Attachment K.1 - Barksdale-Fac 6350 RU2 (Tank 2)-FINAL-2011.pdf

Report No.: Barksdale 6350-2 File No.: 46

INDEX

1.0 EXECUTIVE SUMMARY

2.0 SUITABILITY FOR SERVICE STATEMENT

3.0 TANK INSPECTION SUMMARY SHEET

4.0 TANK HISTORY

5.0 METHODOLOGY

6.0 FINDINGS

6.1 CONTAINMENT

6.2 FOUNDATION

6.3 CATHODIC PROTECTION

6.4 SHELL

6.5 SHELL NOZZLES AND APPURTENANCES

6.6 STAIRS, PLATFORMS, AND GRATINGS

6.7 FIXED ROOF AND APPURTENANCES

6.8 FLOATING ROOF AND APPURTENANCES

6.9 TANK BOTTOM AND APPURTENANCES

6.10 LEVEL DETECTION AND OVERFILL PROTECTION

7.0 RECOMMENDATIONS

1.1 MANDATORY REPAIRS

1.2 NEAR FUTURE REPAIRS AND RECOMMENDATIONS

1.3 LONG-TERM REPAIRS AND RECOMMENDATIONS

8.0 APPENDICES

8.1 APPENDIX A ENGINEERING CALCULATIONS

8.2 APPENDIX B ULTRASONIC THICKNESS MEASUREMENTS

8.3 APPENDIX C API-653 INSPECTION CHECKLIST

8.4 APPENDIX D INSPECTION DRAWINGS

8.5 APPENDIX E INSPECTION PHOTOS

8.6 APPENDIX F REFERENCES

1.0 EXECUTIVE SUMMARY

This report provides an engineering evaluation of JP-8 Storage Tank 6350-2, located at Barksdale Air Force Base in Bossier City, Louisiana. The report summarizes the results of an API 653 Out-of-Service inspection conducted by Integrity Consulting Services, LLC. The inspection was completed on November 14th, 2011. All available resources were utilized to gather as much information as possible in order to compile a thorough inspection report. However, there were some details which were unknown or had to be assumed. Integrity Consulting Services strives to provide as much information as possible to insure safe and reliable tank operations.

API STANDARD 653

recommends that this document containing valuable historical information be retained for the life of the tank.

2.0 SUITABILITY FOR SERVICE STATEMENT

An API Standard 653 Out-of-Service inspection of JP-8 Storage Tank 6350-2, located at Barksdale Air Force Base in Bossier City, Louisiana, was completed on November 14th, 2011. This inspection was conducted to collect data in order to evaluate the mechanical integrity and fitness for continued service of the tank.

Based on current conditions found during the tank inspection, it is determined that the tank is suitable for continued service. Any changes to the tank operation may influence the suitability for service and should only be made under the direction of the Authorized Inspector and a Professional Engineer.

A brief tank inspection summary can be found on the following pages. This tank inspection summary will provide a description of the tank, the type inspection performed, and other parameters regarding the tank.

Please refer to the FINDINGS and RECOMMENDATIONS sections of this report for any discrepancies that were identified during the course of this inspection, and recommendations for their correction.

Required next inspections per API-653 or DoD guidelines:

External (In-Service): 11/14/2016 Internal (Out-of-Service): 11/14/2021 UT Thickness: 11/14/2021

Richard A. Laton Jr.

Robert and Company API-653 Inspector

Certification Number 2193

3.0 TANK INSPECTION SUMMARY SHEET

Tank Number 6350-2 Tank Owner US Air Force Location Bossier City, LA Inspection Dates 14 November, 2011 Type of Inspection API 653 Out-of-Service inspection, UT ,MFE survey Name of Prime Contractor Robert and Company Name of Inspection Company Integrity Consulting Services Inspector Name, Certification Number and Expiration

Richard A. Laton Jr. API 653 #2193 (exp. 4/30/12)

Last Inspection Date and Type August 11, 2004 by Environmental Technologies, Incorporated

Type of Tank Vertical AST Tank Manufacturer Woods Tank Inc.

Year Tank Manufactured 1998 Design Standard API-650, 8 th Ed.

Design Pressure and Temperature Atmospheric @ 200°F Product JP-8 Jet Fuel Tank Dimensions 32’9.5” Ø x 39’3” shell height

Gross Storage Capacity 248,856 gallons

Nominal Storage Capacity 215,996 gallons to High Level 220,437 gallons to High-High Level 226,960 gallons to vent overflow

Safe Fill Height 34’ – 11 ½”” to High-High Level Foundation Configuration Concrete Ringwall

Leak Detection Under tank bottom membrane liner with two 1 ½” leak detection tell-tale fittings

Cathodic Protection Yes, previous cathodic protection survey performed during October 2011

Tank Bottom Configuration 10 lap welded floor plates, 5/16” nominal thickness, sloped to 36” Ø center sump (1:20 slope)

Tank Shell Configuration

Bottom course = 8’ height Second course = 8’ height Third course = 8’ height Fourth course = 8’ height Fifth course = 7’ height All course are ¼” nominal thickness

Fixed Roof Configuration 10 lap welded roof plates, ¼” nominal thickness, cone-up configuration

Floating Pan/Roof PETREX type aluminum, closed honeycomb cell floating pan

Type Seal Primary and secondary wiper seal – primary seal failed, secondary seal OK

Stilling Wells (Size and Application) 8” gauging well for manual tank gauging and 8” gauging well for ATG probe

Tank Vents Four rim vents for floating pan, four roof periphery vents and one roof center vent

Stairs/Ladders Spiral staircase (external) for access to tank top.

Vertical ladder from tank top to the floor

Manholes Two 36” manways on shell; one 36” manway on fixed roof

Interior Coating and Date Entire interior surfaces coated with an unknown coating system

Exterior Coating and Date Entire exterior surfaces coated with an unknown coating system

Level Gauging

ITT Barton electronic ATG (model TS10-1319A, serial number 2842) Shand & Jurs mechanical ATG (model 92021- 31050100-98051007)

Overfill Protection/Level Alarm High-high and high level alarm mounted on shell

Internal Piping 14” issue, 10” receipt, 4” pump out and ¾” water draw

Strapping Tables (Tank Re-Calibration to 1/16”) Tank strapping chart ( 1/16” increments) performed on September 9, 1998 by Saybolt LP

Water Draw-Off System PRT tank installed with dedicated pump

Secondary Containment Concrete dike with flat bottom and vertical walls with installed coating system

Fire Protection Three external fire hydrants GPS Location 32°31’5.9” N; 93°39’49.3” W

Can Tank Return to Service? (If no, explain) No, see tank recommendations contained within this report.

