DENVER- At the Rocky Mountain Arsenal Wildlife Refuge, site managers routinely spray pesticides with unknown effects on the site where a $2.1 billion chemical cleanup took place.
“We spent billions of dollars to cleanup a chemical and now we are spraying another,” said David Lucas, manager of the Rocky Mountain Arsenal Wildlife Refuge.
The refuge exists as Denver’s backyard so citydwellers can escape from the crowds to an undeveloped stretch of 16,000 acres of land.
Home to 230 different wildlife species, the refuge is a Western paradise in the midst of metro Denver. On a recent day, bison roamed across the grasslands and prairie dogs popped in and out of holes. In the distance, a natural gas plant released some sort of smoky discharge. The distant high rise buildings of downtown Denver jutted upward into the misty blue sky. Rumbling airplanes took off from Denver International Airport periodically.
During World War II and again during the Cold War, the Department of Defense paid private companies to produce pesticides and biochemicals used for warfare at this site. The land has now been converted into the wildlife refuge. Companies followed the pollution regulations in place at the time but chemicals leaked from unlined basins into groundwater.
Chemicals produced include sarin, DDT, mustard gas, and chloride gas.
The refuge was placed on the National Priority List for clean up in 1967. Clean up efforts included groundwater containment and capping piles of buried toxic waste with grass. Restoration of grass cost $80 million.
“Part of being an urban wildlife refuge is being safe and welcoming,” Lucas said.
So why are officials at the refuge spraying new, potentially harmful pesticides onto the land?
Integrated Pest Management is the method refuge managers use to control unwanted wildlife presence. It simply means using different methods to manage different pests.
Currently, Esplanade, a new pesticide, is being sprayed onto grasslands as part of a multi-year experiment. Site managers are testing it’s effectiveness of diminishing the presence of cheatgrass, an invasive grass species.
Recommendations for Esplanade include spraying it onto post-burn grass while wearing gloves, with all skin covered, according to the Environmental Protection Agency (EPA).
Land management burns one fifth of the wildlife refuge each year to mimic natural burn cycles. The bison prefer eating post-burn grass, Lucas said. Effects on bison from eating Esplanade-treated post-burn grass are unknown so far, he said.
“If we had that research, we would stop,” Lucas said.
Across the state, in the windswept and sparsely populated San Luis Valley, lives Duke Phillips, a fourth generation bison rancher. Phillips aims to avoid using pesticides on his land and administer as few vaccinations as possible to his bison.
“I raise animals in their natural environment,” Phillips said. “That’s my philosophy.”
Raising animals with no chemicals helps preserve the land in its natural state and strengthens the herd, Phillips said.
But Lucas, on his refuge in the middle of a booming metropolis, takes a different stance. He sees chemicals as a smart move economically and as potentially useful in helping his damaged land heal.
“Industry is part of the network we work with….” he said. “If you put your head in the sand and pretend that the realities don’t exist, you’re not doing your job.”
