5 Colo. Code Regs. § 1002-32.24

Current through Register Vol. 47, No. 20, October 25, 2024

Section 5 CCR 1002-32.24 - STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY AND PURPOSE: AUGUST 14, 1995 HEARING

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 adopted, in compliance with 25-4-103(4) C.R.S. the following Statement of Basis and Purpose.

BASIS AND PURPOSE

INTRODUCTION:

The amendment to the Classifications and Numeric Standards for Arkansas River Basin, 3.2.0 (5 CCR 1002-8) are the result of the second in a series of comprehensive basin reviews of Colorado's stream classifications and standards. The Commission has established a schedule to continue these comprehensive reviews until all seven basins have undergone a thorough review using current data supplied through the Division's concentrated basin monitoring program, supplemented by USGS and other current data.

In the process of revising the classifications, designations, and standards for the Arkansas basin, the Commission relied heavily on the data and analysis supplied by the Division in its Exhibit 1. Where reference is made to the Division's recommendations in this statement, that reference is to Division Exhibit 1 unless specifically noted otherwise. Several parties to the hearing also supplied data and recommendations which the Commission used in arriving at a final set of classifications and standards and those sources are referenced as appropriate. The organization of this statement first addresses those general issues applicable to most or all segments, followed by a discussion of decisions applicable to individual segments.

GENERAL ISSUES:

1.Resegmentation: Extensive renumbering of segments was made throughout the basin due to information which showed that:

a. The original reasons for segmentation no longer applied.

b. New water quality data showed that streams should be resegmented based on changes in their water quality.

c. Certain segments could be grouped together in one segment because they had similar quality and uses.

Rather than list here all the resegmentation that was made, the reader is advised to contact the Division if there are questions as to which streams are found in which segment descriptions.

2.Wetlands: In March, 1993, the Commission amended the Basic Standards and Methodologies for Surface Water 3.1.0 (5 CCR 1002-8) 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 3.1.13(1)(e)(iv).

3.Conversion to Dissolved Metals: Several segments in the previous version of the classifications and standards 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 for the following segments:

Upper Arkansas, segments 1b (temporary modifications for total recoverable metals deleted), 7, 8a1, 8b, 9 and 11.

Fountain Creek, segment 1.

4.Changes Necessary to Comply with "Swimmable" Requirements: The Commission has reached an understanding with EPA regarding the classification and standards necessary to comply with the requirements contained 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 FC/100 ml standard wherever secondary contact recreation only is practiced, and the existing quality supports a class 1 recreation use and little or no impact to dischargers will result; and Recreation, Class 2, with the 2000 FC/100 ml standard in most other situations. This policy has resulted in recreation classification and/or coliform standard modifications to the following segments:

Upper Arkansas, segments 1b, 2a, 2b, 2c, 3, 5, 7, 8a, 8b, 9, 10, 11, 16b, 17b, 21, and 27.

Middle Arkansas, segment 3.

Fountain Creek, segments 1 and 6.

Lower Arkansas segments 1, 5a, 7, 9a, 9b, 9c, 13.

Cimarron River, segment 2.

The detailed rationale for these changes is found in WQCD Exhibit 1. A more complete basis and purpose for those segments where these changes were controversial is found in the segment-by-segment discussion which follows these general issues.

5.Upgrading of Class 2 Aquatic Life Segments : The Commission decided to adopted upgraded classifications and/or a more complete set of standards for several segments where the Division recommended same 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 plains 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 streams so affected are:

Middle Arkansas.	segment 10; Sixmile Creek
.	segment 18; Rush and Boggs Creeks
Lower Arkansas,	segment 9a; Rush Creek and forks, Antelope Creek, Horse Creek, West May Valley Drain
.	segment 9b; Apache Creek, Breckenridge Creek, Little Horse Creek, Bob Creek, Cheyenne Creek, Wildhorse Creek, Buffalo Creek, Wolf Creek, Big Sandy Creek
.	segment 9c; Rule Creek, Muddy Creek, Caddoa Creek, Clay Creek, Cat Creek, Two Butte Creek, Trinchera Creek, Mustang Creek, Chicosa Creek, Smith Canyon
Cimarron River,	segment 2; North Carrizo Creek, East and West Carrizo Creeks, Cottonwood Creek, Tecolote Creek

6.Arsenic Standard: On all segments where arsenic was shown as "As(ac/ch)=TVS", the Commission changed the standard to read "AS(ch)-100(Trec)". This change was made because the Basic Standards (3.1.0) lists a lower Table Value Standard for agricultural use classification than the chronic aquatic life standard. Where water supply is a classified use, the Table Value Standard of 50 ug/l was retained since it was more restrictive.

