Addendum #1 Appendix F

West Banks Elevated Tank – December 2017 1

WEST BANKS MILL

500,000 Gallon Elevated Tank

West Banks Elevated Tank – December 2017 2

I. Introduction

On December 5, 2017 the West Banks Mill Tank was taken out of service, cleaned, and a complete interior and exterior inspection was performed. Once the inspection was complete, the tank was disinfected in accordance with AWWA recommendations and put back into service. The following is a summary of the inspection. Also included in the inspection report is a list of recommended rehabilitation work, a construction cost estimate, historical maintenance records, and a recommended maintenance ranking compared to other water storage tanks in the Douglasville – Douglas County Water and Sewer Authority (DDCWSA) water system.

II. General B. 500,000 gallon elevated tank

C. Welded steel construction

D. Located on West Banks Mill Road 0.04 miles east of the intersection of Tyree

Road and West Banks Mill Road.

E. Elevated torospherical bowl supported by six (6) welded steel columns with tie rods.

F. 60 inch diameter welded steel riser

G. Concrete pedestal foundations

III. Observations

A. Exterior Coating

The coating on the exterior of the tank is generally in good condition. Adhesion of all layers of the coating system, inter-coat and substrate, appeared to be excellent on the riser and columns. Adhesion on the tank bowl appeared to be excellent between the steel, prime coat, and intermediate coat. The adhesion of the finish coat on the bowl appeared to be poor.

The coating system on the bowl around the balcony had an average dry film thickness of 16.7 mils. Most of the exterior of the tank/support columns had a thin layer of mildew growth and the protective coatings are chalking (deterioration of epoxy binder). The exterior coating exhibited a few areas of coating failure, mostly limited to the lower portions of the column legs and column anchor plates. Several areas of the tank appeared to have a secondary coating covering up areas of graffiti.

B. Column Foundations and Anchor Bolts

All six (6) of the tank column foundations were inspected. Concrete foundations appeared to be in good condition, with the exception to minor spalling on Column 5. Minor

West Banks Elevated Tank – December 2017 3 corrosion was observed at the interface of the column anchor plate and the grout bearing pad in several locations. Tie rods and turnbuckles were observed and appeared to be in good condition, with the exception of light mildew along their length and minor corrosion at rub points where the tie rods cross.

C. Interior Coating

The interior coating system is generally in excellent condition with less than five (5) locations of spot corrosion on the floor. Coating thickness was tested resulting in an average measured thickness of 15.0 mils. The coating on the interior of the riser appeared to be in good condition. Coating adhesion on the tank interior appeared to be excellent between all layers. One area was observed to be experiencing minor pitting (approximately 1/16” deep) and was repaired with Aquatapoxy prior to disinfection.

D. Exterior Accessories

The tank is equipped with a column ladder and fixed bowl ladder. The column ladder extends to the outside edge of the tank balcony and is structurally sound. The column ladder is equipped with a cable safety climb system and a lockable ladder shield. SCADA communication cables/conduit are attached to the column ladder and appear to be in good condition. The bowl ladder is also equipped with a cable safety climb system and antenna cables are securely attached to the ladder.

The tank bowl balcony is 36-inches wide and has a 42-inch tall handrail. The balcony has drainage holes that prevent water from pooling on the balcony; however, there does appear to be a few areas where new drainage holes need to be drilled. Two (2) antennas are mounted to the balcony handrail. One additional antenna is mounted adjacent to the tank vent. Abandoned stainless steel antenna mast anchor plates are located adjacent to the antenna. The tank vent is a round type which is equipped with an insect screen.

The bowl roof hatch is a 30-inch square opening with a hinged and lockable cover.

An additional 24-inch bolted access hatch is located on the roof adjacent to the vent. It is in good condition, but is not equipped with hinges. The tank is not equipped with obstruction lighting.

The riser is equipped with a 24-inch diameter binged, flanged manway. The manway appears to be in good condition with the exception of the corroded bolts.

West Banks Elevated Tank – December 2017 4

E. Interior accessories

The tank bowl is equipped with one interior ladder which is in good condition and is equipped with a rigid rail safety climbing system. A safety grate is installed at the top of the riser and appeared to be in good condition.

The tank riser has a 12-inch inlet/outlet pipe with deflector plate and a drain line.

The piping inside the riser appears to be in good condition. The inlet/outlet pipe is equipped with a removable silt stop assembly and deflector plate that extends 18 inches off the riser floor.

An 8-inch overflow pipe extends up column 3 penetrating the tank balcony and then the sidewall of the tank. The overflow pipe is supported at intervals along its length and discharges on a concrete splash pad on grade. The overflow pipe is equipped with a flap valve and screen.