Deficiencies Identified as Mandatory Repairs See section 7.1 of this report Deficiencies Identified as Recommended Repairs See section 7.2 of this report Deficiencies Recommended as Long Term Repairs See section 7.3 of this report Next External Visual Inspection Date 11/14/2016 Next Internal Visual Inspection Date 11/14/2021 Next Ultrasonic Thickness Inspection Date 11/14/2021 Upgrades/Repairs Made at Time of Inspection None

4.0 TANK HISTORY

1998 – Tank manufactured by Woods Tank Inc.

July 2004 – API 653 Out-of-Service inspection performed by Austin

Brockenbrough and Assoc. and Environmental Technologies, Inc.

5.0 METHODOLOGY

An API Standard 653 In-Service inspection was performed on Tank 6350-2, located at Barksdale Air Force Base. Inspections performed during this inspection cycle included the following:

External visual inspection in accordance with API-653 Appendix C checklist Ultrasonic thickness examination on shell, fixed roof and nozzles Shell settlement survey

6.0 FINDINGS

6.1 CONTAINMENT DIKE

Tank 6350-2 is in a containment dike with its sister tank. There is a dividing wall between the two tanks. The containment dike is of adequate size to accommodate both tank contents + 10% freeboard in case of tank or component failure. There are stairs which can be used to access the containment area on the south wall.

The condition of the containment dike is good with only very minor surface cracks noted on the walls and floor. There have been several repairs made at the dike floor and walls to seal previously discovered cracks. The sealant applied is in good condition with no cracking or defects noted. There are ≈ 250-300 linear feet of cracking which should be repaired to ensure a leak proof containment.

There is a drainage sump in the southwest corner of the dike floor which can be opened to discharge tank contents into an oil/water separator located outside the containment dike. Once the water has been processed inside the separator, the water is then transferred to a drainage flume where environmental water sampling occurs monthly.

Piping enters through the far west containment dike wall (the wall near tank 6350-1). Piping is installed with link seals to prevent leakage outside of the dike wall.

6.2 FOUNDATION

Tank 6350-2 sits on an elevated concrete ringwall (≈28-29” in height). The entire ringwall is coated. The coating is in poor condition and failed in several areas.

The tank bottom is sealed at the top side of the ringwall to prevent water from entering under the tank. The seal is a rubber sealant with a coating applied over

it. The rubber seal is in good condition, but the coating is deteriorated.

There are two tell-tale openings installed in the concrete ringwall for leak detection. Each threaded tell-tale is provided with a valve, and is capped. When opened, the drain on the west side of the tank had a large amount of clean water come from it. It was discussed with base personnel and it was decided the source of water was condensation. There was no fuel odor detected from the water.

6.3 CATHODIC PROTECTION

Tank has an impressed current cathodic protection system installed under the tank bottom.

The most recent survey of the cathodic protection system was perform October, 2011.

6.4 SHELL

The tank is a vertical, above ground storage tank constructed of five carbon steel shell courses. Tank nominal capacity is 248,856 gallons with a maximum usable capacity of 226,960 gallons. The shell is constructed of A-36 modified carbon steel plates. Each shell course is constructed of four circumferential plates. The shell course heights and nominal thicknesses are as follows:

COURSE # HEIGHT THICKNESS

1 8’ .250” 2 8’ .250” 3 8’ .250” 4 8’ .250” 5 7’ .250”

The external shell coating is in good condition with only minor isolated failures noted.

The shell is equipped with a ¼” x 2 ½” x 2 ½” rim angle at the top of the tank.

There are no wind girders installed on the shell.

The shell is straight and plumb with no peaking or banding noted.

The structural welds are serviceable with no leaks or defects noted.

The shell is equipped with four grounding points and 12 anchor bolts. Both the grounding points and anchor bolts are in good condition.

The internal shell coating is in good condition with no coating failure noted.

6.5 SHELL APPURTENANCES AND NOZZLES

Tank 6350-2 has several nozzle penetrations used for various tank functions.

Nozzles provided on this tank shell are as follows:

Two 36” manways located on the first shell course 10” receipt line 14” issue line 3/4” water draw with a dedicated product recovery tank 4” pump out There are several 1” threaded couplings on the shell, four of which are capped. Two are used for high and high-high level alarms.

All tank nozzles are provided with adequate reinforcing pads. The reinforcing pads meet all API-650 requirements for weld spacing. There are weepholes installed as required. The weepholes on the reference manway (the one with the nameplate installed) and the 4” pump out line are plugged with a bolt.

The reference manway cover flange is warped. It is difficult to establish a good seal at the manway. The manway bolts have to be torqued extremely tight to prevent leakage at the manway.

The receipt line is not equipped with a hydraulically operated control valve set to close when the tank contents reaches 95% capacity.

All internal piping is adequately supported on the floor. None of the support pads are welded directly to the floor, but they are restricted from horizontal movement.

Structurally, the supports appear to be adequate, but when the tank was being cleaned, it was noted that there was discolored water being washed out from under the supports. It is believed that this may be the start of coating failure which could eventually cause erosion/corrosion on the product-side of the floor plates beneath the piping support pads.

The internal piping is connected at the shell penetration with Victaulic couplings at the issue, receipt and pump out lines. The water draw line is connected with a threaded union. This is not recommended.

6.6 STAIRS, PLATFORMS AND GRATINGS

Tank 6350-2 has a spiral staircase ascending to the top of the tank. Treads and handrails are of painted carbon steel and in good condition. Treads are not welded directly to the shell, but attached to a plate which is attached to the shell by clips.

There is an internal, vertical ladder extending from the tank bottom to the 36” roof manway.

6.7 FIXED ROOF AND APPURTENANCES

Tank 6350-2 is provided with a fixed external roof constructed of ten lap welded plates, each with a nominal thickness of .250”.

The external roof is provided with the following appurtenances:

36” manway with an 8” stilling well for tank gauging 14” nozzle with an 8” stilling well for ATG probe insertion 12” center vent 24” x 72” access hatch Four roof rim vents Handrails provided all the way around the roof perimeter

There are several areas of minor paint failure located on the roof deck. There is also an old carbon steel flange lying on the roof which is promoting paint failure.

6.8 FLOATING ROOF AND APPURTENANCES

Tank 6350-2 has a PETREX type aluminum floating pan constructed of closed honeycomb cells. The floating pan is in good condition with no defects noted.

The primary seals are in failed condition. There was a large amount of fuel found between the primary and secondary seals. The secondary seal is in serviceable condition with only one area found where the fabric has torn from the rubber wiper with a split in the wiper noted.

The floating roof is supported with seven floating legs which were pinned in the high position for tank inspection.