7.Manganese Standard: 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.

8.Mercury Standard: The Basic Standards include the note that the standard for mercury is based on the 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.

9.Selenium Standard: The Commission revised the selenium water supply use criterion in the Basic Standards from 10 ug/l (Trec) to 50 ug/l (dis) in 1994. As a result, the chronic aquatic life criterion is now more stringent than the water supply value. In this action, the Commission decided to replace the old 10 ug/l standard with the TVS for aquatic life, namely "Se(ac/ch) = TVS" on all segments assigned a full set of standards for the protection of aquatic life.

10.Use Protected Designation: In a previous rulemaking, the Commission changed the basis for assigning the Use Protected designation by eliminating the automatic assignment where Recreation Class 2 was a classified use. In this comprehensive review of the Arkansas basin classifications, designations, and standards, the Commission revised several segment designations in order to be consistent with that Basic Standards revision. Those segments are:

Middle Arkansas	Segment 3; Arkansas River mainstem through Pueblo.
.	Segment 14; Cucharas River from la Veta to Cuchara Reservoir.
Lower Arkansas	Segment 9a; Various small tributaries to the lower Arkansas River.
.	Segment 13; Various reservoirs and ponds in the lower Arkansas basin.

11.Ambient-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 limits prescribed by the Basic Standards for the protection of the various classified uses, prompting the Commission to assign those Table value standards 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-based standard). Division Exhibit 1 explains the basis for these ambient-based standards in detail, but the following is a list of those segments where such standards have been adopted:

Upper Arkansas, Segments 8b, 10, 11, and 19.

Middle Arkansas, Segments 5, 7, and 12.

Fountain Creek, Segments 2, 6.

Lower Arkansas, Segments 1 and 4.

12.Temporary Modifications: 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, or where there were questions surrounding the data which could be clarified with additional sampling The segments where temporary modifications were established of modified are:

Upper Arkansas, Segments 1b, 2b, 2c, 9, 20, and 22.

A more complete rationale for the establishment of these temporary modifications for several of the segments listed above is found in the segment specific discussion which follows this general issues discussion.

13.Full Standards Not Applied to Aquatic Life Segments: EPA raised the issue of why were the full set of inorganic aquatic life protection standards 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 in Exhibit 1 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 Arkansas, Segments 14 and 26.

Middle Arkansas, Segments 4 and 15

Fountain Creek, Segment 4

Lower Arkansas, Segments 2 and 6b

Cimarron, Segment 1

14.Water + Fish Organics Not 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 there is evidence that angling for edible species is at least occasionally practiced. No party, including the Division and Dow, produced such evidence at this hearing. Therefore, the Commission has chosen not to assign the Water+Fish organics to any of the Class 2 Aquatic life segments.

15.Ambient-Based Selenium Standards: The Commission decided to establish an ambient-based standard for selenium for Segment 2 of Fountain Creek and Segment 4 of the Lower Arkansas based on testimony of the Division in Exhibit 1. This action was taken with the understanding that the overall issue of the proper selenium standards for the state will be considered in an upcoming hearing, and that the proper methodology for establishing ambient-based selenium standards will also be a subject of that hearing. This action on two Arkansas basin segments is not intended to be definitive on the issue of selenium standards for the state, but rather, is merely a recognition of existing ambient conditions with respect to the current selenium Table Values.

16.Manganese Table Value for Agriculture Not Applied: EPA pointed out that the Commission has not proposed to include the Table Value for manganese of 200 ug/l for all segments in the Arkansas basin. The Commission was persuaded by the Division's arguments in its rebuttal statement that this table value was properly applied only to segments where site-specific information showed that acidic soils were under irrigation which might produce damaging levels of manganese.

SEGMENT-SPECIFIC ISSUES and DECISIONS:

UA, Segment 1a, Waters in the Mount Massive and Collegiate Peaks Wilderness Areas: The Commission followed the recommendations of the Division in assigning the Outstanding Waters (OW) designation to all waters in these wilderness areas. Division data showed all antidegradation parameters to be well within Table Values and the wilderness waters provided habitat to ecologically significant specifies i.e. greenback cutthroat trout and the boreal toad. There was no opposition voiced by the parties or the public.

