Hunter_specs.doc

ITEMS 3a, 3b, 3b(01), 4, 5, 8, 9 & 11a

SECTION 15207 - DOMESTIC WATER WELLS

ARTICLE 1 General Conditions

ARTICLE 2 Well Construction Procedure

2.0 Methods of Construction

2.1 Contractor's Choice

2.00 Drilling Fluid Control Program

2.01 Production Zone Protection

2.000 Driller's Logs and Reports

2.001 Well Log

2.002 Daily Drillers Report

ARTICLE 3 Well Casing, Selection, and Installation

3.0 Well Casing Selection

3.1 Steel Casing or Liner

3.2 Polyvinyl Chloride (PVC) Casing or Liner

3.00 Methods of Installation

3.01 Contractor's Choice

3.02 Jacking

3.03 Lowering

3.000 Methods of Joining

3.001 Contractor's Choice

3.000-0 Sanitary Protection of the Well

3.000-1 Termination at Top of Well

3.000-00 Casing Seating

3.000-01 Unconsolidated Formations

3.000-02 Consolidated Formations

3.000-000 Casing Backfill

3.000-001 Material

3.000-000-0 Casing Backfill Location

3.000-000-1 Unconsolidated Formations

3.000-000-2 Consolidated Formations

ARTICLE 4 Well Grouting

4.0 Grouting Materials

4.1 Concrete Grout

4.2 Sand-Cement Grout

4.00 Methods of Installing Grout

4.01 Bailer Dumping

4.02 Gravity Filling without Tremie

4.03 Gravity Filling with Tremie

4.04 Positive Displacement

ARTICLE 4 (Cont'd)

4.000 Location of Grout

4.001 Surface Formation Seal

4.002 Intermediate Grout Seal

4.003 Continuous Grouting

4.000-0 Centralizers

4.000-1 Contractor's Choice

ARTICLE 5 Well Screen and Slotted Casing

5.00 Slotted Casing/Well Screen Selection

5.01 Slotted Casing (Low Yield)

5.000 Slotted Casing/Screen Aperture Size

5.001 Contractor's Choice

5.000-0 Screen Length

5.000-1 Contractor's Choice

5.000-00 Slotted Casing/Screen Installation

5.000-01 Contractor's Choice

5.000-02 Pull Back Method

5.000-03 Suspended From Surface Method

5.000-000 Method of Joining Screen to Casing

ARTICLE 7 Well Plumbness and Alignment 7.0 Methods of Testing

7.1 Alignment

ARTICLE 8 Well Development 8.0 Surging and Bailing Method

8.1 Surging and Bailing (Utilizing Bailer)

8.2 Surging and Bailing (Utilizing Surge Block)

8.000-000-0 Sand Content Sampling

8.000-000-1 Contractor's Choice

8.000-000-00 Sand Limits

8.000-000-01 Practical Development

ARTICLE 9 Well Testing for Performance 9.0 Types of Pumping Tests Performed

9.1 Bailing Test Method

9.00 Pumping Rates

9.01 Single Tests

9.000 Recovery

9.001 Definition

9.000-0 Location of Discharge

9.000-1 Discharge of Water

9.000-00 Record of Pumping Tests

9.000-01 Records

9.000-000 Measurements of Water Levels

9.000-001 Contractor's Choice

ARTICLE 10 Well Disinfection 10.0 Disinfectants

10.1 Materials

10.00 Scheduling of Disinfection

10.01 Final Disinfection

10.02 Interm Disinfection

10.03 Daily Disinfection

10.000 Disinfection of Water Table/Nonflowing Artesian

Wells

10.001 Dry Chlorine Compounds

ARTICLE 11 Water Samples and Tests 11.0 Collection Methods

11.1 Point Sample

11.00 Well Head Tests

11.01 Temperature and pH Tests

ARTICLE 12 Well Abandonment 12.0 Aquifer Sealing Criteria

12.1 Disinfection

12.00 Permanent Bridges

12.01 General

12.000 Installation of Seal

12.001 Seal at Upper Most Aquifer

12.002 Intermediate Seal

12.003 Continuous Seal

12.000-0 Installation of Fill

12.000-1 Non-Producing Zone

12.000-2 Producing Zone

12.000-00 Well Abandonment Records

12.000-01 Records

ARTICLE 13 Method of Measurement and Payment 13.0 Pay Items

INDEX TO APPENDICES

AppendixB Well Log and Pump Installation Record

B1 Daily Drilling Record

D Pump Test Data Sheet

INDEX TO TABLES

Table 3.2 ARTICLE 3, PVC Water Well Casing/Liner

10.0 ARTICLE 10, Chlorine Compound Required to

Dose 100 Feet of Water-Filled Well at 100 ppm

DIVISION 15 - MECHANICAL

SECTION 15207 - DOMESTIC WATER WELLS

ARTICLE 1 - GENERAL CONDITIONS

1.1 SCOPE OF WORK: Provides for the construction, development, testing, disinfection, and water sampling of domestic water wells. The permanent well casing at the lowest point in the well shall not be less than six inches (nominal) in diameter and the wells are expected to be approximately 120 to 200 feet in depth

1.2 TEST PUMPING: Upon completion of well development, the well shall be pumped in accordance with

Article 9 to determine the final Well yield (gpm).

1.3 WELL PRODUCTION RATE: The desired sustained well production rate, after installation of the proposed pump, in accordance with Article 1.2, is five or more gpm.

1.4 WELL ABANDONMENT: The GOVERNMENT may direct the CONTRACTOR, in writing, to abandon the well if, in the opinion of the GOVERNMENT, (1) the amount of water encountered during the drilling process indicates it is highly improbable that a minimum sustained well production rate of five gpm can be obtained by drilling to 140 feet; and/or (2) the obvious quality of the water (taste, soap, color, and odor), after visual inspection by the GOVERNMENT, is not suited for domestic consumption.

1.5 WELLHEAD DEVELOPMENT: Wellhead development shall consist of watertight sanitary well seal 18 inches above the natural ground. Installation of a concrete grade slab around the well casing shall be required on those wells specified in the Schedule of Items.

1.6 LOCATION: The approximate location of the proposed well is shown on the attached maps exact locations will be staked on the ground.

1.7 ACCESS: Good quality roads provide access to the sites. Minor site clearing and grading may be required before drilling. Materials and equipment storage at the site shall be permitted during work progress but will be at the CONTRACTOR'S risk.

