Addendum No. 1 (4).pdf

10800 Pecan Park Blvd., Suite 205, Austin, TX 78750 | (815) 459-1260 | baxterwoodman.com

ADDENDUM NO. 1

Travis County WCID Point Venture

Augusta Storage Tank Replacement (New 0.25 MG EST)

8/28/2026

Addendum No. 1 to the Plans, Contract Documents and Specifications for the above listed project:

General

1. Neltronics is an approved SCADA Integrator. Contact Stan Nelke 512-217-6789 or snelke@neltronics.net. Specification 13330 shall be updated accordingly with the Contract

Documents.

2. SCADA integration is included with the scope of work. See Specification 13330 and other

Division 13 Specifications included in the bid documents.

3. Working hours are in the General and Special Conditions. Saturday work is allowed from 9am to

6pm. No Sunday or Holiday work is allowed.

a. No inspections will take place on Saturdays.

4. For wage rates, Contractor’s attention is directed to Section 5.1(b) of the General Conditions.

5. CAD drawings are available after signing an electronic release form. Contact mosgood@baxterwoodman.com or mbevilacqua@baxterwoodman.com to obtain release and

CAD file. CAD files are being provided as a courtesy for informational use only. The sealed

Drawings, Specifications, and Contract Documents remain the official design documents and shall govern should any conflict, discrepancy, or omission be identified in the CAD files.

6. The pavement repair on Summit Ridge Drive and Venture Drive is 2” Type D asphalt overlay repair. This repair and the base bid assumes this portion of asphalt will be damaged during construction and needs to be replaced. The detail on Sheet #18 pertains to the alternate bid for an asphalt access road within the tank site, not Summit Ridge Drive or Venture Drive.

7. The 5” thickness of the concrete access drive in the Geotech report is a minimum. The 6” concrete thickness noted in the detail on Sheet #18 shall be used.

8. The 3x5 rock rip rap adjacent to the overflow concrete pad shall be 8" to 10" thick.

9. The tank diameter of 48-ft shown on the plans shall be considered typical. The diameter can vary based on each individual tank manufacturers standard tank dimensions, however, the overflow must remain at 959.5, the capacity be at least 250,000-gallons, the operating range must remain at 30-ft +/- 3-ft.

10. If mailing a bid, notify Baxter & Woodman via email the date the bid was mailed and any tracking information. Email: mosgood@baxterwoodman.com and mbevilacqua@baxterwoodman.com

Alternate Bid Item A1

1. The existing GST is a 30-ft diameter tank. The distance from base of the tank to the overflow is

56-ft.

2. The existing GST must remain online until the new tank is placed successfully into service. The GST cannot be demoed until after substantial completion is achieved. If this alternate bid item is selected, an additional 45 Calendar Days will be added to the Contract Time between Substantial and Final Completion in order to complete this work.

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SECTION 13204

WELDED STEEL ELEVATED STORAGE TANK – SINGLE PEDESTAL SPHEROID

PART 1: GENERAL

1.01 DESCRIPTION

1. Scope of Work:

A. The work to be performed under these specifications includes furnishing all labor, materials, tools and equipment necessary to design, fabricate, construct, and test a single pedestal spheroidal welded steel elevated water storage tank, including the design and construction of the foundation, concrete floor, steel panels, welds, and accessories as shown on the drawings and specified herein.

The work shall also include all labor, materials and equipment necessary to clean, paint and disinfect the water storage tank as specified herein.

B. Except where otherwise noted, the latest revision of AWWA Standard D100-96 shall be followed for the tank design, construction and inspection; and the latest revision of AWWA Standard D102-

97 shall be followed for the tank painting. Design shall meet requirements set forth by the Texas

Commission on Environmental Quality (TCEQ).

C. All material used on this project shall be new and workmanship shall be of the best quality.

Qualified and skilled workmen shall be employed for all phases of this project.