UA, Segment 1b, East Fork of the Arkansas River: Cyprus Climax Metals Company, a party to this hearing, and the Division resolved differences on this segment through the preparation of a stipulated agreement regarding Water Supply Classification, various standards, and the deletion and addition of various temporary modifications. The Commission concurred with the stipulation and adopted the contents as a result. The Division's rebuttal statement contains a full explanation of the basis for the stipulation.

UA, Segments 2b, 2c, 6, Upper mainstem of the Arkansas River; California, St. Kevin's Gulch: Although not objecting to the specific proposal of the Division, Resurrection Mining asked that certain language in the Division's Exhibit 1 be resided. The Commission declined to make such changes reasoning that the Division had the right to draw up its testimony (Exhibit 1) as it so chose, and that if there was misinformation or errors in that testimony, the Commission would prepare a separate rationale for the action it took on the particular segments in question. For the segments in question by Resurrection, the Commission has not found any reason to prepare a rationale different from that prepared by the Division.

UA, Segment 3, Mainstem of the Arkansas River to Pueblo Reservoir: The Division of Wildlife asked that a pond (slough or oxbow lake) in Florence be separated out for classification to protect several important species which resided there. The Division testified that it considered that body of water part of Segment 3, the mainstem of the Arkansas, and would advise any regulatory program using the stream standards to base decisions affecting the pond on Segment 3 standards. With that understanding, the Commission decided not to separate out the pond, and rely on Division interpretation of Segment 3 description to protect the waterbody.

UA, Segments 19, 20, 21, and 22, Fourmile Creek, Cripple Creek, and Arequa Gulch: The Division, Cripple Creek and Victor Gold Mining (CC&V), agreed on segmentation, classification, temporary modifications, and standards for streams in the Cripple Creek area. "Citizens for Victor!" took a position that the standards should not be changed. Using the water quality data supplied by CC&V and commitments by CC&V to continue to monitor ambient quality, the Division and CC&V presented to the Commission a stipulated agreement on the segmentation, classifications, temporary modifications, and standards. Citizens for Victor! did not sign the stipulation. The Commission carefully considered the two positions and decided that because the TVS underlay the water quality parameters for which temporary modifications would expire and be reviewed in two years, the Division and CC&V proposal was the most appropriate in view of the uncertainties as to exactly how the water chemistry would change upon relocation of the tailings materials and the plans and commitments for operations and reclamation (through the mining and reclamation permit) of CC&V.

MA, Segment 3, Mainstem Arkansas River through Pueblo: The Division, City of Pueblo, Pueblo Waterworks, Pueblo West, and St. Charles Mesa all took various positions regarding the proper designation, recreation classification, aquatic life classification, and fecal coliform standard on the segment. Partial consensus was reached on the recreation classification, but the other issued remained for Commission decision. The Commission concluded that the proper designation was "reviewable" since the segment exhibited class 1 warm water characteristics and the quality was better than table values for all parameters. In addition, the Commission decided that 200 fecal coliforms/100 ml was appropriate since ambient quality met that level and no impact to dischargers would be felt with that standard in place. An additional factor in the coliform decision was the support that St. Charles Mesa had for the standard as additional protection for its water supply. The concerns from Pueblo and Pueblo West regarding possible financial impacts if the coliform standard and reviewable designation were adopted appeared speculative to the Commission.

MA, Segment 18, Warm Water Tributaries to the Arkansas River: Pueblo West took a position opposite that of the Division and DOW regarding the appropriateness of the aquatic life classification for the tributaries included in this segment. Pueblo West argued that not enough information was available to set the full set of standards recommended by the Division and Dow. The Commission felt there was sufficient rationale for the Division's recommendations, and adopted the classifications and standards accordingly. Dow asked that Rush Creek and Boggs Creek be included in Segment 18, and the Commission concurred.

FC, Segment 3, Tributaries to Fountain Creek on NF or USAF Lands: Colorado Springs asserted that the segment description as proposed by the Division was confusing and asked for clarification. After debating several alternatives for describing the segment, the Commission agreed upon a clarifying change.

