A202502 LOC

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#A202502
Alicia Gibbs
Avista Corporation
1411 Mission Ave, MSC-6
P.O. Box 3727
Spokane, WA 99220-3727
Dear Mrs. Alicia Gibbs:
On July 29, 2025, the Idaho Public Utilities Commission ("Commission"), Pipeline Safety
Division ("Staff'), conducted a Sandpoint District, Idaho Field Inspection of Avista Corporation
pursuant to Chapter 601 of Title 49, United States Code.
As a result of the inspection, it appears there are area(s) of concern that do not fully meet the
intent of the pipeline safety regulations Title 49, Code of Federal Regulations, Part 192.
The item(s) listed below are of concern:
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. (2) Controlling corrosion in accordance with the operations and maintenance
requirements of Subpart I of this part.
2025 Gas Standards Manual
(2.32) Cathodic Protection (Cathodic Protection Design)
Cathodic Protection-It is not economically feasible to design, apply, install and maintain
a coating that will completely insulate metal pipe from the soil electrolyte. Instead, the
protection provided by an economical pipe coating is supplemented with the application of
cathodic protection, an electromechanical method that forces the metal to become cathodic
to its environment.
AVISTA SANDPOINT,IDAHO FIELD INSPECTION LETTER OF CONCERN— Page 1 of 3

Impressed Current System-In areas where current requirements are higher, impressed
current protection systems be used. These systems normally utilize a rectifier which
changes alternating current (AC) to direct current (DC) which then is caused to flow into
the soil through an anode and ultimately to flow onto the pipeline thereby cancelling all
undesired corrosion current.
2. Appendix D to Part 192—Criteria for Cathodic Protection and Determination of
Measurements
I. Criteria for cathodic protection—
A. Steel, cast iron, and ductile iron structures.
(1) A negative (cathodic) voltage of at least 0.85 volt, with reference to a saturated
copper-copper sulfate half cell. Determination of this voltage must be made with the
protective current applied, and in accordance with sections II and IV of this appendix.
3. 49 CFR 4192.465 External corrosion control: Monitoring and remediation
(a) Each pipeline that is under cathodic protection must be tested at least once each calendar
year, but with intervals not exceeding 15 months, to determine whether the cathodic
protection meets the requirements of 19� 2.463. However, if tests at those intervals are
impractical for separately protected short sections of mains or transmission lines, not in
excess of 100 feet (30 meters), or separately protected service lines, these pipelines may
be surveyed on a sampling basis. At least 10 percent of these protected structures,
distributed over the entire system must be surveyed each calendar year, with a different
10 percent checked each subsequent year, so that the entire system is tested in each 10-
year period. Otherwise protected against such damage.
(b) Cathodic protection rectifiers and impressed current power sources must be periodically
inspected as follows:
(1) Each cathodic protection rectifier or impressed current power source must be inspected
six times each calendar year, but with intervals not exceeding 21/2 months between
inspections, to ensure adequate amperage and voltage levels needed to provide cathodic
protection are maintained. This may be done either through remote measurement or
through an onsite inspection of the rectifier.
Findim(s)
During the 2025 Sandpoint, Idaho Field Inspection, Commission Staff witnessed a low
Cathodic Protection reading of-0.764mV on Reg Station 206. The associated rectifier was
later found in the off position.
AVISTA SANDPOINT,IDAHO FIELD INSPECTION LETTER OF CONCERN— Page 2 of 3

The above-mentioned item(s)were brought to the attention of Avista representatives during the
inspection. We request that you review these matter(s) and respond in writing within 30 days
regarding the above issue(s) including any planned corrective actions.
If you have any questions concerning this notice, please contact me at(208) 334-0333. All
written responses should be addressed to me at: 11331 W Chinden Blvd, Ste 201-A, Boise, Idaho
83714 or you can fax your response to [phone].
Because of the good faith that you have exhibited up to this time, we expect that you will take
action to bring your program into compliance with pipeline safety regulations.
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]
AVISTA SANDPOINT,IDAHO FIELD INSPECTION LETTER OF CONCERN- Page 3 of 3