2. Description:

A. This project consists of a 250,000-gallon elevated water storage tank.

B. The tank and support structure shall be of the single pedestal spheroidal style as designed and constructed by Caldwell Tanks; CB&I, Landmark; Maguire Iron, Inc., Phoenix Fabricators & Erectors;

or pre-approved other. The tank and support structure shall be of all welded steel design.

3. Operating Parameters:

Minimum capacity within operating range: 250,000 gallons

Maximum fill rate: 2,000-gpm

Maximum withdrawal rate: 3,500-gpm

Overflow shall be sized for: 3,500-gpm

Elevation – Overflow: 959.5-ft (above MSEL)

Elevation – Top of Foundation: 827.5-ft (above MSLE)

Nominal Operating Range: 30-ft +/- 3-ft

4. Related Documents:

A. The Construction Drawings and the General Conditions and Special Conditions of these Contract

Documents apply to work in this Section.

1.02 FOUNDATION

1. The storage tank contractor shall design and install the tank foundation. The foundation design shall be sealed by a Registered Professional Engineer licensed to practice in the State of Texas. A copy of the

Geotechnical Engineering Study is attached with the Contract Documents.

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1.03 QUALITY ASSURANCE

1. Qualifications and Experience:

A. All tank work shall be performed by a company which specializes in the design and construction of single pedestal spheroid style welded steel elevated water storage tanks using the methods of fabrication which are capable of meeting all the requirements of these specifications. No company is considered qualified unless it has designed and built in its own name at least five (5) single pedestal spheroid style welded steel elevated water storage tanks, conforming to AWWA D 100, of 250,000 gallon or greater capacity in the last ten years.

B. Contractors not on the list of Prequalified Contractors at the time of advertisement as noted in

Section 1.01 (2) of this specification, wishing to bid, shall submit Section 00440 - Information

Required of Bidder showing the prerequisite experience and return to Engineer for review a minimum of fourteen (14) days prior to Proposals being opened for review. Additional information not specified in Section 00440 that may show the Contractor’s ability to perform this work and/or attest to the quality of their work may also be included. Submittal by a Contractor for consideration is acknowledgement that the decision of the Engineer and Owner as to whether or not they will be Prequalified is final.

2. Singular Responsibility:

A. It is the express intent of this Specification to create a singular responsibility for the design and construction of the single pedestal spheroid style welded steel elevated water storage tank. The design and construction of all aspects of the foundation, floor slab, wall and roof of the single pedestal spheroid style welded steel elevated water storage tank are the responsibility of the tank

Contractor and shall not be otherwise assigned. Subcontractors may be employed for excavation, labor, mechanical and other aspects of the work, but overall responsibility for the storage tank remains with the tank Contractor.

1.04 REFERENCE STANDARDS

1. The latest edition of the following standards and specifications shall be used:

A. American Concrete Institute (ACI)

117 - Standard Tolerances for Concrete Construction and Materials

301 - Structural Concrete for Buildings

302 - Guide for Concrete Floor and Slab Construction

304 - Guide for Measuring, Mixing, Transporting and Placing Concrete

305 - Hot Weather Concreting

306 - Cold Weather Concreting

308 - Standard Practice for Curing Concrete

309 - Recommended Practice for Consolidation of Concrete

315 - Details and Detailing of Concrete Reinforcement

318 - Building Code Requirements for Reinforced Concrete

347 - Guide to Formwork for Concrete

SP-4 - Formwork for Concrete

211.1 - Standard Practice for Selecting Proportions for Normal, Heavyweight, and Mass

Concrete

212.2 - Guide for Use of Admixtures in Concrete

214 - Recommended Practice for Evaluation of Strength Test Results of Concrete

304.2 - Placing Concrete by Pumping Methods

B. American Institute of Steel Construction (AISC)

S335 - Specification for Structural Steel Buildings

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C. American National Standards Institute (ANSI)

