Attachment_A_Statement_of_Work_IDIQ.pdf

140G0122Q0082 Attachment A Statement of Work

IDIQ STATEMENT OF WORK

USGS CARIBBEAN-FLORIDA WATER SCIENCE CENTER

DRILLING AND INSTALLATION OF MONITORING WELLS IN PUERTO RICO

1.0 SCOPE AND LOCATIONS

1.01 The USGS Caribbean-Florida Water Science Center (USGS-CFWSC) is requesting bids for the drilling and installation of wells in support of a research project in the South Coast Aquifer in Puerto Rico. The drilling sites will be near the city of Salinas. Because the number of wells, location of wells, and time to secure permits are uncertain, an Indefinite-Delivery Indefinite-Quantity contract will be used to obtain the services. Each job will involve a Task Order with specific work involving the drilling services described in Section 15.

1.02 The proposed well sites are located near the city of Salinas in Puerto Rico. The specific locations are to be determined by the USGS-CFWSC Site locations may change given what is found as each well is installed.

1.03 The final depth of the wells may be anywhere between 50 and 600 ft depending on the geologic and hydrogeologic conditions encountered at the sites.

1.04 The work to be performed under this contract shall in general include the furnishing of all labor, material, equipment, supplies, and incidentals necessary for the installation of each monitoring well.

1.05 The work shall include, but not be limited to the following:

A. Well drilling, split-spoon core sampling, installation of casing and well screen, filter pack, grouting, well development, etc.

B. Clean-up and site restoration.

C. All other work as called for herein and/or shown on the plans.

D. Geophysical logging of the boreholes is desirable but the capability to perform geophysical logging is not required to place a bid.

1.06 Time is of the essence. The Contractor shall be prepared and willing to commence work immediately after notification of acceptance of proposal and shall complete all work in the shortest amount of time practicable.

1.07 The USGS shall issue Task Orders to the Contractor outlining the locations and job descriptions of work to be performed.

1.08 Each Task Order may order one or more wells to be drilled.

1.09 The USGS intends to issue two or more primary Task Orders, the first funding approximately 4 wells to be drilled in as fast a timeframe possible given site-specific conditions. Additional task orders may be issued depending on funds available and wells remaining. During performance, it is estimated that each well will take about 1 to 2 months from start to completion, depending on weather and well complexity. This statement of work is provided for information only and is not a guarantee of the scope and funding of Task Orders that will be issued.

2.0 SPECIAL CONDITIONS

2.01 Drilling capabilities of the Contractor’s equipment for the mud rotary method shall be up to 600 feet. Further, the contractor shall be able to address the USGS’s needs in an expeditious fashion by having immediate availability of all operational equipment necessary to conduct the specified work.

2.02 Site restoration must be completed within 30 days of well completion.

2.03 The Contractor shall not drill or perform any work which creates noise or requires bright lights that can be seen from other properties other than between the hours of 8:00 A.M. and 6:00 P.M., Monday through Friday. Weekend work is to be avoided. Exceptions will be allowed on a site-by-site basis based upon the depth and technical difficulties encountered. Efforts will be made to locate wells in municipal/park properties where more flexible hours may be allowed. Local municipal codes and landowner conditions must be observed.

2.04 The Contractor shall keep the site free of debris and shall remove all waste from the site weekly. The entrance way to the drilling sites shall be kept free of rubbish, dirt and other material.

2.05 The Contractor shall ensure public safety and site safety by providing security at the site while drillers are not present and by restricting access to the site throughout the operation.

3.0 RESPONSIBILITY

3.01 All responsibility for the entire work and accidents occurring therewith shall rest with the Contractor performing the Work until its completion and acceptance.

3.02 The Contractor shall comply with the U.S. Department of Labor Safety and Health Regulations promulgated under the Occupational Safety and Health Act of 1970 (PL 91 596) as currently amended; and under Section 107 of the Contract Work Hours and Safety Standards Act (PL 91 54), as currently amended, as a minimum requirement. In the event of conflict among said Safety and Health Regulations, the Contract Document and requirements of other regulatory agencies, the most stringent provisions shall be binding on the Contractor.

