I202408 NOPV Response

EXECUTIVE OFFICES
INTERMOUNTAIN GAS COMPANY
555 SOUTH COLE ROAD-P.O.BOX 7608• BOISE,IDAHO 83707• [phone]• FAX:[phone]
September 25,2024
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 August 15,2024(Report#I202408)
Dear Mr.Brooks,
This letter is intended to address five(5)notice of probable violations stemming from a failure investigation and site
follow-up conducted by the Idaho Public Utilities Commission(IPUC)on July 17,2024,on incident
NRC#1404942/1405150 of Intermountain Gas Company(IGC)pursuant of Chapter 601 Title,49,United States
Code.
PROBABLE VIOLATIONS
1. 49 CFR§ 19302503
Each operator shall follow one or more manuals of written procedures to provide safety in normal operation
and in responding to an abnormal operation that would affect safety.
The procedures must include provisions for:
(b)Startup and shutdown,including for initial startup,performance testing to demonstrate that components
will operate satisfactory in service.
49 CFR§ 193,2513 Transfer Procedures
Each transfer of LNG(Liquified Natural Gas)or other hazardous fluid must be conducted in accordance
with one or more manuals of written procedures to provide for safe transfers.+
(bb,)The transfer procedures must include provisions for personnel to:
(1) Before transfer,verify that the transfer system is ready for use,with connections and
controls in proper positions,including if the system could contain a combustible mixture,
verifying that it has been adequately purged in accordance with a procedure which meets
the requirements of"Purging Principles and Practices(incorporated by reference,see
&193.2013)";
(cc,)In addition to the requirements of paragraph(b)of this section,the procedures for cargo transfer must
be located at the transfer area and include provisions for personnel to:
IGC-Rexburg LNG Transfer Operations Procedure 4565
1. GENERAL
1.2. Personnel involved in LNG transfer operations must be familiar and knowledgeable with the transfer
equipment and systems including:
1.1.1. Truck Off-Loading Skid
1.1.2. Piping Systems
1.1.3. Storage Tank
1.1.4. Pump Trailer
1.1.5. Vaporizer
1.1.6. Controls System
2. SAFETY PRCAUTIONS
2.1. Personnel must wear protective clothing.
3. VAPORIZATION TECHNICIAN RESPONSIBILITES
3.3. The Vap. Tech(Vaporization Technician)shall perform the following upon arrival of the LNG
trailer:
3.3.1. Procedure 4565—Rexburg LNG Transfer Operations shall be located at the Truck
Offloading Skid.
3.3.2. Visually check LNG trailers for leaks or other signs of hazardous conditions before making
any connections.

