Attachment K.2- Tank 09651 Inspection Report.pdf

TANK 2

INSPECTION REPORT

Fort Lewis Tacoma, Washington

A/E Contract No. W9128F-05-D-0014 Delivery Order No. 001

Project No. MID 909 Survey

7 March 2007

Submitted to:

U.S. Army Corps of Engineers Omaha District

106 South 15th Street Omaha, NE 68102-1618

Submitted by:

Austin Brockenbrough & Associates, L.L.P.

Consulting Engineers

P.O. Box 4800, 4800 West Hundred Road Chester, Virginia 23831

Phone: 804-748-8746 Fax: 804-748-7849 www.brockenbrough.com

AB&A Job No. 05-081F

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TANK 2

INSPECTION REPORT

Fort Lewis

Tacoma, Washington A/E Contract No. W9128F-05-D-0014

Delivery Order No. 001 Project No. MID 909 Survey

Submitted to:

U.S. Army Corps of Engineers Omaha District

106 South 15th Street Omaha, NE 68102-1618

Submitted by:

Consulting Engineers

P.O. Box 4800, 4800 West Hundred Road Chester, Virginia 23831

Phone: 804-748-8746 Fax: 804-748-7849 www.brockenbrough.com AB&A Job No. 05-081F

Mr. Jimmy Brasch

General Construction Data Item Description

Owner U.S. Army Tank Identification Tank 2 Location Fort Lewis, Tacoma, Washington Manufacturer Morse Construction Group, Inc. – Everett, WA Design Standard API Std 650 Year Built 1997 Current Product Stored JP-8 Jet Fuel; Specific Gravity: 0.775 to 0.840; True Vapor

Pressure: 0.04 psia at 100°F; Flash Point: 100°F; Viscosity (kinematic): 1.9 x 10–5 ft2/s at 60°F; Class II combustible liquid.

Dimensions 31’-0” diameter x 21’-11” shell height Storage Capacity Nominal shell: 3,000 bbl; Useable: 2,000 bbl.

Previous Repairs None Foundation Sand filled ringwall.

RPB/Leak Detection Foundation drains to dike area.

Bottom Construction (20) 5/16" plates, lap-welded, cone-down to center sump.

Shell Construction Lower two courses: (4) 3/16" thk. x 7'-11 1/2"wide plates;

Top course: (4) 3/16” thk x 6’-0” wide plates;

Roof-to-shell rim angle: butt welded to shell, leg-out.

Fixed Roof Construction (14) 5/16" plates, lap welded, cone-up (4:12 slope), self-supported.

Stairs/Ladders Circumferential stairway.

Manholes (2) 24" lower shell manway; (1) 36" roof manhole.

Cathodic Protection Impressed current system Interior Coating System System unknown; 100% of interior surfaces.

Exterior Coating System System unknown; 100% of exterior surfaces.

Level Gauging MTS Magnetostrictive Automatic Tank Gauge (ATG).

Overfill Protection/Level Alarms

Hydraulic LCV. Shell mounted LCV float switch at 20'-7". ATG actuated alarms: HH: 20'-10", H: 19'-9 1/2", L: 4'-3 3/8”, LL: 2'-1 1/2”. Alarms audible and visible. Shell mounted level switches:

HH: 19'-6 1/2": L:1'-4": Roof mounted high level switch at 19'- 11 1/2".

Interior Piping 4” Fill; 4” Suction; 3” Low-Suction; 1” Water Draw-off.

Strapping Tables Original strapping tables are available.

Water Draw-Off System Yes Secondary Containment Below grade concrete dike area.

Fire Protection System Fire hydrants at 229’ and 241’; Semi-fixed AFFF System.

The UT measurements of the tank shell did not indicate any problems. The minimum recorded thickness measurements for each shell course (listed from the bottom to the top course) are as follows: 0.180, 0.180, and 0.178 inches. The shell settlement, peaking, banding, and plumbness were also measured and determined to be acceptable.

UT measurements of the tank’s lap welded cone roof ranged from 0.301 to 0.317 inches. The tank roof has the following appurtenances: 36 inch manhole, a center 6 inch pressure/vacuum vent mounted on a 4 inch nozzle, a 24 inch emergency vent, and three small penetrations for the mechanical type tank gauge, the electronic level indicator is installed through an 8 inch nozzle penetrating the roof manway cover. Fall protection is provided by a roof perimeter handrail which appears to be well built and in good condition. The roof appears to be properly self-supported, continuously sloped and without any evidence of water ponding.

The inspection also included an examination of the tank’s coating systems. The exterior coating system appeared to be the standard military white epoxy/polyurethane system. The dry film thickness measurement results were: 11.1 to 17.2 mils on the exterior of the shell. The interior coating system is an unknown type measuring 38.5 to 64.5 mils on the tank shell and 43.7 to 59.2 mils on the tank bottom. Most of the coating systems generally appeared to be in fair condition although the joint sealant used to form an interior cove at the shell to bottom joint is cracked as my be seen in Photograph 1, and the internal factory coating system on the emergency vent has failed. The exterior roof coating at the roof mounted scully high level alarm has failed. There is also a lot of mold and microbial growth covering the exterior of the roof see Photograph 2.

ETI’s API Standard 653 Out-of-Service Inspection Report, which is attached, includes all of the results from the non-destructive testing. The report also includes sketches of the floor, shell and roof plates with any anomalies indicated. ETI’s recommendations are generally included in our recommendations which follow, however, we may have in some cases modified, omitted or contradicted their recommendations. Any major discrepancy with ETI’s report is noted in this report summary.

Cathodic Protection

The cathodic protection survey established that the impressed current type cathodic protection system, which includes anodes installed in the sand between the tank bottom and the non-conductive liner, is providing adequate protection to the tank bottom.

The inspection also identified two insulating flanges on the product piping. Insulating flanges are unnecessary where tanks are insulated from the native soil by non-conductive undertank liners. The maintenance of insulating flanges is often a problem for maintenance personnel, therefore the insulating washers and sleeves should be removed from the flange bolts. The bolting should be reinstalled without the insulators and with stainless steel washers. The insulating gaskets are only slightly less conductive than a regular gasket and would not need to be replaced for this purpose.

Required Repairs/Upgrades

Required repairs/upgrades are those that are immediately necessary to address either structural integrity problems or the potential for leakage and must be performed prior to returning the tank to service. These repairs/upgrades may also address the most serious of the non-compliance issues related to codes, industry standards, or military standards. The tank was generally constructed using standard practices and found to be in good condition.

