LINC Spec 33 1113 Potable Supply Wells ASI 01.pdf

POTABLE SUPPLY WELLS 33 11 13-1

Long Island National Cemetery ASI 01

Facility Renovation July 3, 2023

815CM3041 ISSUED FOR CONSTRUCTION

SECTION 33 11 13

POTABLE SUPPLY WELLS

TABLE OF CONTENTS

PART 1 - GENERAL

1.1 GENERAL DESCRIPTION

1.2 WORK INCLUDED

1.3 UNIT PRICES

1.3.1 NON-POTABLE IRRIGATION WATER WELL

1.3.2 GEOPHYSICAL LOGGING

1.3.3 AQUIFER TESTING

1.3.4 WATER QUALITY SAMPLING

1.3.5 WELL DECOMMISSIONING OR ABANDONMENT

1.3.6 CLEANUP

1.4 REFERENCES

1.5 ADMINISTRATIVE REQUIREMENTS

1.5.1 NOTIFICATION

1.5.2 DELIVERY, STORAGE, AND HANDLING

1.5.3 PROJECT AND SITE CONDITIONS

1.5.4 WATER WELL DESIGN REQUIREMENTS

1.5.4.1 WELL INSTALLATION PLAN

1.5.4.2 FORMATION SAMPLING

1.5.4.3 GEOPHYSICAL LOGGING

1.5.4.4 WATER SAMPLING AND ANALYSES

1.5.5 QUALIFICATIONS

1.6 SUBMITTALS

PART 2 – PRODUCTS AND MATERIALS

2.1 MATERIAL REQUIREMENTS

2.2 WELL CASING

2.3 WELL SCREEN

2.4 FILTER PACK

PART 3 - EXECUTION

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3.1 PREPARATION

3.2 DRILLING, CONSTRUCTION AND TESTING

3.2.1 WELL DRILLING AND CONSTRUCTION

3.2.2 GENERAL

3.2.3 PILOT HOLE DRILLING

3.2.4 GEOPHYSICAL BOREHOLE LOGGING

3.2.5 SIEVE ANALYSIS OF PRODUCTION ZONE FORMATION SAMPLES

3.2.6 BOREHOLE DRILLING/REAMING

3.2.7 BOREHOLE PLUMBNESS AND ALIGNMENT

3.2.8 DRILLING FLUIDS

3.2.9 WELL CASING AND SCREEN INSTALLATION

3.2.10 FILTER PACK PLACEMENT

3.2.11 GROUTING AND SEALING

3.2.12 WELL DEVELOPMENT

3.2.13 DOWNHOLE CAMERA SURVEY

3.2.14 WELL DISINFECTION

3.3 AQUIFER PUMPING TESTS

3.3.1 TEST PUMP

3.3.2 DISPOSAL OF WATER PUMPED FROM THE WELL

3.3.3 AQUIFER PUMPING TESTS AND REPORTING

3.4 WATER QUALITY SAMPLING

3.5 REQUIREMENTS AFTER AQUIFER TESTING AND SAMPLING

3.5.1 SITE CLEANUP

3.5.2 DRILLING WASTE DISPOSAL

3.5.3 SURVEYS

3.6 FIELD QUALITY CONTROL

3.6.1 WELL DECOMMISSIONING OR ABANDONMENT

3.6.2 DOCUMENTATION AND QUALITY CONTROL REPORTS

3.6.2.1 BOREHOLE LOGS

3.6.2.2 INSTALLATION DIAGRAM

3.6.2.3 WELL COMPLETION REPORT

3.6.2.4 WELL DEVELOPMENT RECORDS

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3.6.2.5 GEOPHYSICAL LOGS

3.6.2.6 HYDROGEOLOGIC REPORT

3.6.2.7 WELL DECOMMISSIONING OR ABANDONMENT RECORDS

3.6.2.8 TESTS

3.6.2.9 PROJECT PHOTOGRAPHS

3.6.2.10 SURVEY MAPS AND NOTES

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PART 1 - GENERAL

1.1 GENERAL DESCRIPTION

Contractor shall be responsible for installing and testing an irrigation well capable of producing and maintaining a minimum sustainable design flow rate of up to 2,000 gallons per minute (GPM) for 24 straight hours per day. Please refer to the ECS Mid-Atlantic, LLC reports titled Irrigation Supply Well

Desktop Evaluation, dated January 21, 2022, and Irrigation Supply Well Depth Evaluation, dated March

29, 2023, for more information about the well and other pertinent information. Please note that these specifications, dated July 3, 2023, supersede the former version, dated January 31, 2022.

While minimum standards are specified herein, the contractor shall be responsible for altered or additional means and methods necessary to provide an irrigation well meeting the required performance characteristics. The Government and Site Engineer shall be consulted prior to deviating from the specifications provided herein.

The Contractor shall be responsible for performing all the work in accordance with these specifications. If evidence indicates that the casing in the well is broken or that the well is not constructed in accordance with the specifications to the satisfaction of the Government, the

Government may order that proper changes be made by the Contractor, or in the event that proper changes cannot be made, the Government may order the Contractor to abandon such well without cost to the Government and to drill a new well.

Unless otherwise specified, the Government shall be responsible for obtaining all drilling-related permits through the New York Department of Environmental Conservation (DEC). The Contractor shall be responsible for abiding by permit requirements and meeting applicable governmental requirements that are in existence on the date of the bid opening and that are designated as the responsibility of the Contractor, unless otherwise provided by the Government.

Certifications and reports shall be submitted as required in other sections of this preliminary design specification as required by the Government.

