Greenhouse Gas Emissions and Energy Management for Manufacturing in Colorado


The Colorado Air Quality Control Commission passed a regulation for a Greenhouse Gas Emissions and Energy Management for Manufacturers In Colorado (GEMM) on October 22, 2021. The rule was effective starting December 15, 2021. This rule will help Colorado achieve the economy-wide goals to reduce 2025 greenhouse gas (GHG) emissions by at least 26%, 2030 GHG emissions by at least 50%, and 2050 GHG by at least 90% compared to Colorado's GHG emissions total in 2005. 

The GEMM rule requires facilities that show through an audit process they are using GHG Best Available Control Technologies and Energy Best Management Practices to achieve an additional 5% reduction in their GHG emissions.

House Bill 1266, passed in July, 2021, requires Colorado's manufacturing sector as a whole to reduce their emissions 20% by 2030, based on 2015 reported emissions, which will be addressed in a second phase of the GEMM rulemaking in 2022 and 2023. 

The rule applies to four facilities in Colorado: 

  1. EVRAZ Steel Mill in Pueblo
  2. Holcim-Portland Plant in Florence
  3. GCC Rio Grande in Pueblo 
  4. Cemex Construction Materials South in Lyons 



The facilities subject to GEMM must submit a GHG Best Available Emissions Control Technology and Energy BMP Audit Plan to the Air Division for review, describing which GHG emitting equipment will be audited and who will be on the audit team. The audit plan must comply with requirements as described in the GEMM rule and be approved by the Division prior to the audit. Current facility audit plans and Division approvals have been made available to the public below.

EVRAZ Audit Plan Documents

GCC Audit Plan Documents

GEMM Rule Information:

The final rule publication can be downloaded HERE and the GEMM Rule starts on page 209. 

GHG Emissions and Energy Management Audit Program Resources 

GEMM Auditor Selection: APCD Guidance Document 


If you have questions, please email, with GEMM in the subject line.