In his work Uncommon Ground: Toward Reinventing Nature, William Cronon presents the case of the old chemical weapons manufacturing center, the Rocky Mountain Arsenal in Denver, Colorado. This compound was used for 40 years to produce a long list of toxic substances: aldrin, dieldrin (and all the bad guys with an “in” or “ine” termination), mustard gas, napalm, and others, that ended up deposited in the landfills and waste basins of the site. As a result, the whole area of the Rocky Mountain was deserted by human beings and for years avoided by any human visitor.

After its closure in 1992, a new wave of visits started in order to begin an ecological project to clean the area of the toxic substances. It was then discovered as the nation’s “most ironic” wildlife national park. Despite the toxicity of the area, the wildlife populations resulted extremely diverse and abundant: more 300 wildlife species were established in the Rocky Mountain Arsenal. The most polluted landscape of Colorado became the richest wildlife reserve.

Cronon discloses a dilemma: “to clean up its waste dumps even if doing so might endanger the creatures that now make their homes there?”

These species arrived to the Rocky Mountain by a different mix of factors but the lack of human presence was an important one. Cronon states: “there is nothing natural, surely, about the arsenal’s toxicity, and yet, that toxicity is itself one of the most important things supporting the wild nature for which the place is now celebrated”.

“The ability to blur the boundaries between “natural and Unnatural” is precisely what makes the Rocky Mountain Arsenal and other found objects so useful for encouraging us to question our assumptions about what nature means and how we should relate to it”.