).
Uncompahgre River segments 2, 3, 7, 8, and 9.San Miguel River segments 2, 3a, 3b, 6a, 6b, 7a and 8.
6. Clianges Necessary to Compiy witli "Swimmabie" Requirements
The Commission has reached an understanding with EPA regarding the classification and standards necessary to comply with the goal established in the federal Clean Water Act that all waters of the nation be suitable for recreation in and on the water. In Colorado, that requirement translates into a Recreation, Class 1, with the 200 fecal coliform/100 ml standard wherever swimming, rafting, etc. are in place or have the potential to occur; Recreation, Class 2, with 200 fecal coliform/100 ml standard wherever secondary contact recreation only is practiced, and the existing quality supports a class 1 recreation use and with consideration of the lack of significant increased treatment costs; and Recreation, Class 2, with the 2000 fecal coliform/100 ml standard in most other situations. This policy has resulted in recreation classification and/or fecal coliform standard modifications to the following segments:
Upper Gunnison Basin segments 4, 5, 6a and 6b (previously 6b and 6c), 7, segments 8 through 12 (previously 9 through 13), segments 16 through 19 (previously 17 through 20), segments 21 through 24 (previously 22 through 25), segment 26 (previously 27), segments 28 through 30 (previously 29 through 31), and segment 32 (previously 33).
North Fork Gunnison segment 2.
Uncompahgre River segments 3, 5, 7, 8, 9 (previously 9a), 13, and 15.
Lower Gunnison River segments 6, 7, 8, and segments 10 and 11 (previously North Fork segments 8 and 9).
San Miguel River segments 3b, 4, 5, and 8.
Dolores River segments 4 and 5 (previously 5 and 6).
Concerns were raised in this hearing regarding the potential impact of more stringent fecal coliform standards on agricultural and ranching practices. Ranching and agriculture have been extensive in the Upper Gunnison River Basin. The Upper Basin Parties submitted testimony that these uses date back to the late 1800s and have been a continuing integral economic and social factor in the basin. The Commission recognizes the extent of this use of land within the basin, and that ranching and agriculture have co-existed with a high level of water quality in the basin. The Commission summarizes the extent of agricultural and ranching use within the basin as a helpful baseline should issues involving compliance with fecal coliform standards in the future involve agricultural and ranching activities.
The testimony submitted indicates that the large majority of water rights and uses within the basin are decreed for agricultural uses. There are approximately 1,500 absolute ditch rights within the basin decreed only for agricultural and irrigation uses, representing total decreed diversions of more than 7,700 c.f.s. As of 1997, the following acreage was classified within the basin as agricultural for taxing purposes:
County Acres
Gunnison 343,742
Hinsdale 7,292
Saguaclne 54,299
Tine testimony also indicated that the Colorado Agricultural Statistics Service census of 1992 shows the total number of cattle and calves in Gunnison County as 30,713 head, and the Service estimates the total number as of January 1, 1997, was 31,343. The BLM reports there are 85 grazing permeates and 45,133 AUMs within its Gunnison Resource Area. The Forest Service reports that within its Taylor River Ranger District, there are 29 active allotments, encompassing 688,260 Forest Service acres, and a total number of 9,119 permitted livestock, and 8,893 of authorized livestock. Within the Cebolla Ranger District, the Forest Service reports there are 36 active allotments encompassing 552,529 acres, and a total number of 12,662 permitted livestock, and 13,395 authorized livestock.
The Commission finds that this degree of agricultural activities in the Gunnison Basin has existed in this region while the fecal coliform levels have been maintained at lower concentrations than the more stringent fecal coliform standards being adopted for a number of stream segments, as described above.
The Commission has previously stated that the fecal coliform standard is to be implemented with a rebuttable presumption that high densities of fecal coliform identified in water quality samples are due to human fecal pollution. The focus of the existing regulatory system for bacteriological parameters is on identifying and controlling sources of human waste that may be discharged to waters of the state without adequate treatment.
Parties to the hearing also proposed that the Commission adopt "an additional indicator that would distinguish between human fecal coliform and animal fecal coliform." Based on the information submitted, it does not appear that any such indicator is available at this time.