All reasonably necessary precautions shall be taken during construction of the well to ensure that contaminants do not reach the subsurface environment.

1.2 WORK INCLUDED

A. Install a non-potable irrigation well for cemetery irrigation use

B. Drill a pilot hole and conduct geophysical logging of the pilot hole

C. Casing, screening, and well construction

D. Well development

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E. Down-well camera survey

E. Pumping tests

F. Well disinfection

G. Groundwater sampling

1.3 UNIT PRICES

Payment for each specified item will be made at the contract unit price for that item. Payment includes full compensation for equipment, materials and labor for drilling; removal and disposal of temporary casing, cuttings, and drill fluid; preparation of borehole logs; and sample handling, containers, storage, and testing. Measure depth, logging, installation, casing, riser pipe, and well screen by linear distance. Payment is not allowed for test wells or wells abandoned due to construction practices not in accordance with this specification, faulty construction practices or for the convenience of the Contractor.

1.3.1 NON-POTABLE IRRIGATION WATER WELL

Compensation for the non-potable irrigation water well will be made at the contract unit price and includes material, equipment, and labor required to drill, develop, perform tests, and complete the permanent well. Measure depth as the total linear distance between ground surface and bottom of hole. If the total depth of well is greater than that specified in the contract for “Non-Potable Irrigation Water Well”, the additional depth will be paid for at the contract unit price for “Additional Non-Potable Irrigation Water Well Depth”.

1.3.2 GEOPHYSICAL LOGGING

The “Geophysical Logging” unit price will include interpretation of the logs and their delivery to the Government.

1.3.3 AQUIFER TESTING

Compensation for aquifer testing will be made at the contract unit price and includes material, equipment, and labor required to complete testing as specified herein. If additional testing is needed beyond the that specified herein, the additional testing will be paid for at the contract unit price for “Aquifer Testing”.

1.3.4 WATER QUALITY SAMPLING

The “Water Quality Sampling” unit price will include the analysis of specified analytes and the delivery of laboratory results to the Government.

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1.3.5 WELL DECOMMISSIONING OR ABANDONMENT

Permanent decommissioning or abandonment of wells will be paid for only if it becomes necessary to abandon a well or test well as specified, and only for work completed and accepted as specified. Payment includes compensation for drilling, casing removal, well sampling, materials, cement, mixing of cement, bentonite, and water, pumping of grout, equipment, removal of foreign objects, and transportation necessary to abandon the well and for the required well abandonment records.

1.3.6 CLEANUP

Separate payment will not be made for cleanup of the site. Cleanup means restoring the site to its pre-construction condition, in accordance with paragraph SITE CLEANUP. Cleanup is considered part of and incidental to the drilling, construction, or decommissioning of the well.

1.4 REFERENCES

The publications listed below form a part of this specification to the extent referenced. The publications are referred to within the text by the basic designation only.

A. American Water Works Association (AWWA) / American National Standards Institute (ANSI)

1. AWWA A100 (2020) Water wells

2. AWWA/ANSI B100 (2016) Granular filtration material

3. AWWA/ANSI C200 (2017) Steel water pipe – 6 inch and larger

4. AWWA/ANSI C206 (2017) Field welding of steel water pipe

5. AWWA/ANSI C654 (2013) Disinfection of wells

B. American Petroleum Institute (API

1. API RP 13B-2 (2014) Recommended practices for field testing of oil-based drilling fluids

2. API SPEC 10A (2019) Specification for cements and materials for well cementing

C. ASTM International (ASTM)

1. ASTM A53/A53M (2020) Standard specifications for pipe, steel, Black and hot-dipped, zinc-coated, welded and seamless

2. ASTM A139/A139M (2016) Standard specification for electric fusion

(arc-) welded steel pipe (NPS 4 and over)

3. ASTM A606/A606M (2018) Standard specification for steel, sheet and strip, high-strength, low-alloy, hot-rolled and cold-rolled, with improved atmospheric corrosion resistance

4. ASTM A778 (2021) Standard specification for welded, unannealed austenitic stainless steel tubular products

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5. ASTM C33/C33M (2013) Standard specification for concrete aggregates

6. ASTM C136/C136M (2019) Standard test method for sieve analysis of fine and coarse aggregates

7. ASTM C150/C150M (2004) Standard specification for Portland cement

8. ASTM D75/D75M (2019) Standard practice for sampling

Aggregates

9. ASTM D2488 (2017) Standard practice for description and identification of soils (visual-manual procedures)

D. Code of New York (CNY)

1. CNY ECL §15-1525 (2022) Water well drillers in New York state registration

2. CNY Title 6, Chp. X-A, Art. 3, Part 750 (2022) State pollutant discharge elimination system (SPDES) permits

3. CNY Title 10, Chp. I, Part 5-1, Apx. 5B (2022) Standards for water wells

E. New York Department of Environmental Conservation (DEC)

1. No Document Number (2022) Pumping test procedures for water withdrawal permit applications

F. National Sanitation Foundation International (NSF)

1. NSF/ANSI/CAN 60 & 61 (2020) Drinking water system components – health effects

G. Sterrett, R.J. 2007. Groundwater and Wells. 3rd edition, New Brighton, MN. 812 p.

1.5 ADMINISTRATIVE REQUIREMENTS

1.5.1 NOTIFICATION

Notify the Government Point of Contact at least 30 days prior to drilling. The Government Point of Contact is responsible for contacting local, state, and federal regulatory agencies in accordance with the applicable reporting requirements. Before beginning work, notify the local United States

Geological Survey office and the New York DEC of the type and location of wells to be constructed, the method of construction and anticipated schedule for contraction of the well.