Code Compliance Upgrades

Code compliance upgrades are the improvements that would need to be performed in order to fully comply retroactively with current applicable codes. Any items required before the tank is returned to service would be noted above and are not duplicated here. The higher priority items are typically safety or environmentally related, thus they should be considered for implementation in the near future or during the next scheduled outage.

The recommendations are based upon the following codes:

40 CFR 112 – Oil Pollution Prevention and Response [SPCC Plans] (July 17, 2002) 29 CFR 1910.106 – Flammable and Combustible Liquids (September 13, 2005)

The inspection identified only a couple of code compliance issues. The most significant code compliance issue is the aluminum high level control valve, shown in Photograph 1, which is not allowed by 29 CFR 1910.106, NFPA 30, and UFC 3-460-01. The complete list of code compliance upgrades is included on page 9.

Industry Standard Compliance Upgrades

Industry standard compliance upgrades are improvements that, while not necessarily required, would bring the tank up to generally accepted industry practices. Any items required before the tank is returned to service or related to a code requirement would be noted above and are not duplicated here. The higher priority items are typically safety or environmentally related, thus they should be considered for implementation in the near future or during the next scheduled outage.

The recommendations are based upon the following standards:

API Standard 650 – Welded Steel Tanks for Oil Storage (Tenth Edition, Addendum 4, December 2005) API Standard 653 – Tank Inspection, Repair, Alteration, and Reconstruction (Third Edition, Addendum 2, November 2005) NFPA 30 – Flammable and Combustible Liquids Code (2003)

The only industry standard non-compliance issues that were identified were the lack of an intermediate curb between the tanks and the insulating flanges on the product piping which was discussed above under the Cathodic Protection Section. These issues are included in the list of industry standard compliance upgrades on page 10.

Military Standard Compliance Upgrades

Military standards compliance repairs/upgrades are the improvements that would need to be performed in order to fully comply retroactively with current applicable military standards. Any items required before the tank is returned to service or related to a code requirement or industry standard would be noted above, and are not duplicated here. With regard to UFC 3-460-01, a higher priority has been placed on applicable issues identified in Section 12: “Major Rehabilitation” versus issues identified elsewhere in the document.

The recommendations are based upon the following current military standards:

UFC 3-460-01 – Design: Petroleum Fuel Facilities (January 2004) Standard Design AW 78-24-27 – Aboveground Vertical Steel Tanks (February 1993)

The inspection identified several military standards compliance issues, but none of them are very serious. We do recommend the higher priority items be considered for long term operation and maintenance of the tank, but the lowest priority items should not be considered important or necessary. The complete list of the Military Standards Compliance Upgrades is included starting on page 11.

Photograph 1 – Interior Shell to Bottom Joint The 50 mil thick coating is cracked over the caulk used to provide a smooth shell-to-bottom transition.

Photograph 2 – Pressure Vacuum Vent and Roof Tank has a pressure vacuum vent and AFFF instead of a floating pan as allowed by NFPA 30. However, current military standards require a floating pan for jet fuel, without exception.

Photograph 4 – Stairway, Alarms, and Controls The high level control valve float chamber (right) and the high level switch chamber (just left of center) are not accessible from the stairway as required by military standards.

Photograph 3 – Tank Piping There is limited access to appurtenances, valves, etc. between the suction and issue piping.

Photograph 6 – Foundation to Bottom Seal The foundation to bottom seal is failing.

Photograph 5 – Dike Wall Water from surrounding soil appears to have been seeping into the dike area through the cracks in the below grade dike walls.

Code Compliance Upgrades and Cost Estimates Repair/Upgrade Description

(in order of priority) Estimated

Construction Cost

a. 29 CFR 1910.106 § (c) (2), NFPA 30 § 5.3.3 and UFC 3-460-01 §

3.6.9.1: Replace the aluminum high level control valve with a steel valve.

$10,000

b. 40 CFR Part 112 §112.7 (g) (5) and UFC 3-460-01: Provide facility lighting to permit night operations, ensure safety and improve security. See cover photograph.

$50,000

Contractor Overhead and Profit (20%) $12,000 Code Compliance Upgrades Total (rounded) $72,000.00

Industry Standards Compliance Upgrades and Cost Estimates

(in order of priority)

Estimated Construction Cost

a. NFPA 30 § 4.3.2.3.2.f and UFC 3-460-01 § 8.11.1: Provide intermediate containment curb.

$20,000

b. NFPA 30 § 4.5.3.4: Remove insulating sleeves and washers from the issue and receipt piping insulating flange bolting, provide stainless steel washers, and reinstall the bolting without the insulators.

$2,000

Contractor Overhead and Profit (20%) $4,400 Industry Standards Compliance Upgrades Total (rounded) $26,400.00

Military Standards Compliance Upgrades and Cost Estimates

(in order of priority)

Estimated Construction Cost

a. UFC 3-460-01 § 2.17.2: Remove roof mounted level alarm to eliminate a possible focal point for static electricity discharge.

$2,000

b. UFC 3-460-01 § 8.11.8: Provide access to valves and other appurtenances located between the low suction and fill piping. See Photograph 3.

$10,000

c. UFC 3-460-01, Table 2, Item n and § 12.3.8: Reprogram the ATG to provide back-up to the shell mounted level alarms at the required levels.

$10,000

d. UFC 3-460-01, Table 2 Item e and § 12.3.1: Replace existing (2) 24” shell manholes with (2) 36” shell manholes.

$30,000

e. UFC 3-460-01 § 12.9: Provide a double block and bleed valve upstream of the level control valve.

$20,000

f. UFC 3-460-01 § 2.16: Provide identification tags on low suction valves.

$5,000

g. UFC 3-460-01 Table 2, Item u: Relocate the high level control float chamber to make it accessible and testable from the stairway. The stairway and level chambers may be seen on the cover photograph.

and in Photograph 4.

$15,000

h. UFC 3-460-01 Table 2, Item i, and Standard Design AW 78-24-27:

Provide the stairway with an intermediate platform to access the high level switch and level control float chambers. The stairway and level chambers may be seen on the cover photograph.

$50,000

i. UFC 3-460-01, Table 2, Item j: Provide shell mounted high and high-high level alarms that are accessible and testable from the new spiral stairway.

$20,000

j. UFC 3-460-01, Table 2 Item p and § 8.6.3 (e): If a floating pan is provided, provide also a 10” roof nozzle and 8” stilling well with pole sleeve for the ATG, and if floating pan is not provided, continuously slot the existing stilling well to within 2’-0” of the roof.