7. Upgrading of Class 2 Aquatic Life Segments
The Commission decided to adopt upgraded classifications and/or a more complete set of standards for several segments where the Division recommended such changes based on recent sampling of the biota by the Division of Wildlife (DOW) and the Water Quality Control Division. In general, these segments were previously thought to contain very little aquatic life, and were appropriate for the Class 2, minimal standards application found on most intermittent streams. However, the biological data referred to above indicated that a more diverse and rich aquatic life community existed, including threatened species. The Commission has chosen to recognize these facts by the adoption of a higher aquatic life classification and/or a complete set of protective standards. The segments/streams affected are:
Uncompahgre River segment 15.
Lower Gunnison River segment 9.
In addition, based on testimony by the Division of Wildlife, several specific creeks that had been included in segments with minimal standards were moved to segments with the usual aquatic life table value standards. These creeks are now located in:
Upper Gunnison segment 6b.
Uncompahgre segment 11.
San Miguel segment 10.
Lower Dolores segment 5.
8. Full Standards Not Applied to Aquatic Life Segments
EPA raised the issue of winy tine full set of inorganic aquatic life protection standards were not applied to various segments recommended for aquatic life class 2 classification. These segments typically were assigned only dissolved oxygen, pH, and fecal coliform standards. It was EPA's position that if there were dischargers located on the segments with the potential to produce toxic levels of one or more of the pollutants not contained in the abbreviated list of standards, the aquatic life in the segment could be jeopardized. Rather than adopt the full set of inorganic standards, the Commission was persuaded by the Division's arguments that the abbreviated list of standards was sufficient to protect the rudimentary aquatic life found in these intermittent streams, and that there was a very low probability that any of the few dischargers located on these segments would discharge toxic effluents. The segments where this policy was followed are:
Upper Gunnison Basin segments 6a, 13 (formerly 14), 15 (formerly 16), 27 and 31.
North Fork Gunnison segment 6.
Uncompahgre River segments 6, 10, and 12.
Lower Gunnison River segments 4, and 12.
San Miguel River segment 12.
Dolores River segment 3.
As noted above, where specific creeks within these segments were identified with aquatic life that warrants additional standards, they were moved into segments with the usual aquatic life table value standards.
9. Outstanding Waters Designations
The Commission followed the recommendations of the Division in assigning the Outstanding Waters (OW) designation to all waters covered by this regulation that are within the La Garita, West Elk, Collegiate Peaks, Maroon Bells, Ragged, Oh-Be-Joyful, Big Blue, Mt. Sneffels, and Lizard Head wilderness areas. Division water quality data indicated all antidegradation parameters to be well within table values and several of the wilderness waters provided habitat to ecologically significant specifies, i.e. Colorado River cutthroat trout and the boreal toad.
Uncompahgre River segment 1.
North Fork Gunnison segment 1.
San Miguel River segment 1. (Waters of the Sneffels Wilderness Area within the San Miguel watershed were added to Segment 1.)
The Commission also rejected a proposal by the High Country Citizens' Alliance (HCCA) and Western Slope Environmental Resource Council (WSERC) to adopt an outstanding waters designation for Upper Gunnison segment 25 and Lower Gunnison segment 1. These segments-which include Blue Mesa, Morrow Point and Crystal Reservoirs, as well as the Black Canyon of the Gunnison and the Gunnison Gorge-are located downstream of significant development in the Gunnison Basin and include reservoirs that are actively managed for a variety of purposes. The Commission does not believe that a showing has been made that adoption of the outstanding waters designation is necessary and appropriate for these waters at this time. The Commission is receptive to hearing future proposals regarding the adoption of outstanding waters designation or other forms of extra protection for these waters, supported by additional research and information regarding the implications of such protection for other activities in or upstream from such segments, particularly if broad support for any such proposals can be developed.
10. Use-Protected Designations
In a previous "Basic Standards" rulemaking, tine Commission cinanged tine basis for assigning tine use-protected designation by eliminating the automatic assignment where recreation class 2 was a classified use. In this comprehensive review of the basin classifications, designations, and standards, the Commission removed one use-protected designation in order to be consistent with that Basic Standards revision. This segment is:
Upper Gunnison Basin segment 10 (previously segment 11).
In addition, the Commission added the use-protected designation to several segments that met the criteria for use-protected. These are:
Uncompahgre River segments 6, 7, 8, 9, and 15.Lower Gunnison River segment 9.