F. Site

The tank site was clean and well maintained. The tank drain is routed to the southwest corner of the site and discharges via a riser pipe and flap valve approximately 4 feet above grade. The tank eventually drains off into the woods and onto residential property to the east of the tank site. The resident located south of the tank site has mentioned to

DDCWSA personnel that the water runs onto his property from the drain line, but it does not create damage as long as it flows at low volume.

Site fencing is in good condition. There are two (2) locations where a tree has fallen across the site fence. The fence is topped with 3-strand barbed wire. A double leaf gate provides access to the site.

IV. Maintenance Priority

Based on observations described herein, and specifically based on the overall condition of the interior of the tank, the West Banks Mill Tank has been assigned a low ranking on the maintenance priority list.

West Banks Elevated Tank – December 2017 5

V. Recommendations

Rehabilitation recommendations include:

A. Exterior Surfaces

• Pressure wash and overcoat existing tank with an epoxy intermediate coat and urethane finished coat.

• Mechanically clean areas of spot corrosion prior to coating application.

B. Accessories

• Re-route drain line below grade and off site. Daylight the drain line and terminate with flap valve.

• Paint altitude valve vault piping and valves.

• Install a siphon pipe in the tank to facilitate draining the lower portion of the tank bowl.

C. Site

• Remove fallen trees and repair site fence.

VI. Historical Improvements, Repairs and Inspections

Item Date Year Constructed 2003

Washout, cleaning and inspection 2014

Washout, cleaning and inspection 2017

West Banks Elevated Tank – December 2017 6

Figure 1 - Riser Manway

Figure 2 - Electrical Cabinet

West Banks Elevated Tank – December 2017 7

Figure 3 - Column No. 1 with Ladder

Figure 4 – Typical Column Foundation

West Banks Elevated Tank – December 2017 8

Figure 5 – Corrosion at Riser Baseplate

Figure 6 – Damage to Coating on Column

West Banks Elevated Tank – December 2017 9

Figure 7 – Typical Anchor Bolt Connection

Figure 8 – Typical Tie Rod Turn Buckle

West Banks Elevated Tank – December 2017 10

Figure 9 – Corrosion on Tie Rod

Figure 10 - Inlet/Outlet Pipe & Drain Line with Deflector Plates

West Banks Elevated Tank – December 2017 11

Figure 11 – Coating Cracking on Riser

Figure 12 – Column Ladder at Bowl Balcony

West Banks Elevated Tank – December 2017 12

Figure 13 – Exterior Mildew

Figure 14: Corrosion on Tank Balcony Handrail

West Banks Elevated Tank – December 2017 13

Figure 15: Drainage in Balcony Floor

Figure 16: Antenna on Balcony

West Banks Elevated Tank – December 2017 14

Figure 17: Exterior Bowl Ladder w/ Safety Climb

Figure 18: Tank Vent and Antenna

West Banks Elevated Tank – December 2017 15

Figure 19: Antenna Anchor Plates (Not Used)

Figure 20: 30-inch Square Roof Hatch

West Banks Elevated Tank – December 2017 16

Figure 21: Additional 24-inch Diameter Access Hatch

Figure 22: Bowl Ladder, Antenna, and Roof Vent

West Banks Elevated Tank – December 2017 17

Figure 23: Overflow Pipe and Interior Roof Plates

Figure 24: Typical Tank Interior

West Banks Elevated Tank – December 2017 18

Figure 25: Riser Safety Grate

Figure 26: Roof Structure

West Banks Elevated Tank – December 2017 19

Figure 27: Interior Bowl Ladder and Rail Safety Climb

Figure 28: Spot Corrosion on Tank Interior Floor

West Banks Elevated Tank – December 2017 20

Figure 29: Tank Site Looking Southwest

Figure 30: Tank Drain

West Banks Elevated Tank – December 2017 21

Figure 31: Drain w/ Flap Valve and Screen

Figure 32: Tree Damage on Site Fence

West Banks Elevated Tank – December 2017 22

Figure 33: Rain Gauge

Figure 34: Site Entrance

West Banks Elevated Tank – December 2017 23

Figure 35: West Banks Mill Road at Tank Site (looking South)

Figure 36: West Banks Mill Road Tank Site (looking East)

West Banks Elevated Tank – December 2017 24

Figure 37: West Banks Mill Road Tank Site (looking East)