EXECUTIVE OFFICES
INTERMOUNTAIN GAS COMPANY
555 SOUTH COLE ROAD-P.O.BOX 7608• BOISE,IDAHO 83707•[phone]•FAX:[phone]
3.3.13. Verify LNG trailer vent valve and fill valve are closed before connecting/disconnecting
hoses.
3.3.14. Complete necessary items on Rexburg LNG Truck Off Loading Operations Checklist prior
to beginning transfer operations.
3.4. The Carrier/driver is responsible to perform the following and provide the requested information to
the Vap.Tech prior to beginning transfer operations:
3.4.4. Connecting the fill hose and vapor return hose to the LNG trailer.
4. PROCEDURE
4.6. Carrier/driver shall inspect valves,valve box,and pressure build coil on trailer to ensure all
components are damage free and in the proper position for operation.
4.7. Carrier/driver shall begin pressure building in trailer with a target of 60 psig.
4.8. Connect liquid and vapor hoses to the proper LNG trailer connections.
Vap.Tech did not verify valves were in the proper position for operations.
Carrier/driver did not verify valves were in the proper position for operations.
Vap.Tech did not accurately compplete items on Rexburg LNG Truck Off Loading Operations Checklist prior
to beginning transfer operations.(I'icture(s)of checklist upon request).
Rexburgg LNG Truck OOff Loading Operations Checklist dated 7/16/24 is checked that(Tasks)#1,
#3 and 98 were completed prior to startup.
(#1)The transfer system was not verified that it was safe to conduct transfer operations.
(#3)Carrier/driver and LNG Plant Operator did not visually check LNG truck and trailer for safety
viollations and hazardous conditions.
(#8)Valve(V-6)fill line bleed/vent valve on LNG trailer(83110149)was not verified that it was closed
before connecting/disconnecting hoses.
Vap:Techs were unfamiliar and did not know the locations of ESV(Emergency Shutdown Valves)(per
carrier/driver)on trailer,prior to the LNG spill incident.
Vap.Tech at the off-loading skid stated the Procedure 4565 was not located/present for cargo transfer.
Vap.Tech did not visually check LNG trailers for leaks or other signs of hazardous conditions(V-6 fill line
bleed/vent valve left open)before making any connections.\
Carrier/driver did not inspect valves,valve box,and pressure build coil on trailer to ensure all components
are damage free and in the proper position for operation.
Carrier/driver stated that once the truck&trailer were on the off-load skid.The Vap.Tech ensured
brakes were set and trailer wheels were chocked,truck engine was off,keys removed from cab,and
verified that carrier/driver's current state/federal truck and trailer inspection documentation was
checked.Carrier/driver was then informed that he needed to go to the control room and wait till
off-load was completed.
Vap.Tech did not ensure that Carrier/driver performed the following task(s)and provide the requested
information to Vap.Tech prior to beginning transfer operation:
Carrier/driver shall connect liquid and vapor hoses to the proper LNG trailer connections.
Vap.Tech stated that he connected hoses to the LNG trailer.
Carrier/driver shall begin pressure building in trailer with a target of 60 psig.
Vap.Tech performed pressure building and stated to IPUC personnel that the desired
range was between 60-65 PSI to overcome tank head pressure.
During the pressure building is when LNG started venting out of the truck relief
valves.
Intermountain Gas Response
IGC acknowledges the findings brought forth by the IPUC. The Vaporization Technicians received additional
training on the LNG trailer from Kenan Advantage Group (KAG) on August 14, 2024, and August 28, 2024
(see Exhibit A). Training included the following:
• General safety overview of the trailer.
• An overview of the trailer's operation.

EXECUTIVE OFFICES
INTERMOUNTAIN GAS COMPANY
555 SOUTH COLE ROAD-P.O.BOX 7608• BOISE,IDAHO 83707•[phone]• FAX:[phone]
• Emergency Shut Down(ESD)function,testing, and locations.
• Valve orientation for travel, loading,unloading,and each valve function.
• Vent and relief functions and operations.
• Hose hookup and transfer of LNG.
Additionally,Procedure 4565 Rexburg LNG Transfer Operations was revised to include the requirement to
have both the Carrier driver and the Vaporization Technician verify that all manual valves are closed prior to
connecting/disconnecting hoses.A requirement was also added to test the trailer emergency shutdowns(ESD)
prior to offloading(see Exhibit B).
In conjunction,the Rexburg LNG Truck Offloading Operations Checklist was revised to include the
verification of all manual valves being closed,the testing of the trailer ESDs, and verifying a copy of
procedure 4565 is at the offloading skid. The checklist has also been revised to include the Carrier driver
signature(see Exhibit Q.
Z NFPA 59A Standard for the Production. Storage. and Handling of Liquified Natural Gas(LNG)
2001 Edition
11.4.5. Loading or Unloading Operations
11.4.5.1.General
(g)The transfer system shall be checked prior to use to ensure that the valves are in the
correct position. Pressure and temperature conditions shall be observed during the
transfer operation.
(h) The transfer system shall be checked prior to use to ensure that valves are in the
correct position for transfer. Transfer operations shall be commenced slowly; if any
unusual variance in pressure or temperature occurs,transfer shall be stopped until the
cause has been determined and corrected.Pressure and temperature conditions shall be
observed during the transfer operation.
IGC-Rexburg LNG Transfer Operations Procedure 4565
1. GENERAL
1.2. Personnel involved in LNG transfer operations must be familiar and knowledgeable with the
transfer equipment and systems including:
1.2.1. Truck Off-Loading Skid
1.2.2. Piping Systems
1.2.3. Storage Tank
1.2.4. Pump Trailer
1.2.5. Vaporizer
1.2.6. Controls System
Finding(s)•
Personnel were not familiar with the correct positions of the valves prior to commencing off-load operations.
Intermountain Gas Resgonse
IGC acknowledges the findings brought forth by the IPUC. The Vaporization Technicians received additional
training on the LNG trailer from Kenan Advantage Group (KAG) on August 14, 2024, and August 28, 2024
(see Exhibit A). Training included the following:
• General safety overview of the trailer.
• An overview of the trailer's operation.
• Emergency Shut Down(ESD)function,testing, and locations.
• Valve orientation for travel, loading,unloading,and each valve function.
• Vent and relief functions and operations.
• Hose hookup and transfer of LNG.

