PUBLIC WATER WELL SPECIFICATIONS

8/9/2019 PUBLIC WATER WELL SPECIFICATIONS

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TAC32-11.D10 02520-1

SECTION 02520

PUBLIC WATER WELL SPECIFICATIONS

1.01 SCOPE OF WORK:

The scope of work for this project includes mobilization and demobilization, the

furnishing of all labor, tools, equipment, and material, performing all operations in

connection with installing a water well, water lines (well and pumps), underground

storage tanks, booster pump, controls, well pump, and all system electrical wiring.

Location is shown on attached drawings.

1.02 SECTION INCLUDES

A. Drilling, collection of water samples, casing, screening, gravel pack, developing, test

pumping, and disinfecting of water supply well.

1.03 SPECIAL REQUIREMENTS

A. The well is to be drilled to the depth necessary to produce the required flow and water

quality to comply with NM State potable water quality standards.

B. All materials to remain in the finished well shall be new and free of defects.

C. Well drilling, development, testing, and cleaning equipment shall be furnished by the

Contractor at no additional cost to the Owner.

D. Formation samples necessary for sizing the well appurtenances will be submitted by

the Contractor at no additional cost to the Owner.

E. Special materials and products to be used in well drilling and developing will be

subject to Engineers approval prior to their use.

F. Mobilization and Demobilization:

1. The Contractor shall begin drilling operations within one month from the date

of receipt of Notice to Proceed. The Contractor shall bring to the site, erect, and

install all equipment and supplies necessary for the completion of the project.

Compensation for mobilization and demobilization shall be included as part of

the lump sum bid price.

G. Well Location:

1. The location of the site on which the well will be drilled is shown on the

Contract drawings.


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TAC32-11.D10 02520-2

1.04 EQUIPMENT AND MATERIALS:

A. Well Pump:

1. The well shall be equipped with a submersible pump capable of delivering 25

gpm at 800 ft. depth. The pump shall be set on NSF approved 1 Schedule 80

PVC pipe ASTM D1785.

B. Booster Pump/Pressure Tanks:

1. The water system shall be equipped with a booster pump/pressure tank station

and shall be Grundfos # ME2 CRE4-50 or approved equal.

C. Chlorinator:

1. A chlorinator shall be installed and located per owners approval. Chlorinator

must be sized to match flow of BS-1.

D. Pump House:

1. The pump station shall be installed in an underground 8 ft. deep corrugatedmetal pit or approved equal. Provide manhole and ladder for access and/or

steel hatch cover with the ability to lock and secure. See construction plans.

E. Water Meter:

1. The well shall be equipped with a 1 totalizing water meter, located in the

pump house.

F. Underground Water Storage Tanks:

1. The well system shall be equipped with one 1700-gallon polyethylene below

ground water storage tanks, Harrington Ind. Plastics or approved equal. The

tanks shall be plumbed to function as one tank and equipped with an adjustablefloat switch/level controllers to control the well pump. See construction plans.

G. Water Lines:

1. The waterline from the well to the storage tank and from the storage tank to the

booster pump shall be 2 diameter NSF approved Schedule 40 PVC pipe

ASTM D1785. It shall be buried with a minimum cover of three (3) feet, or as

shown on the construction plans.

H. Electrical Connections:

1. The contractor shall furnish all electrical equipment internal to the operation of

the well, pumps, and tanks. Power will be provided as part of the infrastructure

improvements at the site. The contractor will be responsible for coordination of

any electrical requirements/needs with the owner.


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TAC32-11.D10 02520-3

1.05 MATERIALS AND CONSTRUCTION

A. Well Casing:

1. The well casing shall be 4 o.d. Schedule 40 NAF approved PVC pipe. It

shall meet ASTM F-480 requirements. The casing shall have solvent weldedwatertight joints.

B. Well Screen:

1. It is expected the well will produce fine sands, thus well screens are deemed

necessary by the Engineer. The well shall be equipped with a 4 o. d. factory

slotted PVC screen. The screen shall be Schedule 40 NSF approved PVC pipe

and shall meet ASTM D1785 requirements. The well screen shall be installed

in accordance with Chapter 12 of Groundwater and Wells - 1966 by Edward

E. Johnson, Inc. The size of the screen openings shall be 0.020 slots.

C. Gravel Pack:1. A gravel pack shall be placed in the annular space between the drilled hole and

the screen or blank casing and shall be filled from total depth to 5ft. above the

well screen. The gravel must be placed so as to fill the complete annular space

and not allow any bridging or void spaces to form. Gravel pack shall be placed

by the pump and tremie method. The gravel shall be made of well-rounded

hard material size #10-#20.