B16.5 - Pipe Flanges and Flanged Fittings

D. American Petroleum Institute (API)

650 - Welded Steel Tanks for Oil Storage

E. American Society for Testing Materials (ASTM)

A123 - Zinc Coatings on Iron and Steel Products

A185 - Steel Welded Wire Reinforcement, Plain, for Concrete

A240 - Stainless Steel Plate, Sheet and Strip for Pressure Vessels

A285 - Pressure Vessel Plates, Carbon Steel

A615 - Deformed and Plan Carbon-Steel Bars for Concrete Reinforcement

A774 - Welded Stainless Steel Fittings

A778 - Welded Stainless Steel Tubular Products

C920 - Specification for Elastomeric Joint Sealants

D412 - Test Methods for Rubber Properties in Tension

D624 - Test Method for Rubber Property – Tear Resistance

D638 - Test Method for Tensile Properties of Plastics

D746 - Test Method for Brittleness Temperature of Plastics and Elastomers by Impact

D747 - Test Method for Apparent Bending Modulus of Plastics by Means of a Cantilever

Beam

D1056 - Specification for Flexible Cellular Materials – Sponge or Expanded Rubber

D1752 - Specification for Performed Sponge Rubber and Cork Expansion Joint Fillers for Concrete Paving and Structural Construction.

D 2240 - Test Method for Rubber Property – Durometer Hardness

F. American Water Works Association (AWWA)

D100 - Welded Steel Tanks for Water Storage

D102 - Coating Steel Water Storage Tanks

C652 - Disinfection of Water Storage Facilities

G. Federal Aviation Administration (FAA)

70/7460-1H - Obstruction Marking and Lighting

H. National Association of Corrosion Engineers (NACE)

RP0178

I. National Fire Protection Association (NFPA)

NEC - National Electric Code 780 Standard for the Installation of Lightning Protection

Systems

J. National Sanitation Foundation (NSF)

61 - Standard for Drinking Water System Components

K. Occupational Safety and Health Administration (OSHA)

29 CFR - Part 1926 Safety and Health Regulations for Construction

L. Steel Structures Painting Council (SSPC)

VIS-89 - Visual Standard for Abrasive Blast Cleaned Steel

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M. Texas Commission on Environmental Quality (TCEQ)

290 - Rules and Regulations for Public Water Systems

N. Other

ASME Boiler and Pressure Vessel Code, Section IX

CRD - C572 PVC Waterstop

CRSI – Manual of Practice

CRSI 62 – Recommended practice for Placing Reinforcing Bars

CRSI 65 – Recommended Practice for Placing Bar Supports, Specifications, and

Nomenclature.

1.05 GEOTECHNICAL INVESTIGATION

1. A copy of the Geotechnical Engineering Study performed for this site is attached with the Bid/Contract

Documents. Any further testing or information deemed necessary by the Contractor will be at the

Contractor’s expense.

1.06 SUBMITTALS

1. In addition to the requirements stated in Section 01330, Submittals, the following also apply:

A. A preliminary section view drawing of the proposed tank shall be included as part of the Bid

Documents. The drawing shall include sufficient detail to illustrate tank geometry, primary dimensions, the elevation of low and high water levels and other information required to show compliance with the specification. The design shall by signed and sealed by a Professional

Engineer licensed to practice in the State of Texas. If a Preliminary Section View Drawing is not included with the Bid Documents, or the proposed design does not comply with the specifications, the bid may be rejected at the Owners discretion.

B. The elevated storage tank contractor shall submit detailed construction drawings of the elevated tank and foundation for approval by the Engineer prior to fabrication. Reinforced concrete details shall include construction joints, openings and inserts. Reinforcement shall be clearly indicated on the structural drawings and identified by mark numbers that are used on the fabrication schedule. Location, spacing and splice dimensions shall be shown. Placement and fabrication details shall conform to ACI 318. Steel tank details shall include weld joints and a layout showing all primary and secondary shop and field welds. The drawings shall be signed and sealed by a Professional Engineer licensed to practice in the State of Texas. The Contractor shall supply a PDF copy of the design for review. A PDF copy with review comments will be returned to the Contractor.