$15,000

k. UFC 3-460-01, Table 2, Item r: Provide 10-inch roof nozzle and 8” slotted aluminum stilling well with gauge hatch, datum plate.

$15,000

l. UFC 3-460-01, Table 2 Item q and § 8.6.3: Provide 10” roof nozzle and 8” water bottom sampling gauge well, and if floating pan is also provided include with pole sleeve.

$15,000

m. UFC 3-460-01, Table 2 Item d: Provide roof inspection hatches. $15,000

n. UFC 3-460-01, Table 2 Item cc: Provide two scaffold cable supports in accordance with API 650.

$10,000

Military Standards Compliance Upgrades and Cost Estimates

(in order of priority) Estimated

Construction Cost

o. UFC 3-460-01 § 8.3.12 and Standard Design AW 78-24-27: Provide an electric motor driven pump on the product saver tank and provide a product recovery tank.

$50,000

p. UFC 3-460-01 § 8.3.9: Replace the 4” receipt piping and 4” tank receipt nozzle and diffuser to insure the velocity of the fuel does not exceed 12 feet per second at maximum flow rate (all receipt pumps running).

$50,000

q. UFC 3-460-01 § 2.13.5.5 and 8.11.7: Provide oil/water separator to process stormwater that collects in dike area.

$100,000

r. UFC 3-460-01 § 8.6.3: Provide internal floating pan and related appurtenances.

$150,000

Clean and gas free the tank before making the above tank modifications.

$20,000

Repair the coating where damaged by the above repairs. $40,000 Contractor Overhead and Profit (20%) $128,000 Military Standards Compliance Upgrades Total (rounded) $770,000.00

General Maintenance Repairs General maintenance repairs are issues that, while not of immediate concern or of a serious nature at this time, may become detrimental to the tank’s structural integrity and/or its tightness.

We suggest they be monitored regularly or performed in a timely manner. The complete list of these repairs/upgrades is included starting on page 13.

The inspection identified a few general maintenance issues. The most noteworthy of the issues are cracks in the below grade dike wall with signs of ground water seeping into the dike area, as shown in Photograph 5, mold growth on the exterior of the roof, as shown in Photograph 2, and exterior coating failure on the tank roof, see photograph in ETI Report. A complete list of general maintenance repair recommendations is included on page 14.

General Facility Overview

In addition to the tank inspection, the surrounding site and facility were reviewed for general compliance with industry standards and the current codes and standards listed previously.

Except as mentioned, the drainage systems, access roads, and utilities appeared to be well maintained and in good condition. However, the adjacent truck loading/unloading facility may not have adequate secondary containment. It is recommended that an evaluation of the truck loading/unloading facility be performed.

General Maintenance Repairs and Cost Estimates

(in order of priority) Estimated

Construction Cost

a. Replace the vent screen on the roof. Repair can be performed by base personnel.

$0

b. Repair the interior coating system on the emergency vent. $2,000

c. Replace the tank bottom to foundation seal. See Photograph 6. $5,000

d. Clean and spot repair the exterior roof coating and overcoat with mold resistant polyurethane.

$10,000

e. Spot repair the coating system on the tank bottom. $10,000

f. Repair the numerous cracks in the concrete dike. Seal the exterior

(soil side) surfaces of the concrete dike wall. Coat the interior of the concrete dike with a moisture barrier sealant. See Photograph 5.

$75,000

Contractor Overhead and Profit (20%) $20,000 General Maintenance Repairs Total (rounded) $122,000.00

EXECUTIVE SUMMARY

An API Standard 653 Out-of-Service Inspection of Tank #2 was completed on October 6, 2006. The purpose of this inspection was to collect data and establish a data base for present and future inspections and evaluations. The containment area walls and floor have minor visible surface cracks. The bottom-to-foundation sealant has failed in several locations. The external coating system on the fixed roof electronic level indicator nozzle has failed. A shell settlement survey was performed, and the results were satisfactory. Nozzle and reinforcement evaluation of accessible shell nozzles shows that the nozzles are adequately reinforced and have a minimum remaining life of 47 years. A shell service life evaluation performed on all shell courses shows that the shell has a remaining life of 65 years under current conditions, thereby, the next external visual inspection should be accomplished by a Certified Inspector prior to October 2011, and the next external ultrasonic thickness measurement inspection should be accomplished by a Certified Inspector prior to October 2021 in accordance with API Standard 653. A bottom service life evaluation shows that the in-service interval of operation (years to next internal inspection) to be twenty years under current conditions, thereby, the next internal inspection should be accomplished by a Certified Inspector prior to October 2026 in accordance with API Standard

653. Inspection Results are listed in 4.0. Recommendations for Compliance with API Standard 653 are made in 5.0, and Other Recommendations are made in 6.0.

ER-USARMY-FTLEWIS-2

ii

TABLE OF CONTENTS

Section Page

Signature Page ............................................................................................................. i Executive Summary ................................................................................................... ii Table of Contents .................................................................................................... iii List of Appendices .................................................................................................... iv List of Acronyms and Abbreviations ....................................................................... v

1.0 Introduction

1.1 Purpose

2.0 References

2.1 American Petroleum Institute

2.2 American Society of Mechanical Engineers

2.3 Code of Federal Regulations

2.4 National Association of Corrosion Engineers

2.5 National Fire Protection Association

3.0 Tank Description

4.0 Inspection Results

4.1 Containment

4.2 Foundation

4.3 Bottom

4.4 Shell

4.5 Shell Appurtenances

4.6 Accessways

4.7 Fixed Roof

5.0 Recommendations for Compliance with API Standard 653

5.1 Containment

5.2 Foundation

5.3 Bottom

5.4 Shell

5.5 Shell Appurtenances

5.6 Accessways

5.7 Fixed Roof

iii

TABLE OF CONTENTS (Continued)

Section Page

6.0 Other Recommendations

6.1 Containment

6.2 Foundation

6.3 Bottom

6.4 Shell

6.5 Shell Appurtenances

6.6 Accessways

6.7 Fixed Roof

7.0 Serviceability

LIST OF APPENDICES

Appendix A Engineering Calculations Appendix B Engineering Drawings Appendix C Engineering Data Appendix D API Standard 653 Checklists for Tank Inspection Appendix E Photographs iv

LIST OF ACRONYMS AND ABBREVIATIONS

API American Petroleum Institute ASME American Society of Mechanical Engineers

CFR Code of Federal Regulations CP Cathodic Protection

ETI Environmental Technology, Incorporated

MFL Magnetic Flux Leakage MT Magnetic Particle Testing

NACE National Association of Corrosion Engineers NDT Non-Destructive Testing NFPA National Fire Protection Association

PSI Pounds Per Square Inch PT Penetrant Testing

RP Recommended Practice RT Radiography Testing

UT Ultrasonic Testing

VT Visual Testing v

1.0 INTRODUCTION

1.1 Purpose:

1.1.1 This report provides an engineering evaluation of Tank #2 located at the Ft. Lewis facility in Tacoma, Washington. This report summarizes the results of an API Standard 653 Out-of-Service Inspection conducted by Environmental Technology, Inc., Project Number 100157-5. This inspection was completed on October 6, 2006. Our policy is:

"Provide to the storage tank owner and/or manager the most precise and complete inspection and report possible."