Figure 38: West Banks Mill Road Tank

West Banks Elevated Tank – December 2017 25

END OF REPORT

West Banks Elevated Tank – December 2017 26

THIS PAGE IS INTENTIONALLY LEFT BLANK

APPENDIX A

Construction Cost Estimate

Item No. Quantity Unit Description Unit Cost Total Cost

Exterior

1 19,600 SF Pressure Wash, Spot Prime and Overcoat 3.50$ 68,600$

Interior

1 10,000 SF Abrasive Blast and New Coating System 12.00$ 120,000$

Accessories

1 1 LS Re-route Drain Line and Install Flap Valve 6,500.00$ 6,500$

1 1 LS Paint Altitude Valve Vault Piping and Valves 1,200.00$ 1,200$

1 1 LS Repair Damaged Fence and Remove Fallen Tree 1,500.00$ 1,500$

1 1 LS Interior Bowl Siphon Pipe 4,000.00$ 4,000$

Site

1 1 LS Trim Overgrowth from Fence 250.00$ 250$

Subtotal 202,050$

Bonds and Insurance (2.5%) 5,051$

Mobilization (5%) 10,103$

Construction Contingency (10%) 20,205$

SUBTOTAL 237,409$

Engineering and Inspection (15%) 35,611$

Inflation (5%) 11,870$

OPINION OF TOTAL COST 284,891$

WEST BANKS MILL TANK RECONDITIONING

ENGINEER'S OPINION OF PROBABLE CONSTRUCTION COSTS

APPENDIX B

Field Inspection Report

17037

12/5/2017

Cloudy, 60

9273 West Banks Mill

Rd.

50'

Ht. to Bottom 121'

Ht. to Overflow 158'

Construction Welded Steel

Column 4: Appears to have graffiti painted over, minor chipping of protective coating on base plate, slight mildew growth, small areas of spot corrosion on column; Overall good condition

Column 5: Appears to have graffiti painted over, minor chipping of protective coating on base plate, slight mildew growth, small areas of spot corrosion on column, minor spalling of concrete on foundation;

Overall good condition

Column 6: Appears to have graffiti painted over (major cracking of top coat), minor chipping on column, slight mildew growth; Overall good condition

Tie Rod/Turnbuckle Condition: Minor mildew growth, overall in good condition. Minor corrosion at rub points where tie rods cross.

Miscellaneous Comments: Additional security measures include ladder shield and bottom section of ladder removed. Concrete spalling on foundation corner of Column 5.

Column Ladder

Ladder Location: Column 1, Communication cables are attached to the ladder

SUPPORT COLUMN(S)

Number of Columns/Legs: 6

Coating Condition (Location and Millage): Coating Thickness: 8.4 - 17.5 mils, Avg. 13.5 mils, Intercoat adhesion is good; Coating adhesion to steel substrate is excellent. Good condition w/ only a few areas of small areas of coating failure.

Column 1: Access Ladder, Slight mildew growth, Conduit attached to back of ladder, Spot corrrosion on tie rod anchor tabs and small area of column; Overall good condition

Column 2: Slight mildew growth, Slight spot corrosion on tie rod anchor tabs and small location on column. Overall good condition

Column 3: Minor chipping to protective coating on base plate, slight mildew growth, amall areas of spot corrosion on column, supplemental grounding system attached to column, overall good condition.

Overflow pipe connected to leg with welded tabs, splash pad at bottom.

Foundation/Base Plate/Anchor Bolt Condition

Zone 1402

Elevated Leg

1402.00'

500,000 Gallons

Safety System: Cable climbing system

Rung Spacing: 12" Ladder Width: 16"

Capacity

Contractor

Serial Number

Erected (Date)

TANK INSPECTION FIELD REPORT

ELEVATED WATER TANK

Weather:

Address:

NAMEPLATE INFORMATION

Water System:

Tank Name:

Press. System:

Type:

Datum:

Krebs Job No:

Date:

Diameter

S 5331

Caldwell Tanks, Inc.

DDCWSA

West Banks Mill

Riser Foundation/Base Plate/Anchor Bolt Condition: Concrete and grout foundation excellent condition;

Minor corrossion on base plate where coating has failed; Anchor bolts are in good condition

Riser Manway

Miscellaneous Appurtenances(Antennas, Safety Devices): One antenna at vent and additional base plates which are not in use

Coating Condition (Location and Millage): Good condition; Coating Thickness 10.7 - 23.8 mils, Avg. 16.7 mils on sides of bowl; Coating Thickness 10.7 - 24.9 mils, Avg. 15.2 mils on top of bowl. Coating failure exhibited on balcony handrail at numerous locations. Minor chalking over most of the tank

Level Indicator Assembly

Type: None Operational:

Type: None Operational:

Obstruction Lighting

Roof Vent

Type: Round Vent Insect Screening: Yes

Size: 42" diameter Top, 30" diameter neck

Fixed/Rotating: Fixed

Safety System: Cable climbing system

Rung Spacing: 12" Ladder Width: 16"

Roof Hatch

Size: 30" Square Hinged: Yes Lockable: Yes

Riser Diameter: 60"

4" Raised Curb Surrounding Opening: Yes 2" Overhang on Hatch Cover: Yes

Balcony

Width: 36"

Positive Drainage: Yes

Handrail Height: 42"

Bowl Ladder

Bowl General Condition: Generally in good condition, minor chalking, place on bowl where graffiti coverup coating was applied, mildew present

BOWL, EXTERIOR

Riser Ladder

Safety System: Rail climbing system Ladder Width: 16"

Rung Spacing: 12"

Coating Condition (Location and Millage): Good condition, small spot failure on manway and coating cracking on column near manway penetration. Coating Thickness: 11.9 - 20.1 mils, Avg. 15.4 mils, Intercoat adhesion is good, Coating adhesion to steel substrate excellent.

Miscellaneous Comments: 8" drain connection with 5" non-removable silt stop and deflector plate

Opening Size: 24" diameter

Type (Hinged/Flanged): Flanged, with external hinge

RISER

Riser Type(Wet/Dry): Wet

Rectifier Type:

Wiring Condition:

Rectifier Location

Enclosure Condition:

Rung Spacing: 12"

Mounting System: Welded at roof with floor bracket

Ladder Width: 16"

Riser Opening Safety System: Yes, steel grating

Cathodic Protection

No. of Anodes: Anode Condition:

Overflow Piping

Size: 8", extends exterior of tank down column 3 to splash pad. Included flap valve

Weir/Overflow Structure: Flared inlet

Condition: Good, some rust bleed at flanged connection/flap valve

MISCELLANEOUS SITE CONDITIONS

Overflow/Drain Piping

Size: 8"

Flap Valve: Yes Discharge to: Pipe extended four feet above grade

Sample Tap: Yes in altitude valve vault

Coating Condition (Location and Millage): Excellent; Coating Thickness 10.8 - 19.8 mils, Avg. 15.0.

Adhesion between all layers is excellent. Areas of spot corrosion were repaired with Aquatapoxy.

Metal Pitting (Location and Depth): One location of pitting. Approx. 1/16" deep. Repaired in place with

Aquatapoxy.

Miscellaneous Comments: No corrosion observed on the interior of the wet riser.

Interior Ladder

Safety System: Safety rail

Silt Stop Drain Assembly

Height: 18" Removable: No

Condition: Good with deflector plate

BOWL, INTERIOR

Inlet/Outlet Piping

Size: 12"

Condition: Good

Bowl General Condition: Excellent condition with less than 5 locations of spot corrosion on interior floor.

Miscellaneous Comments: Communication cables attached to bowl ladder. Two SCADA antennas mounted to handrail (Katherien Scala). One separate 24" bolted access hatch on roof by vent - good condition, no hinges but chain is attached to hatch. Adhesion on bowl roof & at balcony is good on prime

& intermediate coating but top coat is brittle.

Location of Samples Taken: None Taken - information from last rehab project available

Interior -

Exterior -

Site Grading/Drainage: Good; away from tank

Access Road Condition: Gravel/grass, good condition

Miscellaneous Site Comments: Two locations of tree damage. See site plan.

Fencing:

Height: 7' Type: Metal Security Wire: Yes

Condition: Good Gate Type: Double Leaf

COATING SAMPLES

APPENDIX C

Site Plan

SHEET TITLE

SHEET NO.

DATE

PROJECT NO.

SCALE

17037

12/05/17

DESKTOP-992NOGD 4:33:20 PM P:\bham\Douglasville\17037_WestBanksMill_BeulahTank\Drawings\W. Banks Mill\WestBanksMillTank-S1 - 2017 Inspection.dgn12/18/2017

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NO SCALE

DOUGLASVILLE, GEORGIA

WATER AND SEWER AUTHORITY

DOUGLASVILLE - DOUGLAS COUNTY

S1

SITE PLAN

V

V

V

V

LADDER

GATE

OVERFLOW

W E

S T B

A N

K S M

IL

L R

D

12"W

VAULT

VALVE

ALTITUDE

ABOVE GARAGE

TANK DRAIN

TREES

TREES

PAD

SPLASH

ELEVATED STORAGE TANK

WEST BANKS MILL 500,000 GALLON

TREE DAMAGE

#1

#2

#3

#4

#5

#6

APPENDIX D

Aerial Photo of Site

SHEET TITLE

SHEET NO.

DATE

PROJECT NO.

SCALE

17037

12/05/17

BHM-ENGL-17 12:19:04 PM P:\bham\Douglasville\17037_WestBanksMill_BeulahTank\Drawings\W. Banks Mill\WestBanksMillTank-T1 - 2017 Inspection.dgn12/11/2017

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B S E

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DOUGLASVILLE, GEORGIA

WATER AND SEWER AUTHORITY

DOUGLASVILLE - DOUGLAS COUNTY

T1

AERIAL PHOTO

ELEVATED STORAGE TANK

WEST BANKS MILL 500,000 GALLON