C. The elevated storage tank contractor shall submit a summary of the design for the foundation, support structure and the tank prior to fabrication. This shall include the design basis, loading and results showing conformance with the specifications and the reference codes and standards.

The design shall by signed and sealed by a Professional Engineer licensed to practice in the State of Texas. The Contractor shall supply a PDF copy of the design for review. A PDF copy with review comments will be returned to the Contractor.

D. Welder’s certifications shall be submitted in accordance with AWWA D100.

E. Upon completion of construction, the elevated storage tank contractor shall provide a minimum of four (4) copies of an Operating and Maintenance Manual containing operating instructions, 13204 - Welded Steel Elevated Storage Tank-Single Pedestal Spheroid Page 5 of 12 maintenance instructions, as-built construction drawings, a gage table, and catalog cut sheets of the equipment installed.

1.07 SEQUENCING AND SCHEDULING

1. Schedule: The Contractor shall provide a bar chart showing the anticipated schedule for design, submittals, site work and the major components of construction including foundation, support structure and tank. In addition, show tank painting, electrical installation and other significant activities. Update the schedule as required.

2. Notification: The Contractor shall provide notification of the intent to start work at least seven days prior to commencing each major phase of work.

1.08 CERTIFICATIONS

1. Prior to construction, provide certification from the engineer of record that the elevated tank has been designed in accordance with the requirements of the specification. Upon completion of construction the Contractor shall provide certification from the Professional Engineer of record that the elevated tank has been constructed according to the submitted and approved Construction Drawings and Design.

PART 2: PRODUCTS

2.01 GENERAL

1. Furnish an elevated water storage tank as shown on the drawings and as specified in this section. The design, materials, fabrication, construction, testing and inspection of the tank, support structure and foundation shall comply with the latest edition of AWWA D100, except as modified herein. Tank capacity, head range, height to TCL and top of foundation elevation shall be as shown on the drawings and as listed in Part 1.01 Description, No. 3 Operating Parameters, of this Section.

2.02 DESIGN CRITERIA

1. Dead load shall be the weight of all permanent construction and fittings.

2. Water load shall be the weight of all of the liquid when the tank is filled to the overflow.

3. Snow load shall be 25 pounds per square foot, in accordance with current AWWA D100 Standards.

4. Wind load shall be 100 miles per hour from any direction, in accordance with current AWWA D100

Standards.

5. The tank shall be designed for Zone 0 Earthquake resistance by the fixed percentage method in accordance with current AWWA D100 Standards.

6. The design for all sections of the steel tank shall be per the classes of materials and unit tension/compression stresses mentioned in the latest edition of AWWA D100.

7. All openings in the support structure shall be properly reinforced. Loads imposed by openings in the base of the support structure shall be accommodated in the foundation design.

8. The overturning moment used in designing the support structure and foundation shall include the moment due to eccentricity of the gravity loads caused by deflection of the structure under wind or seismic conditions (i.e. P-Delta effect).

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9. Unless otherwise noted, at junctions in plates where meridional forces are discontinuous such as cone to cylinder junctions, a tension or compression ring may be required to resist the radial forces generated. In these regions, the allowable stresses shall not exceed those referred to in AWWA D100.

A. Tension ring stresses shall not exceed the lesser of 15,000 psi or one half of the minimum specified yield of the plate material.

B. Compression ring stresses shall not exceed 15,000 psi.

C. To determine the stresses in the ring due to discontinuity forces, the tank plates immediately adjacent to the discontinuity may be assumed to participate for a distance of Rt78.0 .

10. There shall be a one sixteenth (1/16) inch minimum corrosion allowance for wetted areas only.

11. The concrete foundation(s) shall be designed by the Contractor using the recommendations given in the geotechnical report. As a minimum, the foundation shall be in accordance with American Concrete

Institute (ACI) and American Water Works Association (AWWA) standards and shall safely support the structure.