1.8 SUBSURFACE: The general area of the well site is assumed to be underlain by unconsolidated and/or consolidated material. No geological investigation has been made.

1.9 MISCELLANEOUS: All work shall be in accordance with this specification and the Wyoming Water

Well Minimum Construction Standards. The most stringent of the two, as determined by the GOVERN

MENT, shall apply.

All construction materials, equipment, and debris shall be removed from the site upon completion of the work.

1.10 SAMPLES, TESTS, AND REPORTS: Samples, Tests, and Reports that shall be the responsibility of the

CONTRACTOR shall include: (Appendix shown for convenience of CONTRACTOR):

A. Well Log and Pump Installations Record (Appendix B).

B. Daily Drillers Report (Appendix B1).

C. Well Test for Performance and measuring drawdown/ recovery levels and time (Appendix D).

The CONTRACTOR shall submit filled-out copies of Appendices B, B1, and D to the GOVERNMENT upon completion of this contract. Submittal of Appendix B shall be subject to the provisions of Article 2.001.

ARTICLE 2 - WELL CONSTRUCTION PROCEDURE

2.0 METHODS OF CONSTRUCTION

2.1 CONTRACTOR'S CHOICE. The CONTRACTOR shall choose the construction method(s) to be used.

These are:

Cable Tool (Percussion)

Conventional Fluid Rotary Drilling

Reverse Circulation Rotary Drilling

Air Rotary Drilling

2.00 DRILLING FLUID CONTROL PROGRAM

2.01 PRODUCTION ZONE PROTECTION. Material used by CONTRACTOR to prepare the drilling fluid shall be composed of fresh, nonpolluted water and an approved commercial agent applied and used as prescribed by the manufacturer. Toxic and/or dangerous substances shall not be added to the drilling fluid.

A. The CONTRACTOR shall be responsible for maintaining the quality of the drilling fluid to assure (1) protection of water bearing and potential water bearing formations exposed in the bore hole, and (2) good representative samples of the formation materials.

B. The drilling fluid properties required shall depend on: (1) the type and size of drilling equipment to be used, and (2) down hole conditions anticipated or encountered.

1. Mud density: The density should be in the range of nine pounds per gallon. It may be higher if necessary to control a high formation pressure.

2. Mud viscosity: The viscosity should be kept as thin as practical and still retain formation stability and adequate hole cleaning. This will depend on ascending velocity in the annulus and is usually in the range of 30 to 40 seconds per quart for properly sized drilling equipment and in normal drilling situations.

3. Sand content: Should not exceed two percent by volume.

2.000-DRILLER'S LOGS AND REPORTS

2.001 WELL LOG. During the drilling of the well the Contractor shall prepare and keep a complete log setting forth, the following (See Appendix B):

1. The reference point for all depth measurements.

2. The depth at which each change of formation occurs.

3. The depth at which the first water was encountered.

4. The identification of the material of which each for-mation is composed, such as:

a. Clay

b. Sand or Silt

c. Sand and Gravel. Indicate color and whether gravel is loose, tight, angular, or smooth.

d. Cemented formation. Indicate whether grains (if present) have natural cementing material between them; e.g. silica, calcite, etc.

e. Hard rock. Indicate whether sedimentary bedrock, or igneous (granite-like, basalt-like, etc.).

5. The depth interval from which each water and formation sample was taken.

6. The depth at which hole diameters (bit sizes) change.

7. The depth to the static water level (SWL) and changes in SWL with well depth.

8. Total depth of completed well.

9. The depth of intermediate and/or surface seals, as applicable.

10. The amount of cement (number of sacks) placed for each seal, as applicable.

11. The depth and description of the well casing.

12. The description (to include length, diameter, slot size, material, and manufacturer) and location of well screens, or number, size, and location of perforations.

13. The sealing off of water-bearing or undesirable formations, if any, and the exact location of such seals.

The CONTRACTOR shall submit a copy of the well log to the GOVERNMENT upon completion of the work (See Appendix B). If the state has a standard well log form, the CONTRACTOR may submit a copy of such form in-lieu of Appendix B.

2.002 DAILY DRILLER'S REPORT. During the drilling of the well, a Daily Driller's Report shall be maintained and submitted to the GOVERNMENT upon completion of the Contract. The report shall give a complete description of all formations encountered, number of feet drilled, number of hours on the job, shutdown due to breakdown, the water level in the well at the beginning and end of each shift, the water level at each change of formation if readily measurable with the drilling method used, feet of casing set, location of any lost drilling tools or fluid, and such other pertinent data as requested by the GOVERNMENT. In rotary drilling, the fluid level in the hole shall be measured daily prior to starting pumps (See Appendix B1).

ARTICLE 3 - WELL CASING SELECTION AND INSTALLATION

3.0 WELL CASING SELECTION

3.1 STEEL CASING OR LINERS. Black steel, minimum six inches (nominal) diameter complying with either ASTM A-53 or A-120, in minimum lengths of five feet. Minimum wall thickness shall be in accordance with Table 3.1. Steel casing or liner, when required, shall be shown in the Bid Schedule.

3.2 POLYVINYL CHORIDE (PVC) CASING OR LINERS. Minimum six inches (nominal) diameter, complying with either ASTM D-2241 or F-480. Minimum wall thickness shall comply with Table 3.2. PVC casing, or liner when required, shall be shown in the Bid Schedule.

3.00 METHODS OF INSTALLATION

3.01 CONTRACTOR'S CHOICE. The method of installing casing, either temporary or permanent, shall be left to the CONTRACTOR'S discretion; however, the method shall be compatible with the type of casing being installed, drilling method used, and formations encountered.

A. PVC casing shall not be extended above the ground unless contained within a steel casing.

B. Telescoping casing (progressively reducing casing diameter with depth of well) shall be permitted;

however, the minimum diameter of casing measured at the lowest point in the well, shall be six inches (nominal).

C. Liner may be used, in-lieu of casing when drilling through a consolidated formation.

3.02 JACKING. A pulldown spread footing shall be installed around the well and the jacking force on the casing achieved by pulling down on the casing with the ram end of hydraulic jacks while the cylinder end is secured to the spread footing. PVC casing shall not be used when jacking of the casing is required.

Telescoping casing (progressively reducing casing diameter with depth of well) shall be permitted;

however, the minimum diameter of casing, measured at the lowest point in the well shall be six inches

(nominal).

