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Home My WebLink AboutDERR-2024-012220 1301 Academy Ct. Fort Collins, CO 80524 www.cgrs.com 800.288.2657 Jackson Energy Cottonwood Heights 7006 S. 2000 E. Cottonwood Heights, UT 84121 Project ID: 28700 Connect Project No: 22341 UST INSPECTION AND ASSESSMENT Prepared for: September 14, 2024 2 UST Inspections and Lining 2024 TABLE OF CONTENTS 1.0 INTRODUCTION .......................................................................................................................................................... 3 2.0 SCOPE ......................................................................................................................................................................... 3 3.0 TANK INSPECTION AND FINDINGS ........................................................................................................................ 3 3.1 Subject USTs ......................................................................................................................................................... 3 3.2 Entry and Cleaning ................................................................................................................................................ 3 3.3 References ............................................................................................................................................................ 4 3.4 Structural Integrity and Fitness-for-Service Criteria .............................................................................................. 4 3.5 Results and Determination .................................................................................................................................... 4 4.0 REPAIRS AND LINING ............................................................................................................................................... 5 4.1 Repairs, Modifications ........................................................................................................................................... 5 4.2 Lining ..................................................................................................................................................................... 5 5.0 CONCLUSION ............................................................................................................................................................. 6 FIGURE Site Map Vicinity Map APPENDICES Appendix A: Photo Log Appendix B: Calculations Appendix C: Test Results 3 UST Inspections and Lining 2024 1.0 INTRODUCTION This letter summarizes the inspection and determination of fitness for continued service of the existing underground storage tanks (USTs) located at the Jackson Energy facility, 7006 S. 2000 E. Cottonwood Heights, UT 84121 . This report addresses the cause of the USTs operating outside their intended function, suitability of the USTs for repairs or liner, and fit for continued use of the subject USTs. The three USTs are double walled steel tanks wrapped in clad holding Premium Gasoline-PRE (UST-1) and Unleaded Gasoline-RUL, (UST-2 and UST-3). Recently, fuel was detected in the interstice of both UST-1 and UST-2, Figure-2 presents the tank layout. Therefore, CGRS, Inc. (CGRS) was hired by Jackson Energy to perform internal tank inspections and evaluate the suitability of the USTs for repairs or liner and fit for continued use. Once the problem was identified, CGRS would evaluate the USTs to determine if the tank is suitable for repair and relining and to evaluate the repair method. 