12. Earth cover shall be a minimum of three (3) feet over top of pipe. Any pipe passing through the foundation which does not meet this minimum cover requirement, shall be properly insulated until such minimum cover is achieved.

2.03 TANK

1. The elevated tank shall be all welded construction and shall be designed in accordance with the applicable sections of the latest revision of AWWA D100 unless otherwise noted. The required capacity and dimensions are noted on the Drawings and in this Section of the specifications. All members shall be designed to safely withstand the maximum stress to which they may be subjected during erection and operation. The minimum thickness of any steel plate shall be 1/4-inch.

2.04 APPURTENANCES

1. General:

A. Appurtenances shall comply with the minimum requirements of the Specifications, Codes and

Standards listed in Part 1.04, Reference Standards, of this Section and operating requirements of the structure.

a. Appurtenances shown on the plans shall also be included even if not described and/or listed in this Specification.

2. Tank Entry:

A. One 36 inch, minimum, by 80 inch, minimum, plate access door, with vent, with flush threshold shall be provided and located in the base of the support structure complete with a handle and drip cover. The door shall be fabricated from steel plate with adequate stiffening and specifically designed for use with the tank. A step-over threshold is not acceptable. A ‘Locknetics’ programmable lock shall be installed on the door.

3. Piping & Pressure Relief:

A. An outlet pipe shall be provided from the bottom of the tank to a flanged connection at the base of the support structure. Outlet pipe shall be sized as noted on the plans. The bottom capacity level of the tank’s operating range shall be at or above the elevation of the top of the outlet pipe.

The outlet pipe shall be welded steel and have a thickness not less than standard weight pipe.

The outlet pipe shall have an expansion joint above the base bend. Piping below the grade slab shall be flanged cement lined ductile iron suitably restrained to resist movement.

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B. A inlet pipe shall be provided that extends up the inside of the nominal operating range of the bowl. The inlet pipe size and termination elevation shall be as noted on the plans. The inlet pipe shall be welded steel and have a thickness not less than standard weight pipe. The inlet pipe shall have an expansion joint above the base bend. Piping below the grade slab shall be flanged cement lined ductile iron suitably restrained to resist movement.

C. An overflow pipe equipped with an anti-vortex entrance detail shall be provided. The overflow pipe shall be sized to meet the overflow rate stated in Part 1.01 Description, No. 3 - Operating

Conditions, of this Section. The overflow pipe shall be welded steel and have a thickness not less than 1/4 inch. The overflow shall extend down the inside of the access tube and support structure and discharge at a point approximately one (1) foot above grade. The end of the overflow shall discharge through a weighted flap valve onto a concrete splash pad, as detailed in the

Construction Plans. Flap valve shall fit tightly with no gap over 1/16th of an inch.

D. A minimum of one pressure-vacuum vent near the center of the roof shall be provided. The vent(s) shall be sized to handle pressure differential caused by water entering or leaving the tank at a maximum rate. The inlet and withdrawal rates shall be as stated in Part 1.01 Description, No.

3 - Operating Conditions, of this Section. The open area of the overflow shall not be considered as a venting area. The vent(s) shall have insect screens and shall be designed to relieve any pressure or vacuum in the event the screen frosts over or is otherwise clogged and shall be easily dismantled for cleaning. Screens shall be 16-mesh or finer and clamped into place with stainless or galvanized bands or wires and designed to withstand the winds of not less than the design criteria provided in this specification. The vent(s) shall be self-correcting. The pressure-vacuum vent may be mounted in the exhaust hatch cover plate.

E. Tank Drain Assembly: A tank drain assembly shall be provided, which shall include a minimum 4

in. pipe and 4 in. ball valve. The drain pipe entrance shall be on the tank floor, as low as possible, and be connected to the overflow pipe. The tank drain pipe shall be constructed of welded steel, with galvanized brackets, guides and hangers. The ball valve shall be installed in a location which is easily accessible from the walkway platform without the use of a ladder or other device.

