9-Project Manual.pdf

Ben-Taub Underground Pipe Replacement 27198-00

100% Construction Documents

2025-12-03

SEALS PAGE 00 01 07 - 1

SECTION 00 01 07

SEALS PAGE

I. MECHANICAL ENGINEER:

1. Name: Xin Zhang

2. Title: Mechanical Engineer

3. Company: AEI

4. Registration: Texas, 106477

III. CIVIL ENGINEER:

5. Name: Daniel Falkenstine

6. Title: Principal

7. Company: Walter P Moore

8. Registration: 1856

Table of Contents

TOC

100% Construction Documents

Ben-Taub Underground Pipe Replacement

12-03-2025

TABLE OF CONTENTS

DIVISION 22 - PLUMBING AND PIPING

22 05 20 EXCAVATION AND BACKFILL

22 14 00 GREASE WASTE AND VENT SYSTEM

DIVISION 31- EARTHWORK

31 23 33 TRENCHING, BACKFILLING AND COMPACTION

31 25 00 EROSION AND SEDIMENTATION CONTROL

31 41 33 TRENCH SAFETY

DIVISION 33 – UTILITIES

33 30 00 SANITARY SEWER

2025-12-03 1

SECTION 20 05 20

EXCAVATION AND BACKFILL

GENERAL

1.1 DESCRIPTION

A. This Section lists methods and materials for trench excavation and backfill for plumbing piping systems inside and outside the building.

B. Refer to report, available from Construction Manager for data on soil conditions.

1.2 RELATED WORK

A. Division 31 - Earthwork

1.3 REFERENCE

A. Work under this Section is subject to requirements of Contract Documents including General Conditions of Contract, Supplementary Conditions, and sections under Division 01 General Requirements.

1.4 SUBMITTALS

A. List of materials to be used for backfill.

PRODUCTS

2.1 FILL MATERIAL

A. Type 1 Fill:

1. Material from excavation separated from materials, which do not compact by tamping and rolling. No stones larger than 3” and no building, organic, corrosive or frozen materials.

B. Type 2A Fill:

1. Sand or gravel materials with none larger than 2” and of that portion passing #4 sieve less 5% to pass #200 sieve.

C. Type 2B Fill:

1. Sand or gravel materials with none larger than 1/2” and of that portion passing #4 sieve less 5% to pass #200 sieve.

D. Type 3 Fill:

1. Gravel of rounded to subangular shape, screened, which will pass 0.75” sieve and retained on #4 sieve.

E. Type 4 Fill:

1. Pit run rock or gravel with maximum stone size of 1”.

F. Type 5 Fill:

1. Pea gravel, screened, which will pass 0.375” sieve and retained on #4 sieve.

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G. Type 6 Fill:

1. Soils Engineer approved fill material, backfilled and compacted beneath building footprint.

EXECUTION

3.1 PREPARATION

A. Establish grade lines and locations of mains and manholes. Provide necessary stakes and batter boards.

B. Verify invert elevations of existing utilities prior to excavation for new utility piping.

3.2 EXCAVATION

A. Provide excavation for all underground work, including piping, manholes, catch basins, tanks, concrete structures, etc., unless otherwise shown or specified. Lay piping in open trench except when Architect gives written permission for tunneling.

B. Include all necessary clearing; tree removal; grubbing; pavement removal; substructure removal such as walls, footings and piers and all incidental work such as tunneling, sheet piling, shoring, underpinning, pumping, bailing and transportation. Coordinate excavation extending beyond construction limits with Construction Manager and Owner.

C. Blasting is not allowed on this project without written permission of Architect and Owner.

D. Remove all excess excavation material from site unless directed otherwise. Dispose of excess excavation material on site in location designated by Construction Manager.

E. Use mechanical methods to remove rock in trenches for piping systems.

F. Include rock excavation in the Bid unless otherwise indicated.

3.3 PIPE INSTALLATION

A. Keep underground piping to proper line and grade and sealed at all times to prevent entrance of animals or foreign matter.

B. Provide bracing and sheet piling as necessary to support trenches. Comply with Local Regulations, applicable provisions of OSHA Regulations on trenching, or with provisions of “Manual of Accident Prevention in Construction” published by Associated General Contractors of America.

