Minntac Tailings
Minntac Tailings is an earth dam located in St. Louis County, Minnesota, built in 1978. It carries a Low hazard potential classification.
About Minntac Tailings
The primary purpose of Minntac Tailings is tailings. Tailings dams contain waste material from mining operations — typically a slurry of finely ground rock left over after valuable minerals have been extracted. These structures require ongoing monitoring because tailings can contain heavy metals and other contaminants. The dam is owned by Us Steel (private). It impounds the Closed System-os near Local Residents.
The dam stands 50 feet tall and stretches 63,360 feet across, has a maximum storage capacity of 143,000 acre-feet, and collects water from a drainage area of 13 square miles. Completed in 1978, the structure is 48 years old.
This dam has a low hazard potential classification, meaning that failure would cause minimal damage, limited primarily to the dam owner's property, with no expected loss of life. The most recent inspection on record was 11/06/2024.
At 50 feet, this dam is taller than 93% of dams nationwide.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | Minnesota |
| County | St. Louis |
| Nearest City | Local Residents |
| River/Stream | Closed System-os |
| Coordinates | 47.59860, -92.62857 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 50 ft |
| Dam Height | 50 ft |
| Dam Length | 63,360 ft |
| Year Completed | 1978 (48 years old) |
Storage & Hydraulics
| NID Storage | 143,000 acre-ft |
| Max Storage | 143,000 acre-ft |
| Normal Storage | 114,000 acre-ft |
| Drainage Area | 13 sq mi |
Ownership & Safety
| Purpose | Tailings |
| Owner | US Steel |
| Owner Type | Private |
| Hazard Classification | Low |
| Last Inspection | 11/06/2024 |
| Emergency Action Plan | Not Required |
Identifiers
| NID ID | MN00672 |
| Federal ID | MN00672 |
| More Info | State Dam Safety Program |