2.0 SCOPE Tank performance and suitability for repairs followed 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 analysis methodology for Underwriters Laboratory (UL) UL-1316 tanks. UT measurements were taken to verify the thickness was adequate for continued use. 3.0 TANK INSPECTION AND FINDINGS 3.1 Subject USTs The site operations include three 12,000-gallon USTs containing RUL gasoline and PRE gasoline. The USTs are double walled steel tanks, built to UL-58 standards, each with a clad fiberglass cover. The USTs were installed in August 1989. UST-1 through UST-3 were measured approximately 9’-3” in diameter by 23’-10” long (12,000-gallons). The tanks are buried beneath a 8-inch slab of concrete surface deck and approximately 3.5-feet of pea gravel. Photographs are provided in Appendix A. 3.2 Entry and Cleaning In August 2024 Emergency Environmental Services, (EES) prepared the USTs for entry by cutting the overlaying concrete, excavating overlying soil to the tank top and installing steel caisson shoring to prevent collapse. Once shoring was in place the CGRS team purged the UST compartment of vapors, cut access ports at the top of the tanks, and conducted confined space protocol air monitoring, prior to entering the tank compartments and inspecting the USTs. UST-1 through UST-3 were emptied of fuel prior to CGRS arriving on site. CGRS de-gassed all three USTs using a pneumatic venturi to exchange vapors with air. Once the USTs were made safe (Zero LEL) the USTs were cut open using pneumatic tools. All three UST’s were cleaned of residual fuel/sludge and barreled up in 55 gallon open top drums for proper disposal. 4 UST Inspections and Lining 2024 UST-1 & UST-2 had pinholes in the primary tanks, some water was found mixed in with the fuel. The interstice ports are made of PVC and could be the potential entry point for water. All three USTs were sandblasted to an SPCC SP-10 (NACE 2) near white metal blast profile. All sandblast media was removed and vacuumed clean from the tank prior to installing the liner. 3.3 References UL-58 “Standard for Steel Underground Tanks for Flammable and Combustible Liquids ” recommends the original steel thickness be ¼-inch thick. These tanks had an outer steel wall ¼-inch thick, but the inner steel tank was likely thinner, about 0.215 inches based on non-corroded bulkhead UT measurements and all other measurements made around the entirety of the tank. Both steel shells ensure thickness values are within adequate amounts that provide structural integrity of the vessel. 3.4 Structural Integrity and Fitness-for-Service Criteria American Petroleum Institute (API) 1631: Interior Lining and Periodic Inspection of Underground Storage Tanks standard provides guidance on determining whether a UST is suitable for installing a liner or repair . Four criteria are to be evaluated: 1.The UST does not have perforations exceeding: a.Any perforation larger than 1-½ in. in diameter, except under the gauging opening where the perforation may be no larger than 2 ½ in. in diameter. b.5 perforations, and none larger than ½ in. diameter, in any 1 square foot (s.f.) area. c.20 perforations, and none larger than ½ in. in diameter in any 500 s.f. area. 2.The UST does not have any cracks greater than 6-Inches in length. 3.The UST has original roundness and has no flat spots. 4.Average UT measurements cannot be below 75% of the original design thickness. Assessment of fitness-for-service is calculated on these indications. Inspection work was conducted by a Steel Tank Institute (STI) inspector. 