2.0 REFERENCES

2.1 American Petroleum Institute:

2.1.1 API Recommended Practice 574, Inspection Practices for Piping System Components.

2.1.2 API Recommended Practice 575, Inspection of Atmospheric and Low-Pressure Storage Tanks.

2.1.3 API Standard 650, Welded Steel Tanks for Oil Storage.

2.1.4 API Recommended Practice 651, Cathodic Protection of Aboveground Petroleum Storage Tanks.

2.1.5 API Recommended Practice 652, Lining of Aboveground Petroleum Storage Tank Bottoms.

2.1.6 API Standard 653, Tank Inspection, Repair, Alteration, and Reconstruction.

2.2 American Society of Mechanical Engineers Codes:

2.2.1 ASME Boiler and Pressure Vessel Code; Section V, Non-Destructive Examination.

2.2.2 ASME Boiler and Pressure Vessel Code; Section IX, Welding and Brazing Qualifications.

2.2.3 ASME Boiler and Pressure Vessel Code; Section VIII, Division 1, Rules for Construction of Pressure Vessels.

2.3 Code of Federal Regulations:

2.3.1 29 CFR 1910, Permit-Required Confined Spaces for General Industry.

2.3.2 40 CFR 112, Oil Pollution Prevention.

2.4 National Association of Corrosion Engineers:

2.4.1 NACE Recommended Practice, RP0184-91, Repair of Lining Systems.

2.4.2 NACE Recommended Practice, RP0193-93, External Cathodic Protection of On-Grade Metallic Storage Tank Bottoms.

2.4.3 NACE Recommended Practice, RP0288-94, Inspection of Linings on Steel and Concrete.

2.5 National Fire Protection Association:

2.5.1 NFPA-30, Flammable and Combustible Liquids Code.

3.0 TANK DESCRIPTION

3.1 Tank Description:

Owner/Operator: Ft. Lewis Location: Tacoma, Washington Tank Number: 2 Service: JP-8 Specific Gravity: 0.84 Diameter: 31.0 feet Shell Height: 21.83 feet Maximum Level: 20.5 feet (set by Owner/Operator) Capacity: 100,000 gallons Configuration: Vertical Foundation: Concrete Ringwall Construction: Bottom: Lap-Welded

Shell: Course #1: Butt-Welded Course #2: Butt-Welded Course #3: Butt-Welded

Fixed Roof: Lap-Welded Material: Bottom: A36

Shell: Course #1: A36 Course #2: A36 Course #3: A36

Fixed Roof: A36 Built: 1997 Age: 9 years Operating Limits: Minimum Metal Temperature: 30oF

Maximum Metal Temperature: Ambient Minimum Pressure: Atmospheric (no vacuum) Maximum Pressure: Product

Seismic Zone: 3 Construction Code: API Standard 650 Inspection Type: Out-of-Service Inspection Inspection Date: October 6, 2006 Last External Visual Inspection Year: 1997 Last External Ultrasonic Thickness Inspection Year: 1997 Last Out-of-Service Inspection Year: 1997

4.0 INSPECTION RESULTS

4.1 Containment: The containment area consists of vertical concrete walls with a concrete floor. The concrete walls and floor have minor surface cracks (see photographs in Appendix E).

The containment appears to be properly graded to drain water away from the tank bottom in accordance with NFPA 30-2.3.4.3(a). The containment area has a dike drain that is in satisfactory condition. The containment area volume appears to be sufficient to contain the stored product. The permeability of the secondary containment area is unknown due to the cracks on the visible surface. Overall, the containment is in satisfactory condition.

4.2 Foundation: The foundation consists of a concrete ringwall. The bottom-to-foundation sealant has failed in several locations (see photographs in Appendix E). The foundation was evaluated for shell settlement in accordance with API Standard 653 and is in satisfactory condition. Overall, the foundation is in satisfactory condition.

4.3 Bottom: The tank has a lap-welded cone down bottom with a butt-welded annular ring.

The bottom has a thick film liner ranging from 43.7 mils to 59.182.2 mils in thickness. The liner is in satisfactory condition with only minor cracks on the surface coating evident (see photographs in Appendix E). The tank bottom does not have leak detection or secondary containment. The nominal thickness of the bottom plates is 0.3125 inches, and the nominal thickness of the annular ring is 0.3125 inches. The bottom was scanned (approximately 95%) for underside corrosion using Magnetic Flux Leakage (MFL) technology and revealed no significant underside corrosion. The bottom was examined visually with the aid of a light held parallel to the bottom plates, which illuminates pitting and other discrepancies. No stockside pitting was found. Random thickness measurements of the bottom plates range from a minimum of 0.302 inches to a maximum of 0.316 inches, excluding the underside corrosion indications located by the MFL scan. Random thickness measurements are listed in the Bottom Plate Thickness Measurements table in Appendix C. A bottom service life evaluation shows that the in-service interval of operation (years to next internal inspection) to be twenty years under current conditions, thereby, the next internal inspection should be accomplished by a Certified Inspector prior to October 2026 in accordance with API Standard 653. The bottom service life evaluation is shown in Appendix A. A visual examination of the welds shows them to be in satisfactory condition. The bottom is in satisfactory condition.

4.4 Shell: The tank consists of three (3) butt-welded courses. The exterior of the shell has a thin coating system ranging between 11.1 and 17.2 mils in thickness. The interior of the shell has a thin coating system ranging between 38.5 and 64.5 mils in thickness. The exterior and interior coating of the shell are in satisfactory condition. The shell was evaluated for remaining metal thickness using ultrasonic technology. Thickness measurements are listed in the Shell

Plate Thickness Measurements table in Appendix C. A shell service life evaluation performed on all shell courses shows that the shell has a remaining life of 65 years under current conditions, thereby, the next external visual inspection should be accomplished by a Certified Inspector prior to October 2011, and the next external ultrasonic thickness measurement inspection should be accomplished by a Certified Inspector prior to October 2021 in accordance with API Standard

653. The shell service life evaluation is shown in the Shell Service Life Evaluation table in Appendix A. Roundness, plumbness, peaking, and banding of the shell are within the allowable tolerances of API Standard 653. The shell is in satisfactory condition.

