Conservation groups announced Wednesday that they are suing the U.S. Environmental Protection Agency for failing to protect an endangered butterfly species from a San Francisco Bay Area gas-fired power plant. The groups say the EPA's approval of Pacific Gas & Electric's Gateway Generating Station in Antioch puts the critically endangered Lange's metalmark butterfly in immediate peril of extinction, as well as increasing the risk to public health in a largely working class part of the Bay Area.
The suit was filed by the Center for Biological Diversity, Communities for a Better Environment, and Wild Equity.
At issue are nitrogen emissions from the the Gateway Generating Station. Those emissions blow downwind and settle on the soil at the Antioch Dunes National Wildlife Refuge, home to the Lange's metalmark, the Contra Costa wallflower, and the Antioch Dunes evening primrose, all three of which basically exist nowhere else.
The dunes also host populations of the native naked stem buckwheat, which serves as the food plant for Lange's metalmark caterpillars.
The dunes were formed by sand washed down off the growing Sierra Nevada range to floodplains along the Bay and coast, then blown back inland by the prevailing winds. Once part of an extensive dune system that ran throughout the edges of the Sacramento Delta region, the Antioch Dunes were mined extensively throughout the 19th and early 20th centuries. Only 55 acres of dunes remain, most of them heavily altered by encroaching non-dune vegetation.
Nitrogen pollution speeds the process of vegetative encroachment. Nitrogen is an essential plant nutrient usually deficient in sandy soils. Adding nitrogen to the soil allows plants to grow in sand that wouldn't otherwise survive there, potentially displacing the dune buckwheat the butterflies rely on. That could send the butterfly over extinction's brink. There are as few remaining as a few dozen.
In addition to the threat to wildlife, the plant's pollution has its impact on the surrounding human community. Northern Contra Costa County has long been the site of a disproportionate amount of fossil fuel pollution, from refineries in the west to the five gas-fired plants in Antioch and Oakley that send power to cleaner, more affluent communities.
"These communities are harmed by a large number of power plants, each of which emits greenhouse gases and pollutants that are toxic both to the people who live, work and go to school near the plants, and the surrounding environment," said Roger Lin, an attorney at Communities for a Better Environment.
"Four other power plants in the Bay Area have adopted model agreements to protect endangered butterflies from nitrogen pollution and also protect local communities," said Laura Horton, staff attorney at the Wild Equity Institute. "PG&E has already been put on notice twice of their violations. This is PG&E's last chance to do the right thing or its three strikes and they're out."