C. Under no circumstances lay pipe or install appurtenances in water. Keep trench free from water until pipe joint material has hardened.

D. Presence of ground water in soil or necessity of sheet piling or bracing trenches shall not constitute condition for which any increase may be made in Contract price, except when sheet piling is left in place on written order of Owner, Contract price will be adjusted.

E. Cut off sheet piling left in place not less than 2” below new finished grade. Do not remove sheet piling until trench is substantially backfilled.

F. Install underground plastic pipe per ASTM D2321.

G. Place underground piping outside and inside building in open excavated trenches. Where trench bottom does not contain stones larger than 1” in size or where bedrock is not encountered, trench

2025-12-03 3 may be excavated to final pipe grade. Where bedrock or stones larger than 1” is encountered, excavate entire length of trench to depth 4” below final pipe grade elevation and provide 4” of pipe bedding material compacted to minimum of 90% Standard Proctor Density consisting of Type 2B, 3 or 5 fill to establish final pipe grade. Shape bedding for clearance for all joints and fittings, tamped in place and graded evenly to insure uniform bearing for full length of pipe. Do not support piping by blocking, planking or mounding of bedding material.

3.4 BACKFILL

A. Exterior:

1. Backfill outside building including all piping beyond construction limits only after piping and appurtenances have been inspected, recorded, tested and approved. Backfill around pipe by hand to depth of 12” above top of pipe with Type 2B, 3 or 5 fill in 6” layers. Take care not to disturb pipe or damage pipe coating. Do not use Type 3 fill where it will come in contact with polyethylene encasement specified in Section 21 1114 - Exterior Fire Suppression Piping Systems and Section 22 1114 - Exterior Services. Compact backfill thoroughly with compactor of suitable weight or with approved mechanical tamper. No flooding or jetting with water is allowed.

2. Place backfill from 12” above pipe in layers not exceeding 8” in depth with Type 1 fill.

Compact backfill material to the same density as surrounding area prior to that of excavation.

3. When excavating through areas which are to become walks, roads, driveways or parking areas of concrete, bituminous or exposed gravel surfacing or such areas are existing to remain; backfilling from 12” above pipe to subgrade shall be with Type 2A, 2B, 3 or 4 fill.

Backfill in 12” layers and compact with mechanical means to density 95% modified proctor.

Frequency of compaction testing shall be determined by testing consultant, based on site conditions, materials and workmanship.

4. When excavation occurs on public property or areas beyond property line, all excavation, pipe laying, backfilling, grading and surfacing shall conform as herein specified, except additional requirements for public utility or other authorities shall be complied with when in order. Check with each utility and incorporate cost of any additional requirements in Base Bid.

B. Interior:

1. Backfill inside building only after piping and appurtenances have been inspected and approved. Backfill to 12” above pipe with Type 2B, 3 or 5 fill in 6” layers. Remainder of backfill shall be Type 2A, 2B, 3, 4, or 6 fill in 12” layers.

2. Install lines passing under foundations with minimum of 1-1/2” clearance to concrete and insure there is no disturbance of bearing soil.

3.5 ROCK EXCAVATION

A. Consider material over one cubic yard in size encountered during excavation as rock. Rock excavation will be paid as extra if it cannot be removed by 200 net hp crawler tractor with ripper attachment all in good running condition and operated by an experienced individual.

B. Excavate rock to 4” below intended pipe invert.

3.6 FINISHING

A. On completion of trenching and backfilling operations, restore grades to original elevation or to new subgrade elevation.

END OF SECTION

SECTION 22 1400

GREASE WASTE AND VENT SYSTEM

GENERAL

1.1 DESCRIPTION

A. This Section includes materials and methods for grease waste and vent piping within building and including piping to grease interceptor outside building.

1.2 RELATED WORK

A. Section 20 0520 - Excavation and Backfill

1.3 REFERENCE

A. Work under this Section is subject to requirements of Contract Documents including General Conditions, Supplementary Conditions, and sections under Division 01 General Requirements.

1.4 QUALITY ASSURANCE

A. Order piping with each length marked with manufacturer's name or trademark and type of pipe;

with each shipping unit marked with purchase order number, metal or alloy designation, temper, size, and supplier's name.