The floating pan has several appurtenances for tank operation including a pressure/vacuum breaker, an opening for stilling wells and the vertical ladder, an anti-rotation cable, an attachment for the Shand & Jurs visible level gauge and grounding straps. The seals around the openings for the stilling wells and ladders are failed.

6.9 TANK BOTTOM AND APPURTENANCES

The floor is constructed of ten carbon steel, lap welded plates, each with a nominal thickness of .3125”.

Bottom floor plates are lap welded backwards. As is, the fuel will not properly drain into the center sump and it’s possible that water can be trapped on the floor surface.

The supports for the floating roof legs are 12” x 12” stainless steel striker plates which are glued to the floor.

There is a 36” center sump installed in the floor where the issue, tank pump out and water draw lines all terminate.

There are several unused floor attachment clips on the floor which are potential trip hazards and serve no useful purpose.

The tank floor has cathodic protection installed. The previous cathodic protection survey, performed by the base electrical shop in October of 2011 did not reveal any defects or anomalies.

6.10 TANK LEVEL DETECTION AND OVERFILL PROTECTION

Tank 6350-2 is equipped with an ITT Barton ATG system for determining level of product in the tank. There are also high and high-high level alarms located on the shell. There is no low level alarm.

There is a Shand & Jurs visible level gauge (model number 92021-31050100- 98051007) located on the tank shell. The visible gauge is not operable. The cable attached to the aluminum floating pan does not actuate the mechanical readout on the gauge head. The cable does not pull and return freely.

7.0 RECOMMENDATIONS

7.1 MANDATORY REPAIRS

Mandatory items are repairs or changes necessary to preserve or restore the structural integrity of the tank, to comply with code or regulatory standards.

The floating roof seal must be replaced before the tank is placed back into service.

The manway cover flange should be replaced to ensure that tank leakage does not occur.

Install a hydraulically operated high level control valve which will close when tank contents reaches 95% of tank capacity. (In accordance with UFC 3-460-01)

7.2 NEAR FUTURE REPAIRS AND RECOMMENDATIONS

Near term recommendations are repairs or upgrades based on good engineering and maintenance practices.

All pipe support pads on the floor should be fully seal welded to the floor and coated to prevent erosion/corrosion from occurring under the pad.

Stainless steel striker plates on the floor for the floating legs should be replaced with steel plates full seal welded to the floor and coated. The floating pan legs should also be fitted with Teflon inserts to prevent damage to the coating. (In accordance with API STD 650 H.4.6.6)

Repair or replace the Shand & Jurs visible tank gauge.

Install a shell mounted low level alarm which is independent of the tank gauging system to switch off the issue pumps when the low level is reached. (In accordance with MIL-HDBK-1022A, Table 2, item j)

Remove plugs from weepholes to check for leakage behind repads.

7.3 LONG TERM REPAIRS AND RECOMMENDATIONS

Long term recommendations are repairs or upgrades intended to extend the service life of the tank, ensure continued compliance with code or regulatory requirements or for discretionary improvements.

The threaded couplings attached to the shell which are unused should be removed. As is, they are potential sources of leakage.

The attached clips on the floor are unused. As a safety issue, they are trip hazards. From an engineering perspective, they are stress risers which could potentially weaken the floor. Because they are welded near the chime weld, they should be removed.

Ensure that the reverse welded lap welds on the floor is not hindering the tank operations. It was discussed that because these tanks were only used for truck receiving operations, and not for product issue directly to aircraft, this is not considered to be a major issue at this time.

All areas of coating failure on the roof deck shall be cleaned and treated to remove all active corrosion and the coating shall be replaced with a coating system similar to what is currently present.

Issue piping should be shortened to a length approximately half the distance from the shell to the sump.

APPENDIX A

Engineering Calculations

1) Shell Minimum Thickness and Remaining Life Calculations

2) Roof Minimum Thickness and Remaining Life Calculations

3) Floor Minimum Thickness and Remaining Life Calculations

4) Nozzle Minimum Thickness and Remaining Life Calculations

5) Shell Out-of-Plane Settlement Survey Calculations

API-653 ATMOSPHERIC STORAGE TANK SHELL EVALUATION

Minimum Thickness and Remaining Life Calculations

File No. Report No. Client Inspector Tank No. Date

46 Barksdale 6350-2 Barksdale AFB Richard A. Laton Jr. 6350-2 11/14/2011

SHELL MINIMUM THICKNESS CALCULATIONS

tmin = 2.6D(H-1)G

SE

Where:

H = Height above the bottom of the course of study to the maximum liquid level height of the product, in feet. For corroded or pitted areas, H = the height from the bottom of the corroded or pitted area to the maximum liquid level height of the product, in feet.

tmin = Calculated minimum acceptable shell thickness, in inches (must be greater than 0.1 inch for any course). The minimum acceptable shell thickness allowed by API-653 for tank size, in inches or an alternate tmin based on low pressure calculations (internal and/or external pressures) or nominal thickness minus design corrosion allowance.

D = Nominal diameter of tank, in feet.

G = Highest specific gravity of the contents (including test water if tank will, or may, be tested in the future).

S = Maximum allowable stress, in psi. For welded tanks; use the smaller of 0.80Y of 0.429T for bottom and second course or the smaller of 0.88Y or 0.472T for all other courses. For riveted tanks; S = 21,000 psi.

(145 MPa)

Y = Specified minimum yield strength of the plate, in psi; use 30,000 psi (200 MPa) if not known (N/A for riveted tanks).

T = The smaller of the specified minimum tensile strength of the plate or 80k psi (550 MPa); use 55,000 psi (380 MPa) if not known (N/A for riveted tanks).

E = Original joint efficiency for the tank. For welded tanks; use API-653, Table 4-2 ; use E = 1.0 when evaluating the retirement thickness in a corroded plate, when away from welds or joints by at least the greater of one inch (250 mm) or twice the plate thickness. For riveted tanks; use E = 1.0 for shell plates greater than 6 inches (150 mm) away from rivets; use the value of E from API-653 Table 4-3 when within 6 inches (150 mm) of rivets.

D (ft) 32.81 G 0.84 E 1 Fill Ht (ft) 36.09

Course Material Crs H (ft) H (ft) S (psi) tmin (in)

Course 1 A36/M 8.000 36.09 24900 0.104

Course 2 A36/M 8.000 28.09 24900 0.100

Course 3 A36/M 8.000 20.09 27400 0.100

Course 4 A36/M 8.000 12.09 27400 0.100

Course 5 A36/M 7.000 4.09 27400 0.100

API-653 ATMOSPHERIC STORAGE TANK SHELL EVALUATION

Minimum Thickness and Remaining Life Calculations

SHELL REMAINING LIFE CALCULATIONS

Ca = tact-tmin = Remaining Corrosion Allowance (inches)

Cr = tprev-tact / Y = Corrosion Rate (inches per year)

RL = Ca / Cr = Remaining Life (years)

Y = 13 =Tank age (years)

Where:

Ca = Remaining corrosion allowance of the shell course under consideration, in inches.