F. Level Indication: A level transmitter and sampling tap shall be installed as shown on the

Construction Plans.

4. Access, Ladders, & Platforms:

A. Provide a ladder system, which extends from grade to the upper shaft platform. Ladders located in the support structure and access tube interior shall be galvanized steel. Tank interior ladders shall be coated in accordance with the tank interior coating system. All ladders shall have a minimum of 16” (minimum) clearance between rails. The ladder and ladder safety devices shall meet all OSHA standards.

B. Provide a ladder on the interior of the access tube from the upper shaft platform to the tank roof.

This ladder shall be equipped with ladder safety rail or cable, and a removable extension. The ladder and ladder safety devices shall meet all OSHA standards.

C. The ladder safety rail or cable shall be an OSHA approved galvanized system as manufactured by

CB&I Industries, or equal. Provide a removable extension for each ladder. The owner shall be supplied with two (2) harnesses and two (2) sleeves.

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D. Rest platforms shall be provided at maximum 40 foot intervals along the interior pedestal ladder.

The platform shall be in accordance with OSHA requirements. Platform shall be arranged for straight run ladder and operable without removing fall prevention equipment.

E. A steel condensate ceiling with drain shall be supplied, located at the junction of the pedestal shaft and base bell. The condensate ceiling shall be equipped with a steel drain pipe connected to the overflow pipe.

F. An upper shaft platform shall be supplied, located at the top of the support structure.

G. Provide an access tube located on the vertical centerline of the tank. The access tube shall have a minimum diameter of 48 inches and shall provide access from the upper shaft platform to the tank roof. The access tube shall be coated in accordance with the tank interior coating system.

H. A 42-inch tall handrail shall be installed on tank roof around the perimeter of the hatches, as shown and detailed on the Plans. Handrails shall be welded carbon steel angle and shall be coated per exterior metal.

5. Manholes, Hatches, & Vents:

A. At the top of the support structure, a painters access manhole shall be provided giving access to the painters rings. Manhole shall be sized as noted on the plans.

B. One 30-inch and one 36-inch diameter hinged rain proof hatches shall be supplied. One shall be at the top of the access tube with chain, hook and inside handle. The other shall be adjacent to the access tube for entry into the tank and shall have a handle and hasp. The hatch openings shall have a curb four inches high and the cover shall have a downward overlap of two inches.

C. One 30-inch diameter flanged exhaust hatch shall be supplied, located adjacent to the access tube and so constructed that an exhaust fan may be connected for ventilation during painting.

D. Access hatches shall be provided in both the condensate ceiling and the upper platform. The access hatches shall have a minimum opening of 30”x30” with opening to allow ladder and safety device to continue 48” minimum above the platform floor.

E. All access openings shall have a raised curbing at least four (4) inches in height with lockable gasketed cover that overlaps the curbing at least two (2) inches

6. Painter’s Rails:

A. Provide painters rails as shown on the drawings and specified herein:

I. Interior Painters Rails. A rail shall be attached to the underside of the roof at the roof-to-shell junction.

II. Exterior Painters Rails. Two rails shall be located near the top of the support pedestal and be accessible from the upper shaft platform via the painters access manhole.

7. Antenna Mounts:

A. Provide antenna mounts as shown on the drawings and specified herein

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2.05 ELECTRICAL

1. Interior and exterior waterproof light fixtures with rigid conduit, wiring and switches as well as electrical outlets and other electrical appurtenances shall be provided as detailed on the Plans and in the

Electrical Specifications, attached to these Contract Documents.

2. Obstruction lighting shall be provided on the roof of the tank near the apex. The lights shall be enclosed in aviation red obstruction light globes as approved by the FAA, complete with an automatic photo-electric cell type switch. The photo-electric cell shall be located at the base of the tank. The contractor shall install all conduit and wiring from the light to the electrical service panel.