The Commission also rejected a proposal by HCCA and WSERC to remove the use-protected designations for several other stream segments. In each instance, the segments in question are classified as aquatic life class 2. The Basic Standards and Methodologies for Surface Water provide that this classification requires a use-protected designation, unless the Commission determines "that those waters with exceptional recreational or ecological significance should be undesignated, and deserving of the protection afforded by the antidegradation review provisions." Section 31.8 . The evidence submitted in this hearing was not adequate to support such a finding.
11. Ambient Quaiity-Based Standards
The Division presented extensive information in its Exhibit 1 regarding ambient chemical quality of many segments in the basin. In most cases ambient quality was well within the "table value" limits prescribed by the Basic Standards for the protection of the various classified uses, prompting the Commission to assign those table values as segment standards. In a few cases, however, ambient quality exceeded the table values, yet there was information to suggest that the use was in place nonetheless. The available information lead to the conclusion that there was little hope of reversing the cause for degradation within twenty years. In those instances, the Commission followed the recommendation of the Division to adopt the 85th percentile of the ambient data as the standard (ambient quality-based standard). The following is a list of those segments where such standards have been adopted:
Upper Gunnison Basin segments 10, 11, 12 (formerly 11, 12, and 13) and 31. North Fork Gunnison segment 4. Uncompahgre River segments 2, 3, 4, and 7.
EPA expressed concern in the hearing regarding the basis for adopting ambient quality-based water quality standards. The Commission encourages the Division to work with EPA to explore the potential for developing more standardized criteria for determining that such standards are appropriate on a site-specific basis.
12. Temporary iVIodifications
In several instances, the Commission decided to establish temporary modifications to table value standards as an alternative to establishing an ambient-based standard. This practice was followed where these was information to suggest the underlying standard could be met within three years to five years, or where there were questions surrounding the data which could be clarified with additional sampling. Temporary modifications adopted for several segments for selenium standards are discussed separately below. The segments where other temporary modifications were established or modified are:
Upper Gunnison segment 8. Uncompahgre segment 4.
Lower Gunnison River segment 9.
San Miguel River segments 3a and 3b. (See separate discussion below.)
13. Water + Fish Organics Applied to Aquatic Life Segments
It is the policy of the Commission to establish the water+fish organics standards found in the Basic Standards for those Class 2 aquatic life segments where fish of a catchable size and which are normally consumed are present and there is evidence that angling takes place on a recurring basis. Based on these criteria and the testimony submitted, the Commission has chosen to assign the water+fish organics standards to the following class 2 aquatic life segments:
Uncompahgre River segments 4, 9 and 13. Lower Gunnison River segments 7 and 8.
14. Seienium Standards
In October of 1995, the Commission promulgated new aquatic life table value standards (TVS) for selenium, i.e., 20 ug/l acute and 5 ug/l chronic. At that time, the Commission adopted a footnote to the TVS which acknowledged that "selenium is a bioaccumulative metal and subject to a range of toxicity values depending upon numerous site-specific variables." The simultaneously adopted Statement of Basis and Purpose further elaborated upon this point, indicating that there exists the opportunity to develop "ambient or site-specific water quality standards on a basin-by-basin or specific segment basis," and identifying a number of site-specific factors that may be pertinent in the establishment of appropriate standards. Finally, the Commission noted that "a selenium standard need not be adopted during the course of triennial or segment specific rulemakings unless it is determined that the discharge or presence of selenium in the affected waters reasonably could be expected to interfere with the classified uses .. .."
In this basin-specific rulemaking, the Commission has decided to adopt the selenium TVS for most segments in the Gunnison and Lower Dolores basins. Temporary modifications, however, based on the 85th percentile of ambient data with an underlying TVS of 5 µg/l chronic and 20 µg/l acute, have been adopted for the segments identified below.
Uncompahgre River Segment 4.
Uncompahgre River Segment 14 (Sweitzer Lake).
Lower Gunnison River Segment 2.
North Fork Gunnison River Segment 5.
The Commission may revisit the question of ambient standards at some point in the future.
The Commission is hopeful that adoption of temporary modifications for these four segments will assist in reducing the existing high selenium levels. This action will establish interim goal-based criteria for selenium on these segments, ensure that there will be no further increases in selenium concentration for these waters as a result of regulated sources, and provide a mechanism to spur progress in improving water quality and attaining the goal-based standard. Furthermore, the temporary modifications may assist the Division in writing NPDES permits for any point source discharges while restoration efforts for nonpoint sources of selenium are unden/vay - the temporary modification will serve as the basis for calculating the interim effluent limits for such permits.
