5 Colo. Code Regs. § 1002-34.34
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 in most cases 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. In other cases, no permits now discharge to this segment.
La Plata, etc segments 5a and 8a
Modified: La Plata, etc. segment 7a: The chronic ammonia temporary modification was modified to clarify that the chronic standard's value is 0.06 mg/l, rather than just "TVS old." "Type iii" was added to identify that there is significant uncertainty regarding the appropriate underlying standard. The expiration date was extended to 12/31/2012 to allow time for additional study.
Other Parameters: Temporary modifications for other parameters were also reviewed.
Deleted: Temporary modification were deleted on the following segment because no permitted discharge has been identified that needs a temporary modification.
La Plata, etc segment 3a iron
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.
San Juan segment 11a
Animas and Florida segments 2, 3a, 3b, 3c, 4a, 4b, 7, 8, and 9
La Plata, etc. segment 8a
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
5 CCR 1002-34.34