I202609 NOPV

Idaho Public Utilities Commission Brad Little,Governor
P.O. Box 83720, Boise,ID 83720-0074 Edward Lodge,President
John R.Hammond,Jr.,Commissioner
Dayn Hardie,Commissioner
July 9, 2026 Report# I202609
Pat Darras—Vice President of Engineering& Operations Services
Intermountain Gas Company
400 N 41h St.
Bismarck, ND 58501
Dear Mr. Pat Darras,
On July 7ch and 81h, 2026 the Idaho Public Utilities Commission ("Commission"), Pipeline Safety
Division ("Staff'), conducted a field audit of the Pocatello, Idaho District of Intermountain Gas
Company ("IGC")pursuant to Chapter 601 of Title 49, United States Code.
Staff observed that some of the Idaho natural gas system(s) owned and operated by IGC
("Company") was out of compliance on item(s). This results in probable violations of the pipeline
safety regulations Title 49, Code of Federal Regulations, Part 192. The probable violations are as
follows:
PROBABLE VIOLATION(S)
1. 49 CFR 4192.605 Procedural manual for operations, maintenance, and emergencies.
General. Each operator shall prepare and follow for each pipeline, a manual of written
procedures for conducting operations and maintenance activities and for emergency
response. For transmission lines, the manual must also include procedures for handling
abnormal operations. This manual must be reviewed and updated by the operator at
intervals not exceeding 15 months, but at least once each calendar year. This manual must
be prepared before operations of a pipeline system commence. Appropriate parts of the
manual must be kept at locations where operations and maintenance activities are
conducted.
OPS 500 Regulator Inspection and Maintenance
4. REGULATOR INSPECTION AND MAINTENANCE
4.1 Regulators shall be set to lockup at the designated lockup pressure, with some
allowance for lockup fluctuation,but the regulator shall lockup at a pressure equal
to or less than the MAOP.
2. 49 CFR S 192.703 General
(a) No person may operate a segment of pipeline, unless it is maintained in accordance
with this subpart.
IGC POCATELLO FIELD AUDIT PROBABLE VIOLATIONS LETTER— Page 1 of 5

3. 49 CFR U92.739 Pressure limitinp-and regulating stations: Inspection and testing.
(a) Each pressure limiting station, relief device (except rupture discs), and pressure
regulating station and its equipment must be subjected at intervals not exceeding 15
months, but at least once each calendar year, to inspections and tests to detcrmine that it
is—
(1) In good mechanical condition;
(2)Adequate from the standpoint of capacity and reliability of operation for the service
in which it is employed;
(3) Except as provided in paragraph (b) of this section, set to control or relieve at the
correct pressure consistent with the pressure limits of§ 192.201(a); and
(4) Properly installed and protected from dirt, liquids, or other conditions that might
prevent proper operation.
Findinp-W
Regulator station 48725-RS-60058 primary regulator failed due to a damaged seat. The
station was relieving at 59psi when IPUC inspectors and IGC personnel arrived on site.
Reference Photos
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IGC POCATELLO FIELD AUDIT PROBABLE VIOLATIONS LETTER— Page 2 of 5

4. 4 192.463 External corrosion control: Cathodic protection.
(a) Each cathodic protection system required by this subpart must provide a level of
cathodic protection that complies with one or more of the applicable criteria contained in
appendix D of this part. If none of these criteria is applicable, the cathodic protection
system must provide a level of cathodic protection at least equal to that provided by
compliance with one or more of these criteria.
5. Appendix D to Part 192—Criteria for Cathodic Protection and Determination of
Measurements
I. Criteria for cathodic protection—
A. Steel, cast iron, and ductile iron structures.
(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 in accordance with sections 11 and
IV of this appendix.
6. 192.467 External corrosion control: Electrical isolation.
(a) Each buried or submerged pipeline must be electrically isolated from other
underground metallic structures, unless the pipeline and the other structures are
electrically interconnected and cathodically protected as a single unit.
(b) One or more insulating devices must be installed where electrical isolation of a
portion of a pipeline is necessary to facilitate the application of corrosion control.
(c) Except for unprotected copper inserted in ferrous pipe, each pipeline must be
electrically isolated from metallic casings that are a part of the underground system.
However, if isolation is not achieved because it is impractical, other measures must be
taken to minimize corrosion of the pipeline inside the casing.
(d) Inspection and electrical tests must be made to assure that electrical isolation is
adequate.
(e) An insulating device may not be installed in an area where a combustible atmosphere
is anticipated unless precautions are taken to prevent arcing.
(f) Where a pipeline is located in close proximity to electrical transmission tower
footings, ground cables or counterpoise, or in other areas where fault currents or unusual
risk of lightning may be anticipated, it must be provided with protection against damage
due to fault currents or lightning, and protective measures must also be taken at insulating
devices.
OPS 402 External Corrosion Control
4. MONITORING PIPELINES UNDER THE INFLUENCE OF CATHODIC
PROTECTION
4.1. Annual cathodic protection survey locations (test points) shall be selected by
Corrosion Control Department personnel and be located at sufficient locations to
determine the adequacy of cathodic protection and electrical isolation. Consider the
following areas: dead ends of steel mains and transmission lines, areas with known
corrosion, and areas within the system which possess the lowest levels of cathodic
protection.
IGC POCATELLO FIELD AUDIT PROBABLE VIOLATIONS LETTER— Page 3 of 5

