Dominion Energy Virginia is asking Virginia regulators to approve cost recovery on more than $300 million of environmental upgrades at three coal-fired power plants.
The Dominion Energy Inc. subsidiary on Dec. 14 filed its application for a rate adjustment with the Virginia State Corporation Commission tied to projects underway at its Chesterfield, Clover and Mount Storm coal plants. Dominion is asking to recover $113.7 million from customers from Nov. 1, 2019, through Oct. 31, 2020, for ongoing improvements with a total capital cost of about $302.4 million.
Dominion Energy Virginia, known legally as Virginia Electric and Power Co., said the improvements are necessary to comply with the U.S. Environmental Protection Agency's Coal Combustion Residuals rule and certain Clean Water Act requirements as implemented in Virginia and West Virginia.
To comply with environmental regulations, Dominion said it "changed the way it manages coal ash" at the 1,301-MW Chesterfield Power Station in Chesterfield County, Va., by "switching from a wet process to a dry process so that ash now being produced from coal combustion no longer needs to be stored in ponds." The company said a new, lined landfill at the site should be able to hold the coal ash for up to 20 years. Dominion said it also built a 1,400-foot bridge for truck traffic on site and installed a low-volume wastewater treatment system.
Dominion told state regulators that it is making similar improvements at the 881-MW Clover coal plant in Halifax County, Va. "The ponds are being brought into compliance by retrofitting them with a new liner system that includes compacted clay, a geosynthetic high density polyethylene liner, a geotextile cushion, and a concrete pad," Dominion wrote in its application. "The company also will replace the ponds' pumping system in order to support the new liners. Groundwater monitoring wells will be maintained on-site as long as these ponds are active."
At the 1,676-MW Mount Storm coal plant in West Virginia, Dominion is retrofitting ash ponds with a new liner system made of clay, synthetic and concrete material. "These low-volume ponds must remain operational in order for the station to meet the limits set by its water discharge permit issued by the state of West Virginia," the company wrote. Dominion said it also will install a groundwater monitoring network on site.
The costs for the Chesterfield improvements are estimated at $246.8 million, with $7.6 million earmarked for the Clover Power Station projects and $48 million tied to Mount Storm. If the State Corporation Commission approves the proposed recovery of these costs, Dominion said the monthly bill for the typical residential customer who uses 1,000 kWh of electricity would increase by $2.15 beginning Nov. 1, 2019.
Dominion said it applied a 9.2% return on equity to the proposed revenue requirement. (SCC docket PUR-2018-00195)