I202006 NOPV Response

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EXECUTIVE OFFICES
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INTERMOUNTAIN GAS COMPANY '1 ."s _
555 SOUTH COLE ROAD-P.O.BOX 7608• BOISE,IDAHO 83707• [phone]• FAX:[phone]
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October 9,2020
Mr.Darrin Ulmer,Programs Manager
Idaho Public Utility Commission
PO Box 83720
Boise,ID 83720-0074
Subject:Response to Notice of Probable Violations dated September 14,2020(Report# 1202006)
Dear Mr.Ulmer,
This letter is intended to address three probable violations stemming from a field inspection of Intermountain Gas
Company's(IGC)equipment in the Pocatello District conducted July 20-21,2020. Specifically,we are addressing
how we plan to bring the probable violation into full compliance.
PROBABLE VIOLATIONS
1. 49 CFR�192.739(a)(4)Pressure limiting and regulating stations: Inspection and testing.
Pressure limiting and regulating stations: Inspection and testing—reads:Properly installed and
protected from dirt, liquids, or other conditions that might prevent proper operation. Which is
also covered in IGC Procedure 4306 Sec 4.1.1.
Finding:
During the inspection it was noted that regulator stations 60020(primary)had one of its regulators fail
to lock up at the pre-established set point preventing proper operation.Also stations 60002 and 60007
were unable to be locked up due to irrigation pumps running.
Intermountain Gas Response
IGC acknowledges the findings brought forth by the IPUC stated above. The following table was extracted
from the annual inspection questions, Regulator I Operated Properly and Regulator 2 Operated Properly.
While the results do not indicate a history of lockup failures, a white,powdery substance was identified at this
location during the 2018 and 2020 annual inspections. As such,regulator station 60020 was added to the IGC
Failed to Lockup Mitigation Plan and is currently scheduled to have pilot sulfur filtration installed in 2021.
Regulator 2017 2017 2018 2018 2019 2019 2020 2020 Add to
Station Reg 1 Reg 2 Reg 1 Reg 2 Reg 1 Reg 2 Reg 1 Reg 2 Plan
60020 Yes Yes Yes Yes Yes Yes Yes Yes Yes
Additionally, it is identified in the IPUC findings that regulator stations 60002 and 60007 were unable to lock-
up due to irrigation pumps running. The constant load of the irrigation pumps does not allow for the necessary
duration of shut in to properly demonstrate lockup while the pumps are running. When tested with the irrigation
pumps shut off,we are able to demonstrate lockup successfully.

EXECUTIVE OFFICES
INTERMOUNTAIN GAS COMPANY
555 SOUTH COLE ROAD-P.O.BOX 7608• BOISE,IDAHO 83707• [phone]• FAX:[phone]
2. 49 CFR 4192.481(a)(b)(c)Atmospheric corrosion control: monitoring.(a)Each operator must
inspect each pipeline or portion of pipeline that is exposed to the atmosphere for evidence of
atmospheric corrosion. (b)During inspections the operator must give particular attention to pipe at
soil-to-air interfaces, under thermal insulation, under disbanded coatings, at pipe supports, in splash
zones, at deck penetrations, and in spans over water. (c)If atmospheric corrosion is found during an
inspection, the operator must provide protection against the corrosion as required by§192.479.
Cascade Natural Gas Corporation-OPS 610(Sec 2.1,2.2 and 2.2.5),2.1-reads: Transmission and
distribution pipelines shall be patrolled, as necessary, to observe factors affecting safe operation
and to enable correction to potentially hazardous conditions. In addition to visual evidence of
leakage,patrol considerations should include observation and reporting ofpotential hazards. 2.2-
reads: Factors affecting safe operation include: 2.2.5-reads: Exposed pipe conditions including
atmospheric corrosion,physical deterioration of exposed piping,pipeline spans, and structural
pipeline supports such as bridges,pilings, headwalls, casings, and foundations.
Finding:
Pipeline patrol ACP827-002 and ACP 827-004 appeared to have issues with coatings and possible
contact with hanger on bridge.
Intermountain Gas Response
IGC acknowledges the findings brought forth by the IPUC stated above.Pipeline patrol ACP 827-002 indicated
contact with a hanger and as such, the inspection interval was reduced from every 3 calendar years to not
exceeding 7.5 months,but at least twice each calendar year.In addition,what initially appeared to be corrosion,
was later confirmed to be coal tar wrap.
With regard to pipeline patrol ACP 827-004,while there was no contact with a hanger and no corrosion found,
there were areas of paint loss at points with surface oxidation. The need to paint will be reevaluated during
future inspection.
3. 49 CFR 4 Appendix D of Part 192—Criteria for Cathodic Protection and determination of
measurements.
I. Criteria for cathodic protection—A. Steel... (1)A negative (cathodic) voltage of at least 0.85
volt, with reference to a saturated copper-copper sulfate half-cell. Determination of this voltage
must be made with the protective current applied, and IAW sections II and IV of this appendix.
Findinll•
During the inspection it was noted that at the following locations CP readings were unable to be
ascertained: Casings 827-00-606 and 827-00-501. CP technician informed us that one already has a
leak survey taking place and the other will be scheduled upon completion of the inspection.
Intermountain Gas Response
IGC acknowledges the findings brought forth by the IPUC stated above and respectfully maintains that cathodic
protection (CP) reads at casings 827-00-606 and 827-00-501 are achievable; however, both casings appear to be
shorted and are being leak surveyed per company procedure. Casing 827-00-501 has not officially been diagnosed
as shorted, but a leak survey took place on July 24, 2020 and will continue per company procedure until a
determination can be made.

EXECUTIVE OFFICES
INTERMOUNTAIN GAS COMPANY
555 SOUTH COLE ROAD-P.O.BOX 7608• BOISE,IDAHO 83707•[phone]•FAX:[phone]
Please contact Josh Sanders at(701)222-7773 with questions or comments.
Respectfully Submitted,
Pat Darras
Vice President, Engineering& Operations Services
Intermountain Gas Company