Northern Natural Gas Company Requests Approval for Temporary Pipeline Evacuation System

Strategic Insights -

Northern Natural Gas Company, a subsidiary of Black Hills Corporation, has submitted a request to the Federal Energy Regulatory Commission (FERC) to utilize a temporary pipeline evacuation system (compression) to accommodate tie-in activities for the Elk River 3rd branch line extension. The proposed system will depressurize the existing Elk River MNB87701 branch line to complete the tie-in of the Elk River extension. Northern Natural Gas estimates that the temporary compression will reduce natural gas vented to the atmosphere by approximately 6.797 MMcf.

The company has hired Stantec Consulting Ltd. to evaluate the noise impact of the proposed temporary compression on noise-sensitive areas (NSAs) within 0.5 mile of the Hugo compressor station in Minnesota. The study found that the mitigated noise impact at the representative NSAs would be less than the applicable FERC 55 dBA Ldn criteria. Northern Natural Gas is proposing to install a 4-meter high 25-meter long L-shaped barrier wall along the northern and eastern sides of the temporary compression activities to reduce noise levels.

Key Takeaways:

  • Northern Natural Gas Company requests approval to utilize a temporary pipeline evacuation system (compression) to accommodate tie-in activities for the Elk River 3rd branch line extension.
  • The proposed system will depressurize the existing Elk River MNB87701 branch line to complete the tie-in of the Elk River extension.
  • Northern Natural Gas estimates that the temporary compression will reduce natural gas vented to the atmosphere by approximately 6.797 MMcf.
  • Stantec Consulting Ltd. evaluated the noise impact of the proposed temporary compression on NSAs within 0.5 mile of the Hugo compressor station in Minnesota.
  • The study found that the mitigated noise impact at the representative NSAs would be less than the applicable FERC 55 dBA Ldn criteria.
  • Northern Natural Gas is proposing to install a 4-meter high 25-meter long L-shaped barrier wall along the northern and eastern sides of the temporary compression activities to reduce noise levels.
  • The contractor is scheduled to mobilize to the site on September 22, 2025, and commence depressurization on September 23, 2025.

Statistics:

  • The proposed pipeline evacuation system will be a 300-horsepower (HP) system.
  • The compressor will be located at the northeast corner of the Hugo compressor station.
  • Approximately 14.8 miles of the MNB87701 branch line will be isolated starting at the Hugo compressor station to a block valve in Section 26, Township 32N Range 23W, Anoka County, Minnesota.
  • The temporary compression activities are expected to reduce natural gas vented to the atmosphere by approximately 6.797 MMcf.
  • The mitigated noise impact at the representative NSAs is expected to be less than the applicable FERC 55 dBA Ldn criteria.

Sources:

  • Northern Natural Gas Company P.O. Box 3330 Omaha NE 68103-0330 402 398-7200 August 29, 2025 Via eFiling Ms. Debbie-Anne Reese, Secretary Federal Energy Regulatory Commission 888 First Street, N.E. Washington, D.C. 20426 RE: Northern Natural Gas Northern Lights 2025 Expansion Docket No. CP24-60-000 Variance Request - Utilize Temporary Pipeline Evacuation System for Tie-in Activities - Elk River 3rd Branch Line
  • Stantec Consulting Ltd. 1165 Scheuring Rd., De Pere, WI August 29, 2025 File: Docket No. CP24-60-000 Attention: Debbie-Anne A. Reese, Secretary Federal Energy Regulatory Commission 888 First Street, N.E. Washington, D.C. 20426 Reference: Northern Natural Gas Company FERC Docket No. CP24-60-000; Northern Lights 2025 Expansion Project - FERC Order Issuing Certificate and Approving Abandonment (Order) - Request for Temporary Compression