2. The gravel must be washed free of clays and other fine materials and produced

as near the above gradation as local suppliers can provide. No crushed rock or

gravel with angular faces may be used.

3. The Contractor shall be responsible for insuring that the gravel pack material is

adequately disinfected during installation.

D. Well Fill:

1. The annular space between the hole and the screen shall be filled from 5 ft.

above the well screen to 35 ft. below ground level with a sand bentonite

mixture.

E. Cement Seal:

1. The annular space outside the well casing from 5 ft below ground level to 35 ft.

below ground level shall be filled with 2% bentonite cement.

PART 2 EXECUTION

2.01 WELL DRILLING AND DEVELOPING

A. Well Production Hole:

1. The well production hole shall be drilled using a mud-rotary rig. The upper

portion of the hole shall be 7 7/8 nominal diameter. The lower portion of the


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TAC32-11.D10 02520-4

hole shall be 6 nominal diameter. See plans for complete details.

B. Well Plumbness and Alignment:

1. The completed well shall be sufficiently plumb, round, and straight to allow a

3 7/8 diameter x 20 long mandrel to pass to the total depth of the well.

C. Well/Well Development:

1. The well shall produce a minimum 25 gpm of water. The developing of this

well will be done the air lifting pumping method with the well drillers

equipment supplying the required air.

2. The well shall be thoroughly developed so that it will produce a 25 gpm

minimum capacity and so that it will not produce fine sand.

3. The compressor equipment used for airlifting shall be capable of producing

adequate airflow to lift water and sediment from the lower screens in the well.

Airlifting shall proceed until the produced water is free of suspended sediment.

4. The Contractor shall furnish all plant, materials, and labor required to

accomplish the well development.

D. Damage done to existing structures, roads or utilities, or any interference with them

caused by the Contractor shall be repaired at the Contractor's expense.

2.02 WELL CLEANING AND DISINFECTION

A. All materials, tools and debris shall be removed form the well once it is completed.

B. Sample and test the water at the wellhead as per Section 2.04 of this Section prior to

proceeding with chlorination of the well.

C. Sterilization of the production well shall comply with all standards identified in the

New Mexico Environment Protection Wastewater and Water Supply Facilities

NMAC 20.7.10 and American Water Works Association (AWWA) Standards for

Disinfection of Drinking Water.

Chlorination Procedure:

1. Minimum concentration: 250 mg/l throughout the volume of water present in

the well.

2. Twenty-four hours after application of chlorine, the well shall be pumped to

waste until the chlorine residual is approximately 100 ppm.

D. Sample and test the water at the wellhead as per 2.04 of this Section after chlorination

of the well.


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TAC32-11.D10 02520-5

2.03 METAL CAP FOR CASING

A. The production casing shall extend a minimum of 18 inches above ground level. The

casing shall be equipped with a 4 x 1 Baker-Snappy model 8PL41.24 pitless

adapter with a Baker-Monitor watertight cap with a screened well vent model

4WPSM, or approved equal. A 6 x 6x 6 concrete slab shall be placed around thecasing at the ground level.

B. Other appurtenances required for completion of the well such as the gravel chutes,

breather pipe, and bottom plug are to be furnished and installed by the Contractor.

2.04 LABORATORY ANALYSIS OF WATER

A. Potability tests shall be run to demonstrate that the production well complies with all

standards identified in the New Mexico Environment Protection Wastewater and

Water Supply Facilities NMAC 20.7.10 and American Water Works Association(AWWA) Standards for Disinfection of Drinking Water. Water from the well shall

flow only to waste until full compliance with these sampling, testing, and analysis

requirements have been achieved.

B. Samples shall be taken and analyzed as follows:

1. A sample shall be taken at the wellhead prior to the well being sterilized as per

2.02 of this Section and analyzed for E-Coli, Total Coliform, and Nitrate by the

authority having jurisdiction..

2. A sample shall be taken at the wellhead after being sterilized as per 2.02 of this

Section and analyzed for E-Coli, Total Coliform, and Nitrate. Should the water

quality not pass either of the bacterial tests, the well shall be re-sterilized as per2.02 of this Section and then be re-tested.

C. After the water at the wellhead is found to be compliant with the testing in A and B

above, proceed with sterilization and testing of the distribution piping to the building

and the hot and cold water piping within the building as per Section 15200, 3.16.

END OF SECTION

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PUBLIC WATER WELL SPECIFICATIONS

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