US Magnesium Canal Continuation Project Section 401 Water Quality Certification Decision

Project Background

According to the project proponent, the proposed project would extend two intake canals in the Gilbert Bay of the Great Salt Lake to reach open water. The project proponent indicated the extension would maintain connectivity with the necessary source water for its evaporation facility. The proposed project would utilize hydraulic dredging to extend the canals. The existing P-0 Canal is 2.6 miles long and would be extended an additional 3.0 miles, with a 40-foot bottom width and maximum top width of 62 feet. The existing P-North Canal is 1.1 miles long and would be extended an additional 0.7 miles, with a 40-foot bottom width and maximum top width of 55 feet. Both canals would maintain conveyance of lake water intake flows of 100,000 gallons per minute from the Great Salt Lake to the intake pump stations. The proposed project would extend the canals to a bottom elevation of 4,185 feet and the construction corridor would be limited to 300-ft wide.

The proposed project would be an initial phase in establishing long-term access to water from the Great Salt Lake (Gilbert Bay). The project proponent indicated dredging activity would be conducted adjacent to the existing canals to minimize impacts. According to the project proponent, dredged materials would be placed into the lakebed adjacent to the construction corridor in a manner that mimics existing conditions. The project proponent provided three (3) alternatives to dredging, which included facility modifications, and a floating pipe system, and an upland trench system to convey north arm water to the facility:

  1. Facility modifications have been ongoing to maintain operations with lowered lake levels. The facility has been relying on stockpiled surplus to supplement the declining intake capacity but the project proponent anticipates the surplus will be depleted by next year.
  2. The floating pipe alternative would require additional infrastructure including barges, pumps, and anchoring systems. This alternative would be at a higher cost and would be dependent on resource availability.
  3. The project proponent indicated the upland trench system would not meet the facility’s immediate need to access the brine supply necessary to maintain its operations, but stated they may consider it in the future.

Process

On September 22, 2022, the Division of Water Quality (DWQ) Director provided public notice of a Draft 401 Water Quality Certification (WQC) decision for a thirty (30) day comment period. At the request of the public, the Director extended the public comment period for an additional fifteen (15) days and held a public hearing on October 19, 2022. On October 12, 2022, the Director requested an extension of the reasonable period of time and on October 20, 2022, USACE granted DWQ a fifteen (15) day extension, which extended the Director’s certification date to December 15, 2022. The public notice and comment period ended November 14, 2022.

DWQ received seven hundred eighty-seven (787) comments on the Draft 401 WQC decision. On November 15, 2022, the Director again requested USACE to extend the reasonable period of time to ensure sufficient time to process and consider all comments received. On December 2, 2022, USACE approved the additional fifteen (15) day extension, which extended the reasonable period of time for Director action to December 29, 2022.

After continued review of the 401 WQC request and after consideration of the comments received, DWQ determined additional information is required from the project proponent before the Director can make a certifying decision. On December 15, 2022, the Director once again requested an extension of the reasonable period of time for up to one (1) year, requiring the Director to act by September 1, 2023, to allow sufficient time for the project proponent to gather the information and for DWQ to consider the additional information. On December 21, 2022, USACE denied the Director’s extension request. As such, the reasonable period of time for the Director to make a certifying decision is December 29, 2022.

On December 29, 2022, the Director denied the 401 WQC for the proposed project. Director requires additional information in order to make a certifying decision, but the response and evaluation of the necessary additional information would extend beyond the USACE established reasonable period of time and approved extension periods.

Documents

Public Notice Information

Public Comments

Certifying Decision

Administrative Record