Attachment I ROB-FY15-FAC 4311-Tank 29-FINAL_Redacted.pdf

TANK 4311 (TANK 29)

API 653 IN-SERVICE INSPECTION REPORT

Robins AFB, Georgia

A/E Contract No. W9128F-12-D-0006; Delivery Order No. 0006

Submitted to:

U.S. Army Corps of Engineers Omaha District

1616 Capital Avenue; Omaha, NE 68102

6 May 2015

Submitted by:

1011 Boulder Springs Drive, Suite 200; Richmond, Virginia 23225 Phone: 804.592.3900 Fax: 804.592.3901 www.brockenbrough.com Job No. 14-101.11

Austin Brockenbrough & Associates, LLP | Est. 1955

1011 Boulder Springs Drive, Suite 200 | Richmond, Virginia 23225 | 804.592.3900 main | 804.592.3901 fax www.brockenbrough.com

Adam Ashton

U.S. Army Corps of Engineers

Omaha District

1616 Capital Avenue

Omaha, Nebraska, 68102

Re: Inspection Report – Tank 4311 (Tank 29), Robins AFB, GA

USACE Omaha Contract No. W9128F-12-D-0006 D.O. 0006

Brockenbrough Job No. 14-101.11 API 653 In-service Tank Inspections

Various CONUS Locations

Dear Mr. Ashton:

On March 25th, 2015, personnel from Austin Brockenbrough & Associates, LLP

(Brockenbrough) performed an API 653 In-service (visual external) Inspection of Tank 4311

(AKA Tank 29) located at Robins Air Force Base, Georgia. The In-service Inspection of the nominal 10,000 bbl, 43 feet and 6 inches in diameter by 42 feet and 3 inches tall, F-24 (Jet-AA), aboveground vertical storage tank was performed in accordance with API Standard 653, “Tank

Inspection, Repair, Alteration, and Reconstruction,” and the referenced contract. The confined space between the internal floating roof and the fixed roof was not entered during the inspection.

All observations made during this In-service (visual external) Inspection were made from the exterior of the tank.

The tank’s data plate indicates the tank was built in 1995. Leak detection is provided by tracer ports projecting through the tank’s ringwall foundation. Contrary to previous inspection reports, base personnel indicated that while there is a liner under the tank bottom, the tank has no cathodic protection system. The tank’s roof is accessible by a circumferential stairway mounted on the shell of the tank. As-built drawings of the original construction were not available at the time of the inspection. The tank underwent repairs and upgrades in 2009. The stencil on the tank shell and shell manhole cover and the completion report indicate the tank was last cleaned and inspected in April of 2009.

Jet-AA fuel is received into the 10,000 bbl tank from bulk via an underground pipeline through the facility’s filter/separators and is issued from the tank through filters/separators to a truck fillstand and a hydrant system.

A list of the tank’s general construction features is included on page 2.

The results of the inspection are included with the Tank In-Service Inspection Checklist starting on page 8. A checkmark beside an item indicates it was examined and no deficiency was noted.

An “X” beside a checklist item indicates a deficiency and a comment/note is made. During this evaluation, the tank was found to be in a generally good and acceptable condition. There were several anomalies or deficiencies noted, most of which are included on the checklist. These deficiencies, and recommendations for addressing them, are noted below in no particular order:

1. Standing water and debris on top of the concrete ringwall is retained due to conduit resting directly on the top of the wall. See Photograph #1 on page 15. The accumulation of water has contributed to some algae growth and conduit corrosion. If left unattended, the tank bottom to ringwall seal could be at risk of deterioration. The following actions should be taken to correct these deficiencies:

Replace the corroded conduits and have them hung from the tank shell or off of the ringwall.

Estimated construction cost is

2. Excessive lengths of conduit mounting channel are left on the tank shell around the perimeter. The majority of the channels are not used to support any conduit. The following action should be taken to correct this deficiency:

Remove the mounting channel not being used to support tank conduits and spot repair the shell coating.

Estimated construction cost is

3. Some isolated coating failure on the tank bottom extension, anchor chairs, anchor bolts, and tank shell was observed. Due to the coating failure, corrosion of said parts was also observed. Algae and dirt buildup has also taken place in these areas. See Photograph #1 on page 15. The following actions should be taken to correct these deficiencies:

a) Power wash the tank foundation, the exterior of the tank and the tank appurtenances to remove algae and dirt buildup.

b) Spot repair the areas where coating failure and corrosion exists on the bottom extension, anchor chair assemblies, anchor bolts, and tank shell.