Cr = Corrosion rate of the shell course under consideration, in inches per year.

tact = Minimum thickness measurement of the shell course under consideration, as recorded at the time of inspection, in inches.

tmin = minimum required thickness of shell course, at the maximum allowable fill height, in inches.

tprev = previous thickness measurement of shell course under consideration, as recorded at last inspection or nominal thickness if no previous thickness measurements, in inches.

RL = Estimated remaining life of the shell course under consideration, in years.

Y = Time span between thickness readings or age of the tank if nominal thickness is used for tprev, in years.

Course tprev tact tmin Ca Cr RL

Course 1 0.250 0.239 0.104 0.135 0.0008 >20

Course2 0.250 0.240 0.100 0.140 0.0008 >20

Course 3 0.250 0.244 0.100 0.144 0.0005 >20

Course 4 0.250 0.249 0.100 0.149 0.0001 >20

Course 5 0.250 0.255 0.100 0.155 <.0001 >20

API-653 ATMOSPHERIC STORAGE TANK FIXED ROOF EVALUATION

Minimum Thickness, Remaining Life, Pressure Calculations

Where;

Ca = remaining corrosion allowance of the tank component under consideration, in inches (t act - t min)

Cr = corrosion rate of the tank component under consideration, in inches (mm) per year (t prev - t act / Y)

DCa = original design corrosion allowance of the tank component under consideration, in inches

KPa = kilopascal - (1 KPa = 1000 Pa) (1 KPa=0.146psi) unit of pressure. It is a measure of force per unit area. 1 Pascal (Pa) = 1 N/m2 = 1 J/m3 = 1 kg/(m·s2) psi = unit of measurement, (weight, in pounds, per square inch)

RL = estimated remaining life of the tank component under consideration, in years (Ca / Cr) t act = actual thickness measurement of the tank component under consideration, as recorded at the time of inspection, in inches t min = minimum required thickness of tank component, at the design MAWP at the design temperature (200°F for atm AST's), in inches (greater of psi/wt or 0.090"). Where t min calculates to greater than t prev, t prev - 0.063" t nom = design nominal thickness of tank component under consideration, in inches t prev = previous thickness measurement of the tank component under consideration, as recorded at last inspection or nominal thickness if no previous thickness measurements, in inches t yn = thickness of the tank component under consideration at the next inspection at twice the calculated corrosion rate, in inches (t act - (2*Cr*Yn) wt = weight of plate per cubic inch wc = unit of measurement, (height, in inches, of water column bearing on 1 square inch area), (27.7 wc per pound)

Y = time span between thickness readings or age of the tank component if t nom is used for t prev, in years

Yn = estimated time span to next inspection of the tank component under consideration, in years

ROOF PLATES - REMAINING LIFE

Y t prev t act t min Cr Ca RL

13 0.25 0.241 0.09 0.0007 0.151 >20

ROOF MAXIMUM ALLOWABLE INTERNAL PRESSURE

Material wt (psi) Yn t yn psi oz Wc KPa

Carbon Steel 0.2883 5 0.234 0.067 1.080 1.869 0.466

API-653 ATMOSPHERIC STORAGE TANK FLOOR EVALUATION

MINIMUM REMAINING THICKNESS (MRT) CALCULATIONS

Liner CP Protec.

50mil Liner

Leak Det. Ca Shell tmin Shell tnom

D H

Yes Yes Yes Yes 0.000 0.104 0.250 32.81 39.25

Where;

Ca = corrosion allowance, in inches.

MRT = minimum remaining thickness at the end of interval Or, in inches. This value must meet the requirements of Table 4.4 and sections 4.4.5.4 and 4.4.6.

Or = In-service interval of operation (years to next internal inspection) not to exceed that allowed by 6.4.2.

RTbc = minimum remaining thickness from bottom side corrosion after repairs, in inches.

RTip = minimum remaining thickness from internal corrosion after repairs, in inches.

StPr = maximum rate of corrosion not repaired on the top side. StPr = 0 for coated areas of the bottom.

The expected life of the floor must equal or exceed Or to use StPr = 0.

tmin = minimum allowable thickness in accordance with requirements of Table 4.4 and sections 4.4.5.4 and 4.4.6, in inches.

to = original (nominal) thickness of floor plate under consideration, in inches.

UPr = maximum rate of corrosion on the bottom side, in inches. To calculate the corrosion rate, use the minimum remaining thickness after repairs. Assume a linear rate based on the age of the tank.

UPr = 0 for areas that have effective cathodic protection.

D = nominal diameter of tank, in ft.

H =Height, in feet, from the bottom of the 1st shell course to the maximum allowable fill height.

GENERAL PLATES - AFTER INSPECTION / REPAIRS

Age to RTbc RTip UPr StPr Or MRT tmin Results

13 0.3125 0.302 0.302 0.0008 .0008 20 0.288 0.050 ACCEPTABLE

PLATES IN CRITICAL ZONE (3") - AFTER INSPECTION / REPAIRS

Age to RTbc RTip UPr StPr Or MRT tmin Results

13 0.3125 0.304 0.304 0.0007 0.0007 20 0.291 0.100 ACCEPTABLE

API-653 STORAGE TANK NOZZLE EVALUATION

Nozzle Remaining Life Calculations

Minimum Thickness Determinations:

a) The following pipe minimum thicknesses are based on the current in- house engineering standards, which take into consideration, pressures, structural integrity and localized corrosion allowance.