B. Installed material not meeting specification requirements must be replaced with material that meets these specifications without additional cost to Owner.

1.5 DELIVERY, STORAGE, AND HANDLING

A. Promptly inspect shipments to ensure material is undamaged and complies with Specifications.

B. Cover pipe to prevent corrosion or deterioration while allowing sufficient ventilation to avoid condensation. Do not store materials directly on grade. Protect pipe, tube, and fitting ends from damage. End caps shall remain in place. Protect fittings by storage inside or by durable, waterproof, above ground packaging.

C. Offsite storage agreements will not relieve Contractor from using proper storage techniques.

D. Storage and protection methods must allow inspection to verify products.

1.6 SUBMITTALS

A. Manufacturer's technical data for the following:

1. Pipe and fittings

2. Joints

3. Cleanouts

PRODUCTS

2.1 MATERIALS

A. Materials herein specified shall be new, unless otherwise noted.

2.2 PIPE, FITTINGS, AND JOINTS

A. Interior Underground (10”) and Smaller:

1. Polyvinyl Chloride (PVC):

a. Pipe:

1). Schedule 40, Class 12454 (PVC 1120), ASTM D1785

b. Fittings: Socket fitting, DWV patterns, ASTM D3311. Fabricated fittings (10”) and larger shall be per ASTM F1866.

c. Joints: Primer, low VOC, ASTM F656; solvent cement, low VOC, ASTM D2564

B. Adaptor Couplings for Joining Dissimilar Pipe Materials:

1. Acceptable Manufacturers: Fernco and Mission.

2. (1” through 6”) diameter: Fernco Proflex 3000 Series shielded coupling with neoprene gasket, stainless steel shield, and stainless steel clamping bands. Adaptor couplings shall be specifically designed for pipe materials being joined.

3. (8” through 10”) diameter: Fernco 1000 Series flexible coupling with elastomeric PVC or neoprene gasket and stainless steel clamping bands. Adaptor couplings shall be specifically designed for pipe materials being joined.

2.3 CLEANOUTS

A. Blucher, Josam, Smith, or Zurn, equal to number listed in Drains and Cleanout Schedule.

B. Cleanout material shall be similar to pipe material.

2.4 GREASE INTERCEPTOR

A. Include the following for a low profile hydromechanical grease interceptor for below grade application.

B. Schier Great Basin® grease interceptor model # GB-1500 shall be lifetime guaranteed and made in USA of seamless, molded polyethylene with minimum 7/16" uniform wall thickness. Interceptor shall be furnished for above or below-grade installation with adjustable cover adapter and Safety Star® access restrictor built into each cover adapter and temporary jobsite cover. Interceptor shall be certified for hydromechanical performance to ASME A112.14.3 (Type D) and CSA B481.1 and IAPMO/ANSI Z1001-2021. Flow control not required. Interceptor flow rate shall be 100 GPM or 200 GPM, or up to 1,500 GPM in high-flow applications. Interceptor grease capacity shall be 10,061 lbs. @ 100 GPM or 9,446 lbs. @ 200 GPM, or 3,000 lbs. @ 1,500 GPM (factory rated). Interceptor grease capacity at 99% efficiency shall be 9,897 lbs. @ 100 GPM or 8,093 lbs. @ 200 GPM. Covers are chosen by the contractor. Injection-molded pedestrian cover shall provide water/ gas-tight seal and have minimum 2,000 lbs. load capacity and center bolt. Cast iron, traffic cover shall provide water/ gas-tight seal and have minimum 16,000 lbs. load capacity.

Interceptor shall be furnished with Fast Pitch® riser model # FP24 as needed to extend cover and adapter to finish grade.

C. Sampling Port: Schier Sewer Viewer® inspection port model # SV24 shall be lifetime guaranteed and made in USA of seamless, molded polyethylene with minimum 1/4" uniform wall thickness.

Inspection port shall be furnished for above or below grade installation with adjustable cover adapter and Safety Star® access restrictor built into cover adapter and temporary jobsite cover.

Covers are chosen by the contractor. Injection-molded pedestrian cover shall provide water/ gas-tight seal and have minimum 2,000 lbs. load capacity and center bolt. Cast iron, traffic cover shall provide water/ gas-tight seal and have minimum 16,000 lbs. load capacity. Interceptor shall be furnished with Fast Pitch® riser model # FP24 as needed to extend cover and adapter to finish grade.

