HomeMy WebLinkAboutTANK LINING 2024
1301 Academy Ct.
Fort Collins, CO 80524
www.cgrs.com
800.288.2657
Fiesta Liquor
2023 Baker St.
Bakersfield, CA 93304
CGRS Project # 28445
Fiesta Liquor – Bakersfield, CA
UST LINING INSPECTION REPORT
August 14, 2024
Prepared for:
Fiesta Liquor
TABLE OF CONTENTS
1.0 INTRODUCTION .......................................................................................................................................................... 3
2.0 SCOPE ......................................................................................................................................................................... 3
3.0 TANK INSPECTION AND FINDINGS ........................................................................................................................ 3
3.1 Subject UST........................................................................................................................................................... 3
3.2 Inspection .............................................................................................................................................................. 4
3.3 Dry-Film thickness testing ..................................................................................................................................... 4
4.0 CONCLUSION ............................................................................................................................................................. 5
APPENDICES
Appendix A: Photo Log
Appendix B: Certifications
April 28, 2023
1.0 INTRODUCTION
This report summarizes the internal inspection and determination of fitness for continued service of three (3) existing
underground fuel storage tanks (USTs) located at 2023 Baker St. Bakersfield, CA 93305 (Fiesta Liquor). Three
USTs on site were inspected as part of the 10 and 5-year inspection program. All three tanks are 12,000-gallon
Fuel UST’s. As a part of routine maintenance and EPA CFR 40 Part 280.21 and CCR Title 23-2663 (h), CGRS, Inc.
of Fort Collins, CO performed 5-year internal lining inspections. This report presents UST shell and bulkhead coating
thicknesses and visual inspection results. The report also provides CGRS’s opinion on the USTs fitness for
continued use.
2.0 SCOPE
CGRS was hired by Fiesta Liquor to provide internal UST lining inspections. The scope of the work included making
the USTs safe for confined space entry, clean the USTs for observations, visually evaluate the USTs to determine
if the tanks have any major or minor coating damage. Perform dry-film (coating) thickness readings and visual
inspections.
The inspection shall follow a modified fit-for-service analysis as prescribed by American Petroleum Institute API
1631 “Interior Lining and Periodic Inspection of Underground Storage Tanks,” National Leak Prevention Association
(NLPA) Standard 631, and industry-standard structural standards for UL-1316 tanks.
To meet the Water Board requirements of CCR Title 23-2663, Interior Tank Lining Requirements, the special
inspector (Niko Retes NACE Coatings Inspector Level 2) entered and inspected the entire interior surface of the
tank and certified the tank based on the inspection criteria below.
3.0 TANK INSPECTION AND FINDINGS
3.1 Subject UST
Fiesta Liquor operates a service station and convenience store providing diesel, unleaded, and premium fuels at
the site. The manufacturer and age of the UST was not identified. The dimensions of the tanks are as follows:
a.) UST-1 8’ X 33’
b.) UST-2 8’ X 33’
c.) UST-3 8’ X 33’
The tanks are buried approximately 4-feet below a concrete surface deck. The tank was accessed through the fill
sump with an integral tank manway lid. Photographs are provided in Appendix A.
The Steel Tank was inspected based on the following criteria:
a) CGRS cleaned the tank so that no residue remained on the tank walls.
b) CGRS visually checking the tank interior and lining for discontinuity, compression, tension cracking, and
corrosion.
c) For steel tanks, testing the entire tank interior using a thickness gauge on a one-foot grid pattern with
metal wall thickness recorded on a form that identifies the location of each reading in order to verify that
average metal thickness is greater than 75 percent of the original wall thickness.
d) Testing for liner thickness and hardness of the lining in accordance with nationally recognized industry
codes to verify that the lining meets the standards under which the lining was applied.
e) For steel tanks, testing the lining using an electrical resistance holiday detector in accordance with
nationally-recognized industry codes. The owner or operator shall have all holidays repaired and
checked in accordance with nationally recognized industry codes.
f) Certification from the special inspector or coatings expert that the tank is: Not Suitable for continued
use.