Liner may be used in-lieu of casing when drilling through a consolidated formation.

3.03 LOWERING. The lowering method is used to install a jointed casing string in a predrilled hole. The casing shall be lowered with the drilling machine, utilizing clamps, elevators, or other mechanical devices.

Telescoping casing (progressively reducing casing diameter with depth of well) shall be permitted;

however, the minimum diameter of casing, measured at the lowest point in the well, shall be six inches

(nominal).

Liner may be used in-lieu of casing when drilling through a consolidated formation.

3.000 METHODS OF JOINING

3.001 CONTRACTOR'S CHOICE. Casing lengths shall be joined watertight by a method appropriate to the material used. The resulting joint shall have the same structural integrity as the casing.

A. If metallic casing is welded, the standards of the American Welding Society shall apply.

B. If threaded and coupled joints are used, couplings shall be API or equivalent, made up so that when tight all threads will be buried in the lip of the coupling.

C. Plastic casing sections shall be joined watertight by either solvent welding or by the use of threaded and coupled joints. It is common practice to secure solvent welded joints with screws to prevent separation before full cure. Screws shall be permitted; however, screws shall not penetrate into the interior of the casing.

3.000-0 SANITARY PROTECTION OF WELL

3.000-1 TERMINATION AT TOP OF WELL. At all times during the progress of the work, until completion of the well or termination of Contract, the CONTRACTOR shall use reasonable precautions to prevent contamination of the aquifer due to either tampering with the well or the entrance of foreign material.

A. Upon completion of the well, the CONTRACTOR shall install a threaded, flanged, welded, or compression sanitary seal to prevent any pollutants from entering the well.

B. The sanitary seal shall be installed at the upper terminus of the permanent well casing. The permanent well casing shall extend at least 18 inches above the finished ground elevation or as otherwise specified in Article 1.6. The finished ground surface around the permanent casing shall be graded to slope away from the well.

3.000-00 CASING SEATING

3.000-01 UNCONSOLIDATED FORMATIONS. The casing is supported by the collapse and compaction of the drill hole during removal of the outer temporary casing. The completion of the sanitary surface grout seal will also assist in supporting the casing.

3.000-02 CONSOLIDATED FORMATIONS. The casing shall extend at least five feet into the formation to assure a proper seat and bottom seal. It shall be the responsibility of the CONTRACTOR to effect a proper seal. When the casing is to be lowered (rather than jacked), cement grout shall be placed in the annular space between the drill hole and casing, for the full seated depth, in accordance with Article 4.

3.000-000 CASING BACKFILL

3.000-001 MATERIAL. Casing backfill material, when required, shall be clean sand, cement-sand, formation stabilizer, or artificial filter material as appropriate. Size and gradation of all materials, except cement-sand, shall be approved by the GOVERNMENT.

3.000-000-0 CASING BACKFILL LOCATION

3.000-000-1 UNCONSOLIDATED FORMATIONS. Casing backfill shall not be required.

The casing is supported by the collapse and compactions of the drill hole during removal of the outer temporary casing.

3.000-000-2 CONSOLIDATED FORMATIONS. Casing backfill material shall be required from the top of the aquifer or top of the artificial filter material to the lower limit of the surface grout seal. When continuous grouting is required in accordance with Article 4, casing backfill shall not be required.

Bridging shall not be permitted except as provided in Article 12.

ARTICLE 4 - WELL GROUTING

4.0 GROUTING MATERIALS

4.1 CONCRETE GROUT. Grout shall be a mixture of Portland Cement (ASTM C150), sand, coarse aggregate, and water. The concrete yield shall not be more than 5.4 cubic feet of concrete per 94 pound sack of cement. The water-cement ratio shall not exceed 0.53. The use of special cements; bentonite to reduce shrinkage, or other admixtures to reduce permeability, increase fluidity, control time of set, and the composition of the resultant slurry; must be approved by the GOVERNMENT.

4.2 SAND CEMENT GROUT. Grout shall be a mixture of Portland Cement (ASTM C150), sand, and water.

The sand-cement ratio shall not be more than two parts by weight of sand to one part by weight of cement.

The water-cement ratio shall not exceed 0.53. The use of special cements; bentonite to reduce shrinkage, or other admixtures to reduce permeability increase fluidity, control time of set, and the composition of the resultant slurry; must be approved by the GOVERNMENT.

4.00 METHODS OF INSTALLING GROUT

4.01 BAILER DUMPING. Grout material shall be placed into the annular space by lowering the grout material to the bottom of the hole in a bailer, and dumping (after water or other drilling fluid has been circulated in the annular space sufficient to clear obstructions). The bailer shall not be dumped more than one foot from the bottom of the hole, and a time of no more than ten minutes shall elapse between dumps in a single plug. Curing time before construction may be resumed: Portland Cement Type I-minimum 72 hours;

Type III-minimum 36 hours.

During placement of grout the permanent casing shall be vibrated or turned to assist grout settlement.

4.02 GRAVITY FILLING WITHOUT TREMIE. Grout material shall be uniformly poured into the annular space without the aid of a tremie or grout pipe (after water or other drilling fluid has been circulated in the annular space sufficient to clear obstructions). This method shall be used only where the interval to be grouted is clearly visible from the surface and is dry.

Maximum allowable depth to bottom of grout interval shall be 20 feet. Curing time before construction may be resumed: Portland Cement, Type I-72 hours minimum, Type III-36 hours minimum.

During placement of grout the permanent casing shall be vibrated or turned to assist grout settlement.

4.03 GRAVITY FILLING WITH TREMIE. Grout material shall be placed by tremie pouring (after water or other drilling fluid has been circulated in the annular space sufficient to clear obstructions). The tremie method shall only be used where there is a minimum annular space of three inches. The minimum size tremie pipe utilized shall be two inches inside diameter. Where concrete grout is used the minimum size tremie pipe used shall be three inches inside diameter. When making a tremie pour, the tremie pipe shall be lowered to the bottom of the zone being grouted, and raised slowly as the grout material is introduced.

The tremie pipe shall be kept full continuously from start to finish of the grouting procedure, with the discharge end of the tremie pipe being continuously submerged in the grout until the zone to be grouted is completely filled. Curing time before construction may be resumed: Portland Cement Type I-minimum

72 hours; Type III-minimum 36 hours.