1.5.2 DELIVERY, STORAGE, AND HANDLING

Store and maintain well materials in a clean, uncontaminated condition throughout the course of the project. Do not allow filter pack material to freeze before installation.

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1.5.3 PROJECT AND SITE CONDITIONS

Access to each well site, including any utility clearance, permits, licenses, or other requirements and the payment thereof necessary for execution of the work, is the responsibility of the

Government. The Contractor shall furnish a copy of all required documents to Government at least 30 working days before commencement of the work. Obtaining rights-of-entry is the responsibility of the Government. Visit each proposed well location to observe any condition that may hamper transporting equipment or personnel to the site. If clearing or relocation is necessary, the Contractor and Government must agree on a suitable clearing, or relocation plan, and the location of any required access road.

1.5.4 WATER WELL DESIGN REQUIREMENTS

1.5.4.1 WELL INSTALLATION PLAN

Submit a plan as specified herein describing the drilling methods, sampling, and well construction and well development 60 calendar days prior to beginning drilling operations. Mobilization activities may start prior to submittal of the plan. The plan must be approved and signed by an experienced geologist as specified in paragraph QUALIFICATIONS. Incorporate the following requirements into the Well

Installation Plan and follow them in the field. The design of the well is to be based on the various aspects analyzed and contained in this plan (boring log, geophysical log, geotechnical report, sieve analysis, etc.). The plan must include, but not be limited to, a discussion of the following:

A. Description of well drilling methods, and installation procedures, including any temporary casing used, placement of filter pack and seal materials, drilling cuttings and fluids disposal, and soil and rock sample disposition.

B. Description of well construction materials, including well screen, riser pipe, centralizers, air line and gauge, filter pack and filter pack gradation, bentonite or drilling mud, drilling fluid additives, drilling water, cement, and well protective measures.

C. Description of quality control procedures to be used for placement of filter pack and seals in the boring, including depth measurements.

D. Forms intended for written boring logs, installation diagrams of wells, geophysical logs, well development records, well sampling data records, state well registration forms, and well abandonment records.

E. Description of contamination prevention practices for well materials and equipment decontamination procedures.

F. Description of protective cover surface completion procedures, including any special design criteria or features relating to frost heave prevention. Include the maximum frost penetration for the site in this description.

G. Description of intended well development methods.

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H. List of applicable publications, including state and local regulations and standards.

I. List of personnel assignments for this project, and personnel qualifications.

J. Description of well decommissioning or abandonment procedures.

K. Description of well capacity and aquifer testing techniques.

L. Description and discussion of geophysical techniques and camera surveying to be employed at the site.

M. Description of water quality sampling to be completed during aquifer testing.

N. Description of specific methods to be employed to control potential contamination or pollution arising from well installation activities.

O. Description of plumbness and alignment testing.

P. Description of specific methods employed to test for sand.

1.5.4.2 FORMATION SAMPLING

A. Frequency of sampling. Formation samples shall be obtained from the pilot hole at a maximum interval not exceeding 10 feet and at each change in formation. Particular care shall be taken when collecting samples from expected water producing zones.

B. Additional samples. At the direction of the Government, additional samples shall be obtained at a maximum interval of 5 feet, as required from expected water producing zones.

C. Collection and marking. Samples shall be collected, dried, and preserved in separate containers of at least 1.1-pound capacity for each interval. Containers shall be plainly marked with well designations, purchaser, location, depth interval, sampling method, sampler type, and the date and time the sample was taken.

D. Storage of samples. The constructor shall be responsible for the safe storage of formation samples until such time as they are accepted by the Purchaser.

E. Sample delivery. Time, place, and mode of delivery shall be as directed by the Government.

1.5.4.3 GEOPHYSICAL LOGGING

A. Geophysical borehole logging will be required following the completion of the pilot hole to provide qualitative information on aquifer composition and characteristics. Further specifications regarding geophysical logging are provided in this specifications document.

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1. Identification of principal aquifers shall be made by the Government and Site Engineer with assistance provided by Contractor and geologist using formation samples and geophysical borehole logging findings.

1.5.4.4 WATER SAMPLING AND ANALYSES

A. Water sampling. Water samples shall be taken for chemical analyses from each aquifer designated as a possible source for development. The method used to collect samples shall not contaminate the aquifer.

B. Water analyses. When designated, the analyses of the water shall be done according to requirements specified herein. Temperature, pH, specific conductance, and dissolved oxygen shall be determined by field test and recorded.

C. Water sampling requirements are further described in this specification document.

1.5.5 QUALIFICATIONS

Submit personnel qualification documentation. A geologist with at least three years of experience in soil and rock logging, and well installation, registered in the state of New York, must be on site during drilling, installation, and testing activities. Employ a driller licensed in the state of New York, according to the state requirements. Geophysical logs must be interpreted by a qualified log analyst.

Demonstrate the log analyst competence through background, training, and experience when so called upon. Document a minimum of 10 years of well installation experience.

