FERC’s Office of Energy Projects has finalized its guidance for horizontal directional drill (HDD) practices for natural gas projects after incorporating “substantive comments” in response to a draft version released last year.

The guidance is intended to help operators develop HDD plans to “increase the efficiency and effectiveness” of the Federal Energy Regulatory Commission’s environmental review process and “reduce the need for supplemental data requests,” the agency said.

Topics covered include the technical components of a project’s HDD plan, including drilling fluid composition and management, monitoring procedures and the proper response in the event of an inadvertent return of drilling fluid to the surface. The guidance also covers information “not specifically required by regulation” but that is “often considered during staff’s environmental review.”

FERC released a draft version of the HDD guidance last year to gather comments from stakeholders. FERC said it received comments from 15 entities, including natural gas pipeline companies, engineering firms, trade organizations, environmental groups and state regulators.

“Staff reviewed and considered each comment and modified several portions of the document in response,” the agency said.

The HDD procedures for FERC-regulated projects came under heightened scrutiny after an estimated 2 million gallon inadvertent return occurred at an HDD crossing of the Tuscarawas River in Ohio during the construction of the Rover Pipeline in 2017.

That incident led to a temporary moratorium on HDD activities for the 3.25 Bcf/d natural gas line and preceded months of back and forth between developer Energy Transfer LP and regulators.