3.03 The Contractor is advised of the provisions of Section 4(b)(4) of the Occupational Safety and Health Act of 1970, which states: "Nothing in this Act shall be construed to supersede or in any manner affect any workman's compensation law to enlarge or diminish or affect in any manner the common law or statutory rights, duties, or liabilities of employers and employees under any law with respect to injuries, diseases, or death or employees arising out of, or in the course of, employment."

3.04 In order to protect the lives and health of his employees under this Contract, the Contractor shall comply with all pertinent provisions of the "Manual of Accident Prevention in Construction", issued by the Associated General Contractors of America, Inc., and shall maintain an accurate record of all cases of death, occupational disease, and injury requiring medical attention, or causing loss of time from work, arising out of and in the course of employment on work under the Contract. Contractor alone shall be responsible for the safety, efficiency and adequacy of his plant, appliances, and methods, and for any damage, which may result from their failure or improper construction, maintenance, or operation.

3.05 The selection of levels of personnel protective equipment is an iterative process based upon site specific conditions and available data. When no respiratory or dermal hazards exist, the Contractor shall proceed with a minimally protective work uniform consisting of coveralls, reinforced work boots and hard hats. Should the necessity for additional personnel protective equipment arise at Levels C or D, the Contractor shall proceed accordingly and be prepared to supply such additional protection for Contractor’s employees. USGS does not anticipate encountering contaminant plumes warranting the use of PPE higher than level D. OSHA requirements are not waived. Should such a situation arise where level C PPE or higher are required, the driller is to abandon the hole and notify the Contracting Officer’s Representative and the appropriate regulatory agencies. If a well or borehole needs to be abandoned due to no fault of the contractor, all work up to and including the abandonment will be paid to the contractor.

3.06 The USGS-CFWSC will not assume any responsibility whatsoever for loss or damage of equipment owned or operated by the Contractor, his agents, or employees or subcontractor or for the injury to or death of the Contractor, or his agents or employees, or his subcontractor. The Contractor will hold and save the USGS-CFWSC, its officers, agents, servants and employees harmless from liability of any nature or kind for or on account of the use of any copyrighted or uncopyrighted composition, secret process, patented or unpatented invention, articles or appliances, used in the performance of this Contract, including their use by the USGS-CFWSC unless otherwise specifically stipulated in the Contract. The Contractor will be responsible for any negligent or wrongful acts or omissions of the Contractor, his employees, agents or subcontractors and employees or agents of the subcontractor(s) incident to the performance of this Contract. The Contractor will hold and save the USGS-CFWSC, its officers, and employees harmless from all liability for any death or damage to persons or to real or personal property, including negligent use of materials used in conjunction with, or incident to, equipment furnished by the Contractor, or otherwise incident to performance of the Contract. The Contractor will not be responsible for any negligent or wrongful acts or omissions of the USGS-CFWSC, its employees, cooperators, or their employees.

3.07 The omission of the phrase "the Contractor shall" from these detailed Specifications shall not be construed as relieving the Contractor from full and complete performance of the work.

4.0 APPLICABLE CODES AND REGULATIONS

4.01 All work performed by the Contractor shall be in accordance with Federal, Commonwealth, State, County and Local Codes and Ordinances

5.0 STANDARD SPECIFICATIONS

5.01 Where reference is made in these Specifications to the Specifications of the American Society for Testing Materials (ASTM), the American Water Works Association (AWWA) or other societies, the portion referred to shall be read into and shall be a part of this Contract and these Specifications. Materials, methods and equipment, not particularly specified, shall conform to the latest local, state, commonwealth, and federal code requirements as they may relate to or govern the work.

6.0 PERMITS AND LICENSES

6.01 The Contractor shall be licensed by the commonwealth of Puerto Rico and shall comply with all regulations and requirements of the Department.

6.02 The Contractor shall procure all licenses or other permits, if any, and pay all taxes, fees, charges and give notices necessary and incident to the lawful prosecution of the work. Every effort will be made to place wells in either right-of-way or municipal properties and/or county/city parks. Costs related to permits will be reimbursable to the contractor as provided in the Unit Price Sheet.

