42-02310 Horizontal DD.pdf

SECTION 02310

HORIZONTAL DIRECTIONAL DRILLING HDPE PIPE DIVISION 2

West Branch Regional Authority 02310-1 January 2026 Route 54 Sanitary Sewer Extension Project Horizontal Directional Drilling HDPE Pipe Contract No. WB-1

PART 1 - GENERAL

1.01 DESCRIPTION OF WORK

A. Scope

1. The Contractor shall provide all work including, but not limited to all preliminary investigations, planning, geotechnical work, equipment, labor, etc., necessary to properly install the proposed directional bores, pipe and appurtenances as set forth on the Drawings and in accordance with this section of the Specifications.

B. Related Work Specified Elsewhere in Contract Documents

1. Trench excavation, bedding, backfill, and related pipe installation work are described in Section 02205: Earthwork for Pipelines

2. Section 02820: Topsoil, Seeding and Mulching

3. Appendix No. 1 - Standard Specifications for Extensions of and Connections to the West Branch Regional Authority Sanitary Sewer System, April 2014

4. Section 02300: High Density Polyethylene (HDPE) Pipe

5. Section 15070: Piping System Appurtenances

1.02 SAFETY CONSIDERATIONS

A. The Contractor shall comply with all applicable, local, State, and Federal safety laws, codes, and regulations.

B. The Contractor will assume full responsibility and liability for all property damage and bodily injury that may result from him damaging or disturbing any equipment, utilities, structures, powerlines, water, sewer and drain lines, or other facilities.

C. The Contractor's attention is directed to the fact that there are existing waterlines, telecommunications, electric, sewer pipes, storm sewers, underground storage tanks and other utilities within the Project area. An attempt has been made to indicate the location of these utilities on the Drawings, but the completeness or accuracy of the information provided is not guaranteed. Verification of utilities and their locations shall be the sole responsibility of the Contractor.

1.03 QUALITY ASSURANCE

A. The Contractor shall be experienced and actively engaged in Horizontal Directional Drilling

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(HDD) for a minimum of three (3) years.

B. The field supervisory personnel shall be experienced in the performance of the work and tasks as stated herein for a minimum of three (3) years.

C. Refer to the requirements in Section 01000: Summary of Work and Special Requirements.

1.04 SUBMITTALS

A. Refer to the requirements in Section 01340: Shop Drawings, Product Data and Samples.

B. Submit for information only.

1. Presentation of similar experience in the last three (3) years.

2. Include, but not limited to, Owner’s name, address, telephone number, contact person, date and duration of work, location, pipe information, and contents handled by pipeline.

3. Supervisory field personnel and historical information of HDD experience.

a. At least one (1) field supervisor listed must be at site when HDD operations are in progress.

C. Submit the following:

1. Detailed Installation Plan - Two (2) weeks prior to commencing with any drilling activity, submit working Drawings and written procedure describing in detail proposed method and entire operation for information only including, but not limited to:

a. Size, capacity and arrangement of equipment.

b. Location and size of drilling and receiving pits, access pits, relief pits and any pit required for fittings and water service connections/ recommendations.

c. Dewatering and methods of removing spoils material.

d. Method of installing detection wire and pipe.

e. Type, location and method of installing locator station.

f. Method of fusion pipe segment and type of equipment.

g. Type of cutting heads.

h. Method of monitoring and controlling line and grade.

i. Detection of surface movement.

j. Bentonite drilling mud for information only:

1) Products information, material specifications, and handling procedures.

2) Material safety data sheet and special precautions required.

3) Method of mixing and application.

West Branch Regional Authority 02310-3 January 2026

2. Municipality/PennDOT HOP Coordination - If the Contractor's proposed detailed investigation plan differs from what is shown on the Drawings in terms of drilling pit openings/locations, then prior approval from Municipality/PennDOT and Engineer of the plan will be required before commencement of work.

D. Close Out Submittals.

1. Section 01720: Project Record Documents: Record locations of pipe and invert elevations.

2. Identify and describe unexpected variations in subsoil conditions or discovery of uncharted utilities.

3. Record actual depth of pipe at 20 feet intervals.

4. Record actual horizontal location of installed pipe based on known established reference points (i.e. utility poles).

5. Shoe depth and location of abandoned bores.

6. Record depth and locations of drill bits and drill stems not removed from bore.

1.05 DELIVERY, STORAGE AND HANDLING

A. Section 01600: Materials and Equipment - Requirements for transporting, handling, storing and protecting products.

B. Provide temporary end caps and closures on piping and fittings until pipe is installed.

C. Protect pipe from entry of foreign materials and water by temporary covers, completing sections of work, and isolating parts of completed system.

