Northwest Alloys, Addy

Facility information

This magnesium smelter operated between 1976–2001. The smelter is temporarily shut down and Northwest Alloys, a subsidiary of Alcoa, plans to sell the facility as an industrial site.

• The company has completed mine closure and reclamation requirements at the site.
• Northwest Alloys neutralizes high pH wastewater and mixes it with stormwater, treated sanitary wastewater, and well water. They store this mixture on-site. When there is more wastewater than they can store, they use a limited amount to irrigate croplands.
• Pond 3 stores the old wastewater from the magnesium making process. Northwest Alloys is looking into options for treatment or reuse of this water.

Permit information

• Wastewater permit
  • Support document

Northwest Alloys' location

1560A Marble Valley Basin Road, Addy