Estimated construction cost is

4. Overall, the tank bottom-to-foundation seal is in good shape, however, it has failed in a couple of small areas. See Photograph #2 on page 15. In order to prevent further deterioration, these areas should be addressed. The following action should be taken to correct this deficiency:

Spot repair the tank bottom-to-foundation seal.

Estimated construction cost is

5. Most of the tank piping, flanges, and valves are showing coating failure and corrosion. The

AFFF piping that runs up the side of the tank and around the top is experiencing heavy coating failure and corrosion. The low, low-low, high, and high-high level alarms also display coating failure and corrosion. The following action should be taken to correct this deficiency:

Repair the coating failure and corrosion on the AFFF piping and the level alarms.

Estimated construction cost is

6. The mechanical tape gauge read 18’-3 1/2" while the ATG read 17’-9 5/16” at the time of inspection. The mechanical tape gauge is inaccurate by more than what is acceptable. The following action should be taken to correct this deficiency:

Recalibrate the tape gauge.

Estimated construction cost is

7. There are areas of general and localized coating failure and surface corrosion on the tank roof, roof nozzles, roof handrails, the circumferential stairway handrails and stair treads, and platform deck plates. Some of these areas appear to be caused by standing water that is occurring because of flat/sagging spots in the stairway deck plate and sagging of the roof plate. Standing water on tank roofs can accelerate coating failure and create corrosion on the roof plates. Dirt and algae are also accumulating due to the ponding of water. See

Photographs #3 through #7 on pages 16 through 18. The lack of roof drainage is believed to be the result of non-compliant construction. The roof rafter spacing exceeds the API 650 limits, even for the time when the tank was constructed. The following actions should be taken to correct these deficiencies:

a) Provide drain holes through the stairway landing deck plates and spot repair the coating.

b) Power wash and spot repair the areas of coating failure on the exterior of the tank roof, the roof nozzles, and the circumferential stairway.

c) Apply an algae/mold inhibitor to the exterior of the tank.

d) Routinely monitor and inspect areas of the roof where water ponds for coating failure and corrosion.

e) Alternatively, the roof and its support structure should be replaced to meet API 650 requirements.

Estimated construction cost, based on replacement of the roof, is

8. The four roof-mounted circulation vents/inspection hatches all have coating failure and corrosion on the vents, locking pins, and pivot pins. See Photograph #8 on page 18. The following action should occur to correct this deficiency:

Repair the coating failure and corrosion on the roof-mounted vents.

Estimated construction cost is

9. The roof perimeter handrails terminate at either side of all of the roof perimeter vent/inspection hatches, leaving the space above the hatches unguarded. This discontinuation of the guardrail is non-OSHA compliant and is a hazard to anyone accessing the roof. The following action should be taken to correct this deficiency:

Install continuous top rails and middle rail safety chains in all guardrail openings at the roof perimeter vent/inspection hatches.

Estimated construction cost is

10. The water draw-off system piping and tank nozzle are threaded. Military standards do not allow threaded piping or nozzles to be used. Also, the tank isolation valve is a ball valve.

Military standards require tank isolation valves to be double block and bleed valves. The following actions should be taken to correct these deficiencies:

At the next out-of-service inspection:

a) Replace the threaded water draw-off nozzle with a flanged nozzle.

b) Replace water draw-off system tank isolation valve with a double block and bleed isolation valve.

c) Replace the threaded pipe with welded pipe and flanged valves and equipment.

Estimated construction cost is .

11. The thermal relief valve assembly installed on the tank issue piping is constructed of threaded pipe. UFC 3-460-01 states to “use threaded connections only where unavoidable…” The thermal relief valve assembly also does not have testing tees as required by the UFC. The thermal relief assemblies also contain sight flow indicators. Sight flow indicators are known leak points and are prohibited on thermal relief piping per the UFC.

The following actions should be taken to correct these deficiencies:

a) Remove the sight flow indicators from the thermal relief piping.

b) At the next out-of-service inspection, provide welded or flanged connections and testing tees on the thermal relief piping.