Most important, however, the temporary modifications provide a mechanism to address the existing high selenium concentrations in these segments. For example, adoption of temporary modifications will allow these segments to be listed pursuant to Clean Water Act (CWA) section 303(d) and section 305(b) -sections of the Act which require identification of water quality-limited segments. These listings, in turn, will increase the potential for funding for selenium control projects. Although it may become necessary to further revise the selenium numeric standards as additional information becomes available, it is hoped that this action will benefit efforts aimed at reducing the existing high selenium levels in these four segments.
In adopting the above standards and temporary modifications, the Commission took into consideration a number of factors, including statements from EPA and the USFWS that an ambient standard for the above-referenced segments may not be approved by EPA because of concerns over (i) the potential impacts of such an elevated concentration upon fish and wildlife, with specific reference to the federally listed endangered species in the Lower Gunnison River Segment 2; (ii) the need for EPA to meet its consultation responsibilities under Section 7 of the Endangered Species Act; and (ill) the uncertainty as to whether the present condition is reversible.
The Commission acknowledges that there is also uncertainty associated with what will eventually prove to be the appropriate selenium standard for segments in this basin. For example, EPA is currently reexamining its national criteria for selenium. The USFWS is completing additional work on the potential impact of selenium upon razorback suckers, with a final report due in early 1998. Additional work is also being performed upon perfecting site specific methods of standard determination, including a sediment-total organic carbon model and uptake of selenium in aquatic biota.
Additional uncertainties presently exist concerning (i) the relative contributions of varying sources to the existing high ambient levels; (ii) whether these levels can be significantly reduced within 20 years or, stated another way, the pace of restoration efforts; (ill) what BMPs or other treatment technology exists or may be developed in the near future to achieve such a reduction; and (iv) the extent of measurable improvements in the aquatic ecosystem if the underlying TVS of 5 ug/l chronic is achieved.
Furthermore, it is currently unknown whether adequate funds can be found to undertake prevention and remediation measures, with specific reference to the control of nonpoint sources of selenium loading. The interested parties, together with the EPA, USFWS, and the Division shall cooperate in identifying sources of funds and, to the extent possible, obtaining needed monies, including funds which may be available under Section 319 of the Clean Water Act, from the US Department of Agriculture pursuant to the Environmental Quality Improvement Program (EQIP), the US Bureau of Reclamation through the Colorado River Salinity Control Program or the US Department of Interior through the Irrigation Drainage Program. The EPA, USFWS, and the Division, in their testimony, agreed to express to the Colorado River Basin Salinity Control Forum, in writing, their position that salinity control projects which simultaneously reduce loading should receive funding priority.
The interested parties to the hearing, the federal agencies, and landowners in the vicinity of the affected reaches have expressed an interest in employing voluntary, cooperative prevention and remediation practices for purposes of reducing selenium loading and improving water quality. The Commission encourages the formation of a Task Force for this purpose, and urges the Division to cooperate in such an effort. This Task Force could employ the TMDL concept in seeking to achieve the underlying TVS for selenium.
The Division has indicated to the Commission that it may take a minimum of five years to identify, fund and implement selenium control projects in these basins which may measurably improve water quality in the segments of concern. Thus, though the segments with a temporary modification will be reviewed at the end of three years, it is not anticipated that there will be any significant changes at that time.
15. Site-Specific Issues
In response to a proposal by Climax Molybdenum Company (CMC), the Commission has adopted ambient quality-based standards for several metals for Coal Creek, segments 11 and 12 of the Upper Gunnison Basin (formerly segments 12 and 13). CMC submitted evidence that elevated metals levels in these segments are caused by "natural or irreversible man-induced" impacts. In adopting these standards, the Commission recognizes the following agreements between the parties with respect to these segments:
CMC agrees to assist HCCA in performing a reconnaissance study consisting of physical surveillance and high flow and low flow water quality monitoring in segment 11 with the objective of identifying sources of Cd, Fe, Mn and Zn.
CMC agrees to work with other parties, which may include the Town of Crested Butte and Gunnison County, to pursue development of a remedial project (or projects) to be funded by the section 319 nonpoint source grant program if such project (or projects) appear feasible.
