The Federal Energy Regulatory Commission (FERC) has directed the Klamath River Renewal Corporation (KRRC) to submit a revised blasting plan for removing the lower diversion tunnel intake structure at the Iron Gate Development. In an April 2, 2024 letter, FERC stated that it is unable to authorize the blast based on the information provided in KRRC’s March 26 submittal.
The blast plan, which applies only to the lower intake structure, proposed removing the entire historic tunnel intake, including all valves, machinery and equipment, in a single blast. Any remaining parts would then be mechanically removed. However, FERC has requested that KRRC provide additional details before the plan can be approved, including:
- Plan drawings and cross-sections showing the location, depth, angle and type of each blast hole
- Specific criteria for determining hole depth, which will be determined in the field
- Maximum number of holes per delay
- Designating which holes will be decked vs production holes based on the current understanding of the structure
- Details on the decking hole configuration and stemming height
- Clarification that holes in each row will detonate simultaneously with 75ms delays between rows
- Total number of gelatin cartridges to be used
- Blast mat details
- Discussion of impacts on abutment rock stability