FC, Segment 6, Monument Creek: The Division, Woodmoor, Donala, and USAF Academy had various positions regarding the appropriate recreation classification, coliform standard, and manganese standard for the mainstem of Monument below the National Forest boundary. As a result of meetings and conversations with the Division prior to the hearing, the parties decided not to oppose the Division's proposals for this segment. These parties intend to undertake additional monitoring to further assess the appropriateness of the standards for this segment. As a result, the Commission adopted the Division's recommendations as explained in Division Exhibit 1 for the segment.

LA, Segment 1, Mainstem Arkansas River to Kansas Line: The City of Pueblo recommended that the fecal coliform standard remain at 2000 FC/100ml for segment 1 because it was protective of the actual recreation uses of the segment and because there was a potential for economic impact to the city through increased wastewater treatment costs. The Division recommended the standard be lowered to 200 FC/100ml because of the agreed upon approach to meeting the "swimmable" goals of the Clean Water Act, because the segment met the 200 coliform limit, and because Pueblo's treatment plant appeared to easily meet low coliform levels in its effluent. After considering the two positions, the Commission agreed with the Division's recommendations and adopted the 200 FC/100ml standard.

The DOW asked that segment 1 (Fountain Creek to Kansas border) be resegmented at Nepesta, with a lowered ammonia standard of 0.06 mg/l (un-ionized) applied to the lower portion of the segment below Nepesta. Dow reasoned that several fish species in decline in the state were found in this reach, and that there was a correlation between high nutrient levels and the disappearance of these species elsewhere in the state. DOW also noted that the ambient levels of ammonia was consistently less than 0.06 mg/l unionized throughout the segment. The Division, City of pueblo, and CF&I Corporation disagreed with the DOW on the need for an ammonia standard lowered from the existing and proposed standard of 0.1 mg/l. They argued that DOW had not offered proof that ammonia was the cause for decline in these species anywhere, let alone in the lower Arkansas River and that a reduced ammonia standard could cause an economic impact on dischargers to that segment. The Commission shared the DOW's concern over the decline in certain native fish species in the state, but wanted further information regarding the cause for that decline before setting an ammonia standard which might cause financial hardship without clear benefit. Therefore, the Commission decided to continue with the 0.1 mg/l un-ionized ammonia standard with the understanding that in about one year, the Division and DOW would update the Commission on the status of the declining species and their sensitivity to ammonia, and on the true impacts to the dischargers on the segment. Based on the update, the Commission may at that time decide to reconsider the matter or continue with the 0.1 mg/l standard.

PARTY STATUS LIST/MAILING LIST STATUS AUGUST 14, 1995

1. The Cripple Creek & Victor Gold Mining Co.

2. Cyprus Climax Metals Co.

3. St. Charles Mesa Water District

4. The City of Pueblo

5. Resurrection Mining Co.

6. Colorado Division of Wildlife

7. City of Colorado Springs Water Resources Dept.

8. The Board of Water Works of Pueblo, Colorado

9. Pueblo West Metropolitan District

10. Citizens for Victor!

11. Woodmoor Water and Sanitation District

12. U.S. Environmental Protection Agency's Region VIII Office

13. CF&l Steel, L.P.

14. Donala Water and Sanitation District, Forest Lakes Metropolitan District and Triview Metropolitan District

15. Westplains Energy

16. Philip Voegtle

5 CCR 1002-32.24

38 CR 03, February 10, 2015, effective 6/30/2015

39 CR 03, February 10, 2016, effective 3/1/2016

39 CR 03, February 10, 2016, effective 6/30/2016

39 CR 23, December 25, 2016, effective 12/30/2016

40 CR 03, February 10, 2017, effective 6/30/2017

41 CR 01, January 10, 2018, effective 1/31/2018

41 CR 03, February 10, 2018, effective 6/30/2018

41 CR 17, September 10, 2018, effective 12/31/2018

42 CR 04, February 25, 2019, effective 6/30/2019

43 CR 03, February 10, 2020, effective 6/30/2020

44 CR 01, January 10, 2021, effective 2/14/2021

44 CR 05, March 10, 2021, effective 6/30/2021

44 CR 17, September 10, 2021, effective 12/31/2021

45 CR 17, September 10, 2022, effective 9/30/2022

46 CR 10, May 25, 2023, effective 6/14/2023