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 24-4-103(4), C.R.S., the following statement of basis and purpose.
BASIS AND PURPOSE:
The changes to the designation column eliminating the old High Quality 1 and 2 (HQ1, HQ2) designations, and replacing HQ1 with Outstanding Waters (OW) designation were made to reflect the new mandates of section 25-8-209 of the Colorado Water Quality Act which was amended by HB 92-1200. The Commission believes that the immediate adoption of these changes and the proposals contained in the hearing notice is preferable to the alternative of waiting to adopt them in the individual basin hearings over the next three years. Adoption now should remove any potential for misinterpretation of the classifications and standards in the interim.
In addition, the Commission made the following minor revisions to all basin segments to conform them to the most recent regulatory changes:
1. The glossary of abbreviations and symbols were out of date and have been replaced by an updated version in section 3.6.6(2).2. The organic standards in the Basic Standards were amended in October, 1991, which was subsequent to the basin hearings. The existing table was based on pre-1991 organic standards and are out of date and no longer relevant. Deleting the existing table and referencing the Basic Standards will eliminate any confusion as to which standards are applicable.3. The table value for ammonia and zinc in the Basic Standards was revised in October, 1991. The change to the latest table value will bring a consistency between the tables in the basin standards and Basic Standards.4. The addition of acute un-ionized ammonia is meant to bring a consistency with all other standards that have both the acute and chronic values listed. The change in the chlorine standard is based on the adoption of new acute and chronic chlorine criteria in the Basic Standards in October, 1991. Finally, the Commission confirms that in no case will any of the minor update changes described above change or override any segment-specific water quality standards.
38 CR 03, February 10, 2015, effective 6/30/201539 CR 03, February 10, 2016, effective 3/1/201639 CR 03, February 10, 2016, effective 6/30/201640 CR 03, February 10, 2017, effective 6/30/201741 CR 01, January 10, 2018, effective 1/31/201841 CR 03, February 10, 2018, effective 6/30/201841 CR 17, September 10, 2018, effective 12/31/201842 CR 04, February 25, 2019, effective 6/30/201943 CR 03, February 10, 2020, effective 6/30/202044 CR 05, March 10, 2021, effective 6/30/202144 CR 17, September 10, 2021, effective 12/31/202145 CR 17, September 10, 2022, effective 9/30/202246 CR 10, May 25, 2023, effective 6/14/2023