EXECUTION

3.1 INSTALLATION - GENERAL

A. Install pipe and fittings in accordance with reference standards, manufacturer's recommendations and recognized industry practices.

B. Provide rigid bracing to resist movement of upstream pipe for horizontal pipes (4”) and larger with changes in direction greater than 45 degrees.

C. Avoid cleanout plugs in ceiling cavities. Where cleanouts are required, extend pipe to floor cleanouts in slab above.

D. Connect piping to fixtures, each piece of equipment, and drains. Install required piping as shown on drawings.

E. Grade horizontal lines with minimum of (1/8” per ft), except piping (2”) diameter or smaller which shall be run at (1/4” per ft) slope.

F. Grade horizontal lines with minimum of (1/4” per ft), except piping (4”) diameter or larger which may be run at (1/8” per ft) slope with approval of local authority.

G. Install piping parallel with building lines and at heights, which do not obstruct any portion of window, doorway, stairway, or passageway, except, as may be shown on plans. Install overhead piping as high as possible.

H. Grade vent pipe for complete drainage by gravity to soil or waste pipes. Vent terminations shall be set true and level. Locate vent piping at least (10 ft) away from window, door or intake openings. Coordinate closely with roofing contractor to prevent damage to roofing membrane.

Flashing shall be in accordance with requirements of roofing manufacturer.

I. Where interferences develop, offset or reroute piping as required to clear interferences.

Coordinate locations of plumbing piping with piping, ductwork, conduit and equipment of other trades to allow sufficient clearances. Consult drawings for exact location of pipe spaces, ceiling heights, door and window openings, or other architectural details before installing piping.

J. Provide protective sleeve covering of elastomeric pipe insulation, where piping and/or fittings are embedded in masonry or concrete.

K. Maintain piping in clean condition internally during construction.

L. Mitered ells, notched tees, and orange peel reducers are not allowed. Bushings are not allowed on threaded piping.

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M. Do not route piping through transformer vaults or above transformers, panelboards, or switchboards, including required service space for this equipment, unless piping is serving this equipment.

N. Set cleanouts true and level and protect properly throughout construction.

O. Set floor drains true and level and protect properly throughout construction. Weep holes shall be filled with removable material and kept free from concrete and other debris during construction.

Weep holes shall be cleaned out for final working order. Provide safing for floor drains installed in elevated slabs.

P. Provide plugs or caps for pipe openings during construction to prevent debris from entering pipe.

Temporary plug shall be plastic cap or equivalent.

Q. Install components in accordance with manufacturer's instructions and approved product data submittals.

3.2 UNDERGROUND WARNING TAPE

A. Provide warning tape for exterior buried sewers per Section 20 0553.

3.3 THREADED PIPE

A. Make joints for threaded pipe by cutting pipe square and reaming inside. Threads shall be cut so that end of pipe extends to shoulder of fitting.

B. Exposed threads shall not exceed 3 in number and shall be painted with heavy coat of corrosion inhibiting material.

C. Use only approved joint compounds, thread lubricant, or Teflon tape sparingly and only on outer threads.

3.4 TESTING

A. Refer to Testing paragraph of Section 20 0000 - General Mechanical Requirements.

B. Water test may be applied to system either in its entirety or in sections. Piping shall be tightly plugged and submitted to (10 ft) head of water located at highest point. Provide separate standpipe above highest point being tested or extend system to obtain required (10 ft) head of water. Head shall be maintained for at least 30 minutes before inspection starts.

C. Defective work or material shall be replaced or repaired as necessary and inspection and test repeated. Repairs shall be made with new materials. No caulking of threaded joints or holes will be allowed.

D. Do not backfill pipe until successfully tested.

E. Testing with air will not be allowed.

U:\Master Documents\Master Specifications (Div 20-28)\Plumbing (Div 22)\22 1400 Grease Waste and Vent Systems.doc

SECTION 31 23 33

TRENCHING, BACKFILLING AND COMPACTION

PART 1 - GENERAL

1.1 SCOPE

A. This Section specifies the requirements for excavating and backfilling for storm sewer, sanitary sewer, water distribution lines, and all related appurtenances. Excavation and backfill shall be in conformance with the locations, lines, elevations and grades shown on the plans. This section also specifies the requirements for clay plugs that must be installed near building face on all utility trenches including water, storm sewer, sanitary sewer, mechanical, electrical, telecom, data, plumbing and other utility trenches for slab on grade and structural first floor building projects.

