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 1002-35.31 - STATEMENT OF BASIS SPECIFIC STATUTORY AUTHORITY AND PURPOSE DECEMBER 2009 RULEMAKING REGARDING TEMPORARY MODIFICATIONS; FINAL ACTION FEBRUARY 8, 2010; EFFECTIVE DATE JUNE 30, 2010

Current through Register Vol. 47, No. 5, March 10, 2024

The provisions of C.R S. 25-8-202 (1)(a), (b) and (2); 25-8-203; 25-8-204; and 25-8-402; provide the specific statutory authority for adoption of these regulatory amendments. The Commission also adopted in compliance with 24-4-103(4) C.R.S. the following statement of basis and purpose.

BASIS AND PURPOSE

Pursuant to the requirements in the Basic Standards (at 31.7(3)), the Commission reviewed the status of temporary modifications to determine whether the temporary modification should be modified, eliminated or extended.

Ammonia: Temporary modifications of ammonia standards were reviewed.

Deleted: Ammonia temporary modifications were deleted on the following segments because permits had recently been reissued for dischargers on the segments. Compliance schedules in the permits are adequate to address any necessary treatment plant upgrade issues.

Uncompahgre River Segments 4a and 4

Lower Gunnison River segments 2

Detail added: Lower Gunnison River segment 4a: The following details were added to the tables: the chronic ammonia temporary modification was modified to clarify that the chronic standard's value is 0.02 mg/l, rather than just "TVS old"; and an expiration date of 12/31/2011 was added to the ammonia temperature temporary modification.

Other Parameters: Temporary modifications of other parameters were also reviewed.

Deleted: temporary modifications were deleted on the following segments because no permitted discharge has been identified that needs a temporary modification

Uncompahgre segment 4c selenium

Lower Gunnison segment 4b selenium

Detail added: An expiration date was added to tine temperature temporary modification on San Miguel River segment 4b

Extension of expiration dates: The Commission has decided to delay the basin-wide review of water quality classifications and standards for this basin until June 2012, to accommodate an issue-specific rulemaking for nutrient criteria in June 2011. Consistent with that decision, the expiration dates of the temporary modifications on the following segments that are currently scheduled to expire on 12/31/2011 are extended to 12/31/2012. These will be reviewed again in the December 2010 and December 2011 Temporary Modification hearing.

Upper Gunnison segments 8, 12, and 16

North Fork Gunnison segments 3, 5, and 6b

Uncompahgre segments 3a, 4b, and 12

Lower Gunnison segments 2, 4a (selenium only), and 7

San Miguel River segments 2, 3b and 4b

The Commission would like to emphasize that its intent and expectation is that the issues that necessitated adoption of these temporary modifications should be resolved as soon as possible and in a manner that takes full advantage of the opportunities provided by the December 2010 and December 2011 reviews of temporary modifications. The Commission recognizes that it is important to resolve uncertainty regarding the underlying standards so that temporary modifications can be eliminated and any needed pollution controls can be put in place in a timely manner.

PARTIES TO THE RULEMAKING