The Willapa Grays Harbor Oyster Growers Association has filed an appeal of the state Department of Ecology’s denial of the growers’ proposal to use a controversial pesticide to control burrowing shrimp.

The appeal from the growers asks the Pollution Control Hearings Board to overturn the decision by the Department of Ecology (DOE), and says the decision to deny use of imidacloprid — the name of the pesticide — was for political reasons and based on faulty science.

“Ecology has, for political and ideological reasons, taken more than two years to process a permit application, only to deny it based on faulty science and contrary to its own prior analysis of that science,” the oyster growers’ attorney Douglas Steding wrote in the appeal.

The native burrowing shrimp have had serious negative impacts on local oyster growers for years, as the shrimp can infest the mud beneath oyster farms and turn it into a slurry, causing oysters to sink under the mud and die. Some oyster growers have said the shrimp problem threatens to put them out of business.

In September, DOE issued a finalized denial of the pesticide after tentatively denying it last April. After the tentative denial, DOE said it reviewed and responded to more than 3,000 public comments about the pesticide before finalizing the denial.

According to the growers’ press release, they say DOE was wrong to consider decisions in Canada and the European Union to ban imidacloprid, and claim that the studies Ecology referenced were “overwhelmingly focused on the effects of freshwater insects, not marine invertebrates (such as oysters), and are not applicable.”

The press release goes on to say that DOE’s denial has prompted the Pacific County Commissioners to “declare a state of emergency in the county, condemn the state for turning its back on the region for purely political reasons, and call on the state and federal officials to provide relief.”

An original permit for imidacloprid was approved in 2015, but the growers requested the permit be cancelled after a public backlash regarding the pesticide. According to the press release, the second application for imidacloprid in 2016 would have reduced the acres they could treat from 2,000 to 500.

Shellfish growers estimate that, if left uncontrolled, the burrowing ghost shrimp infestation could cause oyster production to collapse by up to 90 percent in the coming years, the press release says. More information about the burrowing ghost shrimp infestation and the growers association’s proposed pest-control program can be found at https://protectwillapabay.org/.