3. Provide two 2 in. spare conduits and four 1 in. spare conduits, stubbed out through the tank floor and extending 5 feet past the foundation, for future use. Cap the ends.

4. Provide Cathodic Protection per the electrical and instrumentation control plans and specifications.

PART 3: EXECUTION

3.01 GENERAL

1. The project site shall be kept in a clean and safe condition at all times. The Contractor shall remove all construction equipment and debris at project completion.

3.02 FIELD QUALITY CONTROL

1. Inspection and testing shall be in accordance with AWWA D100, Section 11.

2. Radiographic inspection of full penetration butt welded joints shall be made by an independent inspection company provided by contractor.

3. Owner will retain the services of an independent AWS Certified Welding inspector and NACE Certified

Coating Inspector for quality control of welding techniques, preparation of steel, and coatings application.

4. Contractor is responsible for providing access to tank, communicating work progress, and coordinating inspection services with Owner’s independent consultant.

5. Concrete testing shall be as follows:

A. Concrete testing shall be as called for in Section 01450 – Quality Control.

6. Inspection of Painting Operations:

A. Testing and inspection of surface preparation and painting operations shall performed by the

Owner and/or Owners Representative as called for in Section 09916 of the Technical

Specifications.

3.03 CONCRETE FOUNDATION

1. The foundation bearing surface and excavation shall be inspected by a representative of the geotechnical engineer prior to foundation construction. Verification of the applicable design and construction recommendations is required. The geotechnical engineer shall be retained by the Owner.

2. The inlet pipe, outlet pipe and electrical conduit extending outside the foundation wall shall be included as part of the foundation.

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3. The interior of the support structure base shall be finished with a concrete floor. All excavated areas under the concrete floor shall be backfilled with suitable material and compacted as specified by the design engineer.

4. All concrete work, including concrete, formwork and reinforcing, shall comply with the applicable sections of the latest revisions of the ACI Standards.

3.04 STEEL TANK CONSTRUCTION

1. All welding shall comply with AWWA D100.

2. All welding procedures, welders and welding operators shall be qualified in accordance with ASME

Section IX for the processes and positions utilized.

3. The edges or surfaces of the pieces to be joined by welding shall be prepared by flame cutting, plasma arc cutting, arc gouging, machining, shearing, grinding or chipping and shall be cleaned of detrimental oil, grease, scale and rust. The edges of the pieces may have a protective coating applied to them, which need not be removed before they are welded unless specifically prohibited by the welding procedures.

4. All welded connections not specifically designed to be full or partial penetration welds shall be seal welded including but not limited to underside roof plate laps, roof support system, ladder clips and etc.

5. Welding procedures and general welding requirements shall be in accordance with AWWA D100, Section 8, “Welding”. Welding shall only be done by ASME qualified welders. No structural welding is permitted to any steel embedded in hardened concrete, unless the weld is at least 2 ft. from the embedment interface. Grinding of weld contour shall approximate condition of NACE Standard

RPO178 designation “C”.

6. Plates and component members of the tank shall be assembled and welded following erection methods, which result in a minimum of distortion from weld shrinkage. Surfaces to be welded shall be free from loose scale, slag, heavy rust, grease, paint and other foreign material.

PART 4: COATINGS & FINISHES

1. All tank painting and paint testing shall be in accordance with AWWA D102, the Steel Structures

Painting Council Specification SSPC-PA1, the approved paint manufacturer specifications and as specified herein.

2. Each paint system shall be from a single manufacturer. The coatings and finishes for the elevated tank shall meet the requirements as stated in Sections 09916 of these Technical Specifications.

PART 5: TESTING AND STERILIZATION

1. Sufficient cure, per the manufacturer's recommendations, of the final coat on the interior wet surface shall be allowed before the elevated tank is sterilized and filled with water.

