The Pennsylvania Department of Environmental Protection (DEP) has approved an air quality plan for the Atlantic Sunrise natural gas pipeline project, signing off on construction activities for the greenfield expansion, which could begin next week.

DEP authorized the plan for air emissions related to construction activities for he 1.7 Bcf/d project to expand the Transcontinental Gas Pipe Line (Transco) system and open a much needed path to carry more shale natural gas from Northeast Pennsylvania.

“DEP thoroughly reviewed the application to ensure that temporary emissions during the construction phase of this project will be minimal and completely offset by reductions elsewhere,” said Secretary Patrick McDonnell.

The approval authorizes using emission reduction credits to comply with the offset requirements of Pennsylvania law.

The 200-mile greenfield portion of the project would cross 10 counties, where Transco parent Williams plans to install about 184 miles of pipe. Partial service began earlier this month on a number of the project’s brownfield portions.

Transco has asked FERC for notice to proceed on the remainder of the project by Sept. 19. The company received approval for the compressor facilities last week, but it is still waiting for notice to proceed with constructing the greenfield pipeline, Williams spokesman Christopher Stockton said.

Transco has executed binding precedent agreements with nine shippers. Cabot Oil & Gas Corp. (1 Bcf/d), Chief Oil & Gas LLC (420 MMcf/d) and Seneca Resources Corp. (190 MMcf/d) have contracted for the highest volumes. The Federal Energy Regulatory Commission certificated the project in February, and the DEP issued the last of the state permits last month.