EXECUTIVE OFFICES
INTERMOUNTAIN GAS COMPANY
555 SOUTH COLE ROAD-P.O.BOX 7608• BOISE,IDAHO 83707•[phone]• FAX:[phone]
Additionally,Procedure 4565 Rexburg LNG Transfer Operations was revised to include the requirement to
have both the Carrier driver and the Vaporization Technician verify that all manual valves are closed prior to
connecting/disconnecting hoses.A requirement was also added to test the trailer emergency shutdowns(ESD)
prior to offloading(see Exhibit 13).
In conjunction,the Rexburg LNG Truck Offloading Operations Checklist was revised to include the
verification of manual valves being closed and the testing of the trailer ESDs. The checklist has also been
revised to include the Carrier driver signature(see Exhibit Q.
3. 49 CFR§ 193.251 Communication Systems
Each LNG plant must have a primary communication system that provides for verbal communications between all
operating personnel at their work stations in the LNG plant.
49 CFR§ 193.2503 Operating Procedures
Each operator shall follow one or more manuals of written procedures to provide safety in normal operation
and in responding to an abnormal operation that would affect safety. The procedures must include provisions
for:
IGC-Emergency Manual for Rexburg Satellite LNG Facility
4. PERSONNEL SAFETY
It is the purpose of this section to briefly identify those areas that directly affect a response to an emergency.A
more detailed description can be found in the Rexburg LNG Fire Manual.
4.L COMMUNICATION
(a) Inside fenced area(outside of control building) ... communications between company personnel
throughout the facility will be by intrinsically safe portable radios.
NFPA 59A Standard for the Production. Storage, and Handling of Liquified Natural Gas(LNG)
2001 Edition,
11.4.6 Communications and Lighting. Communications shall be provided at loading and unloading locations so
that the operator can be in contact with other remotely located personnel who are associated with the loading
and unloading operation.
Finding(s)•
Vap. Tech at off-loading skid was not wearing the intrinsically safe portable radio provided for verbal
communication at work stations,or in emergency situations.
Intermountain Gas Resgonse
IGC acknowledges the findings brought forth by the IPUC.Procedure 4565 Rexburg LNG Transfer Operations
was revised to include the requirement to have a portable radio present at the offload skid(see Exhibit 13).
In conjunction, the Rexburg LNG Truck Offloading Operations Checklist was also revised to include the
portable radio(see Exhibit C).