Estimated construction cost is

12. The rise of the circumferential stairway measures approximately 8 3/4" to 9”. However, the distance from the concrete containment slab to the top of the lowest stair tread measures approximately 18". OSHA requires a consistent rise and run over the entire stairway. The following action should be taken to correct this deficiency:

Install landing at approximately 8 3/4" above slab to act as a new bottom tread.

Estimated construction cost is

13. It appears the ATG well was once used as the sample gauge well, but was then repurposed to house the ATG and water and temperature probe. Per DoD Standard Design AW 78-24-27, a sample gauge well is required. Base personnel are currently performing manual gauging of the tank through the ATG gauge well. This operation can cause excessive wear and damage to the ATG system. The following action should be taken to correct this deficiency:

Install a new sample gauge well per DoD Standard Design AW 78-24-27.

Estimated construction cost is

14. The sump on this tank is located in the center under the center roof vent. This prevents the installation of a temperature/water probe per standards. The existing ATG well is being used for this purpose, however, this well should be slotted. No slots were observed at the time of inspection. The following action should be taken to correct this deficiency:

At the next out-of-service inspection, slot the well with properly sized slots to meet requirements.

Estimated construction cost is

15. The control valve on the receipt line is aluminum. Aluminum control valves are not allowed by NFPA. The following action should be taken to correct this deficiency:

At the next out-of-service inspection, replace the control valve with either a carbon steel or ductile iron control valve.

Estimated construction cost is

16. The secondary containment area is in good shape with some minor places of deterioration.

However, the joint seals in the slab and the walls are failing. The seal between the containment slab and the tank foundation has also begun to fail. The following actions should be taken to correct these deficiencies:

According to facility personnel, a plan is already in place to repair the failed joint seals throughout the secondary containment.

Estimated construction cost is

17. The low manhole reinforcing plate’s weep hole is sealed with tank coating. See Photograph

# 9 on page 19. The holes are used to leak detection at the welds of the manhole. The following action should be taken to correct this deficiency:

Remove coating from the inside of the weep hole.

Estimated construction cost is

All repairs and modifications should be performed in accordance with API 653, UFC 3-460-01, DoD Standard Design AW 78-24-27, and applicable UFGS specifications.

The estimated construction costs noted above are based upon all of the work being performed under a single construction contract. The costs do not include any special conditions or prime contractor markup that might be applicable, but they do include the cost of any coating repairs that would be required due to the contractor’s work.

TANK INSPECTION, REPAIR, ALTERATION, AND RECONSTRUCTION

Tank In-service Inspection Checklist

Item Completed Comments

C.1.1 Foundation

Measure foundation levelness and bottom elevations (see Annex B for extent of measurements). See notes.

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 water-draw 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 See notes.

e) Check for settlement around perimeter of tank.

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.

NA

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. NA

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 (ultrasonic, hammer testing, or turning of coupons) when the tank is out of service.

NA

C.1.1.5 Site Drainage

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

b) Check operating condition of the dike drains.

C.1.1.6 Housekeeping

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

C.1.1.7 Cathodic Protection

Review cathodic protection potential readings. X See notes.

C.1.2 Shells

C.1.2.1 External Visual Inspection

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

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

X See notes.

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

C.1.2.2 Internal (Floating Roof Tank)

Visually inspect for grooving , corrosion, pitting, and coating failures NA

C.1.2.3 Riveted Shell Inspection

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

b) Locate leaks by sketch or photo (location will be lost when shell is abrasive cleaned for painting). NA

c) Inspect rivets for corrosion loss and wear. NA

d) Inspect vertical seams to see if they have been full fillet lap-welded to increase joint efficiency. NA

Tank In-service Inspection Checklist (Continued)

e) If no record exists of vertical riveted seams, dimension and sketch (or photograph) the rivet pattern: number of rows, rivet size, pitch length, and note whether the joint is butt-riveted or lap-riveted.

C.1.2.4 Wind Girder (Floating Roof Tanks)

a) Inspect wind girder and handrail for corrosion damage (paint failure, pitting, corrosion, product buildup), especially where it occurs at tack-welded junction, and for broken welds.