B. Subsurface data is available from the Owner. Contractor is urged to carefully analyze the site conditions. A Geotech report is not available at the moment.

1.2 APPLICABLE PUBLICATIONS

A. The following specifications and standards of the latest issue listed below, but referred to thereafter by basic designation only, form a part of this specification to the extent required by the reference thereto.

1. American Society for Testing and Materials (ASTM).

a. D 698 – Laboratory Compaction Characteristics of Soil Using Standard Effort.

b. D 1556 Density and Unit Weight of Soil in Place by the Sand-Cone Method.

c. D 4253 - Maximum Index Density and Unit Weight of Soils using a Vibratory

Table.

d. D 4254 - Minimum Index Density and Unit Weight of Soils in Calculation of

Relative Density.

e. D2321-89 Standard Practice for Underground Installation of Thermoplastic

Pipe for Sewers and Other Gravity-Flow Applications

2. Texas Department of Transportation (TxDOT) Test Procedures

a. Tex-110-E Particle Size Analysis of Soils

b. Tex-120-E Soil Cement Testing

1.3 RELATED WORK SPECIFIED ELSEWHERE

A. Drawings and general provisions of the Contract, including A-procurement and Contracting Requirements, Division 00 and Division 01 apply to this section.

1. Section 31 41 33 - Trench Safety

2. Section 33 30 00 – Sanitary Sewer

1.4 SUBMITTALS

A. Material Test Reports: From a qualified testing agency indicating and interpreting test results for compliance of the following with requirements indicated:

1. Classification according to ASTM D 2487 of each on-site soil material proposed for backfill

B. Pre-excavation Photographs or Videotape: Show existing conditions of adjoining construction and site improvements, including finish surfaces that might be misconstrued as damage caused by earthwork operations. Submit before excavation begins.

1.5 PROJECT CONDITIONS

A. Existing Utilities: Do not interrupt utilities serving facilities occupied by Owner or others unless permitted in writing by Owner and then only after arranging to provide temporary utility services according to requirements indicated

1. Notify Owner not less than five days in advance of proposed utility interruptions.

2. Do not proceed with utility interruptions without Owner’s written permission.

3. Contact utility-locator service for area where Project is located before excavating.

B. Demolish and completely remove from site existing underground utilities indicated to be removed. Coordinate with utility companies to shut off services if lines are active.

C. Utilities have been located from surveys and available existing records. Not all utilities may be shown on the Drawings. Locate all utilities prior to beginning any construction activities.

D. Where utilities require adjustment or relocation to construct the Work, and those utilities are shown on the Drawings, relocation or adjustment is a part of the Work and shall be completed at no additional expense to the Owner.

E. Where utilities require adjustment or relocation to construct the Work, and those utilities are not shown on the Drawings, notify Architect before proceeding. Relocate or adjust utility as directed. Utility relocation and/or adjustment will be paid for according to the Contract provisions for changes in Work.

F. If utility is damaged by Contractor, notify utility owner and Architect immediately. Repair or replacement of utilities damaged by Contractor, whether utilities are shown on the drawings or not shown on the drawings, shall be Contractor's expense.

1.6 PERMITS

A. Prior to commencement of work, the Contractor shall be responsible for obtaining, at the contractors own expense, all construction permits necessary to complete the project according to the plans and specifications.

1.7 DEFINITIONS

A. Excavation consists of the removal of material encountered to subgrade elevations and the reuse or disposal of materials removed.

B. Subgrade: The uppermost surface of an excavation, including excavation for trenches, or the top surface of a fill or backfill immediately below base course, pavement, or topsoil materials.

C. Borrow: Soil material obtained off-site when sufficient approved soil material is not available from excavations.

D. Base Course: The layer placed between the subgrade and surface pavement in a paving system.

E. Unauthorized excavation consists of removing materials beyond indicated subgrade elevations or dimensions without direction by the Owner’s rep. Unauthorized excavation, as well as remedial work directed by the Owner’s Rep shall be at the Contractor's expense.