EXECUTIVE OFFICES
INTERMOUNTAIN GAS COMPANY
555 SOUTH COLE ROAD-P.O.BOX 7608• BOISE,IDAHO 83707• [phone]• FAX.[phone]
4. IGC Fire Manual for Rexburg Satellite LNG Facilities
4.0.EFFECTS OF EXPOSURE TO CRYONGENIC FLUIDS
4.3.Exposure to LNG
Liquified Natural Gas exposed to atmospheric pressure is at sub-zero temperatures,approximately minus—-260'and
contact with skin will result in server frostbite.
LNG spills expose the Vap.Tech to several hazards,including localized cold effects such as cryogenic burns,
frostbite,and general cold effects(hypothermia,lung damage,asphyxia).In the event of ignition and burning of the
vapor cloud,thermal radiation hazards would also exist.Direct contact with a cryogenic liquid generally produces
rapid freezing of tissue because of the high rate of heat transfer.
Keeping the liquid confined within piping and storage vessels and wearing adequate protective apparel are the two
best ways to avoid exposure of the liquid to skin.Contact with cold gas will usually involve more body area that
liquid contact.When cold gas is released in a jet with corresponding high rate of heat transfer,the result can be rapid
freezing of large portions of the body.Equipment and structures should also be protected from contact with low
temperature vapor to prevent embrittlement of materials.
When handling of LNG or equipment which contains LNG,protective clothing should be worn to protect the skin
against the extremely low temperatures encountered.Leather gloves should always be worn when handling anything
that is or may have been in contact with LNG.Gloves should be loose-fitting so that they may be easily removed
should liquid splash onto or into them.If splashing or spraying of LNG is likely to occur,the face and eyes should be
protected with a face shield.Overalls or similar type work clothing should be worn preferably without pockets or
cuffs and trousers should be worn outside of boots.Where there is considerable risk of spilling or spraying,special
clothing which provides protection against frostbite,flash burn or fire should be worn.
NFPA 59A Standard for the Production. Storage, and Handling of Liquified Natural Gas (LNG)
2001 Edition,
9.7.Personnel Safety.
9.7.1.*Protective clothing,which will provide protection against the effects of exposure to LNG,shall be
available and readily accessible at the facility.
9.7.2.Those employees who are involved in emergency activities,as determined in accordance with 9.1.2.,
shall be equipped with the necessary protective clothing and equipment and qualified in accordance with
NFPA 600,Standard on industrial Fire Brigades
*Appendix A Explanatory Material
A 9.7.1.Protective clothing for normal liquid transfer operations should include cryogenic gloves,safety,
face shields,and coveralls or long-sleeve shirts.
Findinds)
Vap. Tech personnel were in short sleeve shirts during the off-load of—-263°F liquid natural gas. (Per
photographs and statements).
Intermountain Gas Response
IGC acknowledges the findings brought forth by the IPUC.Procedure 4565 Rexburg LNG Transfer Operations
was revised to include that the following PPE, at a minimum, shall be worn during offloading(see Exhibit B):
• FR clothing that covers the skin.
• Cryogenic gloves.
• Hard hat/face shield.
• Safety toe boots.

EXECUTIVE OFFICES
INTERMOUNTAIN GAS COMPANY
555 SOUTH COLE ROAD-P.O.BOX 7608• BOISE,IDAHO 83707•[phone]• FAX:[phone]
5. 49 CFR§ 193.2503 011erating Procedures.
Each operator shall follow one or more manuals of written procedures to provide safety in normal operation and in
responding to an abnormal operation that would affect safety.
SF 422 Job Safety Analysis/Tailgate Meetings
Instructions:on JSA Form 23023
Review the job or task to be performed and associated potential hazards with all individuals participating/observing
in,or affected by,the work activity prior to START of each job or when significant changes in the work occur.Fill
in the upper section of the form,then,review the applicable sections in the table below,provide details as requested
and ensure each individual sign form 23023(Rev 3/2020).
Policy Statement Job Safety Analysis/Tailgate Meetings(Rev Date: 1/19/2021)
2.Employee Responsibilities
2.2.Employees shall assess their work areas,adjust the JSA(Job Safety Analysis)form,and communicate any
additional changes,after the following occurrences:
2.2.3.If new individuals are entering the work area,verify they have been notified of the existing hazards
and controls by having them sign onto the current JSA form.
Findinds)•
The driver was not notified of existing hazards,controls and did not sign the 23023 form.
Intermountain Gas Resilonse
IGC acknowledges the findings brought forth by the IPUC.Procedure 4565 Rexburg LNG Transfer Operations
was revised to include the requirement to complete and review a JSA with the Carrier driver prior to beginning
offloading(see Exhibit 13).
In conjunction,the Rexburg LNG Truck Offloading Operations Checklist was also revised to include the JSA
completion and review. The checklist has also been revised to include the Carrier driver signature(see Exhibit
C).
Please contact Josh Sanders at(701)222-7773 with questions or comments.
Respectfully Submitted,
k&44���
Pat Darras
Vice President,Engineering&Operations Services
Intermountain Gas Company

