Hover over the interactive map below to learn more about the individual Operable Units and Remedial Design Units of the Anaconda Smelter NPL site or click on the links in the list below.

The Operable Units (OU) and associated Remedial Design Unites (RDU) within the Anaconda Smelter NPL site include:

• Mill Creek Operable Unit
• Flue Dust Operable Unit
• Old Works/East Anaconda Development Area Operable Unit
  1. Golf Course
  2. Industrial Area
  3. Red Sands
  4. East Anaconda Yards
  5. Drag Strip
  6. Mill Creek Addition
  7. Aspen Hills
• Community Soils Operable Unit
• Anaconda Regional Waste, Water and Soils Operable Unit
  1. Stucky Ridge
  2. Lost Creek
  3. Smelter Hill Uplands
  4. Anaconda Ponds
  5. Active Railroads/Blue Lagoon
  6. South Opportunity
  7. North Opportunity
  8. Opportunity Ponds
  9. Fluvial Tailings
  10. Warm Springs Creek
  11. Cashman Concentrate
  12. Slag
  13. Old Works Groundwater
  14. Smelter Hill Facility
  15. Mt. Haggin Uplands

History of the Anaconda Smelter NPL Site

To reduce the costs of smelting the copper ore being mined from his Anaconda Mine in Butte, Marcus Daly began scouting for an area to construct a copper smelting facility. The Irish immigrant found the ideal candidate 26 miles west of Butte in Deer Lodge Valley, and, in 1883, purchased the property. Just one year later, the Upper Works began production with a capacity to treat 500 tons of ore daily. Within five years, the Lower Works were constructed one mile east of the Upper Works, raising the daily capacity of treated ores to 3,000 tons. As Daly’s Anaconda Copper Mining (ACM) Company continued to grow, so too did the town of Anaconda. By the early 20th century, the Anaconda-Butte area was the largest copper producer in the world.

Marcus Daly did not live to see the construction of his third smelter, the Washoe Smelter, which had the capacity to process all of the ore being excavated from the Butte mines. As a result, both the Upper and Lower Works were closed and eventually dismantled. Remnants of these operations such as flumes and brick structures can still be seen along the northern ridge of the valley. In 1977, the Anaconda Copper Mining Company was purchased by Atlantic Richfield Company, which would later be acquired by British Petroleum (BP) in 2000. Three years later, in 1980, Atlantic Richfield Company ceased all smelting operations. Demolition of the facilities began in 1982 and continued until 1986. However, the Washoe Smelter was preserved as a testament of Anaconda’s role in the nation’s mining era. It still stands to this day.

The Anaconda Smelter Site was placed on the Environmental Protection Agency’s (EPA) National Priorities List (NPL) on September 8, 1983. The Anaconda Smelter NPL site encompasses an area of approximately 300 square miles. Due its vastness of size and diversified areas of remedial concern, the site was divided into five of Operable Units, a term used to categorize the numerous activities undertaken as part of a Superfund site cleanup. Additionally, two of these Operable Units were further divided into subareas known as Remedial Design Units (RDU) due to the diverse range of remedial concerns to be addressed within the Anaconda Smelter NPL site.