I202310 LOC Response

EXECUTIVE OFFICES
INTERMOUNTAIN GAS COMPANY
555 SOUTH COLE ROAD-P.O.BOX 7608• BOISE,IDAHO 83707•[phone]• FAX:[phone]
November 15,2023
Mr.Jeff Brooks,Programs Manager
Idaho Public Utility Commission
PO Box 83720
Boise,ID 83720-0074
Subject:Response to Letter of Concern dated October 19,2023 (Report#I202310)
Dear Mr.Brooks,
This letter is intended to address four(4)areas of concern stemming from a procedural,records,and field inspection
conducted by the Idaho Public Utilities Commission(IPUC)on October 16,2023,and October 18,2023,of
Intermountain Gas Company's(IGC)Rexburg LNG Plant.
PROBABLE VIOLATIONS
L 49 CFR 8 193.607 Foreign Material
(b)LNG plant grounds must be free from rubbish,debris,and other material which present a fire
hazard.Grass areas on the LNG plant grounds must be maintained in a manner that does not present
a fire hazard.
Findin¢(s)•
Weeds within the facility need to be sprayed and pulled to prevent fire hazards.
Intermountain (:as Response
IGC acknowledges the findings brought forth by the IPUC. IGC utilizes a contractor for weed care that is on a
seasonal schedule. The contractor typically performs weed care once a season, or more upon request. The
contractor was behind on the 2023 fall schedule.The contractor sprayed and pulled weeds on October 25,2023.
2. 49 CFR S 193.2609 Sunnort Systems
Each support system or foundation of each component must be inspected for any detrimental change
that could impair support.
Finding(s)•
All tank saddles/supports are showing signs of cracking and measures to prevent further degradation need to
be taken.
Intermountain (:as Resnonse
IGC acknowledges the findings brought forth by the IPUC. IGC has contacted a third-party engineering
company to discuss a repair and maintenance plan for tank saddles and supports.

EXECUTIVE OFFICES
INTERMOUNTAIN GAS COMPANY
555 SOUTH COLE ROAD-P.O. BOX 7608• BOISE,IDAHO 83707•[phone]• FAX:[phone]
3. 49 CFR 8 193.2613 Auxiliary Hower sources
Each auxiliary power source must be tested monthly to check its operational capability and tested
annually for capacity. The capacity test must take into account the power needed to start up and
simultaneously operate equipment that would have to be served by that power source in an
emergency.
Findin¢(s)•
Procedure 4558 Rexburg LNG Fire Equipment Maintenance Step 2.5.4. The engine generator will be started
and run once per month.The verbiage"and tested annually for capacity",needs to be added as required.
Intermountain Gas Resnonse
IGC acknowledges the findings brought forth by the IPUC. An MOC has been initiated to add additional
language to procedure 4558 Rexburg LNG Fire Equipment Maintenance to incorporate the requirements for
annual capacity testing as outlined in 49 CFR § 193.2613.
4. 49 CFR 6 193.250.5 Cooldown
(b)After cooldown stabilization is reached,cryogenic piping systems must be checked for leaks in
areas of flanges,valves,and seals.
Finding(s)•
This verbiage needs to be added to the Daily Plant checklist(b)After cooldown stabilization is reached,
cryogenic piping systems must be checked for leaks in areas of flanges,valves,and seals.
Intermountain Gas Resnonse
IGC acknowledges the findings brought forth by the IPUC. The Daily Plant checklist has been updated to
incorporate the requirement for leak checks on cryogenic piping systems when cooldown stabilization is
reached as outlined in 49 CFR § 193.2505.
Please contact Josh Sanders at(701)222-7773 with questions or comments.
Respectfully Submitted,
/UG 4-t-D✓L
Pat Darras
Vice President,Engineering& Operations Services
Intermountain Gas Company