D. Accept products on site in manufacturer's original containers or configuration. Inspect for damage.

E. Use shipping braces between layers of stacked pipe. Stack piping lengths no more than three layers high.

F. Store field joint materials indoors in dry area in original shipping containers. Maintain storage temperatures of 60 to 85 degrees F.

G. Support pipes with nylon slings during handling.

1.06 ENVIRONMENTAL CONDITIONS

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A. Conduct operations so as not to interfere with, interrupt, damage, destroy, or endanger integrity of surface or subsurface structures or utilities, and landscape in immediate or adjacent areas.

B. Comply with applicable ordinances, codes, statutory rules and regulations. Applicable regulations of Federal Government, OSHA 29 CFR 1926 and applicable criteria of ANSI A10.16, Safety Requirements for Tunnels shafts and caissons.

PART 2 - PRODUCTS

2.01 SCOPE

A. General:

It is the intent of this Specification to define the acceptable methods and materials for installing sanitary sewer and water mains by the horizontal directional drilling method and the requirements for high density polyethylene (HDPE) pipe installed by directional drilling or in open cut trenches.

B. Installation Plan:

1. At least two (2) weeks prior to commencing with any drilling activity, the Contractor shall submit his Detailed Installation Plan to the Engineer. The plan shall include a detailed plan and profile of the bores and be plotted at a scale no smaller than 1-inch equals 20 feet horizontal and vertical.

2. The plan shall also include all information requested under Paragraph 1.04.C.

C. Variations in Plan or Profile:

The Contractor may request changes to the proposed vertical and horizontal alignment of the installation and the location of the entry and exit points. Proposed changes shall be submitted in writing to the Engineer and receive approval of the Engineer prior to construction. Any deviation from the construction drawings with respect to alignment and bore pit locations will also require the approval of Municipality/PennDOT as the proposed waterline is being installed in Municipality/PennDOT right-of-way.

D. Alignment:

The proposed plan and profile installation locations are based on alignments to accommodate acquired easements, to avoid obstructions, and to properly maintain operation flow velocities.

E. Qualifications:

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Directional drilling and pipe installation shall be done only by an experienced Contractor specializing in directional drilling and whose key personnel have at least three (3) years’ experience in this work. Furthermore, the Contractor shall have installed directionally drilled pipe at least as large as six (6) inches in diameter and successfully installed at least 20,000 feet in length.

2.02 MATERIALS

High density polyethylene pipe in accordance with Section 02300: High Density Polyethylene (HDPE) Pipe in addition to these Specifications shall be used in HDD installations. All piping system components shall be the products of one manufacturer and shall conform to the latest edition of ASTM D1248, ASTM D3350 and ASTM F714.

B. Procedures:

1. General:

All polyethylene pipe shall be cut, fabricated, and installed in strict conformance with the pipe manufacturer's recommendations. Joining, laying, and pulling of polyethylene pipe shall be accomplished by personnel experienced in working with polyethylene pipe. The pipe supplier shall certify in writing that the Contractor is qualified to join, lay, and pull the pipe or representative of the pipe manufacturer shall be on site to oversee the pipe joining. Expense for the representative shall be paid for by the Contractor.

2. Transportation:

Care shall be taken during transportation of the pipe to ensure that it is not cut, kinked, or otherwise damaged.

3. Storage:

Pipes shall be stored on level ground, preferably turf or sand, free of sharp objects which could damage the pipe. Stacking of the polyethylene pipe shall be limited to a height that will not cause excessive deformation of the bottom layers of pipes under anticipated temperature condition. Where necessary due to ground conditions, the pipe shall be stored on wooden sleepers, paced suitably and of such widths as not to allow deformation of the pipe at the point of contact with the sleeper or between supports.

4. Handling Pipe:

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The handling of the joined pipeline shall be in such a manner that the pipe is not damaged by dragging it over sharp and cutting objects. Ropes, fabric, or rubber protected slings and straps shall be used when handling pipes. Chains, cables, or hooks inserted into the pipe ends shall not be used. Two slings spread apart shall be used for lifting each length of pipe. Pipe or fittings shall not be dropped onto rocky or unprepared ground. Slings for handling the pipeline shall not be positioned at butt-fused joints. Sections of the pipes with cuts and gouges exceeding 10 percent (10%) of the pipe wall thickness or kinked sections shall be removed and the ends rejoined.