3.2 Inspection
CGRS Inc. prepared the USTs for entry by opening the fill port sump, removed fill and vapor sump to access the
UST’s manway lid. The team purged the USTs of vapors, and conducted confined space protocol air monitoring,
prior to entering the tanks and inspecting the USTs.
Sediment and remaining fuel were cleaned from the tank. Once the fuel was removed, all three tanks showed signs
of advanced damage. From visual inspections, it appeared that an original liner was placed in all three tanks, but
this liner was too thin. Average original liner thicknesses were between 19 and 43mils, significantly below the
required 100 mils needed to line a UST.
It appears that after the original liner a second liner was attempted. The adhesion of the second liner was poor.
Likely due to a poor surface prep profile, almost all of the second liner had been delaminated and was no longer
present. All tanks had areas greater than 10 percent that were bare steel. No advance corrosion or pitting was
observed in these areas.
3.3 Dry-Film thickness testing
Typically, a Dry-Film Thickness gauge is used to measure coating thickness. In this instance, the coating was
greatly deteriorated and it was not possible to properly utilize the dry-film thickness tester. In Appendix A, the photo
log displays the extent of the coating deterioration, showing large portions of the coating falling off the steel. It was
also noted that the first coating that was applied was deemed too thin and a second coating was applied on top of
the first coat.
In the California Code of Regulations, Title 23, Division 3, Chapter 16 § 2661. Requirements for Repairing
Underground Storage Tanks it states “A tank may be repaired once using the interior lining method specified in
section 2663. A previously lined tank may not be repaired using the interior lining method.”
For safety purposes, the interior lining can only be applied once, which in this case it was lined twice.
In the California Code of Regulations, Title 23, Division 3, Chapter 16 § 2663. Interior Tank Lining Requirements it
also states the following:
“Tank lining may be used to satisfy part of the upgrade requirements of section 2662 or to repair a tank pursuant to
section 2661. However, a tank that has been repaired using the interior lining method may not be repaired a second
time with the interior lining method. The evaluations described in subdivisions (b) and (c) of this section shall be
completed before the lining of a primary container may be authorized by the local agency. The local agency shall
deny the proposed lining if the owner fails to demonstrate that the lined primary container will provide continued
containment based on the evaluations described in subdivisions (b) and (c).
(h) If a steel tank is lined for the purpose of satisfying the requirements of section 2662(c), or if any tank is repaired
using the interior lining method, it shall be inspected by a coatings expert or special inspector within 120 months of
lining and every 60 months thereafter.”
4.0 CONCLUSION
Limitations: This inspection was conducted in accordance with generally accepted industrial standards and
represents site conditions during the time of the visit. The inspection did not include review of design drawings or
weld inspection reports. If external UTs were performed, they are an average and may not find all flaws. As such
the limits of this report are as an overall survey of the tank this report does not serve as a guaranty of future system
performance. Due care has been taken to verify and confirm the accuracy of this report.
The inspection focuses on a failure mode which can be determined by visual and may not identify modes of failure
such as stress corrosion cracking, hydrogen embrittlement, and micro effects of metal flaws in steel manufacturing
which would require a more extensive non-destructive and destructive testing. A safety factor is used to
accommodate these unknowns and is typical in engineering analysis.
As such, CGRS finds the USTs ARE NOT SUITABLE for continued use.
If you have any questions please contact the undersigned inspector, Niko Retes at (360) 823-6265.
Sincerely,
CGRS, Inc.
Niko Retes., Project Manager.
APPENDIX A
Photo Log
1 | P a g e
Fiesta Liquor | August-2024| Photo Log
2
2 | P a g e
Fiesta Liquor | August-2024| Photo Log
3 | P a g e
Fiesta Liquor | August-2024| Photo Log
END OF PHOTOS
APPENDIX B
CERTIFICATIONS
APPENDIX B
CERTIFICATIONS
APPENDIX B
CERTIFICATIONS
APPENDIX B
CERTIFICATIONS