1.6 SUBMITTALS

Government approval is required for submittals with a “G” or “S” classification. Submittals not having a “G” or “S” classification are for quality control approval. Submit the following in accordance with

Section 01 33 00 SUBMITTAL PROCEDURES:

SD-02 Shop Drawings

Installation Diagrams [G]

SD-03 Product Data

Well Material

Geophysical Logging

Cement and Bentonite Grout

Drilling Mud

Well Screens

SD-05 Design Data

Well Installation Plan [G]

SD-06 Test Reports

Water Source [G]

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Filter Pack

Capacity Test

Test for Plumbness and Alignment

Water Quality Test

Aquifer Test

Camera Survey

Sand Test

Other Tests, as Necessary

SD-07 Certificates

Site Conditions

Project Photographs

Qualifications

Casing

Air Line and Gauge

Graveling Equipment

Construction of Filter Pack

SD-11 Closeout Submittals

Survey Maps and Notes [G]

Well Development Records

Geophysical Logs

Hydrogeologic Report, as required by the State of New York

Decommissioning or Abandonment Record

The following submittals shall also be submitted by Contractor.

A. Qualifications

1. Submit proof that Contractor is licensed as required by Code of New York ECL §15-1525.

2. Provide information on and references for at least 5 similar well installations successfully completed.

B. Product Data

1. Submit product data for the following:

a. Casing: material, diameter, thickness and weight per foot of length.

b. Screen: material, construction, diameter and preliminary slot size.

c. Filter pack materials: material and specifications.

d. Grout: material and specifications.

e. Drilling fluids and/or additives to be used.

C. Methodology and Site Considerations

1. Indicate type and size of drilling equipment to be used along with indication of drilling method.

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2. Indicate erosion and sediment control methods to be used during drilling. Provide drawing and/or details as necessary to indicate disposal methods of water and sediment generated during drilling and development for approval by the Government and Site Engineer.

3. Indicate equipment and methodology used in test pumping to ensure that sand free test pumping of 120% of minimum design flow is maintained for continuous pumping operation.

PART 2 – PRODUCTS AND MATERIALS

2.1 MATERIAL REQUIREMENTS

A. Materials shall comply with the requirements of the Safe Drinking Water Act and federal regulations for potable water, wastewater, or reclaimed water systems, as applicable.

B. Toxicity levels. Products and components must not leach toxic substances into the water that is distributed to the public or the environment in their intended use. Disposal methods for residuals and used components that meet applicable regulatory requirements shall be available. Evaluation shall be accomplished in accordance with requirements that are no less restrictive than those listed in NSF/ANSI/CAN 60 or 61, respectively, if specified by the Government.

C. Drilling fluid materials. Drilling fluids are used in the process of drilling to facilitate the removal of formation cuttings and to stabilize the borehole during drilling and completion operations.

1. Types of drilling fluids. The following types of drilling fluids are acceptable for water well drilling:

a. Freshwater-based drilling fluids.

b. Air-based drilling fluids.

2. Fluid additives. Acceptable additives to drilling fluids are as follows:

a. Dissolved additives:

i. Mud-thinning agents.

ii. Inorganic phosphates.

iii. Surfactants.

iv. Drilling detergents.

v. Foaming agents.

vi. Natural and synthetic polymers.

b. Non-dissolved additives:

i. Native solids (clays and sands).

ii. Bentonite.

iii. Density-increasing materials.

iv. Loss-circulation materials (not to be used in the production zone).

D. Casing materials. All casing materials shall be new and shall conform to one of the manufacturing standards listed in AWWA Standard A100-20 Table 2. It shall be the responsibility of the

Contractor to ensure that the Purchaser is provided with documented mill certifications by the manufacturer for metallic casings.

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E. Well screen materials. To reduce the possibility of corrosion, metallic well screen and its fittings should be fabricated of the same material. This material shall be American Iron and Steel Institute

(ANSI) Type 304 stainless steel. A manufacturer’s certification of materials shall be provided to the Purchaser by the Contractor.

F. Filter pack material requirements.

1. Specific gravity. The filter pack material shall have an average specific gravity of not less than

2.5 and not more than 1% by weight of the material shall have a specific gravity of 2.25 or less.

2. Non-round pieces. Thin, flat, or elongated pieces, the maximum dimension of which exceeds three times the minimum, shall not be in excess of 2% by weight.

3. Acid solubles. Not more than 5% of the filter pack material shall be soluble in hydrochloric acid.

4. Washed material. The material shall be washed and free of shale, mica, clay, dirt, loam, and organic impurities of any kind.

5. Metals. The material shall contain no iron, manganese, copper, lead, or other heavy metals in a form or quantity that will adversely affect the quality of the well water.

6. Gradation. Tests for gradation of filter pack material shall be performed according to the method specified in ASTM C136.

7. Filter pack materials to formation ratio. Filter pack design shall be selected by Site Engineer and shall be based on filter pack selection methods outlined in Chapter 9 – Artificial Filter Pack of the third edition of Groundwater and Wells (Sterrett, 2007).

8. Uniformity coefficient. The uniformity coefficient of the filter pack shall not exceed 2.5.

9. Distribution curve. The size-distribution curve of the filter pack shall parallel the central part of the formation-sand distribution curve for formation sands having a uniformity coefficient of less than 2.5.

G. Grouting and sealing materials.

1. Neat cement. Neat cement shall consist of a mixture of ASTM C150, Type I or ASTM C150, Type II Portland cement and water in the ratio of not more than 6.0 gallons of water per 94-pound sack of cement weighing approximately 118 pounds per cubic foot.

a. A maximum of 6 percent, by dry weight, unbeneficiated (not enhanced or “high yield”) bentonite may be added to the neat cement grout. With bentonite additive, the mixture of cement and water should begin at the base ratio of 5.2 gallons of water per 94-pound sack of cement plus an additional 0.65 gallons of water per sack of cement for each 1% bentonite additive. Note also that the bentonite contribution to the mixture is affected by the mixing protocol, that is, whether the bentonite is mixed dry with the dry cement prior to adding mixing water or instead is added first to the mixing water (pre-hydrated) prior to the addition of cement. Pre-hydrated bentonite generates more effect, such that 1% of bentonite added first to the mixing water has the same effect as 3.6% of bentonite by dry weight mixed first with the dry cement.

