Page 13 - ETRN 2019 Interim CSR Report test
P. 13

Voluntary Reduction Programs                        Utilizing Air Starts on Units
              Various industry organizations offer voluntary      Rather than utilizing natural gas, newer
              reduction programs that provide an organized        compressor stations are equipped with
              set of metrics and an accountability structure,     air or electric systems to start engines.
              allowing companies to reduce methane
              emissions beyond regulatory requirements            Replacement of High-Bleed Controllers
              and to quantify such reductions.
                                                                  A high-bleed controller has a continuous
                                                                  natural gas bleed rate greater than six
              During the second quarter of 2019, we joined
                                                                  standard cubic feet per hour (scfh). ETRN has
              the Environmental Partnership (EP) – a
                                                                  replaced numerous high-bleed controllers
              voluntary reduction program offered through
                                                                  with models that have lower bleed rates.
              the American Petroleum Institute (API) and
              the ONE Future Coalition, which is a group of
                                                                  Reducing Full Emergency Shut Down
              natural gas companies working together to
                                                                  (ESD) System Test Emissions
              voluntarily reduce methane emissions across
                                                                  Compressor stations regulated by the DOT
              the natural gas supply chain, with a goal to
                                                                  are required to undergo an annual test of
              lower emissions to 1% by 2025.
                                                                  the ESD system. Previously, ETRN conducted
                                                                  annual ESD tests in a manner that vented
              Current Methane Mitigation Methods
                                                                  all gas contained in the station. We have
              Below is a list of several GHG mitigation
                                                                  updated our operating procedures to only
              projects being implemented across different
                                                                  blowdown the full station once every five
              parts of our operations:
                                                                  years, as allowed by DOT regulations. During
                                                                  the four tests that occur during a full-station
              Compressor Blowdowns to Suction
                                                                  blowdown, the operations team blocks the
              or Reduce Pressure
                                                                  vents and actuates the ESD valves, but does
              During planned blowdowns, discharge gas             not blowdown the piping, thus mitigating
              will be recycled to suction gas prior to venting    any emissions.
              to the atmosphere at compressor stations
              that are equipped to do so. Since suction           Work-Stacking
              pressure is less than discharge pressure, this
                                                                  In 2018, ETRN began an effort to coordinate or
              practice reduces the volume of gas (and
                                                                  “stack” work that required station shutdowns.
              methane) that is vented to the atmosphere.
                                                                  Since work that requires a shutdown often also
                                                                  requires a blowdown, the “work-stacking” effort
              Utilizing Instrument Air
                                                                  minimizes emissions while also maximizing
              Newer compressor stations are equipped              equipment uptime and availability.
              with instrument air systems to run pneumatic
              controllers. Utilizing this type of system          An early opportunity to stack work was
              prevents natural gas from “bleeding” into the       identified for newer Caterpillar units,
              atmosphere, as most pneumatic controllers           which are required to have a rod packing
              have a non-zero bleed rate.                         replacement at 26,000 hours and a major



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