NA

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

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

C.1.3 Shell Appurtenances

C.1.3.1 Manholes and Nozzles

a) Inspect for cracks or signs of leakage on weld joint at nozzles, manholes, and reinforcing plates.

b) Inspect for shell plate dimpling around nozzles, caused by excessive pipe deflection.

c) Inspect for flange leaks and leaks around bolting.

d) Inspect sealing of insulation around manholes and nozzles. NA

e) Check for inadequate manhole flange and cover thickness on mixer manholes. NA

C.1.3.2 Tank Piping Manifolds

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

b) Inspect firefighting system components. X See notes.

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 the tank. X See notes.

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

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

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

h) Check welds on shell-mounted davit clips above valves 6 inches and larger. NA

C.1.3.3 Autogauge System

a) Inspect autogauge tape guide and lower sheave housing (floating swings) for leaks.

b) Inspect autogauge head for damage.

c) Bump he checker on autogauge head for proper movement of tape.

d) Identify size and construction material of autogauge tape guide (floating roof tanks). No access.

e) Ask operator if tape tends to hang up during tank roof movement (floating roof tanks).

f) Compare actual product level to the reading on the autogauge (maximum variation is 2 in.). X See notes.

g) On floating roof tanks, when the roof is in the lowest position, check that no more than two ft of tape are exposed at the end of the tape guide. No access.

h) Inspect condition of board and legibility of board-type autogauges. NA

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

C.1.3.4 Shell-mounted Sample Station

a) Inspect sample lines for function of valves and plugging of lines, including drain or return-to-tank line. NA

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

c) Test bracing and supports for sample tines and equipment. NA

C.1.3.5 Heater (Shell Manhole Mounted)

Inspect condensate drain for presence of oil indicating leakage. NA

C.1.3.6 Mixer

a) Inspect for proper mounting flange and support. NA

b) Inspect for leakage. NA

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

C.1.3.7 Swing Lines: Winch Operation

a) Nonfloating. Raise, then lower the swing line with the winch, and check for cable lightness 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 light, 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 show the opposite.

NA

C.1.3.8 Swing Lines: External Guide System

Check for leaks at threaded and flanged joints NA

C.1.3.9 Swing Lines: Identify Ballast Varying Need

Check for significant difference in stock specific gravity. NA

C.1.3.10 Swing Lines: Cable Material and Condition

a) For nonstainless steel cable, check for corrosion over entire length. NA

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

C.1.3.11 Swing Lines: Product Sample Comparison

Check for water or gravity differences that would indicate a leaking swing joint. NA

C.1.3.12 Swing Lines: Target

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

NA

C.1.4 Roofs

C.1.4.1 Deck Plate Internal Corrosion

For safety, before accessing the roof, check with ultrasonic instrument or lightly use a ball peen hammer to test the deck plate near the edge of the roof for thinning. (Corrosion normally attacks the deck plate at the edge of a fixed roof and at the rafters in the center of the roof first.)

C.1.4.2 Deck Plate External Corrosion

Visually inspect for paint failure, holes, pitting, and corrosion product on roof deck. X See notes.

C.1.4.3 Roof Deck Drainage

Look for indication of standing water. (Significant sagging of fixed roof deck indicates potential rafter failure. Large standing water areas on a floating roof indicate inadequate drainage design or, if to one side, a nonlevel roof with poss ble leaking pontoons.)

X See notes.

C.1.4.4 Level of Floating Roof

At several locations, measure distance (inches) from floating roof rim to the horizontal weld seam above the roof or fixed roof inspection hatch openings. A variance in the readings indicates a non-level roof with poss ble shell out-of-round, out-of-plumb, leaking pontoons, or hang-up. On small diameter tanks, an un-level 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, Readings could indicate a leaking roof, leaking seal system, or inadequate ventilation of the area above the internal floating roof.

2.4 ppm VOC on pan.

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. NA

c) Remove small test sections of insulation and check roof plate 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 the full roof circumference at the level of inspection. NOTE Inspection of the seal and measurement of the rim spaces and seal-to-shell gaps at more than one level may be necessary to more fully determine if any problems exist at other levels of tank operation).

No access.

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

1) ______ Opposite pair 1.

2) Opposite pair 2.

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

No access.

d) Inspect fabric for deterioration, holes, tears, and cracks. No access.

e) Inspect visible metallic parts for corrosion and wear No access.

f) Inspect for openings in seals that would permit vapor emissions. No access.

g) Inspect for protruding bolt or rivet heads against the shell. No access.