3.5 Results and Determination API 1631 criteria 1. After full internal shell and bulkhead cleaning of UST-1 through UST-3, no penetrations greater than Criteria 1 were observed in UST-1 through UST-3. UST-1 and UST-2 had micro corrosion holes in the primary tanks, but hole sizes were less than 1-inch and did not extend over a three- inch area. UST-2 had 8 holes, UST-1 had 5 holes, and UST-2 had no visible holes. Therefore, the USTs meet the perforation requirements and ARE SUITABLE for a liner or repair. API 1631 criteria 2. After full internal shell and bulkhead cleaning of UST-1 through UST-3, no cracks were observed in the USTs indicating a breach. Therefore, the USTs meet the criteria requirements and ARE SUITABLE for a liner or repair. API 1631 criteria 3. A UST must maintain the original structural rigidity to be eligible for repair. CGRS did not observe any deformation in UST-1 through UST-3 tank’s shell structure (See Appendix B). The 5 UST Inspections and Lining 2024 roundness readings for UST-1 to UST-3 indicated equal to or less than 0.6 percent variances, within the 2 percent tolerance. Therefore, the USTs meet the structural rigidity requirements and ARE SUITABLE for a liner or repair. API 1631 criteria 4. UT measurements averages for all three tanks are listed below: High: 0.247-inches Low: 0.189 - inches Avg: 0.2041 - inches σ: 0.013 4.0 REPAIRS AND LINING CGRS found holes in UST-1 and UST-2, The holes were repaired using fiberglass patch repairs, all repaired areas where blasted prior to lining the USTs. All three tanks were lined using Enviroline 125u high build epoxy. All three UST’s inner and outer tanks were pressure and vacuum tested. Results are presented in Appendix C. All tanks passed tightness testing after the tanks had been closed but prior to returning to service. 4.1 Repairs, Modifications After cleaning and abrasion blasting UST-1, UST-2 and UST-3, the blast profile was inspected and determined to have no penetration or cracks. Epoxy and fast cure epoxy layers were applied at the seams for additional coverage. All repairs were inspected and found to be sound. 4.2 Lining After cleaning Twenty-four hours after the initial lining BAT&C entered the tank and hand coated any observable holidays. Thin areas were hand coated with additional epoxy. The holiday testing did not find any breaks in the liner. 6 UST Inspections and Lining 2024 5.0 CONCLUSION CGRS found the USTs suitable for repair. The subject USTs were found to be structurally sound by measurement and visual inspection. Repairs and liners were installed correctly and were in good condition. 1.No perforations exceeding API 1631 criteria were found in the USTs. 2.No cracks were found in the USTs. 3.The USTs were found to have proper roundness. Calculations are presented in Appendix B. All liner repairs were in good condition and provided adequate means to repair the fuel tanks. Additionally, a precision test was performed on the tanks, and the USTs passed. If you have any questions please contact the undersigned inspector, Bo Bowman at (720) 653-0213. Sincerely, CGRS, Inc. Rudolph Bowman Jr., Tank Inspector!!! API 653, 60073, STI SP-001, 40310 Colorado Professional Engineer License: 49192 FIGURE Site Map SITE LOCATION DATE:REVIEW: PROJECT:DRAFT: 9/8/24 28700 7006 S. 2000 E. COTTONWOOD HEIGHTS, UT 84121 JACKSON ENERGY-COTTONWOOD HEIGHTS FIGURE 1 - SITE LOCATION SJL01000 2000 SCALE IN FEET BB DATE:REVIEW: PROJECT:DRAFT: 9/8/24 28700 7006 S. 2000 E. COTTONWOOD HEIGHTS, UT 84121 JACKSON ENERGY-COTTONWOOD HEIGHTS FIGURE 2 - SITE DETAILS SJL05101520 SCALE IN FEET UST-2 RUL BB UST-3 RUL UST-1 PRE FORT UNION BLV S. H I G H L A N D D R APPENDIX A Photo Log 1 | Page Jacksons Cottonwood Heights | Octobere-2024| Photo Log UST tank tops with box shoring Installed man-way access hole in UST-2 UST Bulk Head Pitting UST Floor prior to blast UST Roof prior to blast 