Virginia Gov. Ralph Northam signed bipartisan legislation March 20 that requires Dominion Energy Virginia to excavate and recycle coal ash from unlined impoundments at four power plants.

Under Senate Bill 1355 and House Bill 2786, the Dominion Energy Inc. subsidiary must excavate about 27 million cubic yards of coal ash adjacent to rivers at its Possum Point, Bremo Bluff, Chesterfield and Chesapeake power stations. At least 25% of the ash would be recycled for beneficial use, and the remainder would be stored in lined landfills. The agreement also would limit removal costs that can be recovered from ratepayers to $225 million in any given year.

Dominion Energy Virginia, known legally as Virginia Electric and Power Co., must complete the closure of each coal ash impoundment within 15 years after the process begins.

The legislative compromise lifts the state's moratorium on the permitting process for coal ash pond closures in the Chesapeake Bay watershed.

"The potential risks to public health and water quality posed by unlined coal ash ponds in the Commonwealth are far too great for us to continue with business as usual," Northam said in a news release. "This historic, bipartisan effort sets a standard for what we can achieve when we work together, across party lines, in the best interest of all Virginians. I am proud to sign this legislation into law."

Dominion Energy has voiced its support for the measure.

"We believe the legislation provides a fair balance between Dominion Energy's customers and its shareholders and allocates the costs of this program equitably among large and small users of electricity," Chairman, President and CEO Thomas Farrell II said on a Feb. 1 earnings call.

The moratorium on permitting for coal ash pond closures was enacted in April 2017 in response to "tremendous public concern" about the process. During the permit ban, Dominion Energy Virginia was required to evaluate "clean closure" and beneficial reuse options for coal ash impoundments in the Chesapeake Bay watershed.