20250930Annual Fee Update 2025.pdf

INTERMOUNTAIN" RECEIVED
GAS COMPANY September 30, 2025
A Subsidiary of MDU Resources Group,Inc. I DAH O PUBLIC
In the Community to Serve® UTILITIES COMMISSION
September 30, 2025
Ms. Monica Barrios-Sanchez
Commission Secretary
Idaho Public Utilities Commission
P.O. Box 83720
Boise, ID 83720-0074
RE: Case No. INT-G-23-03 Annual Maintenance Fee Update
Dear Ms. Barrios-Sanchez:
This letter provides the annual update to the Maintenance Fee assessed to RNG producers. As outlined in Case
No. INT-G-23-03, Order No. 35891, Intermountain Gas Company("Intermountain"or"Company")proposed
an annual update to the Maintenance Fee as part of its Renewable Natural Gas ("RNG") Facilitation Plan
("RNG Facilitation Plan")that will be collected from non-utility RNG producers.
The updated Maintenance Fee Intermountain will charge non-utility RNG producers is $4,601 per month,
effective October 1, 2025, through September 30, 2026. As outlined in the RNG Facilitation Plan,
Intermountain will track actual expenses incurred and compare them to the revenue generated by the
Maintenance Fee. The applicable difference, if any,will be applied to next year's Maintenance Fee.
The existing Export Facilities Maintenance Fee ("EFMF") of$5,400 included in the Company's request to
update its RNG Facilitation Plan in Case No. INT-G-23-03 will remain unchanged. As of the date of this filing,
export facilities have not been utilized by an RNG producer. The Company will update the EFMF in its next
annual maintenance fee update when actual Operation and Maintenance ("O&M") costs for a compressor
station and other export facilities are available.
There are currently six RNG producers. Three legacy producers are reimbursing the Company for actual O&M
costs incurred, as outlined in their contracts. The other three RNG producers' contracts conform with the
Company's RNG Facilitation Plan and all subsequent RNG producers requesting access to the Company's
utility system will enter into a contract to comply with the RNG Facilitation Plan.

INTERMOUNTAIN'
GAS COMPANY
A Subsidiary of MDU Resources Group,Inc.
In the Community to Serve®
If you should have any questions regarding this update, please don't hesitate to contact me at(208) 870-2476.
Sincerely,
/s/Zachary Harris
Zachary Harris
Manager, Regulatory Affairs
Intermountain Gas Company
cc: Travis Jacobson
Preston Carter