Size <=2" 3" 4" 6" 8" 10" 12" >12" t min 0.070 0.100 0.100 0.125 0.156 0.156 0.188 0.188

Nozzle Remaining Life Calculations:

CML Age Description Size t prev t act t min Ca Cr RL

N1 13 Reference manway 36" 0.500 0.496 0.188 0.308 0.0003 >20

N2 13 Receipt 10" 0.594 0.566 0.156 0.410 0.0022 >20

N3 13 Issue 14" 0.594 0.560 0.188 0.372 0.0026 >20

N4 13 Pump out 4" 0.337 0.337 0.100 0.237 <.0001 >20

N5 13 Manway 36" 0.500 0.502 0.188 0.314 <.0001 >20

N6 13 Manway 36" 0.188 0.187 0.090 0.097 0.0001 >20

N7 13 Gauge well 14" 0.500 0.500 0.188 0.312 <.0001 >20

N8 13 Vent 12" 0.406 0.408 0.188 0.220 <.0001 >20

N/A - No Access

API-653 APPENDIX B SETTLEMENT EVALUATION

Rigid Body Planar Tilt Survey

D= Diameter of tank U = Measured out-of-plane settlement in relation to a cosine curve, in feet S = Deflection, in feet, (out-of-plane distortion)

L = Arc length between measurement points, in feet Y = Yield strength, in pounds per square inch (psi) E - Young's modulus, in pounds per square inch (psi) H = Tank height, in feet

D L Y E H S-Max permissible

32.81 12.884 36000 29000000 39.25 +/- 0.0289 ft +/- 0.3465 in

Feet Inches U S Results

Point 1 1 2.750 0.0053 0.0072 SAT High point 1.260 ft

Point 2 1 2.875 -0.0006 0.0031 SAT 15.125 in

Point 3 1 3.000 -0.0009 0.0067 SAT

Point 4 1 3.125 -0.0021 0.0055 SAT Low point 1.229 ft

Point 5 1 3.125 0.0004 0.0037 SAT 14.750 in

Point 6 1 3.000 0.0054 0.0073 SAT

Point 7 1 3.000 -0.0044 0.0042 SAT Planar Tilt 0.031 ft

Point 8 1 2.875 -0.0031 0.0049 SAT 0.375 in

SAT-Satisfactory; UNSAT-Unsatisfactory

API-653 APPENDIX B SETTLEMENT EVALUATION

Rigid Body Planar Tilt Survey

1.229

1.240

1.250

1.260 1.260

1.250 1.250

1.240

1.210

1.215

1.220

1.225

1.230

1.235

1.240

1.245

1.250

1.255

1.260

1.265

1 2 3 4 5 6 7 8

Measured Cosine approximation

APPENDIX B

Thickness Measurement Record

1) Shell UT Measurements

2) Roof UT Measurements

3) Floor UT Measurements

4) Nozzle UT Measurements

API-653 STORAGE TANK EVALUATION

AST Component Inspection Data

Component Thickness Measurements (in inches)

Note: Measurements at stairs taken above and below welds and at 1’ increments

CML Component Location tml-1 tml-2 tml-3 tml-4 tml-5 tml-6 tml-7 tml-8 tml-9 Minimum

1 Course 1 Plt1 0.250 0.266 0.256 0.245 0.246 0.244 0.271 0.259 0.246 0.244

2 Course 1 Plt2 0.254 0.245 0.248 0.246 0.260 0.248 0.251 0.251 0.250 0.245

3 Course 1 Plt3 0.258 0.267 0.244 0.243 0.240 0.246 0.259 0.241 0.244 0.240

4 Course 1 Plt4 0.251 0.261 0.258 0.245 0.246 0.239 0.251 0.248 0.254 0.239

5 Course 2 At Stairs 0.257 0.258 0.240 0.257 0.247 0.247 0.256 0.259 0.251 0.240

6 Course 3 At Stairs 0.251 0.259 0.265 0.262 0.247 0.247 0.261 0.245 0.244 0.244

7 Course 4 At Stairs 0.260 0.262 0.259 0.262 0.259 0.264 0.260 0.264 0.249 0.249

8 Course 5 At Stairs 0.256 0.263 0.265 0.268 0.261 0.260 0.255 0.262 0.255

9 Roof Plt1 0.259 0.260 0.270 0.261 0.260 0.259

10 Roof Plt2 0.257 0.261 0.252 0.255 0.251 0.251

11 Roof Plt3 0.255 0.251 0.250 0.255 0.253 0.250

12 Roof Plt4 0.257 0.260 0.258 0.261 0.254 0.254

13 Roof Plt5 0.253 0.260 0.255 0.258 0.257 0.253

14 Roof Plt6 0.254 0.253 0.254 0.261 0.256 0.253

15 Roof Plt7 0.249 0.250 0.250 0.255 0.249 0.249

16 Roof Plt8 0.244 0.253 0.241 0.254 0.260 0.241

17 Roof Plt9 0.250 0.244 0.243 0.253 0.248 0.243

18 Roof Plt10 0.249 0.249 0.250 0.249 0.245 0.245

19 Floor Plt1 0.318 0.307 0.320 0.312 0.309 0.307

20 Floor Plt2 0.323 0.331 0.322 0.323 0.325 0.322

21 Floor Plt3 0.318 0.309 0.310 0.322 0.331 0.309

22 Floor Plt4 0.328 0.323 0.331 0.342 0.340 0.323

23 Floor Plt5 0.331 0.339 0.336 0.337 0.340 0.331

24 Floor Plt6 0.310 0.314 0.319 0.321 0.327 0.310

25 Floor Plt7 0.319 0.334 0.318 0.323 0.328 0.318

26 Floor Plt8 0.318 0.312 0.309 0.324 0.328 0.309

27 Floor Plt9 0.313 0.314 0.318 0.309 0.321 0.309

28 Floor Plt10 0.310 0.307 0.302 0.318 0.314 0.302

API-653 STORAGE TANK EVALUATION

AST Component Inspection Data

File No Report No Client Inspector Tank No. Date

Critical Zone Thickness Measurements (in inches) The following CMLs were taken within 2” of the chime weld at 2’ intervals, 360°

CML Loc Thickness

1 0 ft 0.318

2 2 ft 0.309

3 4 ft 0.310

4 6 ft 0.328

5 8 ft 0.323

6 10 ft 0.331

7 12 ft 0.319

8 14 ft 0.334

9 16 ft 0.318

10 18 ft 0.318

11 20 ft 0.310

12 22 ft 0.313

13 24 ft 0.312

14 26 ft 0.314

15 28 ft 0.315

16 30 ft 0.309

17 32 ft 0.309

18 34 ft 0.320

19 36 ft 0.318

20 38 ft 0.310

21 40 ft 0.311

22 42 ft 0.310

23 44 ft 0.307

24 46 ft 0.309

25 48 ft 0.308

26 50 ft 0.304

CML Loc Thickness

27 52 ft 0.319

28 54 ft 0.334

29 56 ft 0.318

30 58 ft 0.310

31 60 ft 0.314

32 62 ft 0.319

33 64 ft 0.318

34 66 ft 0.309

35 68 ft 0.310

36 70 ft 0.323

37 72 ft 0.325

38 74 ft 0.323

39 76 ft 0.331

40 78 ft 0.324

41 80 ft 0.321

42 82 ft 0.322

43 84 ft 0.323

44 86 ft 0.320

45 88 ft 0.318

46 90 ft 0.311

47 92 ft 0.307

48 94 ft 0.320

49 96 ft 0.315

50 98 ft 0.313

51 100 ft 0.312

52 102 ft 0.312

API-653 STORAGE TANK NOZZLE EVALUATION

Nozzle Inspection Data

Nozzle Thickness Measurements (in inches)

Components with Vert. Axis: tml-1 N., tml-2 E., tml-3 S., tml-4 W. (Drawing N.)

