Toxic Past to Thriving Wildlife Refuge Near Denver

The Rocky Mountain Arsenal National Wildlife Refuge, located just northeast of Denver, Colorado, is now a vibrant urban wildlife sanctuary. This 15,000-acre refuge supports over 330 species of mammals, birds, reptiles, amphibians, and fish, including bison and bald eagles.

Historically, the land served a different purpose. During World War II, the U.S. Army established the site for producing chemical weapons and rocket fuel. From the 1950s to the 1980s, Shell also leased facilities for pesticide manufacturing, leading to severe land and groundwater contamination from hundreds of chemicals.

Decades of industrial activity resulted in millions of pounds of toxic waste and significant spills. The site was added to the Superfund National Priorities List in 1987 due to widespread pollution affecting wildlife and groundwater, with some disposal methods suspected of triggering earthquakes.

A significant turning point occurred in the 1980s with the discovery of a bald eagle roost, highlighting the site's potential for wildlife. In 1992, Congress designated it a national wildlife refuge.

The extensive cleanup, costing approximately $2.1 billion and spanning 15 years, involved removing contaminated soil, managing waste, and treating polluted groundwater. Around 1,000 acres remain under Army management for waste and treatment facilities.

Today, the refuge is a testament to successful environmental restoration. It has become one of the largest urban wildlife refuges in the U.S., attracting nearly 500,000 visitors yearly. The successful reintroduction of the endangered black-footed ferret further underscores its importance as a critical wildlife habitat.