Pipeline compressor station raises questions
Concerns include methane leaks, safety regarding barn-sized, unmanned operation
The natural gas pipeline project that’s planned to pass through nine Franklin County towns includes an element that few may be aware of: a barn-sized compressor station to maintain pressure on the line.
The pumping station, which a Tennessee Gas Pipeline Co. map of its proposed Northeast Energy Direct project shows to be located on a site near the Conway-Ashfield town line, is one of several such facilities placed every 50 to 60 miles to maintain and advance the flow of 2.2 billion cubic feet of natural gas per day, according to an analysis by the Ashfield-based anti-pipeline group Hilltown Community Rights.
The 296-mile pipeline project — which would cross nine Franklin County towns on its way from New York State to Dracut, north of Lowell — has not yet been formally proposed to the Federal Energy Regulatory Commission, but a “pre-application” for expedited environmental review is scheduled to be submitted in September, according to Richard Wheatley, a spokesman for TGP’s parent company, Kinder Morgan. That review of “environmental and other issues,” he said, should speed up the process for FERC’s Certificate of Public Convenience and Necessity to be determined. The formal application for that certificate is not scheduled to take place until the fall of 2015 for the project, which is scheduled to begin operation Nov. 1, 2018.
Jim Cutler of Hilltown Community Rights said group members have determined the compressor station’s location as between Pfersick Road and Shirkshire Road or east of Shelburne Falls Road, based on examination of TGP route maps and a review of topographical maps in the area.
Wheatley said that despite his company’s map showing a station in Franklin County west of the Connecticut River, “The exact number and locations of compressor stations has yet to be determined and will be dependent on final market and system capacity.”
The unmanned stations, which operate around the clock, are typically located on sites that Wheately said average about 25 to 30 acres and could have one or more compressor units.
According to the U.S. Energy Information Administration, most of the stations consist of several compressors, scrubbers, filters and cooling facilities, emergency shutdown systems and a computerized flow control and dispatch system that is monitored by an off-site supervisory control system that manages and coordinates several related stations.
After compression, the compressed natural gas goes to a cooling unit, and then is returned to the transmission line.
Most compressor stations are fueled by some of the natural gas flowing through the station, and compressor stations are equipped with emergency shutdown systems that can detect an unanticipated pressure drop, gas leak or other abnormal conditions, according to EIA.
Members of groups opposed to the pipeline have raised concerns about noise from the compressor stations as well as what they claim would be toxic air emissions both from burning the gas in engines that power the compressors and from periodic release of methane and other chemicals in the pipeline gas, which they say can contain traces of the chemicals used in hydraulic fracturing used to extract natural gas shale.
Wheatley said, “The gas can be evacuated safely to the atmosphere under controlled conditions to perform maintenance.”
He added, “Compressor stations do not ‘exhaust’ or ‘release’ methane gas under normal operations. Piping systems are specifically designed and tested to prevent methane gas release, he said.
“Very small” quantities of gas are vented when gas is used as a power source for normal compressor station operations, he said. In other special operating circumstances, gas is vented to depressurize pipes in the compressor station to allow maintenance or under emergency conditions. When gas is vented, it is done under controlled conditions specifically designed to allow depressurization to be done safely.
Cutler said the group plans to have discussions with local emergency management officials, whom he said would be required to respond if there are off-gas releases to release pressure in the line, and also local health board members because of health concerns from emissions.
As currently configured, the proposed pipeline’s route includes Ashfield, Conway, Shelburne, Deerfield, Montague, Erving, Northfield, Warwick and Orange.
You can reach Richie Davis at: firstname.lastname@example.org or 413-772-0261, Ext. 269