HCCA agrees to support the adoption of the ambient based standards proposed by CMC for segments 11 and 12.
Homestake Mining Company expressed concern about the Division's initial proposal to eliminate separate segments for Indian Creek (formerly Upper Gunnison segments 21a and 21b) and to add these waters into the segment for Marshall Creek (formerly Upper Gunnison segment 22). Following consideration of the evidence, including an agreement between the Division and Homestake, the Commission has left the upper portion of Indian Creek (formerly segment 21a, now segment 20) as a separate segment. The lower portion of Indian Creek (formerly segment 21 b) has been added to the Marshall Creek segment (formerly segment 22, now segment 21).
The Commission considered a proposal by HCCA and WSERC to move the segment boundary between North Fork segments 2 and 3 further downstream, to account for primary contact recreation activities in the upper portion of segment 3 as previously defined. The evidence does demonstrate that primary contact recreation uses currently occur in these waters. Following an extensive discussion of alternative potential resegmentation options, the Commission has established the new segment boundary at the Black Bridge, on which 4175 Drive crosses the river. The evidence indicates that the majority of the primary contact recreation use occurs above that point.
In response to a proposal by the Division, the Commission has established a new segment for Fruitgrowers Reservoir-segment 9 in the Lower Gunnison Basin. The evidence demonstrates that aquatic life class 2, recreation class 1 and agriculture are appropriate classifications for this reservoir based on actual current or recent past uses of these waters. In view of the reservoir's current degraded quality, the Commission has adopted a goal qualifier for the recreation classification and temporary modifications for the un-ionized ammonia and fecal coliform standards. The Commission appreciates and wishes to encourage the efforts of interested entities in the area to undertake a cooperative, intergovernmental two-year study to better determine the cause of current water quality problems in the reservoir. The Commission requests that the Division provide to the Commission an update regarding the status of these study efforts in the fall of 1998.
The extensive data submitted in evidence demonstrate tinat tine zinc levels in San Miguel River segments 3a and 3b exceed the current numeric standard of 190 ug/l of dissolved zinc (chronic) applicable to both segments. It is unclear whether that standard can be met within 20 years. Under a 1992 Consent Decree with the State of Colorado, Idarado Mining Company is pursuing activities pursuant to a Remedial Action Plan ("RAP") to remediate historic mining impacts in the upper reaches of the San Miguel River and Red Mountain Creek drainages, in order to enhance water quality. One performance objective of the RAP is to reduce zinc levels at a compliance point within San Miguel River segment 3b to 276 µg/l of dissolved or 336 ug/l of total zinc, on an average annual basis. The Commission will review the appropriateness of the 190 ug/l dissolved zinc (chronic) standard for segments 3a and 3b in future rulemakings to assess whether it should be adjusted to reflect actual water quality achievable and the uses that are attainable in light of Idarado's remediation efforts. In addition, five-year temporary modifications of 410 ug/l and 640 ug/l for dissolved zinc in segments 3a and 3b, respectively, to reflect ambient water quality are justified in light of the anticipated water quality enhancement resulting from Idarado's actions, and to coincide with the start of the compliance period under the RAP. Nothing in this rulemaking is intended to adjust, modify, or abrogate the Consent Decree or RAP.
In response to a request by HCCA and WSERC, the Commission has added a water supply classification, and corresponding numerical standards, to the following three segments:
Upper Gunnison segments 8 (formerly 9) and 15 (formerly 16).North Fork segment 6.
In each case, evidence was submitted that alluvial ground water hydrologically connected to these surface waters is used through domestic wells as a water supply. For Upper Gunnison segment 8, the Commission also adopted temporary modifications for iron and manganese, in view of evidence that current levels of these constituents are elevated above table values.
16. Other Proposals
EPA expressed concern in the hearing regarding whether documentation had been provided of an adequate "use attainability analysis" for segments whose classifications do not achieve the "fishable, swimmable" goals of the federal Clean Water Act. Based on the information provided, the Commission has adopted the Division's proposals for the waters in question. The Commission encourages the Division to work with EPA to assure that adequate documentation of the Division's use attainability analysis conclusions has been provided.
HCCA and WSERC requested that the Commission take action in this hearing to prohibit future in-stream gravel mining. The Commission has determined that this proposal is not relevant to the water quality designation, classification and standards issues raised in this hearing.