2 | Page Jacksons Cottonwood Heights | Octobere-2024| Photo Log UST-2 Dry Film Thickness Readings UST-2 after lining UST-3 after lining UST-1 after lining Pinholes found from curing process (patched holidays) Site cleaned up ready for backfill and concrete END OF PHOTOS APPENDIX B Calculations CGRS, Inc.PROJECT TITLE: Cottonwood Lining Inspector AST 1301 Academy Ct.Location: 40310 Fort Collins, CO Prepared by: Bo Bowman Date:9/15/24 STI SP-001 Reviewed by Bo Bowman API 653 - 60073 Date Tank Size Length (ft) Dia. (ft) Material Thickness Unit Wt.Moist (ft)lb./ft^3 % Concrete 0.75 150 <20 concrete Base soil 3.5 100 <20 pea gravel Native 0 0 <20 Coarse gravel not compacted. Tank (top)4.25 120 Native soil moist range 100 to 130 Tank (Mid)8.87 120 Tank (ft.)13.50 120 Gravel drainage: Well drained is most conservative case. No buoyancy correction. A.) Soil Loads lb./ft^2 psi Cumulative (psi) Concrete 112.5 0.78 0.78 Compacted 350 2.43 3.21 Native 0 0.00 3.21 Same point as top of tank Tank (top)510 3.54 3.21 Tank (Mid)555 3.85 3.98 Passive soil Ka =0.2 Tank (ft.)555 3.85 4.75 B.) Induced Loads H20 Fuel Truck Non compacted. 6K,8K gal Split 60048 lbs.Assume 32K to 40K 32,000 lbs. Tier contact area 2-tiers 400 (in^2)Wheel size 0.83333 1.67 ft Load per wheel set 80 psi back wheels z/b chart Dp/q Effective Load b= contact area 1.67 Tank (top)2.55 0.07 2.8 z= depth of interest Tank (Mid)5.32421875 0.015 1.2 Note: Concrete reduces Tank (ft.)8.0984375 too deep for influence Horizontal load by 50% C.) Effective Stress on UST Soil psi H-20 Psi Effective Total stress Tank (top)3.21 2.8 6.01 psi Tank (Mid)3.98 1 5.18 psi Tank (ft.)4.75 0 4.75 psi 7006 S 2000 E, Cottonwood Heights, UT 84121 Client Jacksons 24.00 Volume 12,055 gal 9.25 Content UST-1 Premium CGRS, Inc.PROJECT TITLE: Cottonwood Lining Inspector AST 1301 Academy Court Location: 40310 Fort Collins, CO Prepared by: Bo Bowman Date:9/15/24 STI SP-001 Reviewed by Bo Bowman API 653 - 60073 Date pg. 3 of 3 Tank Size Length (ft)24.00 Volume 12,055 gal L (in)288 Dia. (ft)9.25 Content Radius (in)55.484375 Tank is double walled steel / fiberglass Note: Length to center wall UL-58 Roark Formula UL-58 UST Design Thickness. Safety Factor 2 Single wall analysis Es A36 Steel 29500000 psi n =0.287 Ave. Tank shell thickness Steel thickness in 0.203 in 2nd wall thickness in 0.25 in Equivalent str. FactorRatio steel to steel 0.25 Extra thickness 0.102 in Equivalent thicknessin 0.352 Tank will Hold 184.070005 1.294 0.000040 15.63 psi O.K.> max pressure Max Soil Pressure 4.75 psi chose max pressure Max Load Pressure 6.01 psi Length to diameter ratio no more than 6. 7 CCR 1101-14 "Rule of Thumb" shell based on tank diameter 0.25"Min 90"0.25 Design Bulk Head Thickness 0.25"Min 90"0.25 Design Inspection (7 CCR 1101)(in) UT 75% original design thickness 0.1875 Max Thickness 0.247 Thickness at deepest pit 0.125 61%Remaining Min Thickness 0.189 O.K.Not extended over large area. All pits < 50% patched with hydraulic cement Ave Thickness 0.204 Ave thickness used as pitting was spread. Current State:Est. State 5-yrs: Corrosion rate 0.000 inch/year Five Year Timeline Year Installed 1989 Est future thickness 0.202 in O.K. Current Year 2024 Time 35 years Tank is Double wall Current steel thickness Outer Shell Est 0.05 in fiberglass adds extra safety Jacksons 7006 S 2000 E, Cottonwood Heights, UT 84121 Client UST-1 premium Unleaded CGRS, Inc.PROJECT TITLE: Cottonwood Lining Inspector AST 1301 Academy Ct.Location: 40310 Fort Collins, CO Prepared by: Bo Bowman Date:9/15/24 STI SP-001 Reviewed by Bo Bowman API 653 - 60073 Date Tank Size Length (ft) Dia. (ft) Material Thickness Unit Wt.Moist (ft)lb./ft^3 % Concrete 