Components with Horiz. Axis: tml-1 Top, tml-2 Side, tml-3 Btm., tml-4 Side (Clockwise)

CML Description Size Location tml-1 tml-2 tml-3 tml-4 Minimum x y

N1 Reference manway 36" 0 47" 0.504 0.502 0.496 0.505 0.496

N2 Receipt 10" 13' 27" 0.576 0.571 0.582 0.566 0.566

N3 Issue 14" 38'6" 28" 0.581 0.560 0.561 0.566 0.560

N4 Pump out 4" 41'8" 20" 0.337 0.341 0.348 0.342 0.337

N5 Manway 36" 51'5" 47" 0.507 0.508 0.510 0.502 0.502

N6 Manway 36" Roof 0.194 0.196 0.203 0.187 0.187

N7 Gauge well 14" Roof 0.509 0.500 0.503 0.508 0.500

N8 Vent 12" Roof 0.408 0.410 0.409 0.412 0.408

Reinforcement Plate Details

Noz ID Size Shape Thickness Weephole Acceptable

N1 68"x74" Tombstone 0.316 Yes Yes

N2 26"x24" Tombstone 0.25 Yes Yes

N3 36"x32" Tombstone 0.245 Yes Yes

N4 16"x12" Tombstone 0.244 Yes Yes

N5 68"x74" Tombstone 0.304 Yes Yes

N6 28" Round 0.362 NA Yes

APPENDIX C

API 653 Inspection Checklist

1) API-653 In-Service Checklist

2) API-653 Out-of-Service Checklist

YES NO N/A

Measure foundation levelness and bottom elevations. X

C.1.1.1 Concrete Ring

a) Inspect for broken concrete, spalling and cracks, particularly under backup bars used in welding butt-welded annular rings under the shell.

b) Inspect drain openings in ring, back of waterdraw basins and top surface of ring for indications of bottom leakage.

c) Inspect for cavities under foundation and vegetation against bottom of tank.

d) Check that runoff rainwater from the shell drains away from tank. X

e) Check for settlement around perimeter of tank. X

C.1.1.2 Asphalt

a) Check for settling of tank into asphalt base which would direct runoff rain water under the tank instead of away from it.

b) Look for areas where leaching of oil has left rock filler exposed, which indicates hydrocarbon leakage.

C.1.1.3 Oiled Dirt or Sand

Check for settlement into the base which would direct runoff rain water under the tank rather than away from it.

C.1.1.4 Rock

Presence of crushed rock under the steel bottom usually results in severe underside corrosion. Make a note to do additional bottom plate examination when the tank is out of service.

C.1.1.5 Site Drainage

a) Check site drainage away from the tank and associated piping. X

b) Check operating condition of the dike drains. X

C.1.1.6 Housekeeping

Inspect the area for buildup of trash, vegetation and other debris. X

C.1.1.7 Cathodic Protection

Review cathodic protection potential readings. X

C.1.2 SHELLS

C.1.2.1 External Visual Inspection

a) Visually inspect for paint failures, pitting and corrosion. X

b) Clean off the bottom angle area and inspect for corrosion and thinning on plate and weld.

c) Inspect the bottom-to-foundation seal, if any. X

C.1.2.2 Internal (Floating Roof Tank)

Visually inspect for grooving, corrosion, pitting and coating failures. X

C.1.2.3 Riveted Shell Inspection

a) Inspect external surface for rivet and seam leaks. X

b) Locate leaks by sketch or photo. X

API-653 AST INSPECTION CHECKLIST

C.1.1 FOUNDATION

X

Facility Name:

X

X

X

Inspector:

Barksdale Air Force Base

Richard A. Laton Jr. (API-653 #2163)

Tank Number:

Date:

6350-2

11/14/2011

Tank In-Service Inspection Checklist

ITEM

X

X

X

X

C.1.2.3 Riveted Shell Inspection (cont.)

c) Inspect rivets for corrosion loss and wear. X

d) Inspect vertical seams for full fillet lap-welds for better efficiency. X

e) Sketch or photograph rivet patterns if no records exist. X

C.1.2.4 Wind Girder (Floating Roof Tanks)

a) Inspect wind girder and handrail for corrosion damage and for broken welds.

b) Check support welds to shell for pitting, especially on shell plates. X

c) Note whether supports have reinforcing pads welded to shell. X

C.1.3 SHELL APPURTENANCES

C.1.3.1 Manways and Nozzles

a) Inspect for leakage at nozzles, manways and repads. X

b) Check support welds to shell for pitting, especially on shell plates. X

c) Inspect for flange leaks and leaks around bolting. X

d) Inspect sealing of insulation around manways and nozzles. X

e) Check for inadequate manway flange and cover thickness. X

C.1.3.2 Tank Piping Manifolds

a) Inspect manifold piping, flanges and valves for leaks. X

b) Inspect fire fighting system components. X

c) Check for anchored piping which would be hazardous to the tank shell or bottom connections during earth movement.

d) Check for adequate thermal pressure relief of piping to tank. X

e) Check operation of regulators for tanks with purge gas systems. X

f) Check sample connections for leaks and for proper valve operation. X

g) Check for damage and test the accuracy of temperature indicators. X

h) Check welds on shell-mounted davit clips on valves 6" and larger. X

C.1.3.3 Autogauge System

a) Inspect autogauge tape guide and lower sheave housing for leaks. X

b) Inspect autogauge head for damage. X

c) Bump the checker on autogauge head for proper tape movement. X

d) Identify size and construction material of gauge tape guide. X

e) Ask operator if tape tends to hang up during tank roof movement. X

f) Compare actual product level to the reading on the gauge. X

g) On floating roof tanks, when the roof is in the lowest position, check there is no more than 2' of exposed tape at end of tape guide.

h) Inspect condition of board and legibility of board type autogauges. X

i) Test freedom of movement of marker and float. X

C.1.3.4 Shell-mounted Sample Station

a) Inspect sample lines for function of valves and plugging of lines. X

b) Check circulation pump for leaks and operating problems. X

c) Test bracing and supports for sample lines and equipment. X

C.1.3.5 Heater (Shell Manway Mounted)

Inspect condensate drain for presence of oil indicating leakage. X

C.1.3.6 Mixer

a) Inspect for proper mounting flange and support. X

b) Inspect for leakage. X

c) Inspect condition of power lines and connections to mixer. X

ITEM

X

X

X

C.1.3.7 Swing Lines: Winch Operation

a) Nonfloating: Raise, then lower the swing line with the winch and check for cable tightness to confirm that swing line lowered properly.

b) Floating: With tank half full or more, lower the swing line, then let out cable and check if swing has pulled cable tight indicating that the winch is operating properly.

c) Indicator. Check that the indicator moves in the proper direction:

Floating swing line indicators show a lower level as cable is wound up on the winch. Non-floating swing line indicators are the opposite.