During placement of the grout the permanent casing shall be vibrated or turned to assist grout settlement.

4.04 POSITIVE PLACEMENT. Grout material shall be placed by a positive displacement method such as pumping for forced injection by air pressure (after water or other drilling fluid has been circulated in the annular space sufficient to clear obstructions). Grout shall be injected in the annular space between the inner casing and either the outer casing or the borehole. The annular space must be a minimum of 1 1/2 inches for sand-and-cement grout, and not less than three times the size of the largest coarse aggregate used for concrete grout. The grout pipe shall extend from the surface to the bottom of the zone to be grouted. The grout pipe shall have a minimum inside diameter of one inch for sand-cement grout. It shall have a minimum diameter of 1 1/2 inches for concrete grout. Grout shall be placed, from bottom to top, in one continuous operation. The grout pipe may be slowly raised as the grout is placed but the discharge end of the grout pipe must be submerged in the emplacement grout at all times until grouting is completed. The grout pipe shall be maintained full, to the surface, at all times until the completion of the grouting of the entire specified zone. In the event of interruption in the grouting operations, the bottom of the pipe should be raised above the grout level and should not be resubmerged until all air and water have been displaced from the grout pipe and the pipe flushed clean with clear water. Curing time before construction may be resumed: Portland Cement Type I-minimum 72 hours; Type II-minimum 36 hours.

During placement of the grout the permanent casing shall be vibrated or turned to assist grout settlement.

4.000 LOCATION OF GROUT

4.001 SURFACE GROUT SEAL. The annular space to be grouted, at the upper terminus of the well, shall not be less than one inch. The effective length of seal, as defined here, shall not be less than 40 feet or the minimum specified by the state which ever is greater. The entire space to be grouted must be open and available to receive the grout at the time the grouting operation is performed. If a temporary casing was installed to keep the entire space open (in unconsolidated materials), the temporary casing shall be removed as the grout is installed.

The effective length of grout seal (for sanitary purposes) shall be that distance measured from the deepest limit of the seal up to the depth of frost penetration. If a pitless adapter or unit is to be installed in accordance with Article 1.6, the upper limit of the seal shall be one foot below the field connection of the proposed adapter or unit. The grout seal shall not be extended to the ground surface unless required by state law.

The depth of frost penetration shall be determined by the GOVERNMENT.

4.002 INTERMEDIATE GROUT SEAL. Zones containing water, gas, or other unsuitable material, as determined by the GOVERNMENT, shall be grouted from five feet below, to a point at least five feet above, the unsuitable zone. The annular space surrounding the casing between grouted zones shall be filled with casing backfill material complying with Article 3.

4.003 CONTINUOUS GROUTING. Grouting shall be continuous from the bottom of the permanent casing to the depth of frost penetration; or, where an artificial filter has been installed, from the top of the filter to the depth of frost penetration; or, where a well screen or slotted casing has been installed, from a point five feet above the screen or slotted casing to the depth of frost penetraiton. When a pitless adapter or unit is to be installed in accordance with Article 1.6, the grout shall extend from such depth to within one foot of the field connection of the proposed adapter or unit.

If a temporary casing was installed to keep the entire space open (in unconsolidated materials), the temporary casing shall be removed as the grout is installed. The grout seal shall not be extended to the ground surface unless required by state law.

The depth of frost penetration shall be determined by the GOVERNMENT.

4.000-0 CENTRALIZERS

4.000-1 CONTRACTOR'S CHOICE. The need for centralizers and the type and location of centralizers shall be at the CONTRACTOR'S discretion.

ARTICLE 5 - WELL SCREEN AND SLOTTED CASING

5.00 SLOTTED CASING/WELL SCREEN SELECTION

5.01 SLOTTED CASING (LOW YIELD). Slotted casing shall be machine slotted. The slots shall be equal in width and of uniform spacing and dimensions. Slotted casing shall be the same diameter and material as permanent casing.

5.000 SLOTTED CASING/SCREEN APERTURE SIZE

5.001 CONTRACTOR'S CHOICE The aperture size shall be the responsibility of the CONTRACTOR.

5.000-0 SCREEN LENGTH

5.000-1 CONTRACTOR'S CHOICE. The CONTRACTOR shall select the slotted casing length and interval to be screened. In no case shall the slotted casing length be less than three feet nor more than ten feet without prior written approval by the Government.

5.000-00 SLOTTED CASING/SCREEN INSTALLATION

5.000-01 CONTRACTOR'S CHOICE. The slotted casing shall be installed using any method deemed appropriate by the CONTRACTOR.

5.000-02 PULL BACK METHOD. The well casing shall be carried through the formation to be screened and cleaned out to the level where the bottom of the screen is to be placed. The screen shall then be lowered to that level by means of a cable attached by a hook to the bail in the bottom of the screen, or by attaching a pipe with the screen. The screen can also be placed by gravity under conditions that limit the rate of descent. After the screen is in its proper location, a heavy steel bar or line of pipe may be set on the screen bottom to hold it down and the casing shall be raised until the screen is exposed to the aquifer with the packer located not less than 12 inches into the casing.

5.000-03 SUSPENDED FROM SURFACE METHOD. The screen, with closed bottom, shall be attached in an approved manner to the casing and lowered into the well with the casing. In no instance shall it be driven or forced. It shall remain suspended from the surface until the formation has collapsed against it or until artificial filter material or casing backfill has been installed.

ARTICLE 7 - WELL PLUMBNESS AND ALIGNMENT

7.0 METHODS OF TESTING

7.1 ALIGNMENT. The completed well shall be sufficiently straight so that there will be no interference with installation, operation, or future removal of the proposed well pump specified in Article 1.

Alignment shall be tested by lowering into the well, for the full depth of the well, a section of pipe 20 feet long, or a dummy of the same length. When the diameter of the permanent well casing decreased with well depth, the test pipe or dummy section shall be sized as follows:

When Article 1 indicates future installation of a pump other than a line shaft turbine, the outer diameter of the test pipe or dummy section shall be sized for the permanent casing having the smallest inside diameter.

When the diameter of the permanent well casing is constant for the entire depth of the well, the outer diameter of the test pipe or dummy section shall be sized for the inside diameter of the permanent well casing.

When the nominal diameter of the permanent casing being tested is ten inches or less, the outer diameter of the test pipe or dummy section shall not be more than 1/2 inch smaller than the inner diameter of the permanent casing.