Exhibit A
Department Name Date
Rexburg LNG Facility
Name Employee #
671655
L 9-{
r
Topics:
• LNG Trailer related topics:
• General safety overview for the trailer
• An overview of the trailer's operation
■ ESD function,testing and locations
• Valve orientation for travel,loading,unloading and each valve's function
• Vent and relief functions and operations
• Hose hookup and transfer of LNG
Trainer: Bret Barnett—KAG Regional Safety and Security Manager

Department Name Date
Rexburg LNG Facility 8/28/24
Name Employee #
DAwZ wlbON 7 q 7.?.?
�-7 /ass
Topics:
• LNG Trailer related topics:
• General safety overview for the trailer
■ An overview of the trailer's operation
• ESD function,testing and locations
• Valve orientation for travel,loading,unloading and each valve's function
• Vent and relief functions and operations
• Hose hookup and transfer of LNG
Trainer: Bret Barnett— KAG Regional Safety and Security Manager

Exhibit B
6INTERMOUNTAINO '
Standard Operating Procedure
GAS COMPANY
A&VtWdII8g0fMDUHegources Group,Inc.
In the Community to serve
Title: Rexburg LNG Transfer Operations
Department: Engineering
Procedure Number: 4565.4 Revision Date: September 10, 2024
Revision Summary
Rev. 1—Original procedure
Rev. 2—Replaced Teton District Manager with Supervisor, Engineering Services in Administration section.
Rev. 3—Minor clarification/name change of operations checklist for consistency with the actual form name.
Rev. 4—Rewrite for more efficient flow and to eliminate redundancies.
References:
Regulations
193.2513 -Transfer Procedures
Forms
Rexburg LNG Truck Off Loading Operations Checklist
Purpose:
Provide safety and operational guidelines for the transferring of LNG from LNG trailers to the storage
tank.
Scope:
Applies to all equipment and operations as part of LNG transfer operations from the Truck Offloading
Skid to the Storage Tank(s).
Definitions:
1. Liquefied Natural Gas (LNG) ... cryogenic fluid at a temperature near minus 260 degrees Fahrenheit.
2. Carrier ... owner and/or driver of the LNG trailer responsible for the safety and operation of the truck and
trailer.
Administration:
A. The Supervisor, Engineering Services is responsible for the annual review and update of this Procedure.
Procedure 4565.4 Page 1 of 6

'_<*_� Standard Operating Procedure
6INTERMOUNTAINO '
GAS COMPANY
A SAWdI8ry0/MDUHegources Group,Inc.
In the Community to serve
Procedure:
1. GENERAL
1.1. LNG may only be off-loaded from LNG trailers designated and certified to transport LNG.
1.2. Personnel involved in LNG transfer operations must be familiar and knowledgeable with the transfer
equipment and systems including.
1.2.1. Truck Off Loading Skid.
1.2.2. Piping Systems.
1.2.3. Storage Tank.
1.2.4. Pump Trailer.
1.2.5. Vaporizer.
1.2.6. Controls System.
1.3. At minimum, personnel shall wear the following protective clothing during off-load.
1.3.1. FIR clothing that covers the skin.
1.3.2. Cryogenic gloves.
1.3.3. Hard hat/face shield.
1.3.4. Safety toe boots.
1.4. A dry chemical fire extinguisher shall be available in the immediate vicinity of the Truck Offloading Skid.
1.5. A portable radio shall be present at the offload skid.
2. PROCEDURE
2.1. A minimum,two (2) LNG Vaporization Technicians (Vap. Techs)shall be present for transfer operations. One
(1)Vap.Tech shall be at the Truck Offloading Skid at all times when transfer equipment is in operation, and
the LNG trailer is connected to the Truck Offloading Skid.
2.2. Prior to allowing entry of the transport truck into the facility the Vap.Tech shall:
Procedure 4565.4 Page 2 of 6