The additional gallons of mixing water required (0.65 gallons of water for each 1% bentonite dry mixed) must be selected with consideration to the different mixing protocols and the relative effect of the bentonite in each protocol.

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2. Bentonite grout. Bentonite grout shall consist of a high-solids bentonite grout and water mixture with a minimum of 20% solids, mixed and placed in accordance with the manufacturer’s written instructions. Conventional bentonite drilling clay and water mixtures are not allowed. Such products shall not impart harmful characteristics to the well and shall be mixed and placed according to the manufacturer’s instructions.

2.2 WELL CASING

A. General. Well casing shall be continuous and watertight from top to bottom of the installed casing, except for well screens.

B. Surface casing shall be steel, 26-inch nominal diameter with 0.3125-inch wall thickness minimum and shall be installed to an estimated depth of 50 feet below ground surface.

C. Production casing shall be stainless steel (Type 304), 18-inch nominal diameter with 0.3125-inch wall thickness minimum and shall be installed from two feet above ground surface to an estimated depth of 350 feet bgs. The actual depth to which production casing shall be installed shall be determined by the Government and Site Engineer based on pilot hole formation samples and geophysical borehole logging findings.

D. Contractor shall measure each length of casing and record length to within 0.01 foot.

E. Steel joints shall be welded and shall be watertight.

F. Centralizers (centering guides) shall be placed between the production casing and boring wall at

60-foot intervals. Centralizers shall be made of the same material as that of the casing to which it is affixed.

2.3 WELL SCREEN

A. General. Screen lengths, screened depth intervals, and screen aperture size shall be determined by the Site Engineer based on pilot hole formation samples, formation sample sieve analysis data, and geophysical borehole logging results. Estimated parameters detailed in this specification sheet are preliminary and are subject to change at the discretion of the Government and Site

Engineer.

B. Well screen shall be wire-wound continuous-slot ANSI Type 304 stainless steel, 18-inch nominal diameter. The estimated screened interval is 350–400 feet bgs, although the actual screened interval will be determined by the Site Engineer. Screen slot (aperture) size shall be determined based on sieve analysis of formation samples by the Site Engineer. The Government and Site

Engineer shall be responsible for selecting formation samples that shall be analyzed using sieve analysis and the Contractor shall be responsible for performing sieve analysis and shall provide

Government and Site Engineer with results in the form of percent retained weight using the following sieve sizes: 4, 6, 8, 12, 16, 20, 30, 40, 50, 70, 100, 200, and PAN.

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C. Wire-wound continuous-slot screen. Continuous-slot wire-wound well screens shall be fabricated by circumferentially wrapping a triangular-shaped wire around an array of equally spaced rods.

Each juncture between the horizontal wire and the vertical rods shall be fusion welded underwater for maximum strength. The wire shape must produce inlet slots with sharp outer edges, widening inwardly to minimize clogging. Screen end fittings shall be fabricated of the same material as the screen body and shall be securely welded to each section.

D. Screen aperture size. Screen aperture openings shall be determined by Site Engineer based on pilot hole formation samples, formation sample sieve analysis data, and geophysical borehole logging results. Contractor shall not order screen materials until provided with specification information by Site Engineer.

E. Screen joints. Joints between screen sections and between screen sections and production casing shall be welded or threaded and coupled. If welded, the welding rod shall be of equal quality to the most noble metal. The joint shall be watertight, straight, and as strong as the screen.

F. Contractor shall measure each length of well screen and record length to within 0.01 foot.

G. Bottom of screen seal. The bottom of the deepest section of screen shall be sealed using a threaded or welded plate. The plate shall be installed at the bottom of the screen and shall be made of the same material as that of the screen (Type 304 stainless steel).

H. Centralizers shall be placed between the well screen and boring wall at 60-foot intervals.

Centralizers shall be made of the same material as that of the screen to which it is affixed.

2.4 FILTER PACK

A. General. Filter pack material shall be installed in the annular space between the screen (and limited sections of casing) and borehole for the purpose of stabilizing the formation. Filter pack intervals, annular thickness, and grain shall be determined by the Government and Site Engineer based on formation samples, sieve analysis results, and geophysical borehole logging findings.

Estimated parameters detailed in this specification sheet are preliminary and are subject to change at the discretion of the Government and Site Engineer.

B. Filter pack thickness and location. The minimum filter pack annular thickness shall be 3 inches.

Filter pack material shall be placed in the annular space adjacent to the well screens and shall extend above the screen for at least 25% of the length of the screened interval.

C. Filter pack samples. Samples of filter pack, including sieve analysis, shall be approved by the

Government in advance of delivery and placement.

