By Gary Dillard
One aspect of Bisbee which I point out to our riders is the proliferation of yellow sandbags around town, with an explanation of the history and process.
Bisbee had a smelter between 1880 and 1903, located where the Queen Mine Tour is today. As well as putting out gases, it emitted particulates. (Later, smelters would be able to install electrolytic precipitators to removed these solids from the gas stream, both because of their value and for health considerations.) Some of these particulates were heavy metals, such as lead, and some of them settled into the local soil.
Smelter emissions weren’t the only cause of lead in the soil. House paint used to contain lead as well, and every time someone scraped the paint off into the yard, the lead remained in the soil. Nevertheless, a few years ago, Freeport McMoRan Copper & Gold Inc. began its local soil program, testing all of the soil in greater Bisbee. Where metals were found to be above a certain threshhold, the company has dug up the soil, disposed of it, replaced it with clean soil and planted it to prevent erosion. Continue reading “What are all the yellow sandbags around Bisbee for?”