CHARLESTON, W.Va. — The 600-mile, $5.1 billion Atlantic Coast Pipeline project just received key pieces of regulatory approval in two different states.

Those mark significant steps forward for the interstate pipeline project, which has been marked by promise and controversy.

In West Virginia, the project gained approval for a stormwater permit that is one of the state Division of Environmental Protection’s main enforcement tools on the project. That is the last remaining regulatory approval necessary in West Virginia.

“This is a very significant milestone for the project and one of only a few remaining approvals needed to begin construction,” stated Dominion Energy spokesperson Aaron Ruby.

“This brings West Virginia one step closer to the thousands of jobs and hundreds of millions of dollars in economic activity the project will bring to communities across the state.”

Separately, North Carolina’s Department of Environmental Quality announced it had approved a water-quality certification for the project. More regulatory permits remain necessary in that state.

West Virginia’s DEP announced approval of the stormwater permit on Friday. The agency notified Dominion Energy Transmission, the main developer of the pipeline, through a letter.

MORE: Read the letter from DEP to Atlantic Coast Pipeline developers.

The agency says the permit gives it wide-ranging inspection and enforcement authority, allowing DEP and its enforcement officers to oversee construction activity along the full route of the pipeline including water crossings, uplands, and every other part of the affected surface through which the pipeline crosses.

The letter from DEP reminds the Atlantic Coast Pipeline developers that erosion control measures need to be properly maintained. Disturbed areas need to be covered by appropriate permanent protection, DEP wrote.

Angie Rosser

Many citizens who live along the path of the pipeline still have concerns, said Angie Rosser, executive director of the West Virginia Rivers Coalition.

“We know there is a great deal of anxiety from people living along the proposed route that DEP won’t be able to protect water supplies,” Rosser said as an initial response to the permit approval.

“A pipeline of this size has never been constructed over such mountainous terrain. We’ve seen numerous water quality violations in West Virginia on much smaller scale pipeline projects. I’m afraid we’ll find DEP has put forth an impossible assurance that the plans in this permit will really result in no damage to our streams.”

Last month, DEP touted its belief in the strength of the stormwater permit, which was developed for natural gas projects.

That’s when DEP waived its option to tailor the state’s own requirements within a federal permit specific to the Atlantic Coast Pipeline.

DEP said the state stormwater permit would work in tandem with newly-updated, state-focused requirements in a nationwide U.S. Army Corps of Engineers permit that is reissued every five years.

The agency made the same decision earlier with the similar but separate Mountain Valley Pipeline and drew scrutiny from environmental groups who said waiving state-focused authority is unusual and an abdication of the state’s particular oversight role.

The $5.1 billion Atlantic Coast Pipeline would span 600 miles from Harrison County and across Lewis, Upshur, Randolph and Pocahontas counties in West Virginia through Virginia and into North Carolina. It’s a project by Dominion Energy, Duke Energy, Piedmont Natural Gas and Southern Company Gas.

The Allegheny-Blue Ridge Alliance, a coalition of more than 50 organizations in Virginia and West Virginia, recently announced a citizen initiative to monitor construction activities of the Atlantic Coast Pipeline.

The initiative aims to ensure strict application of environmental laws and regulations, the coalition announced Monday.

“We strongly believe that the ACP is unneeded and cannot be built safely without causing permanent damage to the environment, particularly critical water resources,” stated Rick Webb of the Dominion Pipeline Monitoring Coalition.

“We will continue to challenge the government decisions involving the project. But, with certain pre-construction activities already underway, citizen oversight is essential given the limited resources of government agencies that are responsible for regulating pipeline construction.”

Last week, the Federal Energy Regulatory Commission granted permission to start limited, pre-construction tree felling.

Dominion announced that tree felling and vegetation clearing would begin in short order in West Virginia and Virginia.

“With federal authorization, upland tree felling and vegetation clearing has been underway in West Virginia for several days and will continue through the end of March,” Dominion stated.

Dominion says the work would only be done on properties where agreements have been reached with landowners. The company says none of the work will be done in wetlands, near waterbodies or in other areas that require additional federal and state permits.

The company says full construction is on track to begin in the spring, with completion of the project in late 2019.

“Once we receive a few remaining approvals from other state and federal agencies, we’ll take the final step of requesting a Notice to Proceed with full construction from FERC,” Dominion stated. “We expect to receive these remaining approvals in time to begin full construction activity by the early spring.”