1. Grain-size distribution. Grain-size distribution information provided by the supplier shall be based on sampling and sieve analysis completed within 90 days of submittal of this information to Government. If the filter pack supplier does not have available sieve analyses

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from within this period, then Contractor shall obtain a representative sample from the supplier for analysis by an independent laboratory.

a. All samples shall be plainly labeled to indicate the source of the material, the date, and the name of the supplier.

b. Filter pack materials shall be delivered to the jobsite sufficiently in advance of their scheduled emplacement in the well to allow for inspection and confirmation that the supplied grain-size distribution complies with that required for construction of the well. Prior to emplacement, representative composite samples equivalent to at least one sample for each 3 cubic yards of filter material delivered, but no less than two samples regardless of volume, shall be collected and submitted to an independent laboratory for sieve analysis.

c. Method of sampling. Method of sampling shall be according to ASTM D75 and

ANSI/AWWA B100. Particular care is required to obtain representative composite samples from bulk shipments and semi-bulk containers (i.e., bags of 1 cubic yard in size). ANSI/AWWA B100 suggests several protocols for representative sampling, by collecting samples from the center of the semi-bulk container using a thief sampler or by dumping portions of the filter materials in an open-top box and compositing.

2. Delivery and storage. The filter pack material shall be delivered to the well site on approval by the Government.

a. Bag or bulk delivery. The material may be delivered in bags or in bulk.

b. Contaminated material. Filter pack material that comes in contact with the ground surface shall not be used, and all materials shall be protected from contamination until installed.

PART 3 - EXECUTION

3.1 PREPARATION

3.1.1 PROTECTION OF EXISTING CONDITIONS

Maintain existing survey monuments and wells and protect them from damage from equipment and vehicular traffic. Repair any items damaged during this work. Reinstall wells requiring replacement due to Contractor negligence according to these specifications. Protect wells scheduled for abandonment from damage so that abandonment may be performed according to these specifications. Prior to commencement of drilling, obtain written approval from the local utility companies to drill at the site, to avoid disturbing buried utilities.

3.1.2 DECONTAMINATION

Clean the drill rig, drill rods, drill bits, augers, temporary casing, well developing equipment, tremie pipes, grout pumping lines, and other associated equipment with high-pressure hot water/steam prior to drilling at the well location. Decontaminate at a central decontamination station in an area that is remote from, and cross-or down-gradient from the well being drilled. Clean screen and well casing with high -pressure hot water immediately prior to installation in the well. The use of factory sealed

(plastic wrapped) screen and well casing does not waive this requirement for pre-installation cleaning.

Decontaminate samplers in accordance with the Well Installation Plan. Use water for cleaning from

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a Government approved source. Sample and test the water source used for cleaning for the constituents specified in the Sampling and Analysis Plan prior to use at the site.

3.1.3 WATER SOURCE

Submit decontamination and drilling water source analytical test results within 30 working days before beginning drilling operations. The Contractor is responsible for locating the source, obtaining the water from the source, transporting it to, and storing it at the site.

3.1.4 WELL SITE CONSIDERATIONS

A. Security of well site. At all times during the progress of the work, the Contractor shall use reasonable precautions to prevent either tampering with the well or the entrance of foreign material or surface water into the well.

B. Temporary capping of well. On completion of the well, the Contractor shall install a suitable threaded, flanged, or welded cap or compression seal to prevent foreign material from entering the well.

C. Height of casing aboveground. Unless otherwise specified by the Government, the casing shall extend at least 2 feet above the final ground level elevation and at least 2 feet above the 100-year flood level of record, whichever is higher.

D. Equipment placement. Any appurtenances that will permit direct, open access to the well shall also meet the height requirement of extending at least 2 feet above the final ground level elevation and at least 2 feet above the 100-year flood level of record, whichever is higher. Such appurtenances shall be sealed or screened to prevent entrance of foreign matter, surface water, or contaminants into the well.

E. Site grading. The ground immediately surrounding the well casing shall be sloped away from the well to prevent surface runoff from collecting around the completed well.

F. Limited space is available at the well site for drilling equipment and materials. Contractor shall use a steel tank drilling fluid containment system equipped with a shale shaker and sand separator to avoid the need to dig a mud circulation pit.

3.2 DRILLING, CONSTRUCTION AND TESTING

3.2.1 WELL DRILLING AND CONSTRUCTION

Locate the well where directed and construct in accordance with these specifications. Install the well to prevent aquifer contamination by the drilling operation and equipment, intra- and inter-aquifer contamination, and vertical seepage of surface water adjacent to the well into the subsurface, especially the well intake zone.

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If a well of the required capacity is not constructed, or if the well is abandoned because of loss of tools, or for any other cause, abandon the hole as specified and at the direction of the Government as specified in paragraph WELL DECOMMISSIONING OR ABANDONMENT.

3.2.2 GENERAL

A. Use the drilling method approved by the Government and in conformance with all state and local standards for water well construction. Execute the work under the direct supervision of an experienced well driller. The drilling method must prevent the collapse of formation material against the well screen and casing during installation of the well.

B. The inside diameter of any temporary casing used must be sufficient to allow accurate placement of the screen, riser, centralizers, filter pack, seal, and grout.

C. Use casing pipe, well screens, and joint couplings of compatible materials throughout each well.

3.2.3 PILOT HOLE DRILLING

A. Mud rotary drilling methods shall be used to drill the pilot hole.

B. Contractor shall drill a 7-7/8-inch diameter pilot hole to a depth of 410 feet bgs. Formation sampling of the pilot hole shall be performed in accordance with methods outlined within this document.

3.2.4 GEOPHYSICAL BOREHOLE LOGGING

A. Following the completion of pilot hole drilling and prior to the start of production borehole reaming, the Contractor shall conduct a full suite of geophysical borehole logging of the drilling fluid-filled boring to its total depth. Geophysical borehole logs should include the following, at a minimum: natural gamma, 16/64 short- and long-resistivity, spontaneous potential, and single point resistance. The Contractor will be provided with final well construction specifications, including production casing intervals and well screen aperture size and intervals, by the Site

Engineer within 10 business days of the Contractor’s submittal of geophysical logging and production zone sieve analysis results to the Site Engineer.