4.5 Shell Appurtenances: The nozzles and reinforcement plates were evaluated in accordance with API Standards 650 and 653 and are in satisfactory condition. The accessible shell nozzles and reinforcements were evaluated for remaining metal thickness using ultrasonic technology.

Thickness measurements are listed in the Shell Nozzle and Nozzle Reinforcement Measurements table in Appendix C. A shell nozzle and reinforcement evaluation was performed on all accessible nozzles. Ultrasonic thickness measurements on the nozzles reveal no significant loss of metal from corrosion and erosion. All nozzles that were accessible to ultrasonic examination have a minimum remaining life of 47 years. All nozzles are adequately reinforced. The shell nozzle and reinforcement evaluation is shown in the Shell Nozzle and Reinforcement Evaluation table in Appendix A. The product level is monitored by a standard ATG and by an electronic level indicator. The ATG system is in satisfactory condition.

4.6 Accessways: The fixed roof is accessible via a spiral stairway The fixed roof accessway has steel grating treads with a 1.5 inch steel pipe handrails. The fixed roof accessway is welded directly to the shell as opposed to reinforcement pads as recommended by API Standard 653.

The accessway is in satisfactory condition.

4.7 Fixed Roof: The fixed roof is a self-supported cone roof. The coating system is in satisfactory condition. Fixed roof nozzle C, the electronic level indicator, has coating failure and corrosion (see photographs in Appendix E). The nominal thickness of the fixed roof is 0.3125 inches. The fixed roof was evaluated for remaining metal thickness using ultrasonic technology.

The fixed roof thickness ranges from a minimum of 0.301 inches to a maximum of 0.317 inches.

Thickness measurements are listed in the Fixed Roof Plate Thickness Measurements table in Appendix C. The fixed roof is in satisfactory condition.

5.0 RECOMMENDATIONS FOR COMPLIANCE

WITH API STANDARD 653

5.1 Containment: None.

5.2 Foundation: None.

5.3 Bottom: None.

5.4 Shell: None.

5.5 Shell Appurtenances: None.

5.6 Accessways: None.

5.7 Fixed Roof: None.

6.0 OTHER RECOMMENDATIONS

6.1 Containment: Fill the minor surface cracks within the containment area with a suitable material to ensure the area is non-permeable to the stored product.

6.2 Foundation: Remove the failed bottom-to-foundation sealant to prevent moisture intrusion beneath the tank bottom.

6.3 Bottom: Repair the coating failures on the tank bottom.

6.4 Shell: None.

6.5 Shell Appurtenances: None.

6.6 Accessways: None.

6.7 Fixed Roof: Remove the corrosion and coating failure on the electronic level indicator, roof nozzle C, and recoat.

7.0 SERVICEABILITY

7.1 Upon completion of the repairs to Tank #2 described in 5.0, the tank will be in compliance with the requirements of API Standard 653, and the following schedule may be implemented:

7.1.1 The next external visual inspection should be accomplished by a Certified Inspector prior to October 2011 in accordance with API Standard 653.

7.1.2 The next external ultrasonic thickness measurement inspection should be accomplished by a Certified Inspector prior to October 2021 in accordance with API Standard 653.

7.1.3 The next internal inspection should be accomplished by a Certified Inspector prior to October 2026 in accordance with API Standard 653.

Appendix A

Engineering Calculations

1.

2.

3.

4.

Bottom Service Life Evaluation Internal Shell Settlement Evaluation Shell Service Life Evaluation Shell Nozzle and Reinforcement Evaluation

A-1

MRTbc = RTbc - Orbc(StPr + UPr)

MRTip = RTip - Orip(StPr + UPr)

Orbc = RTbc - MRTbc

(StPr + UPr)

Orip = RTip - MRTip

(StPr + UPr)

Where:

MRTbc or MRTip = Minimum remaining thickness at the end of the in-service period of operation, in inches.

Or or Orbc or Orip = In-service interval of operation (years to next internal inspection), in years; however, Or shall not exceed 20 years.

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, in inches per year. StPr = 0 for coated areas of the bottom. The expected service life of the coating must equal or exceed Orip to use StPr = 0.

UPr = Maximum rate of corrosion on the bottom, in inches per year. To calculate the corrosion rate, use the minimum remaining thicknesses after repairs. Assume a linear rate based on the age of the tanks.

UPr = 0 for areas that have effective cathodic protection.

Note: For areas of a bottom that have been scanned by the magnetic flux leakage (or exclusion) process, and do not have effective cathodic protection, the thickness used for calculating UPr must be the lesser of the MFL threshold or the minimum thickness of corrosion areas that are not repaired. The MFL threshold is defined as the minimum remaining thickness to be detected in the areas inspected. The MFL unit used for scanning the bottom does not have a threshold set point. This unit visually displays all anomalies. The confidence level of this unit diminishes greatly for underside pitting/corrosion that is less than 0.04 inches in depth, based on company experience.

Areas of bottom side corrosion that are repaired should be evaluated with the corrosion rate for the repaired area unless the cause of corrosion has been removed. The evaluation is done by using the corrosion rate of the repaired area for UPr, and adding the patch plate (if used) thickness to the term "minimum of RTbc or RTip".

NOTE: The engineering data used to calculate the in-service interval of operation (Or) assumes the tank remains in the same service and all corrosion rates remain constant.

ER-USARMY-FTLEWIS-2

Bottom Service Life Evaluation

A-2

Present Condition: The tank bottom has a reinforced thick film liner (> 50 mils). The tank bottom does not have a cathodic protection system. The tank bottom does not have leak detection or secondary containment under the tank bottom.

MRTbc or MRTip RTip RTbc StPr UPr

0.1 inches

0.3125 inches

0.2725 inches * 0 inches/year

0.0044 inches/year

* The MFL unit used for scanning the bottom does not have a threshold set point. This unit visually displays all anomalies. The confidence level of this unit diminishes greatly for underside pitting/corrosion that is less than 0.04 inches in depth, based on company experience. No significant underside corrosion was detected. Therefore, RTbc is established at 0.2725 inches (original thickness of 0.3125 inches minus the 0.04 inches).