C.1.3.8 Swing Lines: External Guide System

Check for leaks at threaded and flanged joints. X

C.1.3.9 Swing Lines: Identify Ballast Varying Need

Check for significant difference in stock specific gravity. X

C.1.3.10 Swing Lines: Cable Material and Condition

a) For nonstainless steel cable, check for corrosion. X

b) All cable: check for wear or fraying. X

C.1.3.11 Swing Lines: Product Sample Comparison

Check for water or gravity differences that would indicate a leak. X

C.1.3.12 Swing Lines: Target

Target should indicate direction of swing opening and height above bottom where suction will be lost with swing on bottom support.

C.1.4 ROOFS

C.1.4.1 Deck Plate Internal Corrosion

For safety, before accessing the roof, check with UT instrument or hammer test the deck plate near the edge of the roof for thinning.

C.1.4.2 Deck Plate External Corrosion

Visually inspect for paint failure, holes and corrosion on roof deck. X

C.1.4.3 Roof Deck Drainage

Look for indication of standing water. (Significant sagging of fixed roof deck indicates rafter failure.

C.1.4.4 Level of Floating Roof

At several locations, measure distance from roof rim to a horizontal weld seam above the roof. A variance in readings indicates a nonlevel roof with possible shell out-of-round, leaking pontoons or hang up. On small diameter tanks, an unlevel condition can indicate unequal loading at that level.

C.1.4.5 Gas Test Internal Floating Roof

Test for explosive gas on top of the internal floating roof. X

C.1.4.6 Roof Insulation

a) Visually inspect for cracks or leaks in the insulation weather coat where runoff rain water could penetrate the insulation.

b) Inspect for wet insulation under the weather coat. X

c) Remove small test sections of insulation and check roof deck for corrosion and holes near the edge of the insulated area.

C.1.4.7 Floating Roof Seal Systems

a) Inspect the condition of the seal, measure and record maximum rim spaces and seal-to-shell gaps around roof circumference.

ITEM

X

X

X

X

X

X

X

X

X

X

C.1.4.7 Floating Roof Seal Systems (cont.)

b) Measure and record annular space at 30' spacing (minimum of 4 quadrants) around roof and record. Measurements should be taken in directly opposite pairs.

1) 0"

2)

c) Check if seal fabric on primary shoe seals is pulling shoes away from shell (fabric not wide enough).

d) Inspect fabric for deterioration, holes, tears and cracks. X

e) Inspect visible metallic parts for corrosion and wear. X

f) Inspect for openings in seals that would permit vapor emissions. X

g) Inspect for protruding bolt or rivet heads against the shell. X

h) Pull both primary and secondary seal systems back all around the shell to check their operation.

i) Inspect secondary seals for signs of buckling or indications that their angle with the shell is too shallow.

j) Inspect wedge-type wiper seals for flexibility, resilience or tears. X

C.1.5 ROOF APPURTENANCES

C.1.5.1 Sample Hatch

a) Inspect condition and functioning of sample hatch cover. X

b) Check condition of seal inside hatch cover. X

c) Check for corrosion and plugging on thief and gauge hatch cover. X

d) Where sample hatch is used to reel gauge stock level, check for marker and tab stating hold-off distance.

e) Check for reinforcing pad where sample hatch pipe penetrates the roof deck.

f) On floating roof sample hatch and recoil systems, inspect the operation of recoil reel and condition of rope.

g) Test operation of system. X

h) On ultra clean stocks such as JP4, check for presence of protective coating or liner inside sample hatch.

C.1.5.2 Gauge Well

a) Inspect visible portion of the gauge well for thinning, size of slots and cover condition.

b) Check for hold-off distance marker and tab with hold-off distance. X

c) On floating roofs, inspect condition of roof guide for gauge well, particularly the condition of the rollers for grooving.

d) If accessible, check the distance from the gauge will pipe to the tank shell at different levels.

e) If tank has a gauge well washer, check valve for leakage and for presence of a bull plug or blind flange.

C.1.5.3 Fixed Roof Scaffold Support

Inspect scaffold support for corrosion, wear and structural defects. X

C.1.5.4 Autogauge: Inspection Hatch and Guides (Fixed Roof)

a) Check the hatch for corrosion and missing bolts. X

b) Look for corrosion on the tape guide's and float guide wires' anchors.

C.1.5.5 Autogauge: Float Well Cover

a) Inspect for corrosion. X

b) Check tape cable for wear or fraying caused by rubbing on cover. X

ITEM

X

X

X

X

X

X

X

X

X

X

X

X

X

C.1.5.6 Sample Hatch (Internal Floating Roof)

a) Check overall condition. X

b) When equipped with a fabric seal, check for automatic sealing after sampling.

c) When equipped with a recoil reel opening device, check for proper operation.

C.1.5.7 Roof-mounted Vents (Internal Floating Roof)

Check condition of screens, locking and pivot pins. X

C.1.5.8 Gauging Platform Drip Ring

On fixed roof tanks with drip rings under the gauging platform or sampling area, inspect for plugged drain return to the tank.

C.1.5.9 Emergency Roof Drains

Inspect vapor plugs for emergency drain; that seal fabric discs are slightly smaller than the pipe ID and that fabric seal is above the liquid level.

C.1.5.10 Removable Roof Leg Racks

Check for leg racks on roof. X

C.1.5.11 Vacuum Breakers

Report size, number and the type of vacuum breakers. Inspect vacuum breakers. If high legs are set, check for setting of mechanical breaker in high leg position.

C.1.5.12 Rim Vents

a) Check condition of the screen on the rim vent cover. X

b) Check for plating off or removal of rim vents where jurisdictional rules do not permit removal.

C.1.5.13 Pontoon Inspection Hatches

a) Open pontoon inspection hatch covers and visually check inside for pontoon leakage.

b) Test for explosive gas (an indicator of vapor space leaks). X

c) If pontoon hatches are equipped with locked down covers, check for vent tubes. Check that vent tubes are not plugged up. Inspect lock-down devices for condition and operation.

