At its peak , the Laurel Hill Chemical Works , owned by Phelps Dodge , employed approximately 1,250 people .
The workforce declined when the company closed the smelter , and eventually the site was sold to the United States Postal Service in 1986 .
At its peak , the Laurel Hill Chemical Works , owned by Phelps Dodge , employed approximately 1,250 people , but the workforce declined when the company closed the smelter , and eventually the site was sold to the United States Postal Service in 1986 .