'-<*-� Standard Operating Procedure
6INTERMOUNTAINO '
GAS COMPANY
A SAWd18ry0/MDUHegources Group,Inc.
In the Community to serve
2.2.1. Verify and sign in the Carrier driver. Carrier driver shall provide the following:
2.2.1.1. Current state and federal inspection certification/documentation.
2.2.1.2. LNG trailer pressure data.
2.2.2. Check Bill of Lading to verify contents of Carrier is LNG and is compatible with LNG tank.
2.2.3. Vap. Tech and Carrier driver shall visually inspect the exterior of the truck and LNG trailer units for
safety violations, leaks, or other signs of hazardous conditions.
2.2.3.1. If any hazardous conditions or violations are evident,the LNG trailer shall not be allowed
entry into the facility until deficiencies are resolved.
2.2.4. Remove ignition sources from offloading areas.
2.2.5. Check spill pit for standing water and remove prior to offloading.
2.3. Assist the Carrier driver with positioning the truck and LNG trailer on the Truck Offloading skid to ensure
hoses easily reach the LNG trailer connections. Prohibit backing the truck and LNG trailer in the transfer area
unless personnel are positioned at the rear of the trailer to aid the driver.
2.4. Prior to beginning offloading:
2.4.1. Verify a copy of procedure 4565—Rexburg LNG Transfer Operations is available at the Truck
Offloading Skid.
2.4.2. Visually inspect Truck Offloading Skid and Storage Tank valves.
2.4.3. Confirm storage tank has adequate capacity to receive LNG from Carrier.
2.4.4. Visually inspect transfer hoses and connections.
2.4.5. The Carrier driver shall set the truck brakes,turn off the truck engine, and exit the cab.
2.4.5.1. Carrier driver shall not reenter the cab of the truck until authorized by Vap. Tech.
2.4.5.2. Truck keys shall be placed in a designated area until offloading is complete.
2.4.6. Place wheel chocks at LNG trailer tires.
2.4.7. A JSA shall be completed and reviewed with the Carrier driver.
2.4.8. The Carrier driver shall inspect valves,valve box, and pressure build coil on the trailer to ensure all
components are damage free and in the proper position for operation.
Procedure 4565.4 Page 3 of 6

1_<*_� Standard Operating Procedure
6INTERMOUNTAINO '
GAS COMPANY
A Sub5d18g0/MDUHegources Group,Inc.
In the Community to serve
2.4.8.1. If any hazardous conditions or violations are evident, offloading shall not begin until
deficiencies are resolved.
2.4.9. Connect the LNG trailer grounding wire.
2.4.10. The Carrier driver and Vap. Tech shall verify all manual valves are closed before
connecting/disconnecting hoses.
2.4.11. The Carrier driver shall visually verify with the Vap. Tech the location of truck and LNG trailer
emergency shutdowns (ESD).
2.4.11.1. Test trailer ESD and visually observe fire block valves drop.
2.4.11.2. After trailer ESD test,verify with carrier driver that tractor and trailer air pressure are at
max operating pressure so ESDs the trailers will be fully functional during unload.
2.4.12. Vap. Tech shall note vapor pressure and liquid level.
2.4.13. Connect fill hose and vapor return hose to the LNG trailer.
2.4.13.1. The area around the Truck Offloading Skid shall never be left unattended once the LNG
hoses are connected to the LNG trailer.
2.4.14. Vap. Tech shall contact Gas Control.
2.4.14.1. Gas Control shall contact the onsite Vap.Tech for alarms received during offloading.
2.4.14.2. If the Vap. Tech cannot be reached,Gas Control shall follow alarm response procedures.
2.4.15. Complete Rexburg LNG Truck Offloading Operations Checklist.
2.5. Begin offloading:
2.5.1. Verify tank pressure and level will accept load.
2.5.2. Place LNG facility into "Truck Unload" mode on HMI screen.This enables the three (3)valves used
to unload the LNG trailer.
2.5.3. Close tank vapor valve FCV-127 using manual over-ride on HMI.
2.5.4. Vap. Tech shall begin pressure building in trailer with a target of 60 psig.
2.5.4.1. Carrier driver shall be present during the pressure build and until product starts offloading
from the trailer.
Procedure 4565.4 Page 4 of 6

