The North Carolina Department of Environmental Quality’s Division of Air Quality (DAQ) has issued an air quality permit to Moriah Energy Center, adding stronger reporting requirements to the final permit in response to public comments.
Public Service Company of North Carolina, Inc. (PSNC) plans to liquefy natural gas at Moriah Energy Center, in Person County, during periods of excess capacity and convert it back to natural gas during high demand periods. The facility is planned to be constructed in two phases.
At the end of September, Dominion Energy sold PSNC and its assets to Enbridge, Inc. PSNC remains the owner and operator of Moriah Energy Center for permitting purposes.
The liquefaction system will separate heavy hydrocarbons from the natural gas stream before storage. The heavy hydrocarbon stream will either be routed back to the natural gas pipeline or flared. The majority of emissions at the facility will come from combustion sources including heaters, generators and flares. The facility will also allow tanker truck loading and unloading of liquid natural gas, although the company says this would not be the primary method of transporting the natural gas.
Operation of the facility will be required to emit air pollution at levels below major source thresholds. Air dispersion modeling reviewed by DAQ demonstrated that the facility’s emissions of toxic air pollutants are expected to comply with applicable standards and will not cause an exceedance of any acceptable ambient level.
The final permit includes conditions that ensure ambient levels of all pollutants beyond the facility’s fence line comply with emission standards, including applicable health-based standards. The facility would also be subject to recordkeeping requirements and regular inspections.
DAQ held a public hearing and a public comment period to solicit feedback on a draft of the air permit. Division staff thoroughly reviewed every comment received. In response to these public comments, the final permit increases the frequency at which Moriah Energy Center will be required to report its emissions and operational data to comply with Synthetic Minor limitations, from annual to quarterly. These reports will help DAQ ensure the facility is operating at minor-source levels.
Other responses to public comments included:
- While not required, DAQ requested the U.S. Environmental Protection Agency conduct a full review of the draft air quality permit and review. EPA recommended several edits for clarity that were incorporated, while agreeing that the permit is enforceable and adheres to federal air quality rules.
- DAQ asked Dominion Energy to submit air dispersion modeling for the facility’s emissions of nitrogen oxides. DAQ reviewed this modeling, which demonstrated the facility would not cause an exceedance of federal standards.
- DAQ clarified safety requirements and provided contact information in the hearing officer’s report for the North Carolina Utilities Commission Pipeline Safety Section, which is the agency in North Carolina responsible for ensuring liquified natural gas facilities comply with federal safety standards.
- DAQ requested information from Dominion Energy regarding the sale of PSNC to Enbridge. Based on that information, an ownership change application is not required at this time.
- DAQ made minor corrections for typos and other clarifications in the final documents.
Copies of the final permit, final permit review, hearing officer’s report, permit application, a one-page project fact sheet, and answers to frequently asked questions are available online.