The test pipe or dummy section, when lowered into the casing being tested, shall pass freely the entire depth of the test section.

ARTICLE 8 - WELL DEVELOPMENT

8.0 SURGING AND BAILING METHOD

8.1 SURGING AND BAILING (UTILIZING BAILER). The development process shall include surging and bailing the well. Surging shall be accomplished by utilizing the bailer as a surging device. Development shall start at the bottom of the well and proceed upwards. On completion of development the well shall be cleaned to the bottom.

8.2 SURGING AND BAILING (UTILIZING SURGE BLOCK). The development process shall include surging and bailing the well. The surging shall be done by a single or double, solid or valved, surge block.

Surging shall start at the bottom of the well and proceed upwards. On completion of development the well shall be cleaned to the bottom.

8.000-000-0 SAND CONTENT TESTING

8.000-000-1 CONTRACTOR'S CHOICE. The number, frequency, volume, location, and method of taking water samples for determining sand content shall be the CONTRACTOR'S discretion.

8.000-000-00 SAND LIMITS

8.000-000-01 PRACTICAL DEVELOPMENT: Well development shall continue until, in the opinion of the

GOVERNMENT, the sand content can not be reduced with further development.

ARTICLE 9 - WELL TESTING FOR PERFORMANCE

9.0 TYPES OF PUMPING TEST PERFORMED

9.1 BAILING TEST METHOD. The CONTRACTOR shall measure the static water level in the well. The

CONTRACTOR shall select a bailer of known volume only slightly smaller than casing, and calculate or measure and record its volume. The well shall be bailed until the drawdown is at least 20 feet above the bottom of the well. The bailer shall then be lowered until it hits the drawdown level. The bailing line shall be marked at a point level with the top of the casing when the bottom of the bailer just touches the water. A second mark shall be made one bailer length above the first. Rhythmically bailing, the CONTRACTOR shall lower the line precisely to the second mark on the cable each time, noting the elapsed time per round trip.

The bailer shall be full each time it emerges from the well. If the bailer is not full, it shall not be lowered deeper; however, the rate of bailing shall be slowed until the bailer comes out full each time. The bailing rate, in gallons per minute, equals the volume (gal) of the bailer divided by the time (min) per round trip.

If the depth of water in the well is less than the length of the bailer, the CONTRACTOR shall measure the amount of water in the bailer and relate it to a timed interval of one minute for each time the bailer leaves the bottom of the well.

The static water level, the stabilized pumping water level, and the well yield (gpm) shall be measured and recorded. Recovery measurements shall comply with ARTICLE 9.000-001. Drawdown measurements between static water level and stabilized pumping water level shall not be required (See Appendix D).

9.00 PUMPING RATES

9.01 SINGLE TEST. A single pump test to determine the well yield (gpm) shall be conducted at ten gpm.

Another pumping rate may be approved by the GOVERNMENT in accordance with Article 1.4.

9.000 RECOVERY

9.001 DEFINITION. Recovery shall be considered "complete" after any three successive water level measurements spaced at least 20 minutes apart show no further rise in the water level in the pumped well.

9.000-0 LOCATION OF DISCHARGE

9.000-1 DISCHARGE WATER. Discharge water shall be conducted from the pump, to a location approved by the GOVERNMENT, through approved piping or lined ditches to prevent recirculation of discharged water into the aquifer being tested. The distance of such piping or ditches, from the well, shall not be less than 20 feet or more than 100 feet.

9.000-00 RECORD OF PUMPING TESTS

9.000-01 RECORDS. The CONTRACTOR shall keep accurate records of the pumping test and furnish copies to the GOVERNMENT upon completion of this Contract (See Appendix D). The records shall also be available to the GOVERNMENT for inspection at any time during the test. Records shall include, but not limited to: a description of the measuring point and its measured height above land surface and/or mean sea level, the methods used in measuring water levels, the date of the test, the clock time and elapsed pumping time of each drawdown and/or recovery measurement, the depth of water below the measuring point, the pumping rate at the time of measurement, and any pertinent comments on the conditions that may affect the measurements.

Frequency of water-level measurements before, during, and after pumping shall be as specified by the

GOVERNMENT or as specified in Article 9.000-001 when applicable.

9.000-000 MEASUREMENTS OF WATER LEVEL

9.000-001 CONTRACTOR'S CHOICE. The method of taking water level measurements shall be at the discretion of the CONTRACTOR; however, accuracy to within plus or minus .10 feet must be attained.

The static water level shall be measured prior to the start of the test. Drawdown shall be measured according to the following schedule: 0 to 10 minutes every minute; 10 to 45 minutes every five minutes; 45 to 90 minutes every 15 minutes; 90 to 180 minutes each half hour; 180 minutes to the end of the test each hour. Should the measurements not be made exactly at the times specified, the actual time of each measurement shall be recorded. On completion of pumping, recovery measure ments shall be made according to the above drawdown schedule (See Appendix D).

ARTICLE 10 - WELL DISINFECTION

10.0 DISINFECTS

10.1 MATERIALS. Chlorine or other disinfectants, approved by the GOVERNMENT shall be used as disinfectants. The disinfectant shall be delivered to the job site in original closed containers bearing the original label indicating the percentage of available chlorine. The quantity of chlorine compounds used for disinfection shall be sufficient to produce a minimum of 100 ppm (parts per million) available chlorine in solution when mixed with the total volume of water in the well. A 100 ppm solution should result from utilizing quantities of chlorine compounds, proportion to the depth of water, as listed in Table 10.0.

10.00 SCHEDULING OF DISINFECTION

10.01 FINAL DISINFECTION. The CONTRACTOR shall provide for disinfection as soon as construction of the well and cleaning procedures have been completed. The CONTRACTOR shall carry out adequate cleaning procedures immediately preceding disinfection. All oil, grease, soil, and other materials shall be removed from the well. Unless the GOVERNMENT approves unusual cleaning methods, the cleaning operation shall be by pumping and swabbing only. Where test pumping equipment is to be utilized, such equipment shall be installed prior to or during disinfection and be thoroughly hosed, scrubbed, or otherwise cleaned of foreign material and before installation in the well.

