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 reduce 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 Learned 
 

 

 

 

PRO 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 valves can avoid system upsets 

and unplanned shut-downs. 

The average methane content of natural 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 emissions 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 emission 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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