Orbc = RTbc - MRTbc = 0.2725 - 0.1 = 39 years(StPr + UPr) (0 + 0.0044)

Orip = RTip - MRTip = 0.3125 - 0.1 = 48 years(StPr + UPr) (0 + 0.0044)

Therefore, the in-service interval of operation (years to next internal inspection) is:

Or = 20 years

ER-USARMY-FTLEWIS-2

Bottom Service Life Evaluation

A-3

Maximum Permissible Out-of-Plane Deflection

| S | < 11L2Y

2EH

Where:

S L Y E H

Maximum permissible out-of-plane deflection, in feet.

Arc length between measurement points, in feet Yield strength, in pounds per square inch (psi) Young's modulus, in pounds per square inch (psi) Tank height, in feet

L Y E H S

12.17 feet 30,000 psi 29,000,000 psi

21.83 feet

0.0386 feet

ER-USARMY-FTLEWIS-2

Internal Shell Settlement Evaluation

A-4

Out-of-Plane Deflection

Si = Ui - (1/2Ui-1 + 1/2Ui+1) Where:

S U

Calculated out-of-plane deflection, in feet.

Out-of-Plane settlement of point "i", in feet (+) when above cosine curve (-) when below cosine curve

U1 U2 U3 U4 U5 U6 U7 U8

-0.0050 0.0156 0.0000 0.0056

-0.0150 0.0044

-0.0200 0.0044 feet feet feet feet feet feet feet feet

S1 S2 S3 S4 S5 S6 S7 S8

-0.0150 0.0181

-0.0106 0.0131

-0.0200 0.0219

-0.0244 0.0169 feet feet feet feet feet feet feet feet

The out-of-plane deflection is satisfactory since the magnitude of the highest calculated out-of-plane deflection, 0.0244 feet, is less than the magnitude of the maximum permissible out-of-plane deflection, 0.0386 feet.

ER-USARMY-FTLEWIS-2

Internal Shell Settlement Evaluation

A-5

Remarks/Legend:

Owner/Operator:

Inspection Firm:

Date: Revision Number: Revision Date:

Drawing Title: Tank Description: Drawing Number:

U.S. Army, Ft. Lewis, Tacoma, WA

Environmental Technology, Inc.

10/31/06 N/A N/A

Tank #2 SS-1Internal Shell Settlement Evaluation

Point #1 is at Seam #1 and each point is 45 degrees apart to the left viewing from the inside.

Seam #1 is the first seam right of the first manway right of the ladder in the first shell course viewing from the inside.

Out-of-Plane Settlement

Shell Settlement

Cosine Function Curve

Feet

Points 3 4 5 6 7 8 1 2 3

2.67

2.68

2.69

2.70

A -6

Client:

The maximum inspection intervals are determined by the most restrictive shell course in regard to the remaining life and the corrosion rate calculations for each shell course using the following formulas:

tmin=

2.6(H-1)DG

SE

Lr= tact - tmin Cr= tprev - tact Iut= tact - tmin Iv= tact - tmin

Cr Y 2Cr 4Cr

Where:

tmin = The minimum acceptable shell thickness for each course, in inches; however, tmin shall not be less than 0.1 inch for any tank course.

tnorm = The nominal shell thickness, in inches.

tact = The current measured shell thickness, excluding pits and corrosion, in inches.

tprev = The previous measured shell thickness, excluding pits and corrosion or tnorm, in inches.

D = The nominal diameter of the tank, in feet.

H = The height from the bottom of each shell course to the maximum liquid level, in feet.

Hc = The calculated safe fill height, in feet, for the current product.

G = The highest specific gravity of the contents.

Y = Specified minimum yield strength of the plate; use 30,000 pounds per square inch if not known (N/A for riveted tanks).

T = The smaller of the specified minimum tensile strength of the plate or 80,000 pounds per square inch; use 55,000 psi if not known (N/A for riveted tanks).

S = The maximum allowable stress, in pounds per square inch. For welded tanks, use the smaller of 0.80Y or 0.429T for the bottom and the second course or the smaller of 0.88Y or 0.472T for all other courses. For riveted tanks, use S=21,000 psi. For elevated temperatures above 200OF, the maximum allowable stress shall be the smaller of 2/3 the minimum yield strength multiplied by the M-factor (M) of API-650 Appendix M or the product design stress value listed in Table 3-2 of API-650.

E = The original joint efficiency for the tank. Use Table 2-1 from API Standard 653 if original E is unknown; 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 or twice the plate thickness. For riveted tanks, use E=1.0 for shell plates when greater than 6 inches from rivets; use the value of E from API-653 Table 2-1 when within 6 inches of rivets.

Lr = The remaining life of the shell, in years.

Cr = The shell corrosion rate, in inches per year.

Iut = The inspection interval for the next ultrasonic inspection, in years (not to exceed 15 years).

Iv = The inspection interval for the next visual external inspection, in years (not to exceed 5 years).

Y = The years between the previous measured shell thickness (tprev) and the current measured shell thickness (tact), in years.

ER-USARMY-FTLEWIS-2

Shell Service Life Evaluation

A-7

Present Condition:

Plate Material: A36

D H G Y

31.0 feet

21.83 feet 0.84 9 years

Course No.

Course Height (feet)

Maximum Allowable

Stress (psi) (S)

Joint Efficiency

(E)

Previous Measured Thickness (inches)

(tprev)

Current Measured Thickness (inches)

(tact)

Minimum Acceptable Thickness (inches)

(tmin)

Corrosion Rate

(in./yr) (Cr)

Remaining Life

(years) (Lr)

Next Visual

Inspection (years)

(Iv)

Next Ultrasonic Thickness Inspection

(years) (Iut)

1 7.92 24,882 1.00 0.1875 0.180 0.1 0.000833 96 5 15 2 7.92 24,882 1.00 0.1875 0.180 0.1 0.000833 96 5 15 3 6.0 27,376 1.00 0.1875 0.178 0.1 0.001056 73 5 15

The current measured thickness is based on the lowest ultrasonic thickness measurement for that course. The remaining life of the shell is 65 years under present conditions. The current maximum operating level of 20.5 feet is set by the Owner/Operator and is satisfactory. The next external visual inspection should be accomplished by a Certified Inspector prior to October 2011 in accordance with API Standard 653. The next external ultrasonic thickness measurement inspection should be accomplished by a Certified Inspector prior to October 2021 in accordance with API Standard 653.

