I201902 NOPV Response

EXECUTIVE OFFICES
INTERMOUNTAIN GAS COMPANY
555 SOUTH COLE ROAD•P.O.BOX 7608•BOISE,IDAHO 83707• [phone]• FAX:[phone]
February 22,2019
Mr.Darrin Ulmer
Pipeline Safety,Programs Manager
Idaho Public Utilities Commission
P.O.Box 83720-0074
Boise,ID 83720-0074
Subject: Response to January 28,2019 Notice of Probable Violations—Owyhee District
Dear Mr. Ulmer,
This letter is intended to address the January 28,2019 Notice of Probable Violations identified by the Idaho Public
Utilities Commission(IPUC)during the January 18,2019 follow-up High Pressure Service Set(HPSS)inspection of
Intermountain Gas Company's(IGC)equipment in the Nampa District. Listed below are the stated probable violations
and the respective corrective actions taken by IGC.
PROBABLE VIOLATIONS
1. 49 CFR 4 192.605(a)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.
IGC's Standard Operating Procedure 3111.4 High Pressure Service Sets(HPSS)
-Definitions 4. Small HPSS ... Regulating facility capable of service up to two(2)service lines up to a
maximum combined load of 700 CFH and may be located remotely or at the building.
-Procedure 1.5. Standard HPSS facilities that serve three or more service lines shall be reclassified and
maintained as a district regulator station.
Finding:
HPSS 00219-325 is supplying three homes located at 17535, 17545,and 17555 US HWY 95,Homedale,ID.
HPSS 10849-371 is supplying apartments 3-4,5-6 and 7-8 located at 812 4'St N,Nampa,ID.
HPSS 14503-371 is supplying apartments 1,2 and 4 with an idle riser at 5 and cut off riser at 3 located at 123
91 Ave N,Nampa,ID.
Intermountain Gas Response
Intermountain Gas acknowledges that some service lines, including 00219-325, 10849-371 and 14503-371 have more than
two service lines downstream of the HPSS.
The HPSS Inspection Program which began in 2014 identifies HPSSs serving more than two service lines. The specific
yes/no question on the HPSS Inspection Form is"HPSS serving less than three service lines".As HPSSs with more than
two service lines are identified,remedial action is taken. The preferred mitigation is to connect the service lines to a
distribution pressure system with a MAOP of 60 psig.Often this mitigation approach requires the installation of a district
regulator station or new distribution main the following budget year. Service lines 10849-371 and 14503-371 were
identified in 2018.Both are included in a downrate scheduled for the summer of 2019.The downrate will reduce the
operating pressure of 14,160 feet of main to 55 psig allowing the abandonment of approximately 200 HPSSs.
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The HPSS on service line 00219-325 was identified on August 29,2018. In response to your January 28,2019 letter, IGC
accelerated the mitigation schedule. On February 11,2019,IGC installed an HPSS to serve 17535 HWY 95 (service line
00220-325).The HPSS identified now serves 17555 HWY 95 (00218-325)and 17545 HWY 95 (00219-325).
In addition to the above actions, Intermountain Gas will review completed HPSS Inspection forms to confirm HPSSs
identified as serving more than two service lines are either mitigated or scheduled for mitigation. Intermountain Gas will
also formalize the mitigation tracking of HPSSs serving more than two customers.
Please contact Josh Sanders at(701)222-7773 with questions or comments.
Respec lly Submitted,
Pat Darras
Vice President, Engineering&Operations Services
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