Revisions to Colorado Regulation 7, Part D Affecting Midstream Operations

In December 2021, the Colorado Air Quality Control Commission adopted a broad range of new regulations aimed at reducing emissions of greenhouse gas pollutants and ozone precursors, with emission reductions prioritized in disproportionately impacted communities (DIC). The regulations adopted covered several broad topic areas and spanned both Regulation 7 and Regulation 22.

This post is dedicated to the revisions adopted for Regulation 7 that affect Midstream Operations only:

• The latest full version of Regulation 7 can be found at the following link.
• A redline version of Regulation 7, showing all changes adopted in December 2021, can be found at the following link.

Leak Detection and Repair (II.E.)

Compressor Stations Inspection Frequency (II.E.3.)

• Beginning 1/1/2023
• Natural gas compressor stations with fugitive VOC emissions greater than zero (0) but less than or equal to 12 tons per year (tpy) (based on a rolling 12-month total) must conduct quarterly instrument monitoring inspections.
• Natural gas compressor stations located within a DIC, or within 1000 feet of an occupied area, must inspect components for leaks in accordance with the inspection frequency in Regulation 7 Table 3.
• The resulting compressor stations Leak Detection and Repair (“LDAR”) inspection frequencies are listed in Regulation 7 Table 3.
• Natural-gas driven pneumatic controllers must be inspected using Approved Instrument Monitoring Method (“AIMM”) at the same frequency as fugitive components.

Leak Repair Requirements (II.E.6-7)

• Beginning 2/14/2022, where technically feasible, emissions from leaks placed on delay of repair must be mitigated within no later than 48 hours of placing a leaking component on delay of repair.

Midstream segment pigging and blowdown requirements (II.H.)

Applicability of capture and recovery requirements

Pigging and blowdown operations at compressor stations and gas processing plants (II.H.1.)

In addition, for equipment not initially subject to these requirements, the requirements become effective within 60 days of the first day of the month for equipment which increases hydrocarbon emission levels to the above indicated thresholds after the applicable compliance date of the rule.

Pigging operations at standalone pigging stations (II.H.2.)

In addition, for equipment not initially subject to these requirements, the requirements become effective within 60 days of the first day of the month for equipment which increases hydrocarbon emission levels to the above indicated thresholds after the applicable compliance date of the rule.

Capture and recovery requirements (II.H.3.)

During normal operations (excluding planned emergency system shutdown testing operations), emissions from pigging and blowdown activities must be captured and recovered.  Blowdowns of storage vessels, pressure vessels, or process vessels operating below 20 psig are not required to be captured and recovered. Residual emissions from depressurization of the blowdown volume remaining after capture and recovery techniques have been implemented are considered in compliance.

Where a compressor station (“CS”) or a natural gas processing plant (“GP”) is connected to an electric grid, capture and recovery techniques must be powered by non-emitting equipment. If technically or economically infeasible, the operator must keep records of the determination made.

If capture and recovery of pigging/blowdown emissions is not feasible, an operator may request Division approval to use a control device to comply with this section. If such activities are controlled as of 2/14/2022, or if an application was pending with the Division as of 12/31/2021 to control such activities, then no further Division approval is required. The Division must be notified by 3/31/2022 that control devices will be used to comply with this section.

Midstream operators must design and operate CS, GP, and standalone pigging stations that commence operation on after 1/1/2023 to maximize capture and recovery of routine pigging/blowdown emissions and keep a record of the analysis undertaken at the time of facility development.

Required best practices (II.H.4.)

Beginning 1/1/2023, Midstream operators are required to use best practices for all pigging/blowdown operations at their facilities, including standalone pigging stations and midstream pipelines not located within the boundaries of a CS or GP. The following list highlights some (not all) of the required best practices:

• Utilizing liquids management system for pigging units in the Nonattainment Area (“NAA”)
• Rerouting gas to low pressure systems where feasible for pipeline blowdowns
• Using short pig barrels
• Planning for venting-reduction steps, such as pipeline pump-down techniques
• Coordinating operational repairs and routine maintenance

Natural gas processing plants requirements (II.I., III.C.3.d., III.D.4.)

Leak Detection and Repair (II.I.)

Beginning 1/1/2023, GPs not subject to the requirements in Regulation 7 Part D, Section I.G. must comply with New Source Performance Standard (“NSPS”) OOOOa LDAR requirements for GPs unless subject to NSPS OOOO requirements for GPs.

For leaks placed on delay of repair (“DOR”), operators must repair the leaks within two (2) years or the applicable timeline in NSPS OOOO or OOOO/a, whichever is earlier. The operator must also take action(s) to mitigate emissions from DOR leaks where technically feasible.

Natural gas-actuated pneumatic controllers (III.C.3.d., III.D.4.)

All pneumatic controllers, located at GPs not subject to the requirements of Section III.C.2 and placed in service on or after 1/1/2023, must be zero-bleed (unless allowed in Section III.C.3.a.iii).

All pneumatic controllers placed in service prior to 1/1/2023 at GPs must be replaced or retrofit with a zero-bleed option by 1/1/2024 (unless allowed in Section II.C.3.a.iii).

For all pneumatic controllers that remain in service at natural gas processing plants with a bleed rate greater than zero (0) for process/safety purposes, the operator must tag and inspect the controllers monthly beginning 3/1/2023. Additionally, the operator must submit a justification to the Division:

• By 3/1/2023 for pneumatic controllers that were placed in service prior to 1/1/2023
• 30 days prior to installation for pneumatic controllers placed in service on or after 1/1/2023

Beginning 1/1/2023, operators must inspect gas-driven pneumatic controllers at GPs at least quarterly using an approved instrument monitoring method.

Finally, beginning 5/31/2024, operators of GPs must submit annual reports regarding their pneumatic controllers’ inspection and enhanced response activities.