The open ends of all sections of joined and/or installed pipe (not in service) shall be plugged at night to prevent animals or foreign material from entering the pipe line or pipe section.

Waterproof nightcaps of approved design may be used but they shall also be so constructed that will prevent the entrance of any type of natural precipitation into the pipe and will be fastened to the pipe in such a manner that the wind cannot blow them loose.

The practice of stuffing cloth or paper in the open ends of the pipe will be considered unacceptable.

Where possible, the pipe shall be raised and supported at a suitable distance back from the open end such that the open end will be below the level of the pipe at the point of support.

PART 3 - EXECUTION

3.01 INSTALLATION

1. The Contractor shall install the pipelines by means of horizontal directional drilling.

The Contractor shall assemble, support, and pretest the pipeline prior to installation in the directional drill tunnel.

2. Horizontal directional drilling shall consist of the drilling of a small diameter pilot hole from one end of the alignment to the other, alIowed by enlarging the whole diameter for the pipeline insertion. The exact method and techniques for completing the directionally drilled installation will be determined by the Contractor, subject to the requirements of these Specifications.

3. The Contractor shall prepare and submit a plan to the Engineer for approval for insertion of the HDPE pipe into the opened bore hole. This plan shall include

West Branch Regional Authority 02310-7 January 2026 pullback procedure, pulling tracer wire, ballasting, use of rollers, side booms and side rollers, coating protection, internal cleaning, internal gauging, hydrostatic tests, dewatering, and purging.

4. The required piping shall be assembled in a manner that does not obstruct adjacent roadways or public activities. The Contractor shall erect temporary fencing around the entry and exit pipe staging areas.

B. Joining Pipe Sections:

1. Each length of pipe shall be inspected and cleaned as necessary to be free of debris immediately prior to joining.

2. Pipes shall be joined to one another by means of thermal butt-fusion. Polyethylene pipe to be joined thermal butt-fusion shall be of the same type and class of polyethylene compound and supplied from the same raw material supplier.

3. Mechanical connections of the polyethylene pipe to auxiliary equipment shall be through flanged connections which shall consist of the following:

a. A polyethylene "sub end" shall be thermally butt-fused to the ends of the pipe.

b. Provide ASTM A240. Type 304 stainless steel backing flange, 125 pound, ANSI B16.1 standard, and gaskets as required by the manufacturer.

c. Stainless Steel bolts and nuts of sufficient length to show a minimum of three complete threads when the joint is made and tightened to the manufacturer's standard. Retorque the nuts after four (4) hours.

d. Butt-Fusion Joining: Butt-fusion of pipes shall be performed in accordance with the manufacturer's recommendations as to equipment and technique.

Butt-fusion joining shall be 100% efficient offering a joint weld strength equal to or greater than the tensile strength of the pipe.

C. Testing:

1. The pipe shall be hydrostatically tested after joining into continuous lengths after installation. Pressure and temperature shall be monitored with certified instruments during the test. After this test, the water will be removed with pigs.

Erosion prevention procedures will be used during removal and discharge of the water.

2. Hydrostatic testing shall be performed in accordance with Appendix No. 1. All costs associated with acquiring water for testing shall be included in the

West Branch Regional Authority 02310-8 January 2026 established contract unit bid prices.

D. Tolerances:

1. Pipe installed by the directional drilled method must be located in plan as shown on the Drawings and must be no shallower than shown on the Drawings unless otherwise approved. The Contractor shall plot the actual horizontal and vertical alignment of the pilot bore at intervals not exceeding 30 feet. This "as built” plan and profile shall be updated as the pilot bore is advanced. The Contractor shall at all times provide and maintain instrumentation that will accurately locate the pilot hole and measure drilling fluid flow and pressure. The Contractor shall grant the Engineer access to all data and readout pertaining to the position of the bore head and the fluid pressures and flows.

When requested, the Contractor shall provide explanations of this position monitoring and steering equipment. The Contractor shall employ experienced personnel to operate the directional drilling equipment and, in particular, the position monitoring and steering equipment. No information pertaining to the position or inclination of the pilot bores shall be withheld from the Engineer.