F. Structures: Buildings, footings, foundations, retaining walls, slabs, tanks, curbs, mechanical and electrical appurtenances, or other man-made stationary features constructed above or below ground surface.

G. Utilities include underground pipes, conduits, ducts, and cables, as well as underground services within building lines.

H. Unforeseen Excavation: Excavation of material, regardless of its character or nature, below the subgrade elevation required to construct the work as indicated on the drawings or specified herein.

I. Bedding Material: Granular material utilized to bed piped utilities placed in trench excavations.

1.8 QUALITY ASSURANCE

A. Pre-Excavation Conference: Conduct conference at Project site to comply with requirements in Division 01.

B. Codes and Standards: Perform earthwork complying with requirements of authorities having jurisdiction.

C. Testing and Inspection Service: Owner will employ a qualified independent geotechnical engineering testing agency to classify proposed on-site and borrow soil materials to verify that soils comply with specified requirements and to perform required field and laboratory testing.

PART 2 - PRODUCTS

2.1 EARTH BACKFILL

A. Earth backfill shall be native soils free of debris, trash, rocks over 2 inches in diameter and other objectionable material.

2.2 CEMENT STABILIZED SAND BACKFILL

A. Cement stabilized sand material shall contain clean bank sand meeting TxDOT Test Method TEX-110-E, water and a minimum of 7% hydraulic cement based on the dry weight of the aggregate meeting TxDOT Test Method Tex-120-E.

B. The sand cement mixture shall produce a minimum unconfined compressive strength of one hundred pounds per square inch (100psi) in forty eight hours, when compacted to ninety fire percent (95%) of Standard Proctor density (ASTM D558), without additional moisture control and when cured in plastic bags at a temperature of 73.4 degrees F at plus or minus 3 degrees F and tested in accordance with ASTM D1633.

2.3 SAND BACKFILL

A. Clean bank sand meeting TxDOT Test Method TEX-110-E.

2.4 WATER

A. Water used for mixing or curing shall be reasonably clean and free of oil, salt, acid, alkali, sugar, vegetable matter or other substances injurious to the finished product.

B. Water sources other than the local municipal domestic water supply must be approved by the Owner.

C. If onsite reclaimed water sources are used, tanks and appurtenance must be clearly marked with the words “non-potable” water.

PART 3 - EXECUTION

3.1 PREPARATION

A. Protect structures, utilities, sidewalks, pavements, and other facilities from damage caused by settlement, lateral movement, undermining, washout, and other hazards created by earthwork operations.

B. Protect subgrades and foundation soils against freezing temperatures or frost. Provide protective insulating materials as necessary.

C. Provide erosion-control measures to prevent erosion or displacement of soils and discharge of soil-bearing water runoff or airborne dust to adjacent properties and walkways.

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3.2 EXCAVATION

A. General:

1. All utility trenches shall be constructed in conformance with OSHA trench safety standards.

2. Sheeting and shoring shall be accomplished to the extent necessary to maintain the sides of the trench in a vertical position throughout the construction period for trenches five (5) feet in depth or deeper. Where approved, trench sides may be laid back in lieu of shoring to meet OSHA safety standards.

3. Utilities shall not be constructed or laid in a trench in the presence of water. All water shall be removed from the trench sufficiently prior to the line placing operation to insure a dry, firm bed on which to place the utility line.

4. Unclassified Excavation: Excavation is unclassified and includes excavation to subgrade elevations regardless of the character of surface and subsurface conditions encountered, including rock, soil materials, and obstructions.

a. If excavated materials intended for fill and backfill include unsatisfactory soil materials and rock, replace with satisfactory soil materials.

b. Remedial work due to over-excavation including provision of suitable and stable backfill meeting the degree of compaction required shall be at the Contractor’s expense.

5. Borrow Material: If excavated materials of a suitable nature are not of sufficient quantity to complete the work, provide borrow material in sufficient quantity to complete the work at no additional cost to the Owner.

6. Disposing of Excavated Material: Dispose of excess satisfactory soil material and all unsatisfactory soil material and rock obtained from excavations in accordance with the provisions of this Section.

7. Where utilities are in fill, compact fill material to 95% standard proctor maximum dry density at least 12” above the top of the proposed utility prior to excavation of trench.