ER-USARMY-FTLEWIS-2

Shell Service Life Evaluation

A-8 nt pD nR rnt

C hUse smaller value t2.5 or 2.5 tn t2.5 or 2.5t + ten Use smaller value t rt d et nd +or Rn+ t td +or R + t tnn Use larger value Use larger value

For nozzle wall abutting the vessel wallFor nozzle wall inserting through the vessel wall

Without Reinforcing Element

A

A

A

= A

= A

= A3

= dtrF+2tntrF(1-fr1) Area required

= d(E1t-Ftr)-2tn(E1t-Ftr)(1-fr1) Area available in shell; use larger value = 2(t+tn)(E1t-Ftr)-2tn(E1t-Ftr)(1-fr1)

= 5(tn-trn)fr2t Area available in nozzle projecting outward;

= 5(tn-trn)fr2tn use smaller value = 5 t ti fr2 Area available in inward nozzle;

= 5 ti ti fr2 use the smallest value = 2 h ti fr2

= outward nozzle weld = (leg)2fr2 Area available in outward weld = inward nozzle weld = (leg)2fr2 Area available in inward weld

If A1 + A2 + A3 + A41 + A42 > A Opening is adequately reinforced If A1 + A2 + A3 + A41 + A42 < A Opening is NOT adequately reinforced;

reinforcement required

With Reinforcing Element A A1

2A

A3

A

A

= A42

= A5

= Same as A, above Area required = Same as A1, above Area available in shell

= 5(tn-trn)fr2t Area available in nozzle projecting outward;

= 5(tn-trn)fr2t(2.5tn+te)fr2 use smaller value

= Same as A3, above Area available in inward nozzle

= outward nozzle weld = (leg)²fr3 Area available in outward welds = outer element weld = (leg)²fr4 Area available in outer welds = inward nozzle weld = (leg)²fr2 Area available in inward welds

= (Dp - d - 2tn)te fr4 Area available in element

If A1 + A2 + A3 + A41 + A42 + A43 + A5 > A Opening is adequately reinforced

ER-USARMY-FTLEWIS-2

Shell Nozzle and Reinforcement Evaluation

A-9

Minimum Required Thickness for Nozzles shall be determined from ASME Section VIII, Division 1, Part UG-27 as follows:

trn = PRn

SE - 0.6P

The remaining life of a tank or any of its components shall be determined using the formulas from API RP 575 as follows:

Cr = tprev - tact Lr = tact - trn

Y Cr

Where:

Dp = outside diameter of reinforcing element as measured vertically, inches.

D = outside diameter of pipe, inches.

d = finished diameter of circular opening in shell (inside diameter of nozzle), inches;

Where d = D - 2tn

E = joint efficiency of nozzle; Use E = 1.0 for API calculations.

F = correction factor for different plane variations; Use F = 1.0 for API calculations.

h = distance nozzle projects beyond the inner surface of the wall, inches. Not to exceed 4tn for API calculations.

P = internal design pressure, psi. Where, P = 0.433GH

Rn = inside radius of nozzle, inches; Where Rn = d/2 Sn = allowable stress in nozzle, psi.

fr = strength reduction factor; Use fr = 1.0 for API calculations.

leg = weld leg length, inches; Use leg = 0 for API calculations.

t = actual measured thickness of shell, inches; Use tact from Shell Service Life Evaluation.

tact = actual measured thickness of nozzle, inches.

tprev = previous measured thickness of nozzle or tn, inches.

te = thickness of reinforcement plate or thickness of thickened insert less the actual measured thickness of the shell (t), inches.

tr = minimum required shell thickness, inches; Use tmin from Shell Service Life Evaluation.

tn = external nominal pipe wall thickness, inches.

ti = internal nominal pipe wall thickness, inches; Use ti = tn if nozzle projects inward for

API calculations.

trn = required thickness of nozzle wall, inches.

G = product specific gravity; Use G from Shell Service Life Evaluation.

H = height of tank, feet; Use H from Shell Service Life Evaluation.

Cr = corrosion rate of nozzle, inches per year; Use Cr = 0.0002 inches/year, if Cr calculates to be less than 0.0002 inches/year.

LR = remaining life of nozzle, years.

Y = years between tprev and tact, in years.

ER-USARMY-FTLEWIS-2

A-10

Nozzle A: 4" Firefighting Foam Line (Course #3) d = 4.5 - 2(0.337) = 3.826 inches t = 0.178 inches Y = 9 years Rn = 3.826/2 = 1.913 inches tr = 0.1 inches Dp = N/A P = 0.433(0.84)(21.84) = 8 psi tn = 0.337 inches te = N/A h = 0 inches ti = 0 inches

Sn = 23,200 psi tprev = 0.337 inches E = 1 tact = N/A

Minimum Required Thickness Calculation:

trn = PRn = (8)(1.913) = 0.0007 inches

SE - 0.6P (23,200)(1) - (0.6)(8)

As a conservative approach, let trn=0.1 inches.

The Corrosion Rate Remaining Life Calculations cannot be calculated since thickness measurements cannot be taken on this nozzle. Visual inspection revealed no active corrosion. The remaining life of this nozzle is estimated to be greater than 50 years.

ER-USARMY-FTLEWIS-2

A-11

Nozzle B: 24" Manway (Course #1) d = 24 - 2(0.187) = 23.626 inches t = 0.18 inches Y = 9 years Rn = 23.626/2 = 11.813 inches tr = 0.1 inches Dp = 58 inches P = 0.433(0.84)(21.84) = 8 psi tn = 0.187 inches te = 0.1875 inches h = 0 inches ti = 0 inches

Sn = 23,200 psi tprev = 0.187 inches E = 1 tact = 0.173 inches

Minimum Required Thickness Calculation:

trn = PRn = (8)(11.813) = 0.0041 inches

SE - 0.6P (23,200)(1) - (0.6)(8)

As a conservative approach, let trn=0.1 inches.

Corrosion Rate Calculation:

Cr = tprev - tact = 0.187 - 0.173 = 0.001556 inches/year Y 9

Remaining Life Calculation:

LR = tact - trn = 0.173 - 0.1 = 47 years Cr 0.001556

Reinforcement Calculations:

Formulas are simplified A = dtr = (23.626)(0.1) = 2.3626 in2

A1 = d(t-tr) = (23.626)(0.18-0.1) = 1.8901 in2

= 2(t+tn)(t-tr) = (2)(0.18+0.187)(0.18-0.1) = 0.0587 in2

A2 = 5(tn-trn)t = (5)(0.187-0.1)(0.18) = 0.0783 in2

= 5(tn-trn)t(2.5tn+te) = (5)(0.187-0.1)(0.18)[(2.5)(0.187)+0.1875] = 0.0513 in2

A3

= 5t ti = (5)(0.18)(0) = 0 in2

= 5ti ti = (5)(0)(0) = 0 in2

= 2hti = (2)(0)(0) = 0 in2

A5 = (Dp-d-2tn)te = [58-23.626-(2)(0.187)](0.1875) = 6.375 in2

Area provided by A1 + A2 + A3 + A5=1.8901 in2 + 0.0513 in2 + 0 in2 + 6.375 in2=8.3164 inches2. This is greater than the required area of 2.3626 inches2, therefore, the reinforcement is adequate.

