EPA Sued Over Pollution Damage to Endangered Butterfly

Lange's metalmark butterfly | Photo: USFWS/Flickr/Creative Commons License

The U.S. Environmental Protection Agency violated the Clean Air Act when it approved a permit for a large gas-fired power plant that may drive an endangered butterfly to extinction. That's according to a San Francisco-based environmental group that filed suit against the EPA last week.

According to the Wild Equity Institute's lawsuit, filed last Wednesday in the U.S. District Court in Northern California, the EPA broke the law when it failed to demand pollution control measures at Pacific Gas and Electric's Gateway Generating Station in Antioch, which is adjacent to the Antioch Dunes National Wildlife Refuge.

Emissions from the plant, which went online in 2008, are considered a serious threat to the the federally endangered Lange's metalmark butterfly, whose numbers are down to just a few dozen adults found only at the dunes. The U.S. Fish and Wildlife Service says those emissions "are virtually certain" to kill off the last Lange's metalmarks. Wild Equity's lawsuit seeks to force EPA to implement the same pollution control measures followed by other power plants in this industrialized section of Contra Costa County.

Wild Equity Institute, along with the Center for Biological Diversity and Communities for a Better Environment, filed a notice of intent to sue EPA on a closely related issue stemming from the pollution last July. That lawsuit has not yet been filed.

The Antioch Dunes are a relict ecosystem of wind-blown sand deposited during the Pleistocene, protected in a small fenced area on the south shore of Suisun Bay. Sand dunes are almost always deficient in nitrogen, a vital plant nutrient, and the Antioch Dunes have developed a unique assortment of plants, some endangered themselves, that are able to cope with nitrogen deficiency.

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One of those plants is the naked-stemmed buckwheat, Eriogonum nudum auriculatum, which is also found elsewhere along the Central California coast and adjacent mountains.

But at the Antioch Dunes, the naked-stemmed buckwheat takes part in an ecological relationship it doesn't have anywhere else: it's the sole larval food plant for the Lange's metalmark, Apodemia mormo langei. The butterflies lay eggs on the buckwheat. Those eggs hatch, caterpillars emerge, and they start to chow down on the buckwheat's leaves and stems, growing all the while. Eventually they pupate, metamorphose into adults, mate and lay eggs on buckwheat.

Without the buckwheat, the endangered metalmarks are doomed, And it's the nitrogen-poor sandy soil at the dunes that allows the buckwheat to thrive. Which is where the Gateway Power Plant comes in. Burning natural gas creates oxides of nitrogen as a waste product: when those compounds settle on the soil at the Antioch Dunes, they fertilize invasive plants that the USFWS expects to crowd out the buckwheat, dooming the Lange's metalmark.

According to Wild Equity Institute, the EPA was legally obligated to require pollution control for the Gateway plant in operating permits the agency issued under Title V of the Clean Air Act. In September 2013, Wild Equity petitioned the EPA to take steps to re-do Gateway's Title V permit. EPA was legally required to respond to that petition within 60 days, but never did respond. As a result, Gateway's Title V permit became effective without the agency addressing Wild Equity's concerns about the power plant's damage to local air quality.

It's not just about the butterfly, of course: pollutants emitted by Gateway will likely have a deleterious effect on the health of people living downwind, in what's already a highly polluted part of Contra Costa County.

"PG&E needs to play by the same rules as everyone else," said Laura Horton, Staff Attorney at Wild Equity Institute. "Other power plants have already taken measures to do right by communities and our imperiled wildlife, and EPA cannot let PG&E off the hook just because the utility is the biggest player on the block."

For ongoing environmental coverage in March 2017 and afterward, please visit our show Earth Focus, or browse Redefine for historic material.
KCET's award-winning environment news project Redefine ran from July 2012 through February 2017.

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