### Partner Reported Opportunities (PROs) 

## PRO Fact Sheet No. 601 for Reducing Methane Emissions



# Perform Valve Leak Repair During Pipeline Replacement

Technology/Practice Overview

Description Operating pipelines remain in service for long periods of time, during which they experience internal corrosion and significant pressure, thermal, and mechanical stresses. Corrosion debris will often accumulate in valve seats, preventing tight closure and causing gas leakage when the valves are closed to isolate pipeline sections for repair. Pipeline replacement or repair projects afford rare opportunities to inspect and maintain both internal and external components on pipeline valves since repairing valves would typically require the pipeline to be taken off-line. To cost effectively re duce gas losses, one Partner reports inspecting and repairing leaking components in the vicinity of ongoing pipeline repair or replacement projects. These inspections can be carried out efficiently using infrared cameras, acoustic leak detectors, and/or other leak detection devices.

Operating Requirements In order to perform leak repairs, clean valve seats, replace valve-stem packing, replace couplings, or remove and replace an entire valve, it is necessary to isolate it, which requires other mainline valves to be closed. Balloon seals may need to be inserted to isolate a valve for maintenance.

Applicability This practice applies to all pipeline repair and replacement projects.



### Methane Emissions

The amount of avoided emissions is based on the typical leak rates through

Estimated Gas Price Annual Methane Savings Value of Annual Gas Savings* Estimated Implementation Cost Incremental Operating Cost Payback (months)

$7.00/Mcf 2,500 Mcf $18,600 $3,000 $200 2 Months

$5.00/Mcf 2,500 Mcf $13,300 $3,000 $200 3 Months

$3.00/Mcf 2,500 Mcf $8,000 $3,000 $200 5 Months 

### Economic and Environmental Benefits

Economic Evaluation

Additional Benefits
 Safety of pipeline system and operators 

###  Timely repair can avoid future system upsets and unplanned shut-downs Estimated annual methane emission reductions 2,500 Mcf per ten pipeline gate valves 

### Methane Savings

* Whole gas savings are calculated using a conversion factor of 94% methane in pipeline quality natural gas. Compressors/Engines
Dehydrators
Directed Inspection & Maintenance
Pipelines

Pneumatics/Controls

Tanks

Valves

Wells

Other



### Applicable Sector(s)

Production Processing

Transmission

Distribution

Other Related Documents:

Test and Repair Pressure Safety Valves, PRO No. 602
Directed Inspection and Maintenance at Compressor Stations, Lessons Learned
Directed Inspection and Maintenance at Gate Stations and Surface Facilities, Lessons Learned
Directed Inspection and Maintenance at Gas Processing Plants and Booster Stations, Lessons LearnedPRO Fact Sheet No. 601 Continued 

# Perform Leak Repair During Pipeline Replacement (Cont’d)

gate valves (130 Mcf per year) and gate valve stem packing (120 Mcf per year) reported in EPA’s Lessons Learned for Directed Inspection and Maintenance at Gate Stations and Surface Facilities . The Partner reported methane emissions reductions of 1,700 Mcf by repairing 12 leaking couplings and 6 valves.



### Economic Analysis

Basis for Costs and Emissions Savings The methane savings of 2,500 Mcf per year were associated with repairing ten leaking pipeline gate valves per year, including replacing valve stem packing. The economic analysis assumes equipment and labor costs of $300 per valve repair. The incremental operating cost is based on 2 operators spending 4 hours per person (at $25 per hour) to test two gate valves for leakage, and repair one. The time for traveling to the pipeline is assumed part of the pipeline project.

Discussion This practice generally has a favorable payback. The value of gas saved by repairing the valve is incidental to safety issues associated with leaking pipeline valves. In addition, timely repair of va lves can avoid system upsets and unplanned shut-downs. The average methane content of na tural gas varies by natural gas industry sector. The Natural Gas STAR Program assumes the following methane content of natural gas when estimating methane savings for Partner Reported Opportunities.

Production 79 %
Processing 87 %

Transmission and Distribution 94 % 

### Methane Content of Natural Gas

EPA provides the suggested methane emi ssions estimating methods contained in this document as a tool to develop basic methane emissions estimates only. As regulatory reporting demands a higher-level of accuracy, the methane emis

sion estimating methods and terminology contained in this document may not conform to the Greenhouse Gas Reporting Rule, 40 CFR Part 98, Subpart W methods or those in other EPA regulations.



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