C.1.6 ACCESSWAYS

See Tank Out-of-Service Inspection Checklist, Item C.2.12. X

ITEM

X

X

X

X

X

X

X

X

C.2.1 OVERVIEW

a) Check that tank has been cleaned, is gas free and safe for entry. X

b) Check that tank is completely isolated from all energy sources. X

c) Check that roof is adequately supported, including fixed roof structure and floating roof legs.

d) Check for presence of falling object hazards from roof. X

e) Inspect for slipping hazards on the bottom and roof decks. X

f) Inspect structural welds on accessways and clips. X

g) Check surfaces needing inspection for a heavy scale build-up and check weld seams and oily surfaces where welding is to be done.

Note areas requiring more cleaning, including blasting.

h) Review cathodic protection potential readings. X

C.2.2 TANK EXTERIOR

a) Inspect appurtenances opened during cleaning such as lower floating swing sheave assemblies, nozzle interiors (after removal of valves).

b) Hammer test or UT the roof. X

c) Enter and inspect the floating roof pontoon compartments. X

C.2.3 BOTTOM INTERIOR SURFACE

a) Using a flashlight held close to and parallel to the bottom plates, and using the bottom plate layout as a guide, visually inspect and hammer test the entire bottom.

b) Measure the depth of pitting and describe the pitting appearance

(sharp edged, lake type, dense, scattered, etc).

c) Mark areas requiring patching or further inspection. X

d) Mark locations for turning coupons for inspection. X

e) Inspect all welds for corrosion and leaks, particularly the shell-to-bottom weld.

f) Inspect sketch plates for corrosion. X

g) Check condition of internal sump, if applicable. Standing liquid should be removed from the sump to allow for complete inspection and vacuum testing of weld seams as appropriate. Sump bottom and sidewall plate and seams need to be evaluated for both product-side and soil-side corrosion.

h) Locate and mark voids under the bottom. X

i) Record bottom data on a layout sketch using the existing bottom plates as a grid. List the number and sizes of patches required.

j) Vacuum test the bottom lap welds. X

k) Hammer test or ultrasonically examine any slightly discolored spots or damp areas.

l) Check for reinforcing pads under all bottom attached clips, brackets and supports.

m) Inspect floating roof leg pads for pitting or cutting, and excessive dimpling (indicating excessive loading).

n) Check the column bases of fixed roof supports for adequate pads and restraining clips.

X

Tank Out-Service Inspection Checklist

ITEM

X

X

X

X

X

X

X

X

X

X

X

C.2.3 BOTTOM INTERIOR SURFACE (cont.)

o) In earthquake Zones 3 and 4, check that roof supports are not welded down to the tank bottom, but are only restrained from horizontal movement.

p) Check area beneath swing line cable for indications of cable cutting or dragging.

q) Mark old oil and air test connection for removal and patching. X

r) Identify and report low areas on the bottom that do not drain adequately.

s) Inspect coating for holes, disbonding, deterioration and discoloration.

C.2.4 SHELL SEAMS AND PLATE

a) On cone up bottoms, closely inspect and gauge the depth of metal loss on the lower 2-4" of the shell (area of standing water).

b) Measure the depth of pitting on each course. X

c) Inspect and estimate the amount of metal loss on the heads of rivets and bolts.

d) Inspect shell-to-bottom riveted lap joints. X

e) Inspect for vertical grooving damage from seal assembly protrusions.

f) Inspect existing protective coatings for damage, deterioration and disbonding.

g) Check for areas of rubbing (indicating too much pressure by the seal assembly shoes or inadequate annular space).

h) Visually inspect the shell plates and seams for indications of leakage.

i) If the shell has riveted or bolted seams, record the leak locations by film or chart in case the locations are lost during preparation for painting.

j) Measure annular space at 40' intervals. X

k) Survey the shell to check for roundness and plumb. X

C.2.5 SHELL-MOUNTED OVERFLOWS

a) Inspect overflow for corrosion and adequate screening. X

b) Check location of overflow that it is not above any tank valves or equipment.

C.2.6 ROOF INTERIOR SURFACE

C.2.6.1 General

a) Visually inspect the underside surface of the roof plates for holes, scale buildup and pitting.

b) Hammer test or UT to check for thin areas, particularly in the vapor space of floating roofs and at edge of roof on cone roof tanks.

c) Check all clips, brackets, braces, etc., welded to the roof deck plate for welded reinforcing pads and see that they have not broken free.

d) If no pad is present, PT for cracking of the weld or deck plate. X

e) Inspect for protective coating for breaks, disbonding and deterioration.

f) Spark test the interior surface coating if recoating is not planned. X

ITEM

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

C.2.6.2 Fixed Roof Support Structure

a) Inspect the support columns for thinning in the upper 2'. X

b) On API columns (two channels welded together) check for corrosion scale breaking the tack welds, unless the joint between the channels is completely seal welded.

c) Check that the reinforcing pad on the bottom is seal-welded to the tank bottom with horizontal movement restraining clips welded to the pad.

d) Determine if pipe column supports are concrete filled or open pipe. If open pipe, check for a drain opening in the pipe bottom.

e) Inspect and gauge rafters for thinning, particularly near the center of the roof. Report metal loss.

f) Check for loose or twisted rafters. X

g) Inspect girders for thinning and check that they are attached securely to the top of the columns.

h) Report if the columns have cross bracing in the area between the low pump out of the top of the shell (for future internal floating roof installation.)

i) Inspect and report presence of any roof mounted swing line bumpers.

j) Photograph the roof structure if no rafter layout drawing exists. X

C.2.7 FIXED ROOF APPURTENANCES

C.2.7.1 Inspection and Light Hatches

a) Inspect the hatches for corrosion, paint and coating failures, holes and cover sealing.

b) On loose covers, check for a safety chain in good condition. X

c) On light hatches over 30" across, check for safety rods. X

d) Inspect the condition of the gaskets on latched down hatch covers. X

C.2.7.2 Staging Support Connection

Inspect the condition of the staging support for corrosion. X

C.2.7.3 Breathers and Vents

a) Inspect and service the breather. X

b) Inspect screens on vents and breathers. X

C.2.7.4 Emergency P/V Hatches

a) Inspect and service P/V hatches. (Setting should be high enough to prevent chattering of breather during normal operation. See breather manufacturer's guide).

b) Inspect liquid seal hatches for corrosion and proper liquid level in the seal.

C.2.7.5 Sample Hatch

a) Inspect sample hatch for corrosion. X

b) Check that the cover operates properly. X

c) If the tank has no gauge well, check for a hold-off distance marker and check measurement.

C.2.8 FLOATING ROOF

C.2.8.1 Roof Deck

a) Hammer test the area between the roof rim and shell. (If access is inadequate, measure from bottom edge to corroded area).

b) In sour water service, clean and test all deck plate weld seams for cracking unless the lower laps have been seal-welded.

ITEM

X

X

X

X

X

X

X

X

X

X

X

X

X

C.2.8.1…