7.0 MATERIALS AND WORKMANSHIP

7.01 All materials and workmanship shall be of the best quality and shall be subject to the approval of the USGS-CFWSC. No deviations from the provisions of these detailed Specifications herein shall be made without written approval of the USGS-CFWSC.

7.02 Only first-class work shall be performed, and all materials furnished in carrying out this Contract shall be of character and quality required by these Specifications. Where no standard is specified for such work or materials, they shall be the best of their respective kinds. Any unsatisfactory work done or materials furnished at whatever time they may be discovered shall be immediately removed and satisfactorily replaced by the Contractor when notified to do so by the site hydrologist. Upon the completion of each Task Order, the entire work shall be delivered to the USGS CFWSC in satisfactory working condition.

8.0 STORAGE OF MATERIALS

8.01 Materials shall be stored as to insure the preservation of their quality and fitness for the work. When considered necessary, they shall be placed on wooden platforms or other hard clean surfaces and not on the ground and shall be placed as to facilitate proper inspection. Other private property shall not be used for storage purposes without the written permission of the USGS-CFWSC. The USGS will work with the contractor to arrange with municipalities to provide potential staging areas on a case-by-case basis. No guarantees are made of staging area availability. If no staging areas can be secured the contractor will charge a unit price for mobilization and demobilization of equipment.

9.0 PROTECTION OF EXISTING WORKS

9.01 All existing structures, piping, utilities, fencing or materials, “herein refer to as properties”, within each site area shall be protected against damage as may be required by the USGS-CFWSC. The Contractor shall be responsible for any damage cause by the contractor’s error, accident, or negligence.

10.0 REFERENCE ITEMS

10.01 It should be noted that the Addenda or Specifications for certain contract items contained herein refer directly or indirectly to the specifications for other items for standards of workmanship, methods, equipment, quality of materials, etc. even though the items referred to are not included in the proposal. No additional payment will be made by reason of such reference. The cost of the work, materials, equipment, or procedures referred to shall be included in the unit price bid in the proposal.

11.0 NECESSARY DETAILS NOT SPECIFICALLY MENTIONED

11.01 Any work or material related to the drilling and installation of observation wells which is not denoted in these Specifications either directly or indirectly, but which is, nevertheless, necessary for the proper carrying out of the intent thereof, it is understood and agreed that the same is implied and required and that the Contractor shall perform such work and furnish such materials as fully as if they were completely delineated and described.

12.0 UNFORSEEN OBSTACLES

12.01 Any geologic materials such as hardpan and boulders encountered during drilling, shall be demolished and disposed of by the Contractor. USGS intends to select drilling locations where drilling speed and efficiency is maximized. However, there is no guarantee that boulders will not be encountered in the subsurface and in some extreme cases moving the drill rig and restarting the borehole may be required. The nature of drilling in Puerto Rico is dealing with variable subsurface geology which could include boulders, hardpan, and other materials.

13.0 LOCAL CONDITIONS

13.01 Where possible, the wells shall be drilled on a section of land located on the right-of-way property near each proposed well location. The USGS-CFWSC will designate the general location where work will be performed. After the general location has been established, the Contractor shall call for a mark out of all utilities, i.e. electric, gas, water, sanitary sewer, drainage, telephone, irrigation, street lighting, tunnels (rail or auto) or any other suspected underground appurtenances within the area. Upon mark out completion of all utilities, the Contractor with the concurrence of the USGS-CFWSC shall determine the actual drilling site, which allows for safe drilling and does not interfere with any underground utilities and appurtenances.

13.02 The Contractor shall be responsible for ensuring a freshwater supply with a chloride concentration not exceeding 100 mg/L is available. If an adequate freshwater supply is not available locally near the drilling sites, the Contractor shall truck in water that meets this specification.

13.04 If there is no available electrical power at a site the Contractor shall provide his own source of power.

13.05 U.S. Geological Survey publications and existing well logs are the only source of data available on the geology at the proposed well locations.

13.06 It is anticipated that security will be required for the drilling sites.

14.0 WELL DRILLING

15.01 The Contractor shall use the mud rotary method to drill boreholes for the purpose of installing a 4-inch monitoring well in the borehole at each site. Each mud rotary borehole will be drilled to bedrock and an additional 10 to 20 feet when possible. The final depths will depend on the depth at which bedrock is encountered during drilling.

