20260910Summons_FormalComplaint_Attachments.pdf

�TILIT/�S
jpIx �, Idaho Public Utilities Commission Brad Little,Governor
P.O. Box 83720, Boise,ID 83720-0074 Edward Lodge,President
John R.Hammond,Jr.,Commissioner
•1913 Dayn Hardie,Commissioner
September 10, 2026
Via Certified Mail
Pat Darras—Vice President of Engineering & Operations Services
Intermountain Gas Company
400 N. 41h Street
Bismarck,ND 58501
Re: IPUC Case No. INT-G-26-08
Commission Staff s Formal Complaint Concerning Intermountain Gas Co.
To Whom It May Concern,
Enclosed please find a Summons and Formal Complaint issued against Intermountain Gas
Company in the above-mentioned case. As directed in the Summons, you are to file a written
answer or motion in defense of said Complaint with this Commission within twenty-one(21) days
of the service date of the Summons.
Sincerely,
Monica Barrios-Sanchez
Commission Secretary
Enclosure(s)
11331 W.Chinden Blvd.Ste 201-A Boise ID 83714
Telephone:[phone] Facsimile:[phone]

BEFORE THE IDAHO PUBLIC UTILITIES COMMISSION
STAFF OF THE IDAHO PUBLIC UTILITIES )
COMMISSION, PIPELINE SAFETY ) CASE NO. INT-G-26-08
DIVISION, )
COMPLAINANT, ) SUMMONS
VS. )
INTERMOUNTAIN GAS COMPANY, )
RESPONDENT. )
Pat Darras—Vice President of Engineering & Operations Services
Intermountain Gas Company
400 N. 41h Street
Bismarck,ND 58501
THE STATE OF IDAHO SENDS GREETINGS TO THE ABOVE-NAMED RESPONDENT
YOU ARE HEREBY NOTIFIED that a Complaint has been filed with the Idaho
Public Utilities Commission by the above-named Complainant; and
YOU ARE HEREBY DIRECTED to file a written answer or written motion in
defense of the Complaint within twenty-one (21) days of the service date of this Summons.
YOU ARE FURTHER NOTIFIED that unless you do so within the time herein
specified, the Idaho Public Utilities Commission may take such action against you as is prayed
for in the Complaint or as it deems appropriate under Title 61 of the Idaho Code.
WITNESS my hand and the seal of the Idaho Public Utilities Commission this loth
day of September 2026.
Jam:•. .�0 •G �''► �A" a.i
i oni a Ba -S ch
lea[
Commission Secretary
.,•,qp� OF 10��.•`
SUMMONS 1

JEFFREY R. LOLL
DEPUTY ATTORNEY GENERAL
IDAHO PUBLIC UTILITIES COMMISSION
PO BOX 83720
BOISE, IDAHO 83702
[phone]
IDAHO BAR NO. 11675
jef.lolIg]2uc.idaho.gov
Attorney for the Commission Staff
BEFORE THE IDAHO PUBLIC UTILITIES COMMISSION
IN THE MATTER OF COMMISSION STAFF'S )
FORMAL COMPLAINT CONCERNING ) CASE NO. INT-G-26-08
CONTINUED SAFETY VIOLATIONS WITHIN )
INTERMOUNTAIN GAS COMPANY'S )
NATURAL GAS PIPELINE SYSTEM AT THE ) FORMAL COMPLAINT
NAMPA DISTRICT AND REGULATOR )
STATION 48371-RS-59980 )
The Staff of the Idaho Public Utilities Commission ("Commission"), Pipeline Safety
Division ("Staff'), by and through its attorney of record, Jeffrey Loll, Deputy Attorney General,
files this Formal Complaint under Commission Rule of Procedure 54 concerning continued safety
violations within Intermountain Gas Company's ("Company") natural gas pipeline system at the
Company's Nampa District and Regulator Station 48371-RS-59980.
Staff requests that the Commission enter an Order, requiring the Company to pay a penalty
to be determined by the Commission, consistent with Commission authority under Idaho Code §§
61-501, 61-515 and 61-701 et seq.
JURISDICTION
1. The Company is a gas corporation and a public utility, and the Commission has
jurisdiction over it and the issues in this case under Title 61,Idaho Code. See Idaho Code §§ 61-117,
61-129, 61-501, 61-503, and 61-515.
2. When a complaint is filed concerning the safety and adequacy of a public utility's
FORMAL COMPLAINT-1

service the Commission has the power and authority to investigate the matter and require the"public
utility to maintain and operate its line, plant, system, equipment, apparatus and premises in
such manner as to promote and safeguard the health and safety of its employees, customers
and the public[.]"Idaho Code § 61-515; see also Idaho Code § 61-302.
3. Pursuant to Idaho Code § 61-515 on June 30, 2021, the Commission issued
Order No. 35095 in Case No. GNR-U-21-01, adopting the Commission's Safety and Accident
Report Rules for Utilities Regulated by the Idaho Public Utilities Commission. Order No. 35095
at 2. Rule 201 of these Rules incorporates by reference Part 260.9, Title 18 and Parts 191, 192,
193, 195, and 199, Title 49 of the Code of Federal Regulations ("CFR") concerning the minimum
federal pipeline safety standards.
4. Idaho Code§ 61-701 et. seq. provides the Commission with the authority to enforce
"the constitution and statutes of this state affecting public utilities,the enforcement of which is not
specifically vested in some other office or tribunal" and to seek the imposition of penalties for
violations of these authorities if deemed necessary.
BACKGROUND
5. Paragraphs 1 through 4 above are incorporated herein by this reference as though fully
set forth in this paragraph.
6. On April 8-9, 2024, Staff conducted an annual field audit consisting of procedural,
records, and field observations of the Company's Nampa district.
7. On April 16,2024,as a result of the April 8-9 audit, Staff sent the Company Notice
of Probable Violation ("NOPV") Report No. 1202405. NOPV Report No. 1202405, a copy of
which is attached to this Formal Complaint as Attachment A, consisted of two separate violations
of Title 49 CFR Part 192 regarding failure to lock up due to oil at Regulator Station 48371-RS-
59980. Staff accepted the Company's corrective response dated May 23, 2024, and closed NOPV
Report No. 1202405 on August 15, 2024.
8. On May 27-28, 2025, Staff conducted an annual field audit consisting of
procedural, records, and field observations of the Company's Nampa district.
9. On June 17, 2025, as a result of the May 27-28 audit, Staff sent the Company
NOPV Report No. 1202504.NOPV Report No.1202504,a copy of which is attached to this Formal
Complaint as Attachment B, consisted of two separate violations of Title 49 CFR Part 192
FORMAL COMPLAINT-2

regarding failure to lock up due to oil at Regulator Station 48371-RS-59980. Staff accepted the
Company's corrective response dated July 31, 2025, and closed NOPV Report No. I202504 on
August 4, 2025.
10. As part of its corrective response dated July 31, 2025, the Company committed to
conducting quarterly (rather than annual) internal inspections at Regulator Station 48371-RS-
59980 until implementing a mitigation plan.
11. The ongoing quarterly inspections,the results of which are submitted to Staff,have
routinely found oil at Regulator Station 48371-RS-59980. A copy of the quarterly inspection
findings submitted to Staff is attached to this Formal Complaint as Attachment C.
12. On May 26-27, 2026, Staff conducted an annual field audit consisting of
procedural, records, and field observations of the Company's Nampa district.
13. On June 2, 2026, as a result of May 26-27 audit, Staff sent the Company NOPV
Report No. I202608. NOPV Report No. I202608, a copy of which is attached to this Formal
Complaint as Attachment D, consisted of three separate violations of Title 49 CFR Part 192
regarding failure to lock up due to oil at Regulator Station 48371-RS-59980.
14. On July 1, 2026, the Company responded to NOPV Report No. I202608. A copy of
the response is attached to this Formal Complaint as Attachment E.In addition to quoting its response
to NOPV Report No. I202504, which was submitted to Staff on July 31, 2025, the Company stated
that it was continuing to work with Williams Northwest Pipeline to install a coalescent filter at the
Nampa Gate designed to remove the oil preventing lock-up at Regulation Station 48371-RS-59980.
VIOLATIONS
Violations of Title 49 CFR Part 192
15. Paragraphs I through 14 above are incorporated herein by this reference as though
fully set forth in this paragraph.
16. As provided in NOPV No. I202608, the Company violated the following code
sections: (1) 49 CFR § 192.605, resulting from a violation of the Company's required procedural
manual,OPS 500,a copy of which is attached to this Formal Complaint as Attachment F;(2)49 CFR
§ 192.703; and(3)49 CFR§ 192.739.Regulator Station 4837 1-RS-59980 has failed to limit pressure
due to oil entrained in the gas stream and fouling the equipment through three consecutive annual
Staff field audits and multiple internal quarterly inspections. See Attachments A—D.
FORMAL COMPLAINT-3