8. Where indicated widths of utility trenches are exceeded, provide stronger pipe, or special installation procedures, as required by Owner’s Rep. Unauthorized excavation, as well as remedial work directed by the Owner’s Rep, shall be at the Contractor’s expense.

B. Sewer Trenches:

1. For pipe sizes less than 42" in diameter, the minimum trench width shall be outside diameter of pipe plus 18 inches.

2. For pipe sizes 42" in diameter and larger the minimum trench width shall be outside diameter of pipe plus 24 inches.

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3. Trenches shall be excavated to a depth at least 6" below the barrel of pipe, and then the pipe bedding shall be placed as shown on the appropriate details contained with the plans and as described in paragraph 3.3 A. of this section.

C. Appurtenances

1. Excavation for manholes, tie-in to existing facilities and similar structures shall be sufficient to leave at least 12" clear between the outer surfaces and the embankment or sheeting that may be used to hold and protect the banks. Any over depth excavation below such appurtenances shall be refilled with cement stabilized sand, as directed, at no additional cost to Owner.

D. Water line Trenches:

1. Water lines must be a minimum of four feet in depth from the top of proposed grade to the top of pipe, unless otherwise shown on the plans.

2. Trench width for water lines shall be a minimum of the outside pipe diameter plus 18 inches.

3. Trenches shall be excavated to a depth of at least 6 inches below the barrel of pipe, and then the pipe bedding shall be placed as shown on the details within the plans and as described in paragraph 3.3 B. of this section.

3.3 PIPE BEDDING AND BACKFILL

A. Storm and sanitary sewer trenches:

1. Pipe shall be bedded in trench in accordance with the details shown on the plans.

When pipe has greater than twelve (12) feet of cover, use Class A bedding and backfill.

2. Cement stabilized sand shall be per Part 2.2.A of this specification, mixed in a mill type mixer. When the details call for cement stabilized sand bedding, the material shall extend from a point 6" below the bottom of the pipe to the level of the spring line. This material cannot be used after is loses its moisture content.

3. The cement stabilized sand shall be thoroughly rodded after being placed in trench.

4. Bedding, sewer pipe and initial backfill over the top of pipe must be placed in a single day's operation for any given portion of pipe. Initial backfill shall be placed to one foot above the top of pipe for earth backfill and 6 inches over the top of pipe for cement stabilized sand backfill.

5. Remainder of trench backfill shall be placed the next day or later in 8" lifts, after pipe is laid in conformance with these specifications and the details on the plans.

6. Backfill shall be placed in uniform layers not to exceed 8" loose depth, and compacted to a minimum of 95 percent of Standard Maximum Density (ASTM D

698) at the proper moisture content specified in the Geotechnical report for this project.

2025-12-03 7

7. Backfill, under pavement and to one foot from outer edge, shall be cement stabilized sand of the type and method described under paragraph 3.3 A.1 through 5, above, up to one foot below subgrade elevation. Remainder of backfill to subgrade to be as specified in paragraph 3.3 A.5. above and stabilized where required.

B. Water line Trenches

1. Pipe bedding shall consist of 6 inches of clean sand placed before the pipe is laid.

2. After laying pipe and insuring that the pipe is properly placed and supported by the sand bedding, clean sand backfill shall be placed to 6 inches above the top of pipe.

The sand backfill shall be thoroughly rodded and tamped for compaction.

3. For water lines beneath pavement and to one foot horizontally from the outer edge of pavement, the remainder of the trench backfill shall be clean sand placed up to the top of subgrade, thoroughly rodded and tamped.

4. For water lines not beneath pavement or within one foot horizontally from the outer edge of pavement, the remainder of the trench backfill shall be earth fill paced in uniform layers not to exceed 8" loose depth, each lift to be compacted to a minimum of 95 percent of Standard Density (ASTM D698) at the proper moisture content specified in the Geotechnical report for this project. All earth backfill to be placed the next day or later after the pipe is laid.

C. Bentonite Clay Plug for All Utility Trenches (water, storm, sanitary, mechanical, electrical, telecom, plumping, etc.)