A. Prior to starting disinfection, provide adequate ventilation to “air” the tank in accordance with this specification, Specification 09916, and in accordance with manufacturer’s recommendations. During the paint curing period, the roof manway is to be left open. Once the disinfection process is begun, the roof manway shall remain closed.

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2. The tank shall be sterilized per the latest revision/requirements of AWWA C652. Acceptable forms of chlorine for disinfection shall be:

A. Liquid chlorine (4.2.1) or Sodium Hypochlorite (4.2.2) as specified in AWWA C652

i. Acceptable methods of chlorination per AWWA C652:

1. Section 4.3.2 (Chlorine Method 2)

2. Section 4.3.3 (Chlorine Method 3)

3. Section 4.3.1 (Chlorine Method 1) is not acceptable unless the Contractor pays for all water used in the testing and sterilization.

B. Calcium hypochlorite (HTH) is not acceptable.

C. Dechlorination of the disinfecting water shall be in strict accordance with current AWWA

Standard C655-18.

3. The Owner, free of charge to the Contractor, shall furnish sufficient water for testing and sterilization of the new storage tank and associated piping at a rate which will allow the Owner to adequately furnish water service to its existing customers if Chlorine Methods 2 or 3 are used. The water shall be at proper pressure to fill the tank to the maximum working level. Any leaks in the tank that are disclosed by this test shall be repaired by chipping, gouging, or oxygen gouging to remove any defective welds and re-welded. The method of repair shall be approved by the Owner’s

Representative prior to repair by the Contractor. No repair work shall be done on any joint unless the water in the tank is at least 2 feet below the joint being repaired. Any paint damaged by repairs shall be properly restored. Once repaired, the tank shall be retested for leaks and the additional water paid for by the Contractor.

A. Upon completion, the tank shall be tested to determine watertightness. The tank shall be filled halfway to the maximum level. The test shall consist of measuring the liquid level over the next

24 hours to determine if any change has occurred. If a change is observed and exceeds the maximum allowance, the test shall be extended to a total of five days. If at the end of five days the average daily change has not exceeded the maximum allowance, the test shall be considered satisfactory. The tank shall then be filled to the maximum level and the procedure repeated.

B. The liquid volume loss for a period of 24 hours shall not exceed one-twentieth of one percent of the tank capacity, 0.0005 x tank volume. If the liquid volume loss exceeds this amount, it shall be considered excessive, and the tank shall be repaired and retested at the Contractor’s expense.

C. Damp spots will not be permitted at any location on the tank. Damp spots are defined as spots where moisture can be picked up on a dry hand. All such areas shall be repaired as necessary.

D. The cost of water required for re-testing and/or re-sterilization due to failure of the initial test by the Contactor will be the financial responsibility of the Contractor.

E. If Chlorine Method 1 is used, the cost of all water, for both the initial testing and any subsequent retesting, will be the financial responsibility of the Contractor.

4. Upon completion of the sterilization procedure, the Owner or his representative, shall arrange and bear the initial cost of any bacteriological testing of water samples from the tank that may be required. If the test results do not pass, the Contractor will pay for subsequent sterilization and testing. The tank shall not be placed in service until safe test results are obtained.

A. Verify that the residual chlorine in the tank is 2.0 mg/L or less before placing the tank in service.

13204 - Welded Steel Elevated Storage Tank-Single Pedestal Spheroid Page 12 of 12

PART 6: GUARANTEE

1. The Contractor shall guarantee the structure, appurtenant equipment and accessories provided under this Section for a minimum period of one year from the date of substantial completion.

Substantial completion is defined as the date when the tank is placed, or available to be placed, into service. The Contractor will repair any defects of which they are notified during that period which may appear because of faulty design, workmanship or materials furnished under the specifications.

Defects caused by damaging service conditions such as electrolytic, chemical, abrasive or other damaging service conditions are not covered by this guarantee.

2. All guarantees obtained by the Contractor from the manufacturer or installer of paint, equipment or accessories not manufactured by the Contractor shall be obtained for the benefit of the Owner.

END OF SECTION