2. Each exit point shall be located as shown with an over-length tolerance of 10 feet for directional drills of 1,000 linear feet or less and 40 feet for directional drills of greater than 1,000 linear feet and an alignment tolerance of 5 feet left/right with due consideration of the position of the other exit points and the required permanent easement. For gravity sanitary sewer installations, sags in the pipeline shall not exceed 25 percent (25%) of the nominal pipe diameter. Sags will only be allowed where the entering and exiting grades are adequate to provide velocities through the sag area sufficient for moving solids. No more than one (1) sag area shall occur between two (2) manholes. The alignment of each pilot bore must be approved by the Engineer before pipe can be pulled. If the pilot bore fails to conform to the above tolerances, the Engineer may, at his option require a new pilot boring to be made.

3. After the pipe is in place, cleaning pigs shall be used to remove residual water and debris. After the cleaning operation, the Contractor shall provide and run a sizing pig to check for anomalies in the form of buckles, dents, excessive out-of-roundness, and any other deformations. The pig run shall be considered acceptable if the survey results indicate that there are no sharp anomalies (e.g.

dens, buckles, gouges, and internal greater than 2 percent (2%) of the nominal pipe diameter, or excessive ovality greater than 5 percent (5%) of the nominal pipe diameter. For gauging purposes, dent locations are those defined above which occur within a span of five feet or less. Pipe shall be measured as the percent difference between the maximum and minimum pipe diameters. For gauging

West Branch Regional Authority 02310-9 January 2026 purposes, ovality locations are those defined above which exceed a span of five

(5) feet.

E. Ream and Pullback:

1. Reaming: Reaming operations shall be conducted to enlarge the pilot after acceptance of the pilot bore. The number and size of such reaming operations shall be conducted at the discretion of the Contractor.

2. Pulling Loads: The maximum allowable pull exerted on the HDPE pipelines shall be measured continuously and limited to the maximum allowed the pipe manufacturer so that the pipe or joints are not over stressed.

3. Torsion and Stresses: A swivel shall be used to connect the pipeline to the drill pipe to prevent torsional stress from occurring in the pipe.

4. The lead end of the pipe shall be closed during the pullback operation.

5. Pipeline Support: The pipelines shall be adequately supported by rollers and side booms and monitored during installation so as to prevent over stressing or buckling during the pullback operation. Such support/rollers shall be spaced at a maximum of 60 feet on centers, and the rollers to be comprised of a non-abrasive material arranged in a manner to provide support to the bottom and bottom quarter points of the pipeline for free movement of the pipeline during pullback. Surface damage shall be repaired by the Contractor before pulling operations resume.

6. The Contractor shall at all times handle the HDPE: pipe in a manner that does not over stress the pipe. Vertical and horizontal curves shall be limited so that wall stresses do not exceed fifty percent (50%) of yield stress for flexural bending of the HDPE pipe. If the pipe is buckled or otherwise damaged, the damaged section shall be removed and replaced by the Contractor at his expense. The Contractor shall take appropriate steps during pullback to ensure that the HDPE pipe will be installed without damage.

F. Handling Drilling Fluids and Cuttings:

1. During the drilling, reaming, or pullback operations, the Contractor shall make adequate provisions for handling the drilling fluids, or cuttings at the entry and exit pits. To the greatest extent practical, these fluids must not be discharged into the waterway. When the Contractor's provisions for storage of the fluids or cuttings on site are exceeded, these materials shall be hauled away to a suitable legal disposal site. The Contractor shall conduct his directional drilling operation in such a manner that drilling fluids are not forced through the subbottom into the

West Branch Regional Authority 02310-10 January 2026 waterway. After completion of the directional drilling work, the entry and exit pit locations shall be restored to original conditions. The Contractor shall comply with all permit provisions.

2. Pits constructed at the entry or exit point area shaII be so constructed to completely contain the drill fluid and prevent its escape to the beach or waterway.

3. The Contractor shall utilize drilling tools and procedures which will minimize the discharge of any drill fluids. The Contractor shall comply with all mitigation measures listed in the required permits and elsewhere in these Specifications.

4. To the extent practical, the Contractor shall maintain a closed loop drilling fluid system.

5. The Contractor shall minimize drilling fluid disposal quantities by utilizing a drilling fluid cleaning system which allows the returned fluids to be reused.

6. As part of the installation plan specified herein before, the Contractor shall submit a drilling fluid plan which details types of drilling fluids, cleaning and recycling equipment, estimated flow rates, and procedures for minimizing drilling fluid escape.