14.02 The contractor will use Bentonite Drilling Fluid, as distributed by Johnson Screens, Inc., or equal, when drilling by the rotary method. No drilling fluid additives that could create an environmental hazard, no iron fillings, and no iron-based additives are to be used. The driller will monitor and maintain the drilling fluid integrity when encountering saltwater intruded aquifers.

14.03 The Contractor shall use a portable mud pit when using the mud rotary method.

14.04 The Contractor shall provide all labor, tools, personnel, and materials required to perform and complete the drilling in a safe and efficient manner. All cuttings will be properly removed from the site by the Contractor. In the event that the Contractor's equipment is judged unsatisfactory, the Contractor will be expected to replace the unsatisfactory equipment with equipment which is acceptable to the USGS-CFWSC, and within sufficient time to complete the Contract on schedule.

14.05 It is expected that the wells will be drilled into unconsolidated deposits of gravel, sand, silt and clay and weathered bedrock. Geological conditions at the proposed well sites are not guaranteed by the USGS-CFWSC.

14.06 The Contractor shall take every precaution and measure to ensure that the wells are drilled true and plumb. Plumbness of the wells shall be checked frequently during the drilling process. Significantly deviated boreholes are unacceptable.

14.07 The Contractor shall drill the wells with a modified roller cone bit (with an opening on the end) to allow split spoon sampling during drilling and the ability to drill about 20 feet into weathered bedrock.

14.08 During the drilling operations, test cores shall be taken with a split spoon core sampler, which shall be driven vertically into undisturbed formation material in the bottom of each drilled hole. Each core shall be at least 12 inches in continuous length.

Test cores shall be taken every 20 feet from land surface to the bottom of the drilled well. Smaller intervals if requested at the base of the deepest aquifer to be determined by the USGS-CFWSC.

15.0 GEOPHYSICAL LOGGING

15.01 Performing the following geophysical logging in the open borehole is desirable.

However, having the ability to perform the geophysical logging is not required to place a bid.

A. Gamma-Ray Logging

B. Electric Logging

C. Caliper Logging

16.0 WELL CASING AND SCREEN INSTALLATION

16.01 Well casing and screen installation shall be in accordance with ASTM D5092 and as indicated on the generalized well drawing. The Contractor shall consult with and obtain concurrence with the USGS-CFWSC representative to determine the specific well details for each site.

16.02 Casing shall be 4-inch-diameter, flush threaded, casing with o-ring seals in schedule 80 or schedule 120 polyvinyl chloride (PVC), depending on the depth of the well. The contractor shall be responsible for ensuring that the strength properties of the casing are adequate for conditions in borehole.

16.03 A 5-foot long, 4-inch diameter, open-ended 0.010-inch slot size, Schedule 80 or 120 PVC well screen will be installed at the base of the aquifer.

16.04 Well centralizers can be used to keep the casing straight and plumb, however no metal can be used for, or to attach these centralizers. Even small metal screws can greatly interfere with the electromagnetic logs and cannot be used.

16.05 The final casing must be watertight and free of leaks or the well must be replaced free of additional charge.

16.06 The Contractor shall provide all casing together with required O-rings and pipe sealant/cement, couplings, plugs, caps, fittings, or other parts necessary to satisfactorily complete the casing installation. Casing and screen shall be installed sufficiently plumb to allow installation or tremie pipes for proper grouting of the casing and operation of all sampling equipment. No metal shall be used anywhere in well installation. This includes metal screws, clamps, screens, or spacers.

16.07 All PVC screens and casing sections shall be cleaned and bagged prior to delivery.

16.08 In most cases there will be significant lengths of PVC casing set below the screen depth (a sump) to allow geophysical logging below the base of the deep aquifer and into the weathered bedrock whenever and wherever possible. The final depths of wells will be provided to the Contractor by the USGS-CFWSC on a site-by-site basis based upon conditions found at each site and the hydrogeologic information from cores and borehole geophysical logs collected.

16.09 The Contractor shall provide all well screens and fittings and other materials necessary for a complete installation.

16.10 The contractor will develop each well until the water is clear and free of suspended sediment and drilling fluids and is pumping at an acceptable discharge rate.

16.11 The contractor will ensure the pipe joints are free from any leakages of water into or from the surrounding formations through use of the required PVC casing (see section 16.02) and limiting deviation to within specifications. If leaks are detected after well pumping, sampling, and or cased geophysical logging, the contractor will backfill and properly abandon the well at no charge to the USGS and replace the well at no charge to the USGS.

16.12 Other than a metal protective housing at the surface, there must be no metal used in the installation of the well. There must be no bends or constrictions that prevent geophysical probes from going down the well, and there must be no metal debris down the well.

17.0 ANNULAR SPACE BACKFILL MATERIAL

17.01 All materials installed to fill the annular space shall be installed using a tremie pipe rather than just poured into the annular space from the surface with the hope that they will sink to the bottom and not bridge at some shallower depth.

17.02 Frequent measurements must be made to ensure that all materials are installed at the proper depths. Bridged materials are unacceptable. There must be no gaps caused by bridging in the annular seal.

17.03 The depths of all layers of materials shall be measured and these depths shall be recorded in a log to verify that they have been properly emplaced.

17.04 Annular space below the well screen - The annular space below the well screen shall be grouted with bentonite grout, a grout consisting of cement and bentonite, bentonite pellets, or a combination of these materials (Section 19). This grout layer shall extend from about 5 feet below the screen to the full well depth. Extreme care and frequent measurements are needed to ensure that this grout does not reach the screen.

As a precaution this back-filling can be stopped 5 feet below the screen, and a fine sand emplaced for a couple feet. The filter pack (Section 17.05) can extend to 3 feet below the screen.

17.05 Filter pack - The Contractor shall furnish and place clean 20/40 silica sand in the annular space between the hole and the well screen, in the depth interval extending from a few feet below, to a few feet above screen. The material shall be placed at the direction of the USGS CFWSC representative at the depth and thickness between the well casing and outer wall of the annular space. The particle size of the filter pack shall be designed to keep fines in the aquifer from plugging the well. Work under this item shall include but not be limited to:

A. Placement of filter pack sand at designated depths.

B. Removal of obstacles restricting placement along the well casing.

C. Install filter pack using a tremie pipe - do not just pour filter pack into annular space from surface and hope it settles to the bottom without bridging.

D. Frequently measure the depth of the filter pack to make sure that it extends at least 2 feet above the top of the screen.

17.06 Fine sand layer above the filter pack – 2 to 4 foot layer of fine sand is installed above the filter pack to prevent any grout or bentonite from leaking down into the filter pack.

17.07 Bentonite pellet layer – At a minimum, a 2- to 4-ft (~0.9- to ~1.5-m) bentonite pellet seal overlying the filter pack is required to ensure proper well completion. This layer must be bentonite pellets rather than chips. Bentonite chips may hydrate too rapidly and cause clogging of the tremie pipe or bridging.

17.08 The materials of the annular seal in the saturated zone shall be designed to consider differences in the permeability of the strata of the aquifer. Where highly porous strata occur, the annular space shall be filled with sand or pea gravel, and where relatively impermeable strata occur, the annular space shall be sealed with bentonite grout (Section 19). This will allow any saltwater flowing through the aquifer to get near enough to the well so that it can be detected by the induction logs.

17.04. Annular seal in the unsaturated zone - The unsaturated part of the aquifer will be filled with neat cement grout (Section 19) to prevent drying out and cracking of the annular seal. Cement grout will be installed in lifts of no greater than 20 feet in a day to prevent overheating during curing which might warp or cause bends in the casing.

18.0 SURFACE COMPLETION

18.01 A vent hole shall be drilled in the casing near the surface, and a locking, watertight well plug (i.e. a locking nylon expansion plug or a water tight hinged locking cap) must be installed.

18.02 The well must be enclosed in a metal watertight monitoring well manhole 8 to 12 cover with bolt down lid and gasket to prevent tampering.

18.03 A 3-foot diameter, approximately 1 foot thick, cement well pad shall be installed around the protective casing.

18.04 The protective casing, well pad, and upper most part of the annular seal shall be designed to make sure the protective casing will drain and not hold water.

19.0 CEMENT/BENTONITE GROUT

19.01 The Contractor shall install bentonite grout, cement, or a mix of cement and bentonite in the annular space between the borehole wall and the well casing. The cement will only be used in the unsaturated zone where bentonite grout might dry out and crack. The mix of bentonite and cement is only used for backfilling the hole or around the tail pipe to provide strength to build the remainder of the well on. The bentonite grout is used to fill most of the annular spaces except the depth intervals where sand is used to simulate the porosity of surrounding geologic strata. All work shall be as directed by the USGS-CFWSC. Work shall include but not be limited to:

A. Opening a clear annular space by circulation of drilling fluids and removal of any obstruction.

B. Mixing and placement of the cement bentonite, cement, or bentonite slurry by tremie or pumping. The tremie pipe or any conduit shall extend from ground surface to the level within the annular space as specified by the USGS-CFWSC (generally this level will be within close proximity to the seal above the gravel pack material).

19.03 The cement slurry shall be a mixture of Portland cement, bentonite, and clean water. Potable water shall be used for cement grout. A Bentonite additive will be used.

The slurry must be placed by a continuous operation. The grout should be introduced at the base of the grouting interval to minimize contamination or dilution of the slurry and bridging of the mixture with upper-formation material. Slurry shall be pumped into place, not placed by gravity except when approved by the USGS CFWSC. Any sand used in slurry shall conform to NCDPW and H&GE Spec. M3B. Portland cement shall be Type II conforming to ASTM-C-150. Grout must be a mix of bentonite and cement so as to prevent melting of the PVC casing during curing. Grout to be installed from top of gravel pack to top of well via tremie pipe.

20.0 PLUMBNESS

20.01 The contractor shall make every effort to make each borehole as plumb as possible. Significantly deviated boreholes are unacceptable. The boreholes shall be sufficiently plumb to allow the successful installation and removal of geophysical logging equipment and the successful installation and functioning of a monitoring well. The monitoring wells shall be sufficiently plumb to allow the installation and removal of submersible well pumps and geophysical logging equipment.

21.0 SANITARY FACILITIES

21.01 The Contractor shall conduct all operations in a clean and sanitary manner. No nuisance shall be committed in the work area. The Contractor shall either use proper waste receptacles or leave the site whenever the necessity arises. Portable toilet facilities shall be provided and paid for by the contractor for the use of his personnel at the site. The facilities shall be maintained in a clean sanitary condition and shall remain on the site for the duration of the project.

22.0 TEMPORARY FENCE

22.01 The Contractor shall furnish and install temporary fence, including fabric, fence posts, etc. as directed by the USGS CFWSC for safety reasons.

22.02. The Contractor shall protect and maintain the existing temporary fence at the site until the drilling equipment is removed. The Contractor shall then remove and legally dispose of the temporary fence around the well site.

23.0 CLEARING AND TRIMMING

23.01. The Work shall include the preservation from injury or defacement of all vegetation and objects designated to remain. Although not guaranteed, USGS intends to select final drilling locations that do not require tree and shrub trimming or grubbing.

23.02 The USGS CFWSC will establish the limits of the Work and will designate all trees, plants, shrubs and other items to remain. The Contractor shall protect and preserve all items designated to remain.

23.03. Miscellaneous trimming of trees or shrubs designated to remain shall be conducted if required by the contractor. Trimming shall be in accordance with good tree surgery practice. Although not guaranteed, USGS intends to select final drilling locations that do not require tree and shrub trimming or grubbing.

23.04. All vegetation and debris to be removed shall be disposed of by the Contractor within areas indicated on the Drawings or areas approved by the USGS CFWSC. The Contractor shall obtain all required permits.

23.05. The Contractor is responsible for:

A. Securing waste disposal sites, B. Obtaining written permission of the owner of the disposal site, and C. Securing any required permits.

23.06. The cost of securing disposal sites shall be borne by the Contractor. If requested by the USGS CFWSC, the Contractor shall furnish the permit numbers of all required permits for disposal sites.