B. Following the completion of production borehole reaming, a caliper log shall be run from the bottom of the borehole to the top of the surface casing.

3.2.5 SIEVE ANALYSIS OF PRODUCTION ZONE FORMATION SAMPLES

A. The Government and Site Engineer shall be responsible for selecting formation samples collected from potential production zones during pilot hole drilling. Selected samples shall be analyzed using sieve analysis and the Contractor shall be responsible for performing sieve analysis and shall provide Government and Site Engineer with results in the form of percent retained weight using

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the following sieve sizes: 4, 6, 8, 12, 16, 20, 30, 40, 50, 70, 100, 200, and PAN. Digital copies of sieve analysis results and graphical copies shall be provided to Site Engineer.

3.2.6 BOREHOLE DRILLING/REAMING

A. Mud rotary drilling methods shall be used to ream the pilot hole.

B. A surface boring shall be drilled to a depth of 50 feet bgs to a minimum diameter of 32 inches using mud rotary drilling techniques.

C. A production boring shall be drilled to a depth of 410 feet bgs to a diameter of 24 inches using mud rotary drilling techniques. It shall be at the discretion of the Government and Site Engineer to determine whether formation sampling and geophysical borehole logging findings indicate that the production boring must be extended to a depth greater than 410 feet bgs.

D. Following the completion of production borehole reaming, a caliper log shall be run from the bottom of the borehole to the top of the surface casing.

3.2.7 BOREHOLE PLUMBNESS AND ALIGNMENT

A. General. Plumbness and alignment of the well must permit the successful installation and long-term operation of the permanent pumping equipment installed in the well. Tolerances presented in this subsection of the specifications shall apply for line-shaft pumps. If the well is to be equipped with a submersible pump, these specifications will not apply and the standard shall be that the pump is able to be freely installed in the well. Please refer to Government and Site

Engineer regarding the expected type of permanent pump.

B. Testing methods. Plumbness and alignment testing shall be completed in accordance with methods outlined in Appendix D of AWWA Standard A100-20.

C. Plumbness tolerance. The maximum allowable horizontal deviation (drift) of the well from the vertical shall not exceed 0.0067 times the smallest inside diameter of that part of the well being tested per foot of depth.

D. Alignment tolerance. The maximum misalignment, or “dogleg”, permissible is one that will allow a 40-foot long section of pipe to pass freely through it. The outside diameter of the test pipe shall be no smaller than ½-inch less than the inside diameter of the casing or borehole being tested.

E. Alternate alignment tolerance. Alternate alignment tolerance may be specified by the Purchaser after consideration of depth, formations, casing straightness, well diameter versus pump diameter, and local experience. The maximum allowable horizontal distance between the actual well centerline and a straight line representing the proposed pump centerline shall not exceed one-half of the difference between the inside diameter of the casing or borehole in the part of

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the well being tested and the desired maximum outside diameter of the proposed pump to be installed.

F. Depth of applied tolerances. The tolerances set forth in this subsection of the specifications shall apply from the top of the well to the bottom of the well.

3.2.8 DRILLING FLUIDS

A. During the drilling operation, when additives to freshwater are used, drilling fluid properties shall be maintained within limits that will allow their complete removal from the water produced from the well, if necessary, and shall not damage the potential capacity, efficiency, or quality of the well. Drilling fluid properties shall be maintained during normal drilling operations within the following limits using test procedures conforming to API RP 13B-2:

1. Weight (fluid density): Limits: 9.4–11.4 pounds/gallon. Test Equipment: mud balance.

2. Viscosity: Limits: 32–40 s/qt. Test Equipment: 1-qt mud cup, Marsh funnel, and stopwatch.

3. Filtration (wall cake and filtration loss): Limits: 3/32-inch with maximum 20-cc water loss in

30 minutes. Test Equipment: filter press, graduated cylinder, and stopwatch.

4. Sand content (solids larger than 200 mesh): Limits: 2–4% by volume. Test Equipment: sand-content set.

B. Frequency of drilling fluid property tests. Drilling fluid properties shall be tested once for every

50 feet of borehole drilled or four hours of circulating time, whichever is more frequent.

C. Recording. The drilling fluid properties set forth in this standard shall be measured and recorded.

3.2.9 WELL CASING AND SCREEN INSTALLATION

A. Well Casing and Screen Installation

1. The method of well casing installation shall be at the option of the Contractor, provided that the installation meets the plumbness and alignment specifications described herein, and the installation process does not alter the shape, size, configuration, or strength of the casing.

2. Casing and screen joints. Casing joints shall be welded or threaded and coupled in accordance with ANSI/AWWA C206.

3. Drive shoes. A steel drive shoe shall be used if the surface casing is to be pushed or driven.

Drive shoes shall be heat-treated SAE 1040 steel ring or equivalent.

4. Sealing of well casing. Well casing shall be sealed in accordance with grouting and sealing requirements described herein.

5. Well casing and screen shall be installed in the center of the borehole. Centralizers shall be placed every 60 feet along the production casing and screen to ensure concentricity.

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3.2.10 FILTER PACK PLACEMENT

A. Placement and Method. Filter pack material shall be placed using a tremie pipe to ensure continuity of the filter pack without bridging, voids, or segregation. Methods outlined in Appendix

B of AWWA Standard A100-20 shall be used to place filter pack material.