10.02 INTERIM DISINFECTION. Should a delay of three days or more be anticipated between the comple tion of the well and the regularly scheduled well disinfection, interim disinfection shall be provided by the CONTRACTOR. The CONTRACTOR shall install an approved disinfecting agent in an amount equal to ten percent of the amount required for final disinfection. For this purpose the disinfecting agent shall be furnished or prepared in liquid form and placed in the well through a hose or tremie of sufficient length to extend to the bottom of the well. The disinfecting agent shall be applied through the hose, which is to be raised and lowered, to achieve uniform distribution of the solution throughout the well.

10.03 DAILY DISINFECTION. Daily disinfection of the well shall be carried out by the CONTRACTOR during drilling operations. The CONTRACTOR and GOVERNMENT shall agree on the amount of disinfecting agent to be used and the application method in advance of initiating the work.

10.000 DISINFECTION OF WATER TABLE/NONFLOWING ARTESIAN WELLS

10.001 DRY CHLORINE COMPOUNDS. All accessible portions of the well above the water level shall be maintained in a moist condition with water containing the required concentration of disinfecting agent for a period of not less than 20 minutes.

A doubly capped, perforated pipe container, filled with the appropriate amount of a granular chlorine compound for the well, shall be moved up and down the entire well bore until the material has dissolved.

After the disinfectant is in place, dispersion of the disinfectant shall be assisted by pouring into the well a volume of clear water equal to the volume of water in the well casing. This will cause the disinfectant to flow out of the well into the area adjacent to the screen.

The disinfecting agent shall be left in the well for a period of at least 12 hours. After the 12 hour, or longer, contact period the well shall be pumped to clear it of the disinfecting agent.

The disposal point for the purged water shall be in accordance with ARTICLE 9.000-1, and shall minimize potential damage to aquatic life or vegetation.

10.002 PREPARED SOLUTION. A chlorine solution of the appropriate concentration to disinfect the well shall be prepared on the surface in containers having an aggregate volume equal to at least twice the volume of water in the well and then rapidly discharged into the well so as to thoroughly flush that portion of the casing which is above the water level.

The disinfecting agent shall be left in the well for a period of at least 12 hours. After the 12 hour, or longer, contact period the well shall be pumped to clear it of the disinfecting agent.

The disposal point for the purged water shall be in accordance with Article 9.000-1, and shall minimize potential damage to aquatic life or vegetation.

10.000-0 DISINFECTION OF FLOWING ARTESIAN WELLS

10.000-1 DRY CHLORINE COMPOUNDS. A doubly capped, perforated pipe container filled with a granular chlorine compound shall be placed at a point at or below the top of the producing zone. This process shall be repeated as often as necessary to achieve and maintain the standard 100 ppm concentration for a period of not less than one hour.

ARTICLE 11 - WATER SAMPLES AND TESTS

11.0 COLLECTION METHODS

11.1 POINT SAMPLE. After well development, disinfection, and testing for performance, and after all traces of disinfectant are removed from the well, the GOVERNMENT shall take one or more one gallon water sample(s) for physical/chemical analysis and two 500 ml samples for a bacteriological analysis. The

CONTRACTOR shall provide the pumping equipment required to permit the sampling.

Sample containers shall be provided by the GOVERNMENT. The GOVERNMENT shall pay all costs related to the analysis of the sample including all transportation charges to and from the laboratory.

11.00 WELL HEAD TESTS

11.01 TEMPERATURE AND pH TESTS. The temperature and pH of the water shall be determined by the

GOVERNMENT immediately upon collection of the water sample and recorded on the sample container and well log (Appendix B). Tests shall be conducted according to procedures prescribed by the manufacturer of the test equipment employed, local health or water agencies, or as set forth in standard publications dealing with this method of analysis.

ARTICLE 13 - METHOD OF MEASUREMENT AND PAYMENT

13.0 PAY ITEMS

The accepted quantities of work will be measured as shown below and paid for at the contract bid price as shown on the Schedule of Items.

Article Title

Method of Payment

Well Construction Payment for this item is

Procedure included under Article 3a.

3a Drilling Payment shall be at the contract bid price per linear foot of drilled hole of the specified size.

The drill hole shall be measured from the natural ground or from start of hole diameter to the final depth. Payment shall include materials, labor, and equipment for drilling; well log; drilling fluid; well plumbness and alignment; test pumping and related water samples; and installation/removal of temporary

(outer) casing.

3b Well Casing linear foot of casing installed, and of the specified type and size. Casing shall be measured vertically end to end for each type and size. Payment shall include materials and labor for installation, joining casing sections, sanitary well seal, site grading around the casing, sealing, and casing backfill.

Surface Grout Payment shall be at the contract bid price

Seal per linear foot of grout installed, measured from the frost line to the lowest level at which grout was placed. It includes furnishing materials, labor, and equiipment for placing and mixing the grout.

Well Screen linear foot. Well Screens of slotted casing.

Measurement shall be from the bottom of the slotted casing to its connection with the well casing. Payment shall include all materials and labor for installation, and joining slotted casing sections.

Well Alignment Payment for this item is made and Plumbness under Article 3a.

Well Development hour of pumping. Payment shall include all materials, equipment, and labor necessary to complete the testing, measurement of static/pumping water drawdown/recovery data. Testing for performance is not expected to exceed five hours.

Testing for

Performance hour of pumping. Payment shall include all materials, equipment, and labor necessary to complete the testing, measurement of static/pumping water drawdown/recovery data. Testing for performance is not expected to exceed five hours.

Well Disinfection Payment for this item is made under Article 3a.

11a Well Abandonment linear foot of abadonded hole. Payment shall include materials, labor, and equipment for abandonment of a newly drilled well.

APPENDIX B

WELL LOG & PUMP INSTALLATION RECORD

PERMIT NUMBER

I. DESCRIPTION:

OWNER:

CONTRACTOR: (NAME, ADDRESS, PHONE)

USDA FOREST SERVICE

P.O. BOX 25127

LAKEWOOD, CO. 80225-0127

LICENSE NUMBER:

PROJECT:

FOREST:

DISTRICT:

STATE:

COUNTY:

________ 1/4, ________ 1/4, SEC. T. R.

DRILLING METHOD:

DRILLING STARTED: __________________ WELL COMPLETED: ___________________

(MO., DAY, YEAR)

(MO., DAY, YEAR)

GROUND ELEV. FT. CASING ELEV. FT.

