The Interstate Natural Gas Association of America (INGAA) contends that the methane and volatile organic chemical (VOC) emission limits for transmission pipelines proposed by the EPA will in many instances be difficult to comply with.
Don Santa, president and CEO of INGAA, said, “While we haven’t had a chance to review fully the 500-plus page proposal, INGAA is concerned that some aspects of the EPA’s methane proposal would be impossible to implement cost-effectively, and that the regulations, if implemented, could adversely affect the reliability of interstate natural gas pipelines.”
The proposed rule issued in August would add requirements for detecting and repairing leaks, and limiting emissions from compressors, pneumatic controllers and pneumatic pumps used at compressor stations. This would be the first time the EPA would require air emission limits from transmission pipeline compression stations.
The requirements would apply to “new or modified” equipment, so the existing compression at pipeline stations would not be affected unless a transmission company proposes a FERC 7C project for a 0capacity change. Then that facility would be considered “modified,” says Cathy Landry, spokeswoman for INGAA. Those applications are “not common,” she states.
However, significant numbers of new compression stations are in the industry’s future. An INGAA Foundation report from March 2014 estimated the U.S. and Canada will require each year through 2035 an average of 850 miles of new natural gas transmission mainlines, 800 miles of new laterals to and from power plants, processing facilities and storage fields and almost 14,000 miles of new gas gathering lines to bring gas supplies to growing markets.
For those new and modified compression station pieces of equipment which are affected, the EPA contends the costs of compliance will be far outweighed by the benefits of recovered fugitive emissions of gas. The EPA has collected data from Natural Gas STAR partners, where transmission companies voluntarily interact with the EPA to reduce air emissions, which shows that instituting a DI&M program at a compressor station costs $26,248 per station and returns $88,239 per year in recovered gas. DI&M stands for Directed Inspection and Maintenance, which is a voluntary approach to reducing emissions.
It isn’t clear when the Natural Gas STAR program made that cost/benefit analysis. Jerome Blackman, who heads that EPA program, did not reply to an email seeking clarification.
Some pipeline companies have participated with the Natural Gas STAR program. Kinder Morgan has participated in the EPA program since 1993, and some of its acquisitions, such as El Paso Natural Gas, have also been longtime participants. Asked about the impact of the proposed rule on his company, Richard Wheatley, spokesman for Kinder Morgan, Inc., says, “We’re monitoring and working through INGAA.”
The proposed rule requires a 95% reduction in VOC emissions from compressors with wet seal systems. This can be accomplished through flaring, or by routing captured gas back to the compressor intake. Compressors using dry seal systems, which have low methane and VOC emissions, would not be covered by the proposed rule.
The proposed rule provides two options for replacing rod packing in reciprocating compressors: every 26,000 hours of operation (operating hours must be monitored and documented); or every 36 months (monitoring and documentation of operating hours not required). As an alternative to changing rod packing, operators may opt to route emissions from the rod packing via a closed vent system to be reused or recycled by a process or piece of equipment.
The proposal affects continuous bleed, gas-driven pneumatic controllers which are located between the wellhead and the point where gas enters the transmission pipeline. For controllers used at natural gas compressor stations, the gas bleed limit is 6 standard cubic feet per hour (scf/hr) at an individual controller. Low-bleed controllers used at stations (with a gas bleed rate less than 6 scf/hr) would not be subject to this rule.
EPA proposes owners/operators of compressor stations use a technology known as optical gas imaging to conduct a leaks monitoring survey. Owners/operators would conduct the survey within 30 days after modification or startup of a new compressor station and then repeat the survey twice yearly. The survey would cover several components, including valves, connectors, pressure-relief devices, open-ended lines, access doors, flanges, crank case vents, pump seals or diaphragms, closed-vent systems, compressors, separators, dehydrators, and thief hatches on storage tanks, among others.
Any leaks found during the surveys would have to be repaired within 15 days, unless the repair would require shutting down production. In that case, owners/operators would be required to fix the leak at the next scheduled shutdown. The proposed rule includes incentives for minimizing leaks. If leaks are found from less than 1% of covered components during two consecutive surveys, owners/operators may conduct the monitoring survey yearly instead of every six months.
If leaks are found from 1-3% of covered components, operators would have to continue monitoring every six months. Operators of sites with leaks from over 3% of covered components during two consecutive monitoring surveys would have to monitor every three months.
FAA Considers Restrictions on Drones for Pipeline Surveillance
The Federal Aviation Administration (FAA) is moving to restrict the use of pilotless drones, which are used by the pipeline industry for inspection of facilities in remote, mountainous areas. INGAA has taken issue with a proposed requirement limiting operation of unmanned aircraft systems (UAS) to situations where the operator maintains line-of-sight contact with the drone.
The FAA Modernization and Reform Act of 2012 directs the Secretary of Transportation to determine whether “certain unmanned aircraft systems may operate safely in the national airspace system.” The FAA proposed rule sets out certain standards for UAS which will be allowed to operate. This would limit small UAS to daylight-only operations, confined areas of operation, and visual-line-of-sight (VLOS) operations. Operators would have to be certified.
It is the line-of-sight visual contact requirement INGAA objects most strongly to. “INGAA submits that this requirement is overly restrictive and inadvertently precludes pipeline operators from using UAS for operation, maintenance and construction monitoring activities,” states Terry Boss, senior vice president for environment, operations and safety.
INGAA wants the FAA to eliminate the line-of-sight requirement for pipeline operators as long as the UAS activities are conducted (1) within the pipeline corridor, (2) pursuant to the landowner easement agreement, and (3) using a UAS equipped with a forward-looking camera and utilized geofencing, location and altitude sensing technology.
Sens. Cory Booker (D-NJ) and John Hoeven (R-ND) have introduced a bill titled the “Commercial UAS Modernization Act (S. 1314) which would expand the use of exemptions to allow UAS flights outside the operator’s line of sight.