0.75 150 <20 concrete Base soil 3.5 100 <20 pea gravel Native 0 0 <20 Coarse gravel not compacted. Tank (top)4.25 120 Native soil moist range 100 to 130 Tank (Mid)8.87 120 Tank (ft.)13.50 120 Gravel drainage: Well drained is most conservative case. No buoyancy correction. A.) Soil Loads lb./ft^2 psi Cumulative (psi) Concrete 112.5 0.78 0.78 Compacted 350 2.43 3.21 Native 0 0.00 3.21 Same point as top of tank Tank (top)510 3.54 3.21 Tank (Mid)555 3.85 3.98 Passive soil Ka =0.2 Tank (ft.)555 3.85 4.75 B.) Induced Loads H20 Fuel Truck Non compacted. 6K,8K gal Split 60048 lbs.Assume 32K to 40K 32,000 lbs. Tier contact area 2-tiers 400 (in^2)Wheel size 0.83333 1.67 ft Load per wheel set 80 psi back wheels z/b chart Dp/q Effective Load b= contact area 1.67 Tank (top)2.55 0.07 2.8 z= depth of interest Tank (Mid)5.32421875 0.015 1.2 Note: Concrete reduces Tank (ft.)8.0984375 too deep for influence Horizontal load by 50% C.) Effective Stress on UST Soil psi H-20 Psi Effective Total stress Tank (top)3.21 2.8 6.01 psi Tank (Mid)3.98 1 5.18 psi Tank (ft.)4.75 0 4.75 psi 7006 S 2000 E, Cottonwood Heights, UT 84121 Client Jacksons 24.00 Volume 12,055 gal 9.25 Content UST-2 Unleaded CGRS, Inc.PROJECT TITLE: Cottonwood Lining Inspector AST 1301 Academy Court Location: 40310 Fort Collins, CO Prepared by: Bo Bowman Date:9/15/24 STI SP-001 Reviewed by Bo Bowman API 653 - 60073 Date pg. 3 of 3 Tank Size Length (ft)24.00 Volume 12,055 gal L (in)288 Dia. (ft)9.25 Content Radius (in)55.484375 Tank is double walled steel / fiberglass Note: Length to center wall UL-58 Roark Formula UL-58 UST Design Thickness. Safety Factor 2 Single wall analysis Es A36 Steel 29500000 psi n =0.287 Ave. Tank shell thickness Steel thickness in 0.215 in 2nd wall thickness in 0.25 in Equivalent str. FactorRatio steel to steel 0.25 Extra thickness 0.108 in Equivalent thicknessin 0.358 Tank will Hold 190.407678 1.294 0.000042 16.30 psi O.K.> max pressure Max Soil Pressure 4.75 psi chose max pressure Max Load Pressure 6.01 psi Length to diameter ratio no more than 6. 7 CCR 1101-14 "Rule of Thumb" shell based on tank diameter 0.25"Min 90"0.25 Design Bulk Head Thickness 0.25"Min 90"0.25 Design Inspection (7 CCR 1101)(in) UT 75% original design thickness 0.1875 Max Thickness 0.247 Thickness at deepest pit 0.125 61%Remaining Min Thickness 0.189 O.K.Not extended over large area. All pits < 50% patched with hydraulic cement Ave Thickness 0.204 Ave thickness used as pitting was spread. Current State:Est. State 5-yrs: Corrosion rate 0.000 inch/year Five Year Timeline Year Installed 1989 Est future thickness 0.215 in O.K. Current Year 2024 Time 35 years Tank is Double wall Current steel thickness Outer Shell Est 0.05 in fiberglass adds extra safety Jacksons 7006 S 2000 E, Cottonwood Heights, UT 84121 Client UST-2 Unleaded CGRS, Inc.PROJECT TITLE: Cottonwood Lining Inspector AST 1301 Academy Ct.Location: 40310 Fort Collins, CO Prepared by: Bo Bowman Date:9/15/24 STI SP-001 Reviewed by Bo Bowman API 653 - 60073 Date Tank Size Length (ft) Dia. (ft) Material Thickness Unit Wt.Moist (ft)lb./ft^3 % Concrete 0.75 150 <20 concrete Base soil 3.5 100 <20 pea gravel Native 0 0 <20 Coarse gravel not compacted. Tank (top)4.25 120 Native soil moist range 100 to 130 Tank (Mid)8.87 120 Tank (ft.)13.50 120 Gravel drainage: Well drained is most conservative case. No buoyancy correction. A.) Soil Loads lb./ft^2 psi Cumulative (psi) Concrete 112.5 0.78 0.78 Compacted 350 2.43 3.21 Native 0 0.00 3.21 Same point as top of tank Tank (top)510 3.54 3.21 Tank (Mid)555 3.85 3.98 Passive soil Ka =0.2 Tank (ft.)555 3.85 4.75 B.) Induced Loads H20 Fuel Truck Non compacted. 