PROPOSED ACTION
Civil Penalty Under 49 CFR 190.223
17. Paragraphs 1 through 16 above are incorporated herein by this reference as though
fully set forth in this paragraph.
18. As a direct and proximate result of the Company's failures, it could be subject to a
penalty of up to $272,926 for each of the above violations for each day that the violation persists up
to a maximum amount of$2,729,245.Idaho Code § 61-712A; 49 CFR 190.223.
19. Staff accepted the proposed corrective actions in the Company's response to NOPV
Nos. I202405 and I202504 based on the understanding that the Company would resolve the oil
problem at Regulator Station 48371-RS-59980 within a reasonable timeframe.
20. Given the persistence of the oil problem at Regulator Station 48371-RS-59980
through three consecutive annual Staff field audits and multiple internal quarterly inspections, Staff
believes the Company has failed to rectify the issue within a reasonable timeframe and is not confident
that the Company will take the steps necessary to solve the problem of its own accord.
21. Staff recommends the Commission impose the maximum allowable civil penalty
amount to help promote code compliance and enhance public safety in Idaho.
PRAYER FOR RELIEF
WHEREFORE, the Plaintiffs pray for entry of a Commission order:
I. Imposing the maximum civil penalty amount available under Idaho Code § 61-
712A as determined by the Commission; and
2. For such other and further relief as the Commission may deem just and appropriate.
Staff stands ready for any additional briefing, hearing, or other proceedings deemed
necessary by the Commission.
DATED this 10th day of September 2026.
J,effre R. Loll
Deputy Attorney General
FORMAL COMPLAINT-4

ATTACHMENT A

Idaho Public Utilities Commission Brad Little,Governor
P.O.Box 83720,Boise,ID 83720.0074 Eric Anderson,President
John R.Hammond,Jr.,Commissioner
Edward Lodge,Commissioner
April 16, 2024 Report#I202405
Pat Darras—Vice President of Engineering& Operations Services
Intermountain Gas Company
400 N 4a' St.
Bismarck,ND 58501
Dear Mr. Darras:
On April 8-9, 2024, the Idaho Public Utilities Commission ("Commission"), Pipeline Safety
Division ("Staff'), conducted a Field inspection in the Nampa 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 distribution system owned and operated by IGC
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 VIOLATIONS)
1. 192.605 Procedural manual for operations, maintenance, and emergencies.
(a) 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 Station Inspection and Maintenance
4.1. Regulators shall be set to lockup at the designated set pressure, unless setting during
flow conditions allows the regulator to lockup at a pressure equal to or less than the
MAOP. For example, a regulator may be set during flow conditions provided the set
pressure plus the known droop (e.g., the difference between lockup and delivery
pressure) does not exceed MAOP.
IGC NAMPA FIELD INSPECTION PROBABLE VIOLATIONS LETTER—PAGE 1
INT-G-26-08
Attachment A
Page 1 of 3

2. 49 CFR 4192.739 (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.
Finding(s)•
Regulator station 48371-RS-1289867 (Dithiazine), 48371-RS-59980 (oil), 48371-RS-
59992, 48371-RS-59976 (metal shavings) failed to lock up on the primary side and
48371-RS-59977 (weld slag) on the secondary side. Metal shavings, compressor oil or
Dithiazine debris were found in the diaphragms and regulator bodies when disassembled.
All issues were fixed on-site upon disassembly, debris removal, and were then retested
with adequate lock up.
REOUESTED 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 an IGC 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 May 31, 2024, 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://puc.idaho.gov/. If you intend to request an informal conference,please contact the Pipeline
Safety Division no later than May 16, 2024.
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 May 31, 2024, and must be signed by an IGC official
with authority to bind the company. The reply must include a complete statement of all relevant
facts, and all documentation, evidence, and argument IGC submits to refute any of the above
referenced probable violations.
IGC NAMPA FIELD INSPECTION PROBABLE VIOLATIONS LETTER—PAGE 2
INT-G-26-08
Attachment A
Page 2 of 3

If you do not respond to this notice by May 31, 2024, you may be subject to any Commission
enforcement action as allowed under Idaho law, including but not limited to, potential civil
penalties of up to two hundred thousand($200,000). See Idaho Code §61-712A.
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,
/-A-Y��
Jeff Brooks
Pipeline Safety, Program Manager
Idaho Public Utility Commission
11331 W.Chinden Blvd.Ste 201-A Boise ID 83714
Telephone:[phone] Facsimile:[phone]
IGC NAMPA FIELD INSPECTION PROBABLE VIOLATIONS LETTER—PAGE 3
I NT-G-26-08
Attachment A
Page 3 of 3

ATTACHMENT B

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
June 17, 2025 Report# I202504
Pat Darras—Vice President of Engineering & Operations Services
Intermountain Gas Company
400 N 41h St.
Bismarck,ND 58501
Dear Mr. Pat Darras:
On May 27 and 28, the Idaho Public Utilities Commission ("Commission"), Pipeline Safety
Division ("Staff'), conducted a field audit of the Nampa 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 VIOLATIONS)
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.
IGC NAMPA FIELD AUDIT PROBABLE VIOLATIONS LETTER— Page 1 of 4
1 NT-G-26-08
Attachment B
Page 1 of 4

2. 49 CFR 4192.739 Pressure limiting 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 determine that it
is—
(1) In good mechanical condition;
(4) Properly installed and protected from dirt, liquids, or other conditions that might
prevent proper operation.
OPS 500 Regulator Inspection and Maintenance
4. REGULATOR INSPECTION AND MAINTENANCE
1.1 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.
Finding(s)•
During the 2025 Nampa District Field Audit, IPUC Inspectors observed Regulator Station 48371-
RS-59980 fail the lock up test on the primary regulator due to oil and metal shavings. This is the
second failure in two consecutive years during an IPUC audit.
3. 49 CFR 4192.747 Valve Maintenance: Distribution systems.
(b) Each operator must take prompt remedial action to correct any valve found inoperable,
unless the operator designates an alternative valve.
OPS 703 Valve Inspection and Maintenance
4. Valves that require maintenance (see Section 3) found inaccessible and/or inoperable
must be remedied. The remediation shall be completed prior to the compliance date for
the maintenance.
4.1. Inaccessible and inoperable valves that separate Emergency Shutdown
Sections as defined in OPS 704 — Emergency Shutdown Sections, shall have an
alternative valve that is accessible and operable designated in the place of
inoperable valves. (Legacy terms for Emergency Shutdown Sections include
Shutdown Areas, E-Valve Districts, Sectionalizing Plans, Key Valves, etc.). If
applicable, the change will be recorded in the district Emergency Shutdown Plans.
4.1.2. Local Field Operation Management, or designee, shall submit an
ENGMOC to report inaccessible and inoperable Emergency Shutdown
Section valves as soon as practical, but no later than the next business day.
IGC NAMPA FIELD AUDIT PROBABLE VIOLATIONS LETTER— Page 2 of 4
INT-G-26-08
Attachment B
Page 2 of 4

9. Maintenance Criteria
9.1 In addition to the inspection criteria listed in Section 8, partially operate
Transmission, Distribution, and Service Line Valves that meet the criteria of
Section 3.3 and 3.4.
9.1.6 If a plug valve does not operate or is not adequately lubricated, apply
valve sealant per the requirements of Section 7 and then partially
operate the valve. (Inability to operate without significant force is an
indication of inadequate lubrication.)
9.1.6.1 If the valve won't accept sealant or will not operate after
injecting sealant, inject a valve flush/cleaner. After
flushing/cleaning, inject new sealant. Refer to Section 7.
9.1.6.2 If after flushing/cleaning and injecting new sealant, the valve
is operational but requires two (2) persons to operate, and the
GIS Gas Valve Attribute Two Man Operate is N/A or No,
notify Field Operations Management.
Findinp(s)•
During the 2025 Nampa District Field Audit, IPUC Inspectors identified that valves 48317-VLV-
32633, 48317-VLV-32638, and 48317-VLV-32840, classified as"one-man"valves,required two
valve technicians for operation. However, these valves were not designated as "two-man" valves
in Maximo. Prior to operation, sealant was not injected, nor were the valves flushed or cleaned,
despite requiring significant force and the assistance of two technicians. These actions were not in
compliance with OPS 703 Section 9.1.6.
It was confirmed through IGC Compliance Personnel that the valve technicians reported the
inoperable emergency valves (48317-VLV-32633, 48317-VLV-32638 and 48317-VLV-32840)
within the required timeframe as stated in OPS 703 Section 4.1.1. OPS Section 4.1.2 was not
followed. An ENGMOC was not created within one business day of notification. Per IGC
Compliance Personnel,the valves were designed"two-man"valves in Maximo and an ENGMOC
was created on May 29, 2025.
IGC NAMPA FIELD AUDIT PROBABLE VIOLATIONS LETTER— Page 3 of 4
1 NT-G-26-08
Attachment B
Page 3 of 4

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 1,2025, 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://puc.idaho.gov/.
If you intend to request an informal conference, please contact the Pipeline Safety Division no
later than July 17, 2025.
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 1, 2025, 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]
IGC NAMPA FIELD AUDIT PROBABLE VIOLATIONS LETTER— Page 4 of 4
INT-G-26-08
Attachment B
Page 4 of 4

Location
Work Order District City Legacy ID Location Location Description
WO12095514 NAMPA NAMPA 30059 48371-RS-59980 REGULATOR STATION S SIDE OF CHERRY LN 1300' E OF NORTHSIDE BLVD
WO12224296 NAMPA NAMPA 30059 48371-RS-59980 REGULATOR STATION S SIDE OF CHERRY LN 1300' E OF NORTHSIDE BLVD
WO12224294 NAMPA NAMPA 30059 48371-RS-59980 REGULATOR STATION S SIDE OF CHERRY LN 1300' E OF NORTHSIDE BLVD
WO12346443 NAMPA INAMPA 30059 48371-RS-59980 REGULATOR STATION S SIDE OF CHERRY LN 1300' E OF NORTHSIDE BLVD
WO12431623 NAMPA NAMPA 30059 48371-RS-59980 REGULATOR STATION S SIDE OF CHERRY LN 1300' E OF NORTHSIDE BLVD
WO12512416 NAMPA NAMPA 30059 48371-RS-59980 REGULATOR STATION S SIDE OF CHERRY LN 1300' E OF NORTHSIDE BLVD
WO12547609 NAMPA NAMPA 30059 48371-RS-59980 REGULATOR STATION S SIDE OF CHERRY LN 1300' E OF NORTHSIDE BLVD

REGULATOR
REGULATOR LOCK LOCKED UP REGULATOR
UP PRESSURE AS PROPERLY OPERATED
Asset Number Asset Description Tool Serial# Work Type Actual Finish Owner External Owner FOUND AS FOUND PROPERLY
10127138 GAS,REGULATOR CM 6/3/2025 DCALL CALLD-001868 331.000 YES YES
10127138 GAS,REGULATOR CM 9/11/2025 DCALL CALLD-001868 329.000 YES YES
10127138 GAS,REGULATOR CM 9/11/2025 DCALL CALLD-001868 329.000 YES YES
10127138 GAS,REGULATOR CM 12/10/2025 DCALL CALLD-001868 336.000 YES YES
10127138 GAS,REGULATOR CM 3/13/2026 DCALL CALLD-001868 332.000 YES YES
10127138 GAS,REGULATOR CM 4/3/2026 DCALL CALLD-001868 332.000 YES YES
10127138 GAS,REGULATOR 50534 CM 5/27/2026 DCALL CALLD-001868 329.000 YES YES

DOES REGULATOR REGULATOR
REGULATOR LOCKUP LOCKED UP REQUEST 90
PILOT FILTER WAS OIL NEED TO BE PRESSURE AS PROPERLYAS DAY FOLLOW-
INSPECTED PRESENT REBUILT LEFT LEFT UP FOR OIL COMMENTS
FOUND OIL IN BODYAND FILTER OF PRIMARY REG, REBUILT
REG AND CLEANED OUT REG BODYAND FILTER, NOW IN
ACCEPTABLE YES YES 331.000 YES YES GOOD WORKING ORDER
FOUND OIL IN PRIMARY REG,CLEANED OUT REG BODY AND
ACCEPTABLE YES NO 329.000 YES YES PILOT FILTER
FOUND OIL IN PRIMARY REG,CLEANED OUT REG BODYAND
ACCEPTABLE YES NO 329.000 YES YES PILOT FILTER
ACCEPTABLE YES NO 336.000 YES NO DRAINED OILL OUT OF PILOT FILTER
FOUND OIL ON TOP OF BOOT AND IN PILOT AND PILOT
FILTER, REPLACED PILOT FILTER AND CLEANED OPUT REG
ACCEPTABLE YES NO 332.000 YES AND PILOT.
REBUILT PRIMARY REG WHILE DOING THE ANNUAL REG
ACCEPTABLE YES NO 332.000 YES STATION TESTING
FOUND OIL IN PILOTAND IN REG BODY, REPLACED BOOT
ACCEPTABLE YES NO 329.000 YES AND CLEANED OUT PILOT AND REG BODY

ATTACHMENT D

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
June 2, 2026 Report#I202608
Pat Darras—Vice President of Engineering & Operations Services
Intermountain Gas Company
400 N 4th St.
Bismarck, ND 58501
Dear Mr. Pat Darras,
On May 26 and 27, 2026 the Idaho Public Utilities Commission("Commission"), Pipeline Safety
Division ("Staff'), conducted a field audit of the Nampa 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 4 192.703 General
(a) No person may operate a segment of pipeline, unless it is maintained in accordance
with this subpart.
IGC NAMPA FIELD AUDIT PROBABLE VIOLATIONS LETTER— Page 1 of 4
INT-G-26-08
Attachment D
Page 1 of 4

3. 49 CFR 4192.739 Pressure limiting 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 determine 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.
Finding(s)
Regulator stations 48371-RS-59980 and 48283-RS-59707 primary regulators failed to achieve
lock-up. Oil was preventing lockup at Regulator station 48371-RS-59980 for the third
consecutive year during IPUC field audits. Debris was found in Regulator station 48283-RS-
59707 which failed due to heavy debris fouling.
©89°E(T).43.W5 6.4731,$6 t4ft P2454ft
14
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Debris Fouling Overview 48283-RS-59707 Debris Fouling Closeu 48283-RS-59707
IGC NAMPA FIELD AUDIT PROBABLE VIOLATIONS LETTER— Page 2 of 4
1 NT-G-26-08
Attachment D
Page 2 of 4

11 330. 1 :1 1
©317"N W(T)• 43.619468,-116.568295 t9ft ♦ 180 O 240*SW(T) 43.619478,-116.568276±9ft ♦ 2418ft
17
4 _ .
Overview (oil) 48371-RS-59980 Closeu (oil) 48371-RS-59980
IGC NAMPA FIELD AUDIT PROBABLE VIOLATIONS LETTER— Page 3 of 4
INT-G-26-08
Attachment D
Page 3 of 4

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 corrcctive 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 July 17, 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://puc.idaho.gov/.
If you intend to request an informal conference, please contact the Pipeline Safety Division no
later than July 2, 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 July 17, 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,
//I--
JeffBrooks
Pipeline Safety, Program Manager
Idaho Public Utilities Commission
11331 W.Chinden Blvd.Ste 201-A Boise ID 83714
Telephone:[phone] Facsimile:[phone]
IGC NAMPA FIELD AUDIT PROBABLE VIOLATIONS LETTER— Page 4 of 4
I NT-G-26-08
Attachment D
Page 4 of 4

ATTACHMENT E

EXECUTIVE OFFICES
INTERMOUNTAIN GAS COMPANY
555 SOUTH COLE ROAD-P.O.BOX 7608• BOISE,IDAHO 83707•[phone]• FAX:[phone]
July 1,2026
Mr.Jeff Brooks,Programs Manager
Idaho Public Utility Commission
PO Box 83720
Boise,ID 83720-0074
Subject:Response to the Notice of Probable Violation dated June 2,2026(Report#1202608)
Dear Mr.Brooks,
This letter is intended to address one(1)notice of probable violation stemming from a field audit conducted by the
Idaho Public Utilities Commission(IPUC)May 26-27,2026,of Intermountain Gas Company's(IGC)Nampa
District pursuant to Chapter 601 Title,49 United States Code.
PROBABLE VIOLATION
1. 49 CFR 8 192.605 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 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.
3. 49 CFR 8 192-739 Pressure]* 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 to intervals not exceeding 15 months,but at least once each
calendar year,to inspections and tests to determine that it is-
(1) In good mechanical condition.
(2) Adequate from the standpoint of capacity and reliability for the service in which it is
employed.
(3) Except as provided in paragraph(b)of this section,set to control or relive 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.
Finding(sl•
Regulator Station 48731-RS-59980 and 48283-RS-59707 primary regulator failed to achieve lock-up. Oil was
preventing lockup at Regulator station 48371-RS-59980 for the third consecutive year during IPUC field audits.
Debris was found in Regulator station 48283-RS-59707 which failed due to heavy debris fouling.
I NT-G-26-08
Attachment E
Page 1 of 3

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EXECUTIVE OFFICES
INTERMOUNTAIN GAS COMPANY
555 SOUTH COLE ROAD-P.O.BOX 7608•BOISE,IDAHO 83707•[phone]•FAX:[phone]
intermountain Gas Resnonse
Regulator Station 48283-RS-59707: The regulator was disassembled, cleaned, and reassembled onsite and
subsequently locked up properly.No previous issues have been identified at this location.The primary regulator locked
up as expected during the 2026,2025,2024,2023,and 2022 annual inspections.
Regulator Station 4873 1-RS-59980:As stated in previous response to NOPV I202504,submitted to the IPUC July 31,
2025,
IGC has been in communication with Williams to determine solutions to mitigate the oil. IGC is currently
reviewing and has recently proposed to Williams the installation of a coalescent filter at the Nampa Gate.Per
response from Williams, they willperform meter maintenance within the next 3-4 weeks, which will include
the collection and testing of contaminants. Based on the results, Williams will work with manufacturers to
determine the appropriate filter technology for optimum removal of contaminants(e.g., oil).
Until a mitigation plan is developed and implemented,IGC will increase the inspection frequency from annual
to quarterly at Regulator Station 483 71-RS-59980.
On August 4,2025, IGC received a closure letter from the IPUC accepting the response and corrective actions. On
June 2,2026, IGC provided updates to the IPUC via email. IGC confirmed it is continuing quarterly inspections at
Regulator Station 4837 1-RS-59980 and actively working with Williams Northwest Pipeline on the installation of the
coalescent filter.
Please contact Josh Sanders at(701)222-7773 with questions or comments.
Respectfully Submitted,
�Ua.r'�
Pat Darras
Vice President, Engineering& Operations Services
Intermountain Gas Company
I NT-G-26-08
Attachment E
Page 3 of 3

ATTACHMENT F

POLICY STATEMENT OPS 500
Cascade Natural Gas Corporation Regulator Station Inspection and Status: Released
Great Plains Natural Gas Co. Maintenance Revision Date: Oct.28,2024
Intermountain Gas Company OPSMOC-2215&2217
Montana-Dakota Utilities Co. Page 1 of 14
PURPOSE
To provide procedures for the inspection and maintenance of regulating stations within the MDU Utilities
Group (MDUG) pipeline system.
REFERENCES
External References:
49 CFR§ 192.195- Protection Against Accidental Over-Pressuring
49 CFR§ 192.199- Requirements for Design of Pressure Relief and Limiting Devices
49 CFR§ 192.201 - Required Capacity of Pressure Relieving and Limiting Devices
49 CFR§ 192.605 (b)(5)- Procedural Manual for Operations, Maintenance, and Emergencies
49 CFR§ 192.619- Maximum Allowable Operating Pressure - Steel or Plastic Pipelines
49 CFR§ 192.621 - Maximum Allowable Operating Pressure - High Pressure Distribution Systems
49 CFR§ 192.739- Pressure Limiting and Regulating Stations - Inspection and Testing
49 CFR§ 192.741 - Pressure Limiting and Regulating Stations -Telemetering or Recording
49 CFR§ 192.743- Pressure Limiting and Regulating Stations - Capacity of relief devices
PHMSA Interpretations (PI)92-034 (192.195)and 14-0016 (192.621)
Internal References:
OPS 313—Gas Facility Protection.
OPS 501 — Equipment Calibration, Maintenance, and Testing
OPS 602— Design of Pressure Regulating Systems
OPS 617—Outside Leak Investigation, Pinpointing, and Grading
OPS 703—Valve Inspection and Maintenance
Forms:
N/A
TRAINING AND QUALIFICATION
Technical Training is responsible for the development of training required for MDUG personnel who
perform regulator station inspection and maintenance.
RECORD RETENTION
Record Retention Period Storage Location
Relief Capacity Check Report Five years Electronic copy in Engineering
Services SharePoint site.
Regulator Station Maintenance Five years Compliance tracking software
Form application. (Maximo)
As-Builts and/or modifications Life of pipe Documentum or similar.
Pipeline Inspection Manager,
Pre-June 22, 2020, Legacy Five years Export on SharePoint, and
Maintenance Records Paper Forms in Local District
Offices or Meter Shops.
Pipeline Company(Foreign
Owned) Controlled Regulator Five years SharePoint
Station Inspection
Documentation
DEFINITIONS
Refer to OPS 3 - Master Glossary
I NT-G-26-08
Attachment F
Page 1 of 14

POLICY STATEMENT OPS 500
Cascade Natural Gas Corporation Regulator Station Inspection and Status: Released
Great Plains Natural Gas Co. Maintenance Revision Date: Oct.28,2024
Intermountain Gas Company OPSMOC-2215&2217
Montana-Dakota Utilities Co. Page 2 of 14
LOCKUP PRESSURE —The point at which a regulator shuts off completely under no-flow conditions.
OPERATING PRESSURE — REGULATOR—Outlet pressure of regulator under flow. For meter set
outlets, sometimes referred to as Delivery Pressure.
SET PRESSURE— RELIEF VALVE—The pressure at which the relief valve (not the pilot) begins to
operate (e.g., crack, seep, open, etc.).
TOWN BORDER STATION (TBS) -A location at which gas may change ownership from one party to
another(e.g., from a transmission company to a local distribution company), neither of which is the
ultimate consumer. Legacy documents and certain facility names may include industry terms such as city
gate, gate station, or tap (e.g., McCleary Gate Line Heater or Nampa Gate).
SCOPE
Applies to the inspection and maintenance of pressure regulating and relief devices within the MDUG
pipeline system feeding three (3) or more service lines (e.g., GIS Gas Service Point).
PROCEDURE
1. GENERAL
1.1. Periodic inspections and tests shall be performed on regulation stations and relief devices,
including standalone relief devices that are essential and/or non-essential for overpressure
protection.
1.2. Inspection and maintenance shall be documented in the compliance tracking software
applications (e.g., Maximo).
1.3. Descriptions of unacceptable conditions shall be entered in the work order comments.
1.4. Gauges used for inspection and maintenance of regulator stations, relief valves, and
bypassing regulator stations shall be calibrated per the requirements of OPS 501 - Equipment
Calibration, Maintenance, and Testing.
1.5. Regulator Stations are assigned an eight(8) digit unique identification (ID) number. The
unique ID is auto generated by the compliance tracking software application (e.g., Maximo).
The unique ID will be preceded with the Company and Town Code.
1.5.1. Company-Town Code-Unique 8-digit ID.
1.5.1.1. Example: 48425-RS-00012345.
1.6. Pressure limiting stations, relief devices, and the associated equipment shall be inspected at
least once each calendar year, with intervals not exceeding 15 months.
1.6.1. Engineering Services, and System Integrity, shall inform Measurement when
inspection and testing frequencies require increased intervals.
1.6.2. Examples of criteria that may require increased inspection and testing frequencies
due to buildup in regulator or meter components include, but are not limited to,
dithiazine, sulfur, and condensates.
1.6.2.1. Inspections performed outside the frequencies of 1.6 not related to
dithiazine, condensates, or sulfur shall be documented on an AdHoc Work
Order.
1.6.2.1.1. Unless maintenance is required (e.g., rebuilds, pressure
adjustments, etc.)AdHoc Work Orders are not required for
state or federal regulatory agency inspections.
1.6.2.2. If dithiazine, condensates, or sulfur is found during an annual or AdHoc
inspection, a follow-up dithiazine job plan inspection shall be conducted
every three (3) months not to exceed four and a half(4 '/2) months.
1.6.2.2.1. Follow-up inspections shall continue every three (3) months
not to exceed four and a half(4 '/2) months until an inspection
is completed without the presence of dithiazine, condensates,
or sulfur.
INT-G-26-08
Attachment F
Page 2 of 14

POLICY STATEMENT OPS 500
Cascade Natural Gas Corporation Regulator Station Inspection and Status: Released
Great Plains Natural Gas Co. Maintenance Revision Date: Oct.28,2024
Intermountain Gas Company OPSMOC-2215&2217
Montana-Dakota Utilities Co. Page 3 of 14
1.7. The lockup and set point pressures for regulators and reliefs shall be determined by
Engineering Services in compliance with §192.201... Required Capacity of Pressure Relieving
and Limiting Devices. The lockup and set point pressure data shall be documented in Maximo.
1.8. The inspections and tests specified in this procedure shall determine that the devices are:
1.8.1. In good mechanical condition and overall appearance.
1.8.2. Set to control or relieve at the correct pressure, consistent with the pressure limits in
Maximo.
1.8.3. Properly installed and protected from insects, dirt, liquids, or other conditions that
might prevent proper operation.
1.9. Exhibit 1 outlines potential inspectable items.
2. START UP
2.1. During the commissioning (e.g., starting up) of new regulator stations, the set pressures of
regulators and relief valves shall be set per the requirements of OPS 602— Design of
Pressure Regulating Systems.
2.2. When a regulator station is utilized to shut in (e.g., isolate) a section of pipeline, the
overpressure protection devices shall be checked for proper operation per the requirements of
this procedure during start up to ensure the maximum allowable operating pressure (MAOP) is
not exceeded.
2.3. When a regulator station is utilized to reduce pipeline pressure during maintenance, the
overpressure protection devices shall be checked for proper operation, per the requirements
of this procedure, when the pressure is returned to normal operating pressure to ensure
MAOP is not exceeded.
2.4. Check for station signage.
2.4.1. If signage is missing and not installed during the commissioning, a Work Order shall
be created in Maximo to have signage installed (e.g., deficiency or AdHoc).
3. GENERAL INSPECTION AND MAINTENANCE
3.1. Prior to performing regulator maintenance, notify Gas Control if the regulator station is
monitored by SCADA.
3.2. The following steps shall be taken prior to regulator inspections and/or maintenance to ensure
safe operating conditions:
3.2.1. Verify in GIS what the station outlet is feeding/serving and if the station is fed from
other regulator stations (e.g., loop fed, back fed, etc.).
3.2.2. Utilize approved gas monitoring equipment while performing regulator station
inspections and/or maintenance.
3.2.3. Utilize two (2) employees while performing maintenance on regulators/reliefs six
inches (6") and larger, unless otherwise approved by management. An example of an
exception is an onsite lifting device/hoist for the removal of heavy regulator and relief
components. Additional employees may be needed when bypassing a station.
3.3. Inspect for leaks.
3.3.1. If qualified, repair the leak.
3.3.2. If not qualified or additional personnel is required, refer to qualified personnel to
grade the leak and schedule repair. Refer to OPS 617 - Outside Leak Investigation,
Pinpointing, and Grading.
3.3.3. Non-hazardous above ground leaks that can be repaired by tightening component(s)
without disassembly and non-hazardous leaks on valves that can be repaired with
grease (e.g., injecting lubricant or sealant)do not need to be reported. Other leak
types require an order to be generated for tracking and permanent record.
3.4. Inspect site conditions.
3.5. Inspect pit or vault condition.
3.6. Inspect soil-to-air interface.
3.7. Inspect for Atmospheric Corrosion.
3.7.1. Pipe in "Poor" condition (e.g., severe corrosion) shall be identified as an AOC.
I NT-G-26-08
Attachment F
Page 3 of 14

POLICY STATEMENT OPS 500
Cascade Natural Gas Corporation Regulator Station Inspection and Status: Released
Great Plains Natural Gas Co. Maintenance Revision Date: Oct.28,2024
Intermountain Gas Company OPSMOC-2215&2217
Montana-Dakota Utilities Co. Page 4 of 14
3.8. Inspect pipe supports to ensure all pipe is insulated away from all pipe supports.
3.8.1. If pipe has epoxy coating or other System Integrity approved product at the interface
with the support, the support does not need to be lowered to inspect for corrosion at
the interface.
3.9. For regulator stations enclosed in a building, inspect pipe to ensure it is not in contact with the
building, eliminating risk of electrical shorts, and hazards.
3.10. Inspect barricades, including the condition of existing barricades, or the need to add additional
barricades to protect the facility. Refer to OPS 313—Gas Facility Protection.
3.11. Inspect paint condition.
3.12. Inspect station signage.
3.13. Inspect pipeline markers.
3.13.1. Inspection includes the condition of existing pipeline marker, or the need to add a
pipeline marker(s)at a road crossing, or for better visibility of the regulator station.
3.14. Inspect condition of relief stack.
3.15. Check the position and operation of the relief cap indicator flag, weather cap, or flapper.
3.15.1. Remove weather caps to ensure they are not adhered to the relief stack.
3.15.2. Lubricate or replace inoperable flappers.
3.15.3. Replace missing weather caps.
3.15.4. Replace missing or damaged vent splash guards.
3.16. Inspect and maintain valves that are part of the regulator station per the inspection and
maintenance criteria of OPS 703—Valve Inspection and Maintenance.
3.16.1. Inlet and outlet valves assigned a Maximo ID are included in a separate valve
maintenance program and documented on a Valve Annual Maintenance Work Order
in the compliance tracking software application. Refer to OPS 703—Valve Inspection
and Maintenance.
3.17. Calibrate or check the accuracy of non-transmitting (e.g., no modem) pressure recording
device installed at regulator stations supplied by more than one pressure reducing station.
3.17.1. Pressure recording devices equipped with transmitting devices (e.g., modems) are
included in a separate calibration/maintenance program.
3.17.2. Instruments that are damaged or fail to calibrate will be taken out of service.
3.18. Calibrate or check the accuracy of permanently installed gauges. NOTE: Gauges not used for
accuracy and used as "Indication Only" gauges shall be stickered or labeled as being an
"Indication Only" gauge.
3.18.1. Instruments that are damaged or fail to calibrate will be taken out of service.
3.19. Check pilot heaters for proper operation.
3.19.1. Inoperable pilot heaters shall be repaired or replaced.
3.20. Check inlet pressure with a test gauge rated higher than the MAOP.
3.21. Install a test gauge on the outlet side of the regulator station and monitor the outlet pressure
throughout the regulator and relief valve inspection and maintenance process. Test gauges
shall be rated for pressure that is higher than the MAOP.
4. REGULATOR INSPECTION AND MAINTENANCE
4.1. Regulators shall be set to lockup at the designated lockup pressure, with some allowance for
lockup fluctuation (see chart below), but the regulator shall lockup at a pressure equal to or
less than the MAOP.
I NT-G-26-08
Attachment F
Page 4 of 14

POLICY STATEMENT OPS 500
Cascade Natural Gas Corporation Regulator Station Inspection and Status: Released
Great Plains Natural Gas Co. Maintenance Revision Date: Oct.28,2024
Intermountain Gas Company OPSMOC-2215&2217
Montana-Dakota Utilities Co. Page 5 of 14
Lockup Specified Pressure Lockup Fluctuation Allowance +/-
Low Pressure
Up to 14 in/w.c. 1.5 in/w.c.
15-28 in/w.c. 2.0 in/w.c.
Distribution
2-4 psig 0.5 psig
5-10 psig 1.0 psig
11-60 psig 2.0 psig
High Pressure and Transmission
61-125 psig 3.0 psig
126-250 psig 5.0 si
251-500 psig 8.0 si
501+ psig 10.0 psig
*Contact Engineering Services if lockup pressure is left outside the lockup fluctuation
allowance.
4.2. Note: Manufacturers droop capacities are typically for long lengths of pipeline, not the short
spans (e.g., distance between the regulator and outlet valve) used for lockup testing.
4.2.1. When a regulator run is not equipped with the pressure ports required for lockup
testing, the set pressure shall be no greater than MAOP less the manufacturer's
droop capacity.
4.3. Regulator stations that are not equipped with pressure ports to test lockup shall be inspected
per the requirements of Section 1.8.
4.4. Confirm regulator vents are vented down.
4.5. Switching primary (e.g., operating) and secondary(e.g., standby) regulators is allowed but not
required.
4.5.1. When delivery pressure cannot be reduced, the secondary run shall be raised to the
delivery pressure and can be made the primary regulator after maintenance is
complete.
4.5.2. When primary and secondary regulators are switched, the lockup pressure labels
shall be updated.
4.5.3. When the primary and secondary regulator are a different manufacturer or model, do
not switch the runs.
4.6. Switching current secondary regulator to the primary regulator:
4.6.1. Begin by installing the test tree on the secondary run.
4.6.2. Open bleed valve on tree to protect the gauge if regulator fails to lockup. Slowly close
the downstream outlet valve on the secondary regulator run; and watch the
monitoring gauge on the bypass line to verify that there is no reduction in system
pressure. Close the bleed valve on the test tree so the gauge can indicate the lockup
of the regulator.
4.6.3. Note: If the primary regulator does not provide proper pressure or is a single run
regulator station, the station may need to be bypassed during the regulator
maintenance. Refer to Section 7 for bypass procedures.
4.6.4. Turn the adjustment screw on the regulator and bring the secondary pressure up to
the primary lockup pressure as specified in Maximo. Never set a regulator to lockup
above MAOP.
4.6.5. If the regulator fails to lockup, disassemble the regulator and pilot (if applicable),
clean, and/or repair, and retest for lockup.
4.6.6. Fully open the bleed valve on the test tree and verify that the regulator will flow. Then
close the bleed valve to verify that the regulator locks up at the proper set pressure.
4.6.7. If regulator run has a monitor regulator, repeat Steps 4.6.2 through 4.6.6 for monitor
regulator. Set monitor to lockup pressure as specified by Engineering Services. If
I NT-G-26-08
Attachment F
Page 5 of 14

POLICY STATEMENT OPS 500
Cascade Natural Gas Corporation Regulator Station Inspection and Status: Released
Great Plains Natural Gas Co. Maintenance Revision Date: Oct.28,2024
Intermountain Gas Company OPSMOC-2215&2217
Montana-Dakota Utilities Co. Page 6 of 14
regulator run is a "working monitor," verify the first stage pilot controls the monitor
regulator at the lockup pressure designated by Engineering Services. Ensure second
stage pilot locks up the monitor regulator at pressure specified by Engineering
Services. Ensure primary worker regulator is aligned and controlling pressure for the
regulating run prior to moving to the next step.
4.6.8. Slowly open the downstream regulator outlet valve, making the secondary regulator
the new primary regulator.
4.7. Switching current primary regulator to secondary regulator:
4.7.1. Install the test tree on the opposite regulator run. This regulator will now be set as the
secondary regulator.
4.7.2. Open the test tree bleed valve to protect the gauge if the regulator does not lockup.
Close the downstream block valve and watch the monitoring gauge on the bypass
line to verify that there is no drop in system pressure. Close the bleed valve on the
test tree so the gauge can indicate the lockup of the regulator.
4.7.3. Open the bleed valve slightly on the test tree to relieve pressure between the
regulator and the downstream valve and turn the adjustment screw on the regulator
to bring the pressure to the secondary pressure setting.
4.7.4. Close the needle valve on the test tree and adjust the regulator to the proper lockup
pressure for the secondary regulator. If the regulator fails to lockup, disassemble the
regulator and pilot (if applicable), clean and/or repair, and retest for lockup.
4.7.5. Fully open the bleed valve on the test tree to verify that the regulator will flow. Then
close the bleed valve to verify that the regulator locks up at the proper set pressure.
4.7.6. If regulator run has a monitor regulator, repeat Steps 4.7.2 through 4.7.5 for monitor
regulator. Set monitor to lockup pressure as specified in Maximo. If regulator run is a
"working monitor," verify first stage pilot controls monitor regulator at lockup pressure,
then ensure second stage pilot locks up monitor regulator. Ensure primary worker
regulator is aligned and controlling pressure for the regulating run prior to moving to
the next step.
4.7.7. Slowly open the downstream block valve and put the secondary regulator into
service.
5. RELIEF VALVE INSPECTION AND MAINTENANCE
5.1. Relief valve capacities shall be reviewed at least once each calendar year, with intervals not
exceeding 15 months, by review of calculations.
5.1.1. Engineering Services is responsible for the review of the relief valve capacities using
calculations.
5.1.2. Engineering Services shall document the annual review of the relief capacity check
on the Engineering Services SharePoint site.
5.1.3. If the capacity of the relief is not sufficient, Engineering Services shall notify the
appropriate department and assist with solution to the relief capacity issue.
5.2. When shutting in relief valves during inspection, testing, or maintenance, the outlet system
pressure shall be monitored to ensure the pressure does not exceed MAOP. If the gauge
monitoring the outlet/delivery pressure cannot be seen while the relief valve is shut in, install a
gauge on the inlet side of the relief block valve or ask for additional personnel to assist with
pressure monitoring.
5.3. Install a test tree with a test gauge on a pressure tap between the relief valve and the relief
isolation valve.
5.4. Slowly close the relief isolation valve to the relief assembly. Constantly monitor the
outlet/delivery pressure for any pressure change.
5.5. Install a high-pressure gas hose rated to the MAOP of the inlet pressure on the test tree to test
the relief.
5.5.1. The hose may be supplied with upstream gas or compressed gas cylinder(e.g.,
nitrogen or compressed natural gas).
INT-G-26-08
Attachment F
Page 6 of 14

POLICY STATEMENT OPS 500
Cascade Natural Gas Corporation Regulator Station Inspection and Status: Released
Great Plains Natural Gas Co. Maintenance Revision Date: Oct.28,2024
Intermountain Gas Company OPSMOC-2215&2217
Montana-Dakota Utilities Co. Page 7 of 14
5.5.2. Relief valves shall not be tested by increasing the system pressure through the
regulator station.
5.6. Open the test fitting valve and allow high-pressure gas to open the relief valve. Verify that the
main seat of the relief valve opens.
5.7. Close the test fitting valve.
5.8. Slowly open the valve from the high-pressure hose while watching the test gauge on the test
tree.
5.9. As the pressure slowly increases on the test gauge, the set pressure for the relief valve is the
highest pressure reached until it stops, and main body has cracked open.
5.9.1. Note: The relief valve will be heard when it's cracked open and beginning to vent. At
this point, a pressure drop may be seen on the test gauge once the highest pressure
is achieved, and the relief valve has opened.
5.10. When the set point is found higher than the set point designated in Maximo, adjust the relief
valve to the correct set point.
5.11. Turn off the high-pressure supply and watch the gauge on the test tree to verify that the relief
valve re-seats and does not fall below the upstream regulator's lockup pressure. This is
typically referred to as a relief valve leak test or relief valve re-seat.
5.12. Open the bleed on the test tree to relieve pressure from tree and high-pressure hose.
5.13. Place the relief valve back in service by closing the bleed on the test tree and slowly opening
the relief isolation valve to the fully open position, supplying gas to the relief valve.
5.13.1. With the relief valve in operation, verify the outlet/delivery pressure at the test tree
matches the outlet/delivery pressure at the monitoring point described in Section
3.19.
5.14. Remove the test tree and high-pressure hose and record the station inlet pressure.
6. POST INSPECTION AND MAINTENANCE
6.1. Check that valves are left in the correct position.
6.2. Check that relief valves are locked open.
6.3. Check that bypass valves are locked closed.
6.4. Check that fence gate is locked.
6.5. Install labels (replace old labels if necessary) that identify the regulator pressure setpoints on
the primary and secondary runs and the set pressure on the relief, using stickers or tags (e.g.,
Impresso tags, brass tags, etc.).
6.5.1. Permanently installed analogue gauges shall be labeled "Indication Only."
6.6. Required corrective maintenance (e.g., deficiencies) not repaired at the time of inspection
shall be completed no later than the following time frames:
6.6.1. Inoperable regulators and relief valves shall not be left in service and shall be
repaired or replaced as soon as possible. Regulator stations shall not be left in
service without over pressure protection. When a regulator run or regulator station
must remain out of service due to the unavailability of replacement parts, the
employee performing the inspection or maintenance shall contact their supervisor, or
manager, and Engineering Services.
I NT-G-26-08
Attachment F
Page 7 of 14

POLICY STATEMENT OPS 500
Cascade Natural Gas Corporation Regulator Station Inspection and Status: Released
Great Plains Natural Gas Co. Maintenance Revision Date: Oct.28,2024
Intermountain Gas Company OPSMOC-2215&2217
Montana-Dakota Utilities Co. Page 8 of 14
General Inspection and Maintenance Deficiencies Days
Grade 1 Leak Promptly with continuous action
Grade 2 Leak Repaired - No 180
Grade 3 Leak Repaired - No 15 months
Site Condition Unacceptable 180
Vault/Pit Condition Unacceptable 365
Vault/Pit Condition Unacceptable—AOC 10
Soil-to-Air Interface Condition Unacceptable 180
Atmospheric Corrosion Found 180
Pipe Support Unacceptable 180
Paint Condition Unacceptable 1095
Signage Unacceptable 90
Pipeline Markers Unacceptable-Washington 45
Pipeline Markers Unacceptable 365
Relief Vent or Stack Condition Unacceptable 45
Weather Cap Missing/Flapper Not Operable 45
Valve Condition Unacceptable 180
Pressure Recording Device Unacceptable Take out of service or replace
Permanently Mounted Pressure Gauge Unacceptable Take out of service or replace
Pilot Heater Inoperable 45
Regulator and Relief Deficiencies Days
Regulator Vent Not Vented Downward 45
Regulator 1 Lockup Performed Properly—No 45
Regulator 1 Operated Properly—No 45
Regulator 2 Lockup Performed Properly—No 45
Regulator 2 Operated Properly—No 45
Regulator 3 Lockup Performed Properly—No 45
Regulator 3 Operated Properly—No 45
Regulator 4 Lockup Performed Properly—No 45
Regulator 4 Operated Properly—No 45
Relief Operated Properly—No 45
Relief Isolation Valve Locked Open—No 45
Relief 2 Operated Properly—No 45
Relief 2 Isolation Valve Locked Open— No 45
Valves Left in Proper Position— No 45
Regulator 1 Rebuilt-Yes
Regulator 2 Rebuilt—Yes (If YES to all, reset 10-year clock)
Relief Valve Rebuilt-Yes
I NT-G-26-08
Attachment F
Page 8 of 14

POLICY STATEMENT OPS 500
Cascade Natural Gas Corporation Regulator Station Inspection and Status: Released
Great Plains Natural Gas Co. Maintenance Revision Date: Oct.28,2024
Intermountain Gas Company OPSMOC-2215&2217
Montana-Dakota Utilities Co. Page 9 of 14
Post Inspection and Maintenance Deficiencies Days
Valves Left in Proper Position—No 1
Relief Isolation Valves Locked Open—No 45
Bypass Valves Locked Closed - No 45
Fence Gate Locked - No 1
7. BYPASSING REGULATOR STATION
7.1. Prior to bypassing a regulator station, notify Gas Control if the regulator station is monitored
by SCADA.
7.2. Unless performed during normal maintenance, bypassing regulator stations shall be done at
the direction of Field Operations Management and/or Engineering Services.
7.2.1. If the above departments are unable to be reached, contact Gas Measurement.
7.3. Contact Engineering Services if assistance is needed with planned bypasses involving
pressure differentials. Bypasses involving the same pressure do not require Engineering
review.
7.4. Bypassing shall be performed with a second employee designated to monitor
downstream/delivery pressure unless the downstream/delivery pressure can be continually
visually monitored while the system is on bypass.
7.5. Prior to bypassing, conduct a job safety assessment, or tailgate, to review the work plan.
7.6. When bypassing a regulator station, the following procedure shall be followed:
7.6.1. Verify relief isolation valve is open and operational.
7.6.2. Monitor the downstream pressure. The gauge shall be installed at a test point where
it can be clearly observed.
7.6.3. When bypassing due to significantly low system pressure, verify that the end of the
system has adequate pressure to maintain service prior to increasing the existing
outlet pressure. Contact Engineering Services if assistance is needed identifying a
significantly low pressure.
7.6.3.1. When SCADA or other monitored pressure device is not available, the
pressure shall be verified with a pressure gauge at the end of the system.
7.6.3.2. Customers in outlying areas of the distribution system may have lost
service. Their service condition will need to be verified and shut off, if
necessary, along with Engineering Services approval before the distribution
pressure could be increased to a normal operating pressure.
7.6.4. When bypassing into a high-pressure system use a gauge that is capable of reading
from zero (0)to the highest pressure possible in the system. The gauge shall be
installed on a test point where it can be clearly observed while operating the bypass
valve.
7.6.5. When bypass runs are equipped with two (2) ball valves (a bypass valve and a
control valve), use the sacrificial bypass valve for bypassing. The upstream valve is
typically designated as the bypass valve and the downstream valve is designated as
the control valve. Always open the control valve prior to bypassing.
7.6.6. Open bypass valve with an adequately sized unidirectional wrench. If the valve does
not turn easily refer to OPS 703—Valve Inspection and Maintenance.
7.6.7. Open the valve gradually to let pressure seep by the valve. During the bypass
process, the pressure on the gauge shall be monitored continuously. Observe the
pressure and control it by throttling. The valve shall not be left unattended during the
bypass operation. The system pressure shall not be allowed to go over system's
designed delivery pressure.
7.6.8. When bypassing is no longer necessary, close the bypass valve and reinstall the
locking device.
I NT-G-26-08
Attachment F
Page 9 of 14

POLICY STATEMENT OPS 500
Cascade Natural Gas Corporation Regulator Station Inspection and Status: Released
Great Plains Natural Gas Co. Maintenance Revision Date: Oct.28,2024
Intermountain Gas Company OPSMOC-2215&2217
Montana-Dakota Utilities Co. Page 10 of 14
7.6.9. The system pressure shall be observed to make sure the regulator station is working
correctly and is able to keep up with the current system demand. Monitoring for less
than 30 minutes requires Engineering Services, or System Integrity, authorization.
7.6.10. Remove pressure gauge and confirm the bypass valve is closed and locked off.
8. BLOWING OR RELIEVING (SEEPING) RELIEF VALVE
8.1. First responders that are not operator qualified to perform regulator and relief valve inspection
and maintenance shall notify their Supervisor On-Call as soon as reasonably possible.
Supervisor shall follow local protocol for contacting a Meter Inspector.
8.2. Unqualified personnel shall perform the following steps:
8.2.1. Establish a safety perimeter.
8.2.2. Install gauges on the upstream and downstream of the regulator station.
8.2.3. Relay the upstream and downstream pressures to the Supervisor On-Call, or
Measurement.
8.2.4. Continue to monitor pressure until qualified personnel arrive.
8.2.5. Remain on site to assist until relieved by a qualified individual.
8.3. Qualified personnel shall perform the following steps:
8.3.1. Install a pressure gauge rated for the inlet MAOP on the downstream side of the
bypass valve and read the pressure.
8.3.2. Note the pressures on the regulator labels (the label on the relief valve).
8.3.3. A downstream pressure that is higher than the station's set pressure indicates that
the bypass valve (if present) has been turned to the open position or one of the
regulators has failed.
8.3.4. If the bypass valve has been opened, close it immediately. This shall allow the
pressure to return to normal and the relief valve to stop blowing.
8.3.5. To determine if the problem is caused by a failed regulator, complete the following:
8.3.5.1. Slowly close the inlet valve on the primary regulator and watch the gauge
installed on the downstream side of the bypass valve.
8.3.5.2. If the pressure drops down to normal and the relief valve closes, you have
found the problem. With the inlet valve on the regulator run in the off
position, watch the gauge, and make certain the bypass valve does not
need to be opened to maintain pressure on the system.
8.3.5.3. After closing the inlet valve to the primary regulator, if the pressure on the
gauge remains high and the relief valve still blows, turn the inlet valve back
on, and follow the same procedure on the secondary regulator. If either
regulator does not lockup, it requires immediate repair.
8.3.6. If the gauge pressure is less than the system set pressure, slowly close the relief
isolation valve, and watch the system gauge. If the pressure on the gauge rises to
the relief set point pressure, open the relief isolation valve. This would indicate a
failed regulator or open bypass valve.
8.3.7. If the pressure on the gauge stabilizes to a proper setting after turning off the relief
isolation valve, the relief valve shall be repaired.
8.3.8. Do not leave an inlet or outlet regulator run valve or relief isolation valve in the closed
position without Engineering Services approval. When an inlet or outlet regulator run
valve or relief isolation valve must be left in the closed position, the employee
performing the inspection or maintenance shall contact their supervisor, or manager.
8.3.9. Inlet and outlet regulator run valves and relief isolation valves shall not be operated
unless the outlet/delivery pressure is being monitored.
8.3.10. Remain at the station and monitor pressures until repairs are made and pressures
are normal.
8.3.11. If the problem cannot be resolved after following the above steps, contact a
supervisor, or manager, to request additional assistance.
I NT-G-26-08
Attachment F
Page 10 of 14

POLICY STATEMENT OPS 500
Cascade Natural Gas Corporation Regulator Station Inspection and Status: Released
Great Plains Natural Gas Co. Maintenance Revision Date: Oct.28,2024
Intermountain Gas Company OPSMOC-2215&2217
Montana-Dakota Utilities Co. Page 11 of 14
8.3.12. Verify that valves on the station are in their proper position and that the locking
devices are installed and secured on both the bypass valve and the relief isolation
valve.
8.3.13. Inoperable regulators and relief valves shall not be left in service and shall be
repaired or replaced as soon as possible. Regulator stations shall not be left in
service without over pressure protection. When a regulator run or regulator station
must remain out of service due to the unavailability of replacement parts, the
employee performing the inspection or maintenance shall contact their supervisor, or
manager, and Engineering Services.
9. PIPELINE COMPANY (FOREIGN OWNED) CONTROLLED REGULATOR STATIONS
9.1. The following interstate pipeline companies may provide pressure control and over-pressure
protection for MDUG facilities at TBS:
9.1.1. Northwest Pipeline (NWP), a subsidiary of the Williams Companies.
9.1.2. Gas Transmission Northwest (GTN), a subsidiary of TransCanada Corporation.
9.1.3. NorthWestern Corporation, d/b/a NorthWestern Energy (NWE).
9.1.4. WBI Energy, an MDU Resources Group company.
9.2. The pipeline companies are responsible for inspecting these TBS at least once each calendar
year, with intervals not exceeding 15 months.
9.2.1. It is the responsibility of Engineering Services to obtain the inspection documentation
from the pipeline within the required interval. These inspection records shall be
stored on SharePoint.
9.2.2. It is the responsibility of Engineering Services to ensure the regulator and relief set
points are within acceptable ranges.
I NT-G-26-08
Attachment F
Page 11 of 14

POLICY STATEMENT OPS 500
Cascade Natural Gas Corporation Regulator Station Inspection and Status: Released
Great Plains Natural Gas Co. Maintenance Revision Date: Oct.28,2024
Intermountain Gas Company OPSMOC-2215&2217
Montana-Dakota Utilities Co. Page 12 of 14
EXHIBIT 1 -
Quality Inspection Protocol Checklist
OPS 500 Related
Section Acceptance Criteria for Conforming Work Quality
Protocol
3.2 a) Prior to performing regulator maintenance, gas detecting equipment is used to QIP 102
check for the presence of natural gas. QIP 103
3 2 2 a) Calibrated gas monitoring equipment is used while performing regulator station QIP 185
inspection.
a) Relief stack flapper is operated to the fully open and closed position OR
lubricated OR replaced if inoperable.
3.14 b) Relief cap indicator flag is operated to the fully open and closed position. QIP 185
c)Weather caps are removed and reinstalled.
d Weather caps and/or vents lash guards are present OR replaced if missing.
Are permanently installed gauges present?
•Yes= inspect, No= proceed to next step
3.16 a) Permanently installed gauges are calibrated OR checked for accuracy. QIP 185
b) Gauges that are damaged or fail to calibrate are removed from service.
c)Gauges not used for accuracy, and used as indication only gauges, are labeled
as"Indication Only."
3.18 c Inlet pressure is checked with a gauge rated higher than MAOP. QIP 185
3.19 d Outlet pressure is checked with a gauge rated higher than MAOP. QIP 185
3.20 a) Pressure gauge is installed on the outlet side of pressure regulation. QIP 102
b Pressure gauge is rated fora pressure higher than MAOP. QIP 103
4.1 a) Regulator is adjusted or verified to operate at a specified set point. QIP 102
c Lock-up pressure does not exceed MAOP.
4.6.5 b) If desired pressures cannot be achieved, regulator is repaired or removed from QIP 102
service.
Was the regulator adjusted?
4.6.5 Yes = Inspect, No = Proceed to next step QIP 102
a After initial adjustment, regulator operation during flow and lockup is reverified.
4.7.7 a Block valves are operated slowly. QIP 102
5.2 b) Station pressure does not exceed MAOP. QIP 102
QIP 103
5.4 a) Station pressure is monitored during the inspection process. QIP 102
QIP 103
a)An MAOP rated high pressure hose is used to supply pressure to the test tree.
5.5 b)Testing pressure is supplied by upstream pressure or compressed gas. QIP 103
c Testing pressure is not supplied by increasing regulator station pressure.
5.9, 5.10 a Relief valve is adjusted or verified tooperate at a specified set point. QIP 103
5.11 c After set point is adjusted or verified, relief valve is leak tested. QIP 103
a) Relief valve isolation valve is operated slowly.
5.13 b) Relief valve isolation valve is closed during testing of the relief valve. QIP 103
c) Relief valve isolation valve is placed in the proper position when maintenance is
complete.
5.13.1 a)With the relief valve in service, test tree outlet pressure matches the station QIP 103
outlet pressure.
6.1 b Block valves are placed in the proper position when maintenance is complete. QIP 102
6.6.1 b) If desired pressures cannot be achieved, relief valve is repaired, or removed, QIP 103
from service.
I NT-G-26-08
Attachment F
Page 12 of 14

POLICY STATEMENT OPS 500
Cascade Natural Gas Corporation Regulator Station Inspection and Status: Released
Great Plains Natural Gas Co. Maintenance Revision Date: Oct.28,2024
Intermountain Gas Company OPSMOC-2215&2217
Montana-Dakota Utilities Co. Page 13 of 14
ADMINISTRATION
The Vice President, Engineering &Operations Services of the MDU Utilities Group is responsible for
establishing this policy. Administration of this policy is the responsibility of the Director, Policy&
Procedures.
erluA4NNimK.m Q �.�i��arra
Reviewed: AAN�E��.,,,_�,,,:,��. Approved: ki — GDirector, Policy& Procedures Vice Presldtf,�•`-
Engineering &Operations Services
Date: 8-5-21 Date: 8-5-21
REVISIONS
Major Revision Summary MOC# Date
Original procedure as part of O&M manual integration. Supersedes
CNGC CP 745, IGC 4306 and MDU GDS Sec 9, pg. 134. OPSMOC-359 4/13/2020
Added Section 2. Start Up, Revised Section 3.3.1 (4.3.1 with addition OPSMOC-742
of Section 2)eliminating the need for Measurement personnel to OPSMOC-770 12/15/2020
contact ES. & Removed Section 1.2.1. OPSMOC-791
Removed the rebuild section (previously section 9) and the 10-year
rebuild requirement. Added 6.5.1. regarding "Indication Only"for OPSMOC-1080 6/16/2021
permanently installed analogue gauges.
Updated inspection frequency when dithiazine/sulfur is found in a OPSMOC-884 8/24/2021
regulator.
Minor Revision Summary MOC# Date
Revised 9.2.1. Specifying the storage location of inspection records. NA 7/27/2020
Changed Vault/Pit Condition Deficiency from 45 days to 365 days. 10/12/2021
Added Vault/Pit Condition Deficiency—AOC. OPSMOC-1149
Section 6: Added remediation time frame for grade 2 and 3 leaks in
deficiency table, minor language updates through deficiency table to OPSMOC-1167 2/2/2022
align with other OPS procedures. Update signage from 45 to 90
days.
Revise 4.1. to Regulators shall be set to lockup at the designated
lockup pressure, with some allowance for lockup fluctuation (see OPSMOC-1102 6/8/2023
chart below), but the regulator must lockup at a pressure equal to or
less than the MAOP.
Added 3.7.1. and 7.2.1., Revised 7.6.2. adding language for the OPSMOC-1752 7/19/2023
placement of gauge when a pressure recorder is present.
INT-G-26-08
Attachment F
Page 13 of 14

POLICY STATEMENT OPS 500
Cascade Natural Gas Corporation Regulator Station Inspection and Status: Released
Great Plains Natural Gas Co. Maintenance Revision Date: Oct.28,2024
Intermountain Gas Company OPSMOC-2215&2217
Montana-Dakota Utilities Co. Page 14 of 14
Language has been added to clarify ES completing the annual OPSMOC-1615 & 10/27/2023
reviews of the regulator stations and more clearly document the OPSMOC-1492
reviews.
Add 'condensates' as an item that would require inspection
frequency increase if found to sub-steps of 1.6. Addition of section OPSMOC-1496 & 1/8/2024
2.4. Check for signage. Revised the following sections to state OPSMOC-1920
lockup pressure: 4.5.2., 4.6.7. 4.7.6. Revised section 4.6.4. & 5.9.
Removed section 4.3.1.
2024 Annual Review: Added section 1.9., 3.9., & 3.10. Revised
section 3.8. & pipeline markers unacceptable to 365 days in general OPSMOC-2215 & 10/28/2024
inspection and maintenance deficiencies table. Removed section OPSMOC-2217
4.5.4.
I NT-G-26-08
Attachment F
Page 14 of 14