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.

No access.

j) Inspect wedge-type wiper seals for flex bility, resilience, cracks, and tears. No access.

C.1.5 Roof Appurtenances

C.1.5.1 Sample Hatch

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

b) On tanks governed by Air Quality Monitoring District rules, check for the condition of seal inside hatch cover.

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

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. NA

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

g) Test operation of system. No access.

h) On ultra clean stocks such as JP4, check for presence and condition of protective coating or liner inside sample hatch (preventing rust from pipe getting into sample).

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 a hold-off distance marker and tab with a hold-off distance (leg ble). X See notes.

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 well 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.

NA

C.1.5.3 Fixed Roof Scaffold Support

Inspect scaffold support for corrosion, wear and structural soundess. NA

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

a) Check the hatch for corrosion and missing bolts.

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

C.1.5.5 Autogauge: Float Well Cover

a) Inspect for corrosion. No access.

b) Check tape cable for wear or fraying caused by rubbing on the cover. No access.

C.1.5.6 Sample Hatch (Internal Floating Roof)

a) Check overall conditions. No access.

b) When equipped with a fabric seal, check for automatic sealing after sampling. No access.

c) When equipped with a recoil reel opening device, check for proper operations. No access.

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

Check condition of screens, locking and pivot pins. X See notes.

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 10 and that fabric seal Is above the liquid level.

NA

C.1.5.10 Removable Roof Leg Racks

Check for leg racks on roof. NA

C.1.5.11 Vacuum Breakers

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

No access.

C.1.5.12 Rim Vents

a) Check condition of the screen on the rim vent cover. No access.

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

NA

C.1.5.13 Pontoon Inspection Hatches

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

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

c) If pontoon hatches are equipped with locked down coves, check for vent tubes.

Check that vent tubes are not plugged up. Inspect lock-down devices for condition and operation.

NA

C.1.6 Accessways (See Tank Out-of-service Inspection Checklist, Item C.2.12.)

C.2.12 Access Structures

C.2.12.1 Handrails

a) Identify and report type (steel pipe, galvanized pipe, square tube, angle) and size of handrails. See notes.

b) Inspect for pitting and holes, paint failure. X See notes.

c) Inspect attachment welds.

d) Identify cold joints and sharp edges. Inspect the handrails and mid-rails.

e) Inspect safety drop bar (or safety chain) for corrosion, functioning, and length. X See notes.

f) Inspect the handrail between the rolling ladder and the gauging platform for a hazardous opening when the floating roof is at its lowest level.

NA

C.2.12.2 Platform Frame

a) Inspect frame for corrosion and paint failure.

b) Inspect the attachment of frame to supports and supports to tank for corrosion and weld failure.

c) Check reinforcing pads where supports are attached to shell or roof.

d) Inspect the surface that deck plate or grating rests on, for thinning and holes.

e) Check that flat surface–to-flat surface junctures are seal-welded.

C.2.12.3 Deck Plate and Grating

a) Inspect deck plate for corrosion-caused thinning or holes (not drain holes) and paint failure X See notes.

b) Inspect plate-to-frame weld for rust scale buildup.

c) Inspect grating for corrosion-caused thinning of bars and failure of welds. NA

d) Check grating tie down clips. Where grating has been retrofitted to replace plate, measure the rise of the step below and above the grating surface and compare with other risers on the stairway.

NA

C.2.12.4 Stairway Stringers

a) Inspect spiral stairway stringers for corrosion, paint failure, and weld failure. X See notes.

b) Inspect stairway supports to shell welds and reinforcing pads. No repads.

c) Inspect steel support attachment to concrete base for corrosion. NA

C.2.12.5 Rolling Ladder

a) Inspect rolling ladder stringers for corrosion. NA

b) Identify and inspect ladder fixed rungs (square bar, round bar, angles) for weld attachment to stringers and corrosion, particularly where angle rungs are welded to stringers.

NA

c) Check for wear and corrosion where rolling ladder attaches to gauging platform. NA

d) Inspect pivot bar for wear and that it is secure. NA

e) Inspect operation of self-leveling stairway treads. NA

f) Inspect for corrosion and wear on moving parts. NA

g) Inspect rolling ladder wheels for freedom of movement, flat spots, and wear on axle. NA

h) Inspect alignment of rolling ladder with roof rack. NA

i) Inspect top surface of rolling ladder track for wear by wheels to assure at least 18 in. of unworn track (track long enough).

NA

j) Inspect rolling ladder track welds for corrosion. NA

k) Inspect track supports on roof for reinforcing pads seal-welded to deck plate. NA

l) Check by dimensioning, the maximum angle of the rolling ladder when the roof is on low legs.

Max. angle .

m) If rolling ladder track extends to within 5 ft of the edge of the roof on the far side, check for a handrail on the top of the shell on that side.

NOTES:

C.1.1 The foundation measurements indicate the tank is relatively level and with no appreciable out-of-plane deflection. No limit of planer tilt is stated in API 653. The distance measured from the tank bottom external extension to a horizontal level line at 8 equal distant locations were: 52 9/16” (origin), 52 12/16”, 52 10/16", 52 8/16", 52 9/16”, 52 9/16”, 52 8/16” 52 7/16” (low point),, and 52 9/16” (origin). The tank measures level to within 3/16” in 43’-6”.

Calculations evaluating the shell settlement are attached.

C.1.1.1.d) Some areas of standing water on ring helped by conduit running along top of ringwall.

C.1.1.7 No means of cathodic protection in place. Only thing mentioned by base personnel is a liner under the tank bottom.

C.1.2.1.a) Coating failure and minor surface corrosion on a few localized locations on lower shell course.

C.1.2.1.b) Coating failure and minor surface corrosion on a few localized locations on chime.

C.1.2.1.c) Bottom-to-foundation seal has failed in a few areas around tank, and some algae growth on the seal.

Conduit routed on top of ringwall collecting debris near chime.

C.1.3.2.b) Coating failure and surface corrosion on AFFF piping, fuel piping, and equipment.

C.1.3.2.d) Thermal relief valves lack testing tees. Thermal relief valve assemblies have sight flow indicators.

Threaded thermal relief piping.

C.1.3.3.f) Tape Reading = 18’-3 1/2”; ATG = 17’-9 5/16”.

C.1.4.2 Coating failure and surface corrosion in several locations on tank roof.

C.1.4.3 Numerous area of water ponding on roof. Minor corrosion present at some of these locations.

C.1.4.4 Floating pan too low to measure from roof.

C.1.5.1.a) No sample hatch with stilling well.

C.1.5.2.a) Internal and external corrosion on spool piece. No slots in well.

C.1.5.2.b) No hold-off distance marked.

C.1.5.7 Coating failure and corrosion on all (4) vents, locking pins, and pivot pins.

C.2.12.1.a) 3”x3” angle handrails.

C.2.12.1.b) Minor coating failure and corrosion on handrails at stairs and on roof.

C.2.12.1.e) No OSHA compliant safety chains/drop bar at roof vents.

C.2.12.3.a) Coating failure and surface corrosion on low platform. Water is ponding on platform.

C.2.12.4.a) Coating failure underneath stair treads near top of tank.

ADDITIONAL NOTES:

Aluminum control valve on receipt line.

Level switch assembly is constructed with threaded pipe.

Water draw-off piping and nozzle are threaded. Water draw-off tank nozzle is 3/4" and is a ball valve.

Containment slab to foundation seal failed around entire tank with light vegetation growth.

Dike floor and dike wall joint seals failed.

Mold and algae growth on tank and around appurtenances.

Access stairs over pipes and walls have coating failure and corrosion.

Conduit running along top of concrete ringwall.

Anchor bolt coating failure and corrosion.

Another anchor plate and weld crosses shell vertical weld.

Non-OSHA compliant first step on circumferential stair. Average rise = 8 3/4"-9”, Bottom rise = 18”

Non-OSHA compliant handrails on roof. Openings at roof-mounted vents.

(2) control valve tubing supports have come unattached from tank shell.

Weep hole on reinforcing plate for lower manhole on northwest side of tank is sealed with coating.

Photograph #1 – Conduit Resting on Ringwall

Corroded conduit preventing drainage from ringwall. Coating failure and algae and dirt buildup on the bottom plate extension.

Photograph #2 – Bottom-to-foundation Seal

Seal failure around tank bottom.

Photograph #3 – Tank Roof Isolated coating failures and surface corrosion on roof plates.

Photograph #4 – Stair Platform

General coating failure and surface corrosion on platform deck plate.

Photograph #5 – Tank Roof Plate

General coating failure and surface corrosion on tank roof at areas of standing water.

Photograph #6 – Tank Roof Plate

Coating failure and surface corrosion on roof plate.

Photograph #7 – Standing Water on Tank Roof

Standing water and algae/dirt buildup at several locations on the tank roof were observed.

Photograph #8 – Roof-mounted Vent

Coating failure and corrosion on roof-mounted vents.

Photograph #9 – Manhole Reinforcing Plate Weep Hole

Coating filling the weep hole rendering the hole inadequate.

g:\14 jobs\14-101 api 653 in-service inspections\14-101.11 api 653 inspections - robins afb\general\reports\final\tank 4311 (29)\report letter -tank 4310 (29) robins afb.docx

While this In-Service (visual external) Inspection found no problems requiring immediate repair and the accessible areas of the tank appear suitable for continued use in its current service, there are some deficiencies that are contrary to API 650, NFPA 30, and OSHA. These deficiencies should be addressed in a timely manner.

According to the previous inspection report, the last out-of-service was performed in April of

2009, and the next out-of-service inspection should be performed within 10 years of the date

(April 2019). The next API Standard 653 In-Service (visual external) Inspection should be performed by an API 653 Inspector by March 2020. The UFC 3-460-03 requires aboveground storage tanks to be inspected every 10 years, therefore, the in-service inspection may be performed in conjunction with the next out-of-service inspection.

The Out-of-Service (internal) Inspection should include external visual inspection with shell

UTMs, and an examination of the tank bottom by magnetic flux leakage (MFL or MFE) technology.

The Out-of-Service Inspection should include a thorough code compliance evaluation. The code compliance evaluation should include 29 CFR Part 1910.106, Occupational Safety and Health

Standards – Flammable and Combustible Liquids; 29 CFR Part 1910 Subpart D, Occupational

Safety and Health Standards – Walking-Working Surfaces; 40 CFR Part 112, Oil Pollution

Prevention; NFPA 30, Flammable and Combustible Liquids Code; and UFC 3-460-01, Design:

Petroleum Fuel Facilities.

Please contact us if you have any questions or need more information.

Sincerely, Austin Brockenbrough & Associates, LLP

Andrew Swenck, PE

Structural Engineer

API 653 Inspector No. 56234

Enclosure – Tank 4311 – Shell Settlement Evaluation

Austin Brockenbrough & Associates, L.L.P. Job No. 14-101.11

Job Title: Robins AFB Date: 4/7/2015

Subject: Tank 4311 - Shell Settlement Evaluation By: Andrew Swenck

API 653 Appendix B

Optimum cosine curve, B 2.2.4.e) Z = a + b x cos(theta + c)

Diameter (D) = 43.5 (ft)

Number of equally spaced data points (ft)= 8

L = Arc length between measurement points (ft) = 17.08

Tank Height (H) = 42.3 (ft)

* Z U S

0 52.44 0.00 0.06 0.06 0.08

1 52.56 0.13 0.08 -0.05 0.02

2 52.75 0.31 0.12 -0.20 -0.16

3 52.63 0.19 0.15 -0.03 0.01

4 52.50 0.06 0.17 0.11 0.11

5 52.56 0.13 0.15 0.03 -0.02

6 52.56 0.13 0.12 -0.01 -0.03

7 52.50 0.06 0.08 0.02 -0.01

8 52.44 0.00 0.06 0.06 0.08

Maximum out-of -plane deflection = -0.16

* = measured elevation

Z = calculated ridged body tilt (in)

U = out-of-plane settlement =

S = out-of-plane deflection z-y

Y = yield sterength of shell material (PSI) = 30,000

E = Youngs modulas of elasticity (lbf/in2) = 29*10^6

S allowable (in) (API 653 B.3.2.1) = (L^2*Y*11)/(2EH)*12 = 0.47 in

R^2 = (Syy - SSE) / Syy 0.2 not >=0.9 therefore cosine curve is invalid.

Evaluation by the Arc Length Method is required.