ER-USARMY-FTLEWIS-2

A-12

Nozzle C: 1" Low Level Indicator (Course #1) d = 1.315 - 2(0.179) = 0.957 inches t = 0.18 inches Y = 9 years Rn = 0.957/2 = 0.4785 inches tr = 0.1 inches Dp = N/A P = 0.433(0.84)(21.84) = 8 psi tn = 0.179 inches te = N/A h = 0 inches ti = 0 inches

Sn = 23,200 psi tprev = 0.179 inches E = 1 tact = N/A

Minimum Required Thickness Calculation:

trn = PRn = (8)(0.4785) = 0.0002 inches

SE - 0.6P (23,200)(1) - (0.6)(8)

As a conservative approach, let trn=0.1 inches.

The Corrosion Rate Remaining Life Calculations cannot be calculated since thickness measurements cannot be taken on this nozzle. Visual inspection revealed no active corrosion. The remaining life of this nozzle is estimated to be greater than 50 years.

ER-USARMY-FTLEWIS-2

A-13

Nozzle D: 1" Low Low Level Indicator (Course #1)

Rn = 0.957/2 = 0.4785 inches tr = 0.1 inches Dp = N/A P = 0.433(0.84)(21.84) = 8 psi tn = 0.179 inches te = N/A h = 0 inches ti = 0 inches

Sn = 23,200 psi tprev = 0.179 inches E = 1 tact = N/A

Minimum Required Thickness Calculation:

trn = PRn = (8)(0.4785) = 0.0002 inches

SE - 0.6P (23,200)(1) - (0.6)(8)

As a conservative approach, let trn=0.1 inches.

The Corrosion Rate Remaining Life Calculations cannot be calculated since thickness measurements cannot be taken on this nozzle. Visual inspection revealed no active corrosion. The remaining life of this nozzle is estimated to be greater than 50 years.

ER-USARMY-FTLEWIS-2

A-14

Nozzle E: 1" Plug (Course #3) d = 1.315 - 2(0.179) = 0.957 inches t = 0.178 inches Y = 9 years Rn = 0.957/2 = 0.4785 inches tr = 0.1 inches Dp = N/A P = 0.433(0.84)(21.84) = 8 psi tn = 0.179 inches te = N/A h = 0 inches ti = 0 inches

Sn = 23,200 psi tprev = 0.179 inches E = 1 tact = N/A

Minimum Required Thickness Calculation:

trn = PRn = (8)(0.4785) = 0.0002 inches

SE - 0.6P (23,200)(1) - (0.6)(8)

As a conservative approach, let trn=0.1 inches.

The Corrosion Rate Remaining Life Calculations cannot be calculated since thickness measurements cannot be taken on this nozzle. Visual inspection revealed no active corrosion. The remaining life of this nozzle is estimated to be greater than 50 years.

ER-USARMY-FTLEWIS-2

A-15

Nozzle F: 1" Plug (Course #3)

Rn = 0.957/2 = 0.4785 inches tr = 0.1 inches Dp = N/A P = 0.433(0.84)(21.84) = 8 psi tn = 0.179 inches te = N/A h = 0 inches ti = 0 inches

Sn = 23,200 psi tprev = 0.179 inches E = 1 tact = N/A

Minimum Required Thickness Calculation:

trn = PRn = (8)(0.4785) = 0.0002 inches

SE - 0.6P (23,200)(1) - (0.6)(8)

As a conservative approach, let trn=0.1 inches.

The Corrosion Rate Remaining Life Calculations cannot be calculated since thickness measurements cannot be taken on this nozzle. Visual inspection revealed no active corrosion. The remaining life of this nozzle is estimated to be greater than 50 years.

ER-USARMY-FTLEWIS-2

A-16

Nozzle G: 1" High High Level Alarm (Course #3)

Rn = 0.957/2 = 0.4785 inches tr = 0.1 inches Dp = N/A P = 0.433(0.84)(21.84) = 8 psi tn = 0.179 inches te = N/A h = 0 inches ti = 0 inches

Sn = 23,200 psi tprev = 0.179 inches E = 1 tact = N/A

Minimum Required Thickness Calculation:

trn = PRn = (8)(0.4785) = 0.0002 inches

SE - 0.6P (23,200)(1) - (0.6)(8)

As a conservative approach, let trn=0.1 inches.

The Corrosion Rate Remaining Life Calculations cannot be calculated since thickness measurements cannot be taken on this nozzle. Visual inspection revealed no active corrosion. The remaining life of this nozzle is estimated to be greater than 50 years.

ER-USARMY-FTLEWIS-2

A-17

Nozzle H: 1" High Level Alarm (Course #3)

Rn = 0.957/2 = 0.4785 inches tr = 0.1 inches Dp = N/A P = 0.433(0.84)(21.84) = 8 psi tn = 0.179 inches te = N/A h = 0 inches ti = 0 inches

Sn = 23,200 psi tprev = 0.179 inches E = 1 tact = N/A

Minimum Required Thickness Calculation:

trn = PRn = (8)(0.4785) = 0.0002 inches

SE - 0.6P (23,200)(1) - (0.6)(8)

As a conservative approach, let trn=0.1 inches.

The Corrosion Rate Remaining Life Calculations cannot be calculated since thickness measurements cannot be taken on this nozzle. Visual inspection revealed no active corrosion. The remaining life of this nozzle is estimated to be greater than 50 years.

ER-USARMY-FTLEWIS-2

A-18

Nozzle I: 4" Firefighting Foam Line (Course #3) d = 4.5 - 2(0.337) = 3.826 inches t = 0.178 inches Y = 9 years Rn = 3.826/2 = 1.913 inches tr = 0.1 inches Dp = N/A P = 0.433(0.84)(21.84) = 8 psi tn = 0.337 inches te = N/A h = 0 inches ti = 0 inches

Sn = 23,200 psi tprev = 0.337 inches E = 1 tact = N/A

Minimum Required Thickness…