'_<*_� Standard Operating Procedure
6INTERMOUNTAINO '
GAS COMPANY
A Sub5d18g0/MDUHegources Group,Inc.
In the Community to serve
2.5.5. Verify Truck Offloading Skid block valves V-404 and V-410 are closed.
2.5.6. Open Truck Offloading Skid valves V-404 and V-410.
2.5.7. The following is required from the Control Panel in the Control Building:
2.5.7.1. Open 50-foot valve FCV-517.
2.5.7.2. Open LNG tank top fill valve FCV-106 or bottom fill valve FCV-109 based on tank pressure
considerations.Top fill will lower tank pressure while bottom fill tends to increase
pressure.
2.5.7.3. Verify that the boiloff heater outlet valve TCV-510 is closed.
2.5.8. When pressure in the LNG trailer exceeds pressure in LNG storage tank, slowly open LNG trailer
liquid valve to pressurize the line.The LNG will cool the transfer line to the tank and will cause a
slight pressure increase in the tank due to the vapor created during this process.
2.5.8.1. Open Truck Offloading Skid hose vent valves V-403 and V-409, if applicable.
2.5.8.2. Purge each hose for 30 seconds cracking open the Carrier liquid and vapor valves.After
purging, close LNG trailer valves and Truck Offloading Skid vent valves V-403 and V-409, if
applicable.
2.5.9. When LNG begins to flow into the tank,the tank pressure will decrease slightly due to the collapsing
of the vapor by the cold liquid when using the top fill line.
2.6. During offloading:
2.6.1. Vap. Tech shall monitor the pressure in both the tank and the LNG trailer to ensure safe operation.
The display PI-102A on the Truck Offloading Skid indicates pressure in the LNG trailer.
2.6.1.1. Note: If the transfer rate slows due to an increase in the LNG tank pressure, manually
open valve FCV-127 to decrease tank pressure and allow the tank vapor to flow to the
boiloff skid. Close FCV-127 when PT-102 is within three (3) psig of PT-104.
2.6.2. Vap. Tech shall prohibit and/or monitor vehicle traffic within 25' of Truck Offload Skid.
2.6.3. Ensure Carrier driver does not reenter the cab.
2.6.4. Ensure non-essential personnel are away from the Truck Offload Skid.
2.7. When LNG transfer is complete, and the storage tank and LNG pressures have equalized:
2.7.1. Close Truck Offloading Skid valves V-404 and V-410.
Procedure 4565.4 Page 5 of 6

'_<*_� Standard Operating Procedure
6INTERMOUNTAINO '
GAS COMPANY
A SAWd18ry0/MDUHegources Group,Inc.
In the Community to serve
2.7.2. Vap. Tech shall close LNG trailer valves.
2.7.3. Vent liquid hose through valve V-403.
2.7.4. When PI-402 indicates ZERO (0) psig and venting at drain header stops, disconnect from LNG trailer
and cap liquid hose and place in hose rack.
2.7.5. If vapor hose was used,vent through valve V-409 until PI-408 indicates ZERO (0) psig and venting at
drain header stops. Disconnect from LNG trailer,cap vapor hose, and place in hose rack.
2.7.6. Note trailer vapor pressure and liquid level.
2.7.7. Disconnect ground wire.
2.7.8. Carrier driver shall verify valves are in correct position for transport and close doors on back of LNG
trailers.
2.7.9. Remove wheel chocks.
2.7.10. Ensure area is safe to allow Carrier driver to drive off of the Truck Offloading Skid and exit the
facility.
2.7.11. Provide keys to and sign out Carrier driver.
2.7.12. Instruct Carrier driver to blow down trailer pressure, if needed, to the safe transport pressure
outside of fenced area.
2.7.13. Check the delay on FCV-106 valve and FCV-109 valve is OPEN on HMI panel.
2.7.14. Re-open boiloff valves and return boiloff heater to safe operations.
2.7.15. Contact Gas Control.
2.7.16. Ensure Rexburg LNG Truck Offloading Operations Checklist is complete, signed and dated by Vap.
Tech and Carrier driver.
2.7.17. Completed checklist shall be uploaded to Share Point.
2.7.18. A separate checklist is required for each trailer offload.
Procedure 4565.4 Page 6 of 6

