On 9/23/21, after 17 years of comments, litigation, competing projects, environmental analysis and more, a 40-year license was issued to Pine Creek Mine, LLC for the Pine Creek Mine Hydroelectric Project (P-12532-006) by the Federal Energy Regulatory Commission (FERC), but with many requirements and stipulations…. The project creatively converts the closed Union Carbide Tungsten Mine into a source of renewable energy that can produce 1.5 MW of electricity with the water that naturally flows through the mine shafts.  

Snow melt and groundwater currently flow through the mine at an average rate of 10 cfs and comes out a rock trench, down steel and HDPE pipes, to the intake for the 150-kW generator at the Water Discharge System Sites (installed under project P-13163). It then flows into a pond where it spills over into Morgan Creek, a tributary of Pine Creek. The basic concept for this project is to generate electricity from that flow. To better control the flow, a plug in the Easy Go Adit will allow water to form a reservoir in the tunnel. The water would then be released down a pipe to a generator at about the rate of the water naturally coming into the adit. In 2002, a plug was installed, a reservoir of water formed, and then released to see if any of the elements in the rock contaminated the water. The concern was that storing water would pull contaminants out of the rock that would end up in Morgan Creek. Tungsten is not easily dissolved and the test showed elements were within acceptable ranges before and after.

The license was issued with many stipulations required by FERC, the US Forest Service and the California State Water Resources Control Board with deadlines for compliance:

• While streambed alterations are not planned, CDFW must be notified beforehand if it is needed.
• The tunnel plug must be proven to be safe and to withstand 5.0 earthquakes. If the current plug cannot be proven safe, it will be replaced.
• There must be an operation compliance monitoring plan that meets the state Water Board’s requirements, an avian collision/electrocution hazards plan, an initial fill plan, a water quality monitoring impoundment draining/refill management plan, a hazardous substance management plan, a public safety plan, a road management plan, water quality and temperature monitoring, aquatic biological monitoring, and more.
• Clean Water Act certification, which has 32 conditions to be met.
• Construction is limited to July 1-September 30 to not impact the Sierra Nevada Bighorn Sheep that are in the area. It must start within 2 years and end within 5 years of the issuance of the license.
• A water quality protection plan for the construction phase.
• Notification to the State Historic Preservation Officer and USFS if cultural resources are found.
• Minimum Morgan Creek stream flows must be met.

The Pine Creek Tungsten Mine began in 1918 on the south slope of Mt. Morgan north of Bishop, CA. Its heyday was 1940-1990 run by the Union Carbide Corporation. It was the largest producer of tungsten in the U.S., used in steel. The tunnels go 2.5 miles into the mountain and up 2,800 feet. Watch an interesting Union Carbide Corporation documentary on the tungsten mine operations.

Find more information about the permit here. Enter P-12532 in the Enter Docket Number, select “All” in the Past 60 Days field and then hit enter. To narrow the search to the EA, select “Custom” in the Past 60 Days field and enter “08/26/2020” in the From field.