ORIGIN FOR VERTICAL MEASUREMENTS:

__ NATURAL GROUND __ WELL CASING __ OTHER (SPECIFY): ___________________________

II. WELL CASING RECORD:

SIZE MATERIAL

INTERVAL:

WALL THICKNESS (IN)

FROM FT. TO _________

SCHEDULE/SDR

SCHEDULE/SDR

SCHEDULE/SDR _____________________________________________________________________________________

III. WELL SCREEN RECORD:

SLOT SIZE

FROM FT. TO

OPEN AREA

(SQ.IN/FT)

SLOT SIZE

FROM FT. TO

OPEN AREA

(SQ.IN/FT)

IV. ARTIFICIAL FILTER/BACKFILL/GROUT RECORD:

ARTIFICIAL FILTER:

SIZE OF GRAVEL _________________

FROM________ FT. TO ______________

BACKFILL:

FROM__________ FT. TO_________ FT.

FROM________ FT. TO ______________

GROUT:

WATER CEMENT RATIO: ___________

SAND/CEMENT RATIO

CEMENT CONTENT (NO. 94# BAGS CEMENT/CU. YD. GROUT

ADMIXTURES (SPECIFY):

FROM__________ FT. TO_________ FT.

FROM________ FT. TO ______________

V. DEVELOPMENT RECORD:

METHOD:

DEVELOPMENT AIDS (SPECIFY):

DURATION: ______ (HRS.), CUBIC FEET OF SAND REMOVED:

SAND CONTENT @ COMPLETION OF DEVELOPMENT (ML)

VI. PERFORMANCE TEST RECORD:

METHOD: DATE

STATIC WATER LEVEL BEFORE TEST FT.

DRAWDOWN:

RECOVERY:

_____FT. @_____ GPM AFTER _____HRS.

FT. AFTER HRS.

_____FT. @_____ GPM AFTER _____HRS.

FT. AFTER HRS.

_____FT. @_____ GPM AFTER _____HRS.

FT. AFTER HRS.

VII. WATER QUALITY RECORD:

FIELD SAMPLE/ANALYSIS:

PH

METHOD:

TEMPERATURE: DEGREES F

METHOD:

OTHER (SPECIFY):

LABORATORY SAMPLE/ANALYSIS:

COMPLETED: ___ NO ___ YES - ATTACH COPY OF ANALSIS

VIII. WELLHEAD CONSTRUCTION RECORD:

GROUND SURFACE:

___ GRADED TO DRAIN AWAY FROM CASING.

___ CONCRETE SLAB: (LxWxT)

___ OTHER (SPECIFY):

CAPPED: (TYPE, MANUFACTURER, SIZE, MODEL NUMBER, ETC.)

PITLESS UNIT:

PITLESS ADAPTOR:

(TYPE, MODEL NO., MANUFACTURER)

(TYPE, MODEL NO. MANUFACTURER)

BURY DEPTH FT.

BURY DEPTH: FT.

CASING DIA. IN.

CASING DIA.: IN.

DROP PIPE DIA. IN.

DROP PIPE DIA: . IN.

SUPPLY PIPE DIA. &

SUPPLY PIPE DIA. &

EXTENSION: _____IN. X _____FT.

EXTENSION: _____IN. X ______ FT.

OTHER (SPECIFY):

IX. PUMP INSTALLATION RECORD:

PUMP MAKE:

TYPE:

PUMP S/N: __________ MOTOR S/N: __________ ENGINE S/N: __________

PUMP INTAKE DEPTH: FT.

DATE INSTALLED:

POWERED BY: HP:

|INSTALLATION CONTRACTOR):

LICENSE NUMBER:

APPENDIX B1

DAILY DRILLING RECORD

PROJECT:

FOREST:

DATE:

TIME STARTED: (AM) (PM)

TIME ENDED: (AM) (PM)

WORK PROGRESS RECORD: (BRIEFLY DESCRIBE ALL WORK DONE, INCLUDING FEET DRILLED, MATERIAL TYPES, FORMATIONS ENCOUNTERED, WATER LEVELS AT START AND END OF EACH DAY, FEET OF CASING INSTALLED, WORK/CHANGE ORDERS ISSUED, PUMPING RATES, SHUT DOWN, AND ANY OTHER INFORMATION REQUIRED BY THE GOVERNMENT).

CONTRACTOR'S SIGNATURE:

LICENSE NUMBER:

DRILL HOLE RECORD:

PUMPING TEST DATA SHEET APPENDIX D

CONTINUOUS PUMPING RATE: GPM

DATE TEST STARTED: _____________

DATE TEST ENDED: ____________

MO. DAY YR.

MO. DAY YR.

PROJECT:

FOREST:

WELL LOCATION: 1/4, 1/4, SEC , T , R

TEST CONDUCTED BY:

ELEV. TOP OF CASING ABOVE GROUND: (FT.) GROUND ELEV.

STATIC WATER LEVEL FROM TOP OF CASING FT.

DEPTH TO PUMP FROM TOP OF CASING: FT.

DESCRIPTION OF PUMP:

METHOD OF MEASURING PUMPING WATER LEVEL:

APPENDIX DI ATTACHED: YES NO

APPENDIX DII ATTACHED YES NO

DRAWDOWN RECOVERY

CLOCK TIME

(hrs-min)

PUMPING TEST DATA SHEET (continuation sheet)

PROJECT:

DRAWDOWN RECOVERY

CLOCK TIME

(hrs-min)

TABLE 3.1

Steel Water Well Casing/Liner

NOMINAL

DIAMETERS

WALL

WEIGHT IN POUNDS

SIZE IN

IN INCHES

THICKNESS

PER FOOT

INCHES

EXTERNAL

INTERNAL

INCHES

PLAIN THREADS AND

ENDS OR COLLARS

2.375

2.067 0.154 3.56 3.71

2 1/2 2.875 2.469 0.203 5.79 5.88

3.500 3.068 0.216 7.58 7.67

3 1/2 4.000 3.548 0.226 9.11 9.27

4.500 4.026 0.237 10.79 11.01

5.563 5.047 0.258 14.62 14.90

6.625 6.065 0.250 18.97 19.33

8.625 8.071 0.250 24.70 25.44

10.750 10.192 0.250 31.20 32.20

12.750 12.090 0.375 43.77 45.40

14.000 13.250 0.375 54.57 55.80

16.000 15.250 0.375 62.58 64.08

18.000 17.250 0.375 70.59 72.37

20.000 19.250 0.375 78.60 80.70

The minimum wall thickness shown, for a given casing, is acceptable, i.e., for an 8-inch casing, a wall thickness of 0.250 inches is acceptable although for the convenience of the CONTRACTOR, a heavier wall may be used.