6K,8K gal Split 60048 lbs.Assume 32K to 40K 32,000 lbs. Tier contact area 2-tiers 400 (in^2)Wheel size 0.83333 1.67 ft Load per wheel set 80 psi back wheels z/b chart Dp/q Effective Load b= contact area 1.67 Tank (top)2.55 0.07 2.8 z= depth of interest Tank (Mid)5.32421875 0.015 1.2 Note: Concrete reduces Tank (ft.)8.0984375 too deep for influence Horizontal load by 50% C.) Effective Stress on UST Soil psi H-20 Psi Effective Total stress Tank (top)3.21 2.8 6.01 psi Tank (Mid)3.98 1 5.18 psi Tank (ft.)4.75 0 4.75 psi 7006 S 2000 E, Cottonwood Heights, UT 84121 Client Jacksons 24.00 Volume 12,055 gal 9.25 Content UST-3 Unleaded CGRS, Inc.PROJECT TITLE: Cottonwood Lining Inspector AST 1301 Academy Court Location: 40310 Fort Collins, CO Prepared by: Bo Bowman Date:9/15/24 STI SP-001 Reviewed by Bo Bowman API 653 - 60073 Date pg. 3 of 3 Tank Size Length (ft)24.00 Volume 12,055 gal L (in)288 Dia. (ft)9.25 Content Radius (in)55.484375 Tank is double walled steel / fiberglass Note: Length to center wall UL-58 Roark Formula UL-58 UST Design Thickness. Safety Factor 2 Single wall analysis Es A36 Steel 29500000 psi n =0.287 Ave. Tank shell thickness Steel thickness in 0.203 in 2nd wall thickness in 0.25 in Equivalent str. FactorRatio steel to steel 0.25 Extra thickness 0.102 in Equivalent thicknessin 0.352 Tank will Hold 184.070005 1.294 0.000040 15.63 psi O.K.> max pressure Max Soil Pressure 4.75 psi chose max pressure Max Load Pressure 6.01 psi Length to diameter ratio no more than 6. 7 CCR 1101-14 "Rule of Thumb" shell based on tank diameter 0.25"Min 90"0.25 Design Bulk Head Thickness 0.25"Min 90"0.25 Design Inspection (7 CCR 1101)(in) UT 75% original design thickness 0.1875 Max Thickness 0.247 Thickness at deepest pit 0.125 61%Remaining Min Thickness 0.189 O.K.Not extended over large area. All pits < 50% patched with hydraulic cement Ave Thickness 0.204 Ave thickness used as pitting was spread. Current State:Est. State 5-yrs: Corrosion rate 0.000 inch/year Five Year Timeline Year Installed 1989 Est future thickness 0.202 in O.K. Current Year 2024 Time 35 years Tank is Double wall Current steel thickness Outer Shell Est 0.05 in fiberglass adds extra safety Jacksons 7006 S 2000 E, Cottonwood Heights, UT 84121 Client UST-3 Unleaded Roundness Data Analysis Est Age 35 years Client Jackson Energy Est design thicknessDouble wall Location Cottonwood Heights, UT Ave diameter 110.508 Ave diameter110.918 Ave diameter110.617 UST-1 UST-2 UST-3 Angle 1 2 1 2 Angle 1 2 1 2 Angle 1 2 1 2 90 o 110.969 110.781 0.4%0.2%90 o 110.625 110.969 -0.3%0.0%90 o 110.969 110.563 0.3%0.0% 135 o 110.063 110.688 -0.4%0.2%135 o 110.688 111.000 -0.2%0.1%135 o 110.688 110.000 0.1%-0.6% 180 o 110.125 110.750 -0.3%0.2%180 o 110.969 111.563 0.0%0.6%180 o 110.625 110.781 0.0%0.1% 225 o 110.063 110.625 -0.4%0.1%225 o 110.750 110.781 -0.2%-0.1%225 o 110.688 110.625 0.1%0.0% 90 o 225 o 135 o 180 o Measurement (in)Measurement (in)Measurement (in) Tank Interstitial Test Facility Information Name:Cottonwood Heights Certification/Inspection #:54549 Address:7006 S. 2000 E., Cottonwood Heights, UT, 84121 State ID: Phone Number:Form Completed By:Ray Simms Date:09/10/2024 Tank Information 1.Tank #:T1 PUL T3 MID T2 RUL 2.Tank Facility ID T1 PUL T3 MID T2 RUL 3.Product:Premium Unleaded Plus Unleaded 4.Tank Capacity* (gallons):12022 12022 12022 5.Tank Material:DW Lined Steel DW Lined Steel DW Lined Steel 6.Initial vacuum reading (inHg)5 5 5 7.Final vacuum reading (inHg)5 5 5 8.Test Duration (hh:mm)01:00 01:00 01:00 9.Level Change 0.00 0.00 0.00 10.Is the annular space dry after the test?Yes Yes Yes 11.Test Result Pass Pass Pass Comments Operator Certification Contractor Printed Name:Ray Simms Contractor Signature: