Mansfield Canyon mine remediation work continues

TUCSON, AZ, July 11, 2019 – The Mansfield Canyon Removal Action is an ongoing environmental remediation project of three abandoned mine sites, the former Dixie Mine, Hosey Mine and Site 7, which are located within Mansfield Canyon Watershed on the Nogales Ranger District of the Coronado National Forest.


The purpose of this remediation is to prevent the migration of waste materials containing heavy metals such as lead and arsenic from migrating off site and into the surrounding environment. Currently, the project is 80% complete. At Dixie approximately 5,000 cubic yards of waste material were excavated, deposited in an onsite cell and encapsulated with three feet of clean soil. The Dixie Consolidation Cell has been completed and disturbed areas of the site were contoured to match existing terrain and seeded with a native seed mix collected by Borderlands Restoration, a local non-profit organization.


Waste material from Hosey and Site 7 was excavated, hauled and placed in the Main Repository. Excavation and construction of the Main Repository was completed the last week of February. Approximately 42,000 cubic yards of waste material were excavated, hauled and deposited in the repository and were covered with eighteen inches of clean soil in preparation for the installation of an HDPE liner. The liner will then be covered by six feet of additional clean material. Following the completion of the Main Repository the mine sites will be re-seeded with native plants, shrubs, and trees, collected by Borderlands Restoration.

Heavy construction equipment is required for completion of the environmental remediation. Access to Mansfield Canyon will continue to be closed to the public until August 31st. A Special Closure Order has been issued by the Coronado National Forest Supervisor for sections of Forest Roads 72, 72A, 762, 4091, 4092, and 4094. (Descriptions can be found at .) The Arizona Trail has been temporarily re-routed. It is imperative that the public remain clear of the area for the duration the closure is in effect. Heavy machinery poses a safety threat to hikers, off highway vehicle users, hunters, and all other recreationalists. Violation of the closure could result in fines of not more than $5,000 for individuals and $10,000 for organizations, six-months imprisonment, or both.