TABLE 3.2

PVC Water Well Casing/Liner

(160 psi)

(200 psi) (250 psi)

(315 psi)

NOMINAL

SDR26

SDR21 SDR17

SDR13.5

PIPE SIZE

MIN TOLERANCE

MIN TOLERANCE MIN TOLERANCE MIN TOLERANCE

| 0.176 +0.021

2 1/2

| 0.213 +0.026

| 0.259 +0.031

3 1/2 | 0.235 +0.028

0.296 +0.036

4 ....... ....... | 0.265 +0.032 0.333 +0.040

0.265 +0.032 0.327 +0.039 | 0.412 +0.049

a. ....... |

0.316 +0.038 b. 0.390 +0.047 | 0.491 +0.058

0.332 +0.040

0.410 +0.049 0.508 +0.061

0.413 +0.050

0.511 +0.061 0.632 +0.076

0.490 +0.059

0.606 +0.073 0.750 +0.090

a. Wall thickness below the line exceeds Schedule 40.

b. Wall thickness below the line exceeds Schedule 80.

The minimum wall thickness shown, for a given size of casing, is acceptable, e.g., for an 8-inch casing, a wall thickness of 0.332 inches is acceptable although for the convenience of the CONTRACTOR a heavier wall may be used.

TABLE 10.0 CHLORINE COMPOUND REQUIRED TO DOSE 100 FEET

OF WATER-FILLED WELL AT 100 PPM

CHLORINE COMPOUNDS

CASING

VOLUME

70% HTH

25% CHLORIDE

5.25% PUREX

DIAMETER

100 FT

PERCHLORON, ETC

OF LIME

CLOROX, ETC.,

(INCHES)

(GALS)

(DRY WEIGHT)*

(DRY WEIGHT)*

(LIQUID MEASURE)

16.3

1/2 OZ

1 OZ

4 OZ

65.3

2 OZ

4 OZ

18 OZ

146.9

4 OZ

8 OZ

40 OZ

261.1

6 OZ

14 OZ

4 1/4 PTS

408.0

8 OZ

22 OZ

7 PTS

587.5

12 OZ

2 LBS

10 PTS

1,044.5

20 OZ

3 1/2 LBS

2 GALS

1,632.0

2 LBS

6 LBS

3 1/2 GAL

2,350.1

3 LBS

8 LBS

4 2/3 GAL

NOTE: LIQUID SODIUM HYPOCHLORITE IN A 12 PERCENT SOLUTION IS OFTEN SOLD FOR WATER AND WASTEWATER TREAT-

MENT PLANT USE, AS A COMMERCIAL BLEACH, OR FOR USE IN SWIMMING POOLS. UTILIZING A SOLUTION OF THIS

NATURE WOULD CALL FOR A LIQUID MEASURE EQUAL TO ONE-HALF THE VOLUMES PRESENTED IN COLUMN 5.

* WHERE A DRY CHEMICAL IS USED, IT SHOULD BE MIXED WITH WATER TO FORM A CHLORINE SOLUTION PRIOR TO

PLACING IT INTO THE WELL. THIS APPLIES TO ALL WELLS EXCEPT FLOWING ARTESIAN WELLS

ITEM 11b WELL ABANDONMENT

GENERAL

1.01 Scope – Applies to the abandonment of the well at the existing Hunter Trailhead.

1.02 Applicable specifications

A. Concrete – FP-03 Standard Specification 601

PRODUCTS

2.01 Concrete – Concrete will meet the requirements of FP-03 Standard Specification 601 and State requirements.

EXECUTION

3.01 Disinfection – Disinfection shall be accomplished by dissolving sufficient chlorine compound to produce a calculated concentration of at least 100 ppm available chlorine in double the volume of water in the well. The fill material shall be placed in the well after the water in the well has been so treated (cement, cement-and-sand, and concrete do not require disinfection).

3.02 Permanent Bridges – Permanent bridges may be used to avoid having to fill very deep holes below the deepest point at which a permanent seal is required. Permanent bridges shall be composed only of concrete, cement, or sand-cement grout. The seal shall be allowed to harden for at least 24 hours, if Type I cement is used, or for at least 12 hours if Type III (high early strength) cement is used, before backfilling is continued. Temporary bridges used to provide a base for the permanent bridge shall consist only of clean inorganic materials-except that patented devices containing expandable neoprene, plastic, or other elastomers specifically designed for use in well construction, are acceptable.

3.03 Installation of Seal at Uppermost Aquifer – Cement, sandcement, or concrete seal shall be installed in the least permeable zone immediately above the uppermost water-producing zone. The minimum seal length, when dimension permit, shall be ten feet.

3.04 Installation of Intermediate Seals – Intermediate seals of cement, sand-cement ground, or concrete shall be placed in impermeable formations between aquifers which are identifiable as, or are suspected of being, hydraulically separated under natural, undisturbed conditions. Once the required seals have been installed, the remainder of the impermeable zone of non-producing zone between aquifers shall be filled with fill material. The minimum length of seal above the highest aquifer, when dimensions permit, shall be ten feet.

11b-1

3.05 Installation of Continuous Seal – Concrete, sand-cement grout, or cement shall be placed at the bottom of the well or interval to be sealed (or filled) and placed progressively upward to within five feet of the natural ground. All such sealing materials shall be placed by the use of grout pipe, tremie, cement bucket, or dump bailer, in such a way as to avoid segregation or dilution of the sealing materials. Dumping ground material from the top shall not be permitted.

Seals intended to prevent vertical movement of water in the well or bore hole shall be composed of cement, sand-cement grout, or concrete-except that where such seals must be placed within casing or liners, only neat sand-cement grout may be used. The cement water ratio shall not exceed 0.53. Seals shall be placed by means of pumping through drop pipe or by use of a dump-bailer, with placement beginning at the bottom and continuing upward. The minimum seal length, whenever dimensions permit, shall be ten feet.

3.06 Installation of Fill – Non-Producing Zone – Non-producing zones shall be filled with stable materials such as sand-and –gravel, cement, cement-sand, or concrete.