23.07. In areas where Hand Clearing is indicated on the Drawings or designated by the USGS CFWSC, no equipment on wheels or tracks shall be used. Care shall be taken to ensure that the grass, moss cover, or the natural ground is not disturbed. Stumps and very small trees shall be cut flush with the ground, except that in areas within four feet or more of embankment cover, stumps may be cut off 6 inches above the natural ground. Although not guaranteed, USGS intends to select final drilling locations that do not require tree and shrub trimming or grubbing.

24.0 TOPSOIL

24.01 The Contractor shall use suitable topsoil stockpiled by the Contractor from his work. Additional topsoil may be required from off site as determined by the USGS-

CFWSC.

24.02 All areas intended to be regraded are to be stripped of any remaining topsoil to whatever depth it may occur, except in places where grading involves a fill not more than 5 inches.

24.03 All topsoil is to be kept free from roots and stones, and that portion which cannot be used immediately upon regarded areas is to be piled in neat spoil banks located on the Site as directed by the USGS CFWSC.

24.04 In stripping topsoil, care is to be taken to avoid admixture of subsoil. If the amount of topsoil on the site is inadequate, the Contractor shall furnish sufficient additional topsoil. No topsoil which has been stripped shall be removed from the site.

24.05 Topsoil to be supplied to site shall consist of a fertile, friable, natural topsoil of loamy character from the “A” Horizon without a mixture of subsoil, uniform in quality and shall be free from refuse of any nature, hard clods, sods, hard pan, pebbles larger than ¾- inch diameter, coarse sand, noxious weeds, sticks, brush or other rubbish.

Topsoil shall have a pH of not less than 5 and not more than 7.

24.06 Source of Supply: All topsoil, both rehandled and/or supplied from outside sources, shall be accumulated, tested and approved by the USGS CFWSC prior to its inclusion in any work performed as part of this Contract. Additional testing of topsoil will be performed by the USGS CFWSC as necessary to ensure compliance with these specifications.

25.0 SPREADING TOPSOIL

25.01 Topsoil stored on the site from this project shall be spread over the disturbed areas. Additional topsoil may be required from off-site.

25.02 The surface of the areas to be covered with topsoil shall be graded to a depth of 4 inches below the finished grade of the topsoil. Before placing the topsoil, the prepared area shall be raked to insure proper bond. The soil shall be free from roots, stones over one inch in diameter and any material that will interfere with good cultivation. The topsoil shall spread to sufficient depth above proposed grades to allow for settlement, raked to remove stones and debris and lightly compacted. The minimum depth after settlement shall be 4 inches.

26.0 SEEDING

26.01 Seeding is to be done when directed by the USGS CFWSC representative.

26.02 No seeding shall be done until the topsoil has been hand raked to the required finished grades.

26.03 The topsoil shall be smooth, friable and of a uniformly fine texture. No seed shall be sown unless the top surfaces of the seed bed is free of stones larger than ½-inch, roots, weeds, sod or other litter.

26.04 The Contractor is responsible for ensuring that bags of seed comply with any agricultural seed laws in the local area or Puerto Rico.

26.05 All excess material shall be removed from the site including any unsuitable material.

26.06 All topsoil, seed, fertilizer, etc. shall be as approved by the USGS CFWSC representative.

27.0 SITE CLEANUP

27.01 After completion of the work, all tools, appliances, surplus materials, temporary drainage, rubbish and debris incidental to the work shall be removed from site within one week.

27.02 Backfill excavation and vehicular ruts shall be dressed to conform to the existing landscape or terrain.

27.03 Utilities, structures, roads, fences, or any other pre-existing item which must be repaired or replaced due to the Contractor’s negligence are the Contractor’s responsibility and must accomplish repair or replacement within 30 days of well completion.

27.04 The contractor will be responsible for the disposal of drill cuttings, rock core, grout or bentonite slurry, and other solid or liquid materials bailed, pump or otherwise removed from the borehole during drilling, well installation and completion procedures shall be disposed of within all appropriate regulatory requirements.

27.06 Site restoration must be completed within 30 days of well completion.

27.07 The drilling contractor shall ensure no obstructions exist from the surface to the bottom of the borehole upon completion of the well and if one is found to rectify it at their expense.