4.1.1. A pipe to soil potential survey shall be conducted annually, not to exceed 15
months to determine if the following minimum criteria is achieved.
4.1.1.1. A minimum pipe to soil potential shall be equal, or more electronegative than -
0.850 V DC. Voltage (IR) drops other than those across the stricture-electrolyte
boundary shall be considered for valid interpretation.
4.1.1.1.1. A minimum pipe to soil polarized potential shall be equal, or more
- electronegative than-0.850 V DC. Polarized potentials shall be determined by
interrupting the protective current source(s) or through the use of a cathodic protection
coupon detailed in NACE TM0497 and NACE SP0104.
5. CASINGS (Steel Carrier-Casing Isolation Monitoring and Testing)
5.1. Casings shall be inspected for electrical isolation at least once each calendar year, but
at intervals not exceeding 15 months. Casings that are determined to be shorted or
casings where isolation cannot be determined, shall remain on the shorted casing leak
survey until remedial action or removal is completed (see OPS 706—Leak Survey).
5.6. Shorted casings should be cleared if practical by performing the following actions:
5.6.1. Field Operations:
5.6.1.1. Excavate suspected shorted casing end(s).
5.6.1.2. Inspect the carrier pipe for coating defects and remediate if necessary.
5.6.1.3. Inspect the carrier pipe for structural damage and/or corrosion/pipe wall
loss and remediate if necessary.
5.6.1.4. Remove electrolytes (e.g., water, dirt), damaged casing insulator material,
and/or other conductive materials that may cause the shorted condition.
5.6.1.5. Re-center the carrier pipe inside the casing pipe using approved casing
insulators (non-conductive spacers).
5.6.1.6. Install casing link seals at the ends of the casing to carrier interface.
5.6.2. Corrosion Control personnel:
5.6.2.1. Re-test casing/carrier for electrical isolation after attempts to clear casing
shorts have been performed.
5.6.2.1.1. If testing determines casing is no longer shorted, re-establish
casing on annual casing isolation testing.
5.7. Shorted casings that are not practical to clear shall be scheduled for removal
facilitated by
District Management.
Finding(s):
Carrier and casing 48725-CA-1115928 had a carrier to soil potential reading of-0.696mV
and a casing to soil potential reading of-0.635mV. These values were below the—0.85mV
criteria commonly used to demonstrate adequate cathodic protection with the requirements
of 49 CFR Part 192, Subpart I.This was indicative of a short between the casing and carrier
pipe. No record of remediation or scheduled removal were provided. No records of shorted
casing leak surveys were provided.
IGC POCATELLO FIELD AUDIT PROBABLE VIOLATIONS LETTER— Page 4 of 5

REQUESTED ACTIONS.
A reply to this correspondence is required no later than 45 days from the date of this letter. Please
submit a written reply providing a statement of all relevant facts including a complete description
of the corrective action(s) taken with respect to the above referenced probable violations, and all
actions to be taken to prevent future failures in these areas of concern. This written reply must be
signed by a Company official with authority to bind the Company.
Please send all documents to our office at 11331 W. Chinden Blvd, Boise, Idaho 83714-1021. Be
advised that all material you submit in response to this enforcement action may be a public record
and subject to disclosure under Idaho's Public Records Law. See Idaho Code §§74-101 et seq.
If you wish to dispute any of the above referenced potential violations,you have the right to appear
before the Pipeline Safety Division in an informal conference before August 23,2026,at the above
address. You have the right to present relevant documents and evidence to the Pipeline Safety
Division at that conference. The Pipeline Safety Division will make available to you any evidence
which indicates that you may have violated the law, and you will have the opportunity to rebut this
evidence.See Commission Orders 35095 and 35334,which can be found at https:Hpuc.idaho.gov/.
If you intend to request an informal conference, please contact the Pipeline Safety Division no
later than August 8, 2026.
If you wish to dispute any of the allegations in this Notice,but do not want an informal conference,
you may send the Pipeline Safety Division a written reply to this Notice. This written reply must
be filed with the Commission on or before August 23, 2026, and must be signed by a Company
official with authority to bind the Company. The reply must include a complete statement of all
relevant facts, and all documentation, evidence, and argument the Company submits to refute any
of the above referenced probable violations.
These violations may be subject to any Commission enforcement action as allowed under Idaho
law including, but not limited to, potential civil penalties in accordance with 49 CFR 190.223(a).
If you have any questions concerning this Notice,please contact me at(208)334-0333.All written
responses should be addressed to me at the above address, or you may fax your response to (208)
334-3762.
We appreciate your attention to this matter and your effort to promote pipeline safety.
Sincerely,
Jeff Brooks
Pipeline Safety, Program Manager
Idaho Public Utilities Commission
11331 W.Chinden Blvd.Ste 201-A Boise ID 83714
Telephone:[phone] Facsimile:[phone]
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