3.02 DRILLING OPERATIONS

The Contractor shall prepare a plan to be submitted for Engineer approval which describes the noise reduction program, solids control plant, pilot hole drilling procedure, the reaming operation, and the pullback procedure. All drilling operations shall be performed by supervisors and personnel experienced in horizontal directional drilling. All required support, including drilling tool suppliers, survey systems, mud cleaning, mud disposal, and other required support systems used during this operation shall be provided by the Contractor.

Drill pipe shall be API steel drill pipe, Range 2, Premium Class or higher. Grade S-135 in a diameter sufficient for the torque and longitudinal loads and fluid capacities required for the work. Only drill pipe inspected under API's. Recommended Practice Specification API RP 7e, within 30 days prior to start and certified as double white band or better shall be used.

A smoothly drilled pilot hole shall follow the design centerline of the pipe profile and alignment described on the construction drawings.

The position of the drill string shall be monitored by the Contractor with the downhole

West Branch Regional Authority 02310-11 January 2026 survey instruments. Contractor shall compute the position in the X- and Y-axis relative to ground surface from downhole survey data a minimum of once per length of each drilling pipe (approximately 30-foot interval). Deviations from the acceptable tolerances described in the Specifications shall be documented and immediately brought to the attention of the Engineer for discussion and/or approval. The profile and alignment defined on the construction drawings for the bores define the minimum depth and radius of curvature. At no point in the drilled profile shall the radius of curvature of the bore be less than 1,600 feet. The Contractor shall maintain and provide to the Engineer, upon request, the data generated from the downhole survey tools in a form suitable for independent calculation of the pilot hole profile.

Between the water's edge and the entry or exit point the Contractor shall provide and use a separate steering system employing a ground survey grid system, such as "TRU- TRACKER" or equal wherever possible. The exit point shall fall within a rectangle 3 feet wide and 20 feet long centered on the planned exit point.

During the entire operation, waste and leftover drilling fluids from the pits and cuttings shall be dewatered and disposed of in accordance with all permits and regulatory agencies requirements. Remaining water shall be cleaned by Contractor to meet permit requirements.

Technical criteria for bentonite shall be as given in API Spec. 13A, Specification for Oil Well Drilling Fluids Material for fresh water drilling fluids. Any modification to the basic drilling fluid involving additives must describe the type of material to be used and be included in Contractor's drilling plan presented to the Engineer. The Owner retains the right to sample and monitor the waste drilling mud, cuttings and water.

B. Environmental Provisions:

The Horizontal Directional Drilling operation is to be operated in a manner to eliminate the discharge of water, drilling mud and cuttings to the adjacent creek or land areas involved during the construction process. The Contractor shall provide equipment and procedures to maximize the recirculation or reuse of drilling mud to minimize waste. All excavated pits used in the drilling operation shall be lined by Contractor with heavy duty plastic sheeting with sealed to prevent the migration of drilling fluids and/or ground water.

The Contractor shall visit the site and must be aware of all structures and site limitations at the directional drill crossing and provide the Engineer with a drilling plan outlining procedures to prevent drilling fluid from adversely affecting the surrounding area.

The general work sides of the crossing shall be enclosed by a berm to contain unplanned spills or discharge.

Waste cuttings and drilling mud shall be processed through a solids control plant

West Branch Regional Authority 02310-12 January 2026 comprised as a minimum of sumps, pumps, tanks, desalter/desander, centrifuges, material handlers, and haulers all in a quantity sufficient to perform the cleaning/separating operation without interference with the drilling program. The cuttings and excess drilling fluids shall be dewatered and dried by the Contractor to the extent necessary for disposal in offsite landfills. Water from the dewatering process shall be treated by the Contractor to meet permit requirements and disposed of locally. The cuttings and water for disposal are subject to being sampled and tested. The construction site and adjacent areas will be checked frequently for signs of unplanned leaks or seeps.

Equipment (graders, shovels, etc.) and materials (such as groundsheets, hay bales, booms, and absorbent pads) for cleanup and contingencies shall be provided in sufficient quantities by the Contractor and maintained at all sites for use in the event of inadvertent leaks, seeps or spills.

Waste drilling mud and cuttings shall be dewatered, dried, and stockpiled such that it can be loaded by a front-end loader, transferred to a truck and hauled offsite to a suitable legal disposal site. The maximum allowed water content of these solids is fifty percent (50%) of weight. Due to a limited storage space at the worksites, dewatering and disposal work shall be concurrent with drilling operations. Treatment of water shall satisfy regulatory agencies before it is discharged.