Exhibit C
REXBURG LNG TRUCK OFF LOADING OPERATIONS CHECKLIST
Intermountain Gas Company Rexburg LNG Facility
Date: Destination
Trailer Owner Trailer Number
PRIOR TO ALLOWING TRUCK ENTRY INTO FACILITY Notes/Comments
1 Verify and sign in Carrier driver.
2 Verify Carrier's current state/federal truck and trailer inspection
documentation and LNG trailer pressure data.
3 Read beginning trailer pressure from trailer gauge psig
4 Read beginning trailer level from trailer gauge inches
5 Check Bill of Lading to verify contents of Carrier is LNG and is
compatible with LNG tank.
Vap Tech and Carrier driver shall visually inspect the exterior of the
6 truck and LNG trailer units for safety violations, leaks, or other signs
of hazardous conditions.
7 Check spill pit for standing water and remove prior to offloading
8 Remove sources of ignition from offloading area.
PRIOR TO BEGINNING OFFLOADING
9 Ensure truck is positioned to ensure hoses easily reach trailer
connections.
10 Verify a copy of procedure 4565— Rexburg LNG Transfer
Operations is available at offload skid.
11 Verify a portable radio is present at the offloading skid.
12 Visually inspect Truck Offloading Skid and Storage Tank valves.
13 Confirm storage tank has adequate capacity to receive LNG from
Carrier.
14 Visually inspect transfer hoses and connections.
15 Carrier driver and Vap Tech shall verify all manual valves are closed.
16 Test trailer ESDs and visually observe fire block valves have
dropped
After trailer ESD test, verify with driver that tractor&trailer air
17 pressure are at max operating pressure so ESDs on trailer will be
fully functional during unload.
Trailer air pressure observed. PSI
18 Verify the driver set truck brakes, turned off truck engine, and exited
the cab.
19 Place truck keys in designated area.
20 Complete JSA and review with Carrier driver.
Carrier driver shall inspect valves, valve box, and pressure build coil
21 on the trailer to ensure all components are damage free and in the
proper position for operation.
22 Connect the LNG trailer grounding wire.
9/10/24

23 Carrier driver shall visually verify with the Vap Tech the location of
truck and LNG trailer emergency shut downs (ESD).
24 Note vapor pressure and liquid level
25 Connect fill hose and vapor return hose to the LNG trailer.
26 Contact Gas Control
WHEN LNG TRANSFER IS COMPLETE
27 Close Truck Offloading Skid valves V-404 and V-410.
28 Vap Tech shall close LNG trailer valves.
29 Vent liquid hose through valve V-403.
30 Empty transfer hoses prior to disconnection from LNG trailer
31 Disconnect transfer hoses after purging completed
32 Read ending trailer pressure from trailer gauge psig
33 Read ending trailer level from trailer gauge inches
34 Disconnect ground wire.
35 Carrier driver shall verify valves are in correct position for transport
and close doors on back of LNG trailer.
36 Remove wheel chocks.
37 Verify area is safe to allow Carrier driver to drive off the Truck
Offloading skid and exit the facility.
38 Provide keys to and sign out Carrier driver.
39 Instruct Carrier driver to blow down trailer pressure, if needed, to
safe transport pressure outside of fenced area.
40 Check that the delay is OPEN on HMI panel.
41 Re-open boiloff valves and return boiloff heaters to safe
operations.
42 Contact Gas Control.
43 Copy of Bill of Lading (yes/no)
44 Copy of chromatograph report (yes/no)
Employee Signature Date
Carrier Driver Signature Date
9/10/24