B. Filter pack thickness and location. The minimum filter pack annular thickness shall be 2 inches.

Filter pack material shall be placed in the annular space adjacent to the well screens and shall extend above the screen for at least 25% of the length of the screened interval.

C. Drilling fluid. Before the introduction of filter pack materials, the drilling fluid shall be reconditioned, unless different properties are needed, to protect the well, until it has the following properties:

1. Weight: A maximum of 9.1 pounds per gallon.

2. Viscosity: A maximum of 30 s/qt, determined by the API Marsh funnel test.

3. Sand content of fluid in the system: A maximum of 1% by volume.

D. Unusual drilling conditions. Where aquifer conditions make it necessary to continue drilling operations with drilling fluid that does not meet these standards, the drilling constructor shall be responsible for the completed removal of drilling fluid and development of the well.

E. Filter pack disinfection. The filter pack, as it is installed, shall be disinfected with a chlorine solution.

3.2.11 GROUTING AND SEALING

A. Methods. Sealing consists of filling the annular space between the casing and borehole with a substance that forms an impermeable seal. Grout shall be placed with a tremie pipe using methods outlined in Appendix C of AWWA Standard A100-20.

1. Cement grout sealing requirements. The annular space between the surface borehole and surface casing shall be sealed to a depth of 50 feet bgs using neat cement grout, as compositionally described in these specifications. Additionally, the annular space between the production casing and surface casing shall be sealed to a depth of 50 feet bgs using neat cement grout of the same composition.

2. Bentonite grout sealing requirements. The annular space between the production boring and production casing shall be sealed using bentonite grout, as compositionally described in these specifications. The depth interval(s) of bentonite grout placement shall be determined by Site

Engineer based on the depth intervals of screen and casing.

3. Thickness of annular seal. The annular space between the surface borehole and surface casing, as well as the space between the production borehole and production casing, shall be grouted and shall not be less than 2 inches in radial thickness.

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4. Methods of placement. Grouting shall be performed under pressure from the bottom upward in a continuous operation using a tremie pipe to ensure a complete seal of the annular space between the casing and the borehole.

5. Sealing of select zones. All zones containing water of undesirable quality or zones to be protected but excluded from final well completion shall be grouted from a point at least 5 feet above the zone to a point at least 5 feet below the zone. Notification of the need for sealing select zones will be provided by the Government.

6. Sealing of uncompleted borehole. In the event that a borehole must be abandoned, the sealing of the borehole shall occur using a neat cement grout slurry in accordance with the compositional requirements outlined in these specifications.

3.2.12 WELL DEVELOPMENT

A. Well development methods. Well development shall be completed using methods outlined in

Appendix E of AWWA Standard A100-20. Records related to well development shall also be kept in accordance with Appendix E of AWWA Standard A100-20. The methods of well development used by the Contractor shall minimally include mechanical surging, water/air jetting, and overpumping.

B. Completing development. Development shall continue until the following conditions have been met:

1. Sand content shall average not more than 2 mg/L for a complete pumping cycle of 2-hour duration when pumping at the designed discharge capacity.

2. No fewer than 10 measurements shall be taken at equal intervals to permit plotting of sand content as a function of time and production rate and to determine the average sand content for each cycle.

3. Development shall continue as long as the well’s specific capacity continues to increase significantly, at the discretion of the Government and Site Engineer. Additionally, the

Contractor shall effectively removal all drilling fluids from the well, especially those that may promote bacterial growth.

C. The final phase of development shall be done by use of the test pump used during aquifer testing.

D. The Contractor shall use a steel tank containment system or other means and methods necessary to provide settling and containment of material removed from the well. Water from such operations shall be piped to a point away from the well, as specified by Government, so it does not cause disruption of site activities.

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E. Final cleanup and restoration shall be completed by the Contractor in a timely manner following well completion.

3.2.13 DOWNHOLE CAMERA SURVEY

A. Following the completion of well development and prior to aquifer testing, a video-recorded downhole camera survey shall be completed from the top of the well’s casing to its total depth.

The camera shall be capable of viewing in a down-hole and side-view manner. Camera depth shall be visible at all times during the survey and shall be referenced to the top of the well’s production casing. The camera survey shall be repeated if the Site Engineer determines that water conditions are too turbid to evaluate the condition of the well. A sidewall view of the entirety of each casing and screen joint shall be recorded. The Site Engineer shall be present during surveying and shall provide direction to Contractor. Contractor shall provide Government and Site Engineer with a digital copy of the camera survey.

3.2.14 WELL DISINFECTION

A. General. The well shall be disinfected to remove bacteriological contamination that may cause the well water supply to be unsafe for human consumption. Disinfection shall be performed immediately prior to aquifer testing pump and sounding tube insertion. Refer to ANSI/AWWA

C654 for disinfection procedures.

B. Disinfection. The chlorine solution used for disinfecting the well shall be of such volume and strength and shall be so applied that a concentration of at least 100 mg/L of available chlorine shall be obtained for the entire water depth of the well, and this solution shall remain in the well for a period of at least 12 hours. The inside of the well casing above the standing water level shall also be washed with a chlorine solution of comparable concentration.

C. Overdosing requirement. If the samples collected after disinfection show bacteriological contamination, the Contractor shall prepare and apply to the entire depth of the well a total volume of the chlorine solution of at least 100 mg/L of available chlorine equal to at least four times the volume of water in the well. The Contractor shall allow this solution to remain in the well for a period of at least 24 hours.

3.3 AQUIFER PUMPING TESTS

3.3.1 TEST PUMP

A.