1. All trenches must have a bentonite granular clay plug installed to reduce the transmission of ground water under slab on grade buildings and structural first floor buildings.

a. The plug must be installed at a distance of one foot beyond the face of the building foundation and be a minimum of one-foot wide.

b. The plug must extend 6” beneath utility trench into undisturbed soil. This portion of the clay plug must be installed prior to the installation of the utility pipe.

c. The plug must extend across the entire trench width and extend 6” into undisturbed soil beyond the trench width. Install bentonite clay plug and the utility pipe at the same time.

d. The plug must extend to within 12” of finished grade. A clay plug cap consisting of material with a plasticity index greater than 15 and a liquid limit in excess of 30 shall be placed on top of the bentonite granular clay plug.

This clay plug cap shall fill the remaining 12” up to finished grade and be placed up to the edge of the building.

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3.4 STORAGE OF SOIL MATERIALS

A. Stockpile borrow materials and satisfactory excavated soil materials. Stockpile soil materials without intermixing. Place, grade, and shape stockpiles to drain surface water.

Cover to prevent windblown dust.

1. Stockpile soil materials away from edge of excavations. Do not store within drip line of remaining trees.

3.5 FIELD QUALITY CONTROL

A. General: Testing shall be the responsibility of Owner and costs of initial testing will be paid by Owner. Cost of subsequent testing necessary due to non-compliance with Specifications shall be paid by Contractor.

B. Density Test:

1. Density tests shall be performed by representatives of Owner’s Testing Agency.

2. Frequency and scope of testing shall be established by Geotechnical Engineer, and as required by local jurisdictional authority.

3. If Geotechnical Engineer has not established a frequency of testing in the Geotechnical Report, testing shall be at every 100 linear foot of trench at a minimum of one per lift and a minimum of one per day.

4. Tests shall be performed in accordance with the referenced Standards.

5. Laboratory tests for moisture-density relations shall be determined in accordance with ASTM D 1557. A minimum of one test shall be performed for each major soils type. In addition, sufficient number of retests or check points shall be performed to evaluate accuracy of maximum density values being used.

6. Field in-place density shall be determined in accordance with ASTM Test Methods D 1556 or D 2922, and the moisture-density relations shall be determined in accordance with ASTM Test Method D 1557.

7. Reopen improperly compacted trenches to depth directed, then refill and compact to the specified density at no additional cost to Owner

SECTION 31 25 00

EROSION AND SEDIMENTATION CONTROL

PART 4 - GENERAL

4.1 SCOPE OF WORK

A. This Section pertains to the provisions for the control of erosion in the construction area and in stockpile areas including seeding as required and shown on the drawings. All areas where existing vegetation and grass cover have been bared by construction activities shall be protected from erosion.

B. Contractor is responsible for meeting all local, state and federal regulations regarding erosion control including the applicable provisions of the National Pollution Discharge Elimination System, Phase II, regulations from the Clean Water Act.

4.2 RELATED WORK SPECIFIED ELSEWHERE

A. Drawings and general provisions of the Contract, including A-procurement and Contracting Requirements, Division 00 and Division 01 apply to this section.

B. Section 31 23 33 Trenching, Backfilling and Compaction

4.3 PERMITS (NOT USED)

4.4 APPLICABLE PUBLICATIONS (NOT USED)

4.5 PROTECTION OF ADJACENT WORK (NOT USED)

4.6 DEFINITIONS

A. Best Management Practices (BMP's) means physical facilities schedules of activities, prohibition of practices, maintenance procedures, and other management practices , when properly designed, installed, and maintained, will be effective to prevent or reduce the discharge of pollution associated with construction activities. BMP's also include treatment requirements, operating procedures, and practices to control site runoff, spillage or leaks, sludge or waste disposal, or drainage from raw material storage.

B. Block Sodding: Sodding for erosion control and for final stabilization shall consist of providing and planting Bermuda grass, Saint Augustine grass, or other acceptable sod along or across such areas as are designated on the drawings and in accordance with the specification requirements herein outlined.

C. Hydromulch Seeding: Seeding, followed by the application of a mulch erosion control blanket shall consist of preparing the ground, sowing of seeds, application of a fertilizer, and stabilization with mulch consisting of a biodegradable fiber along and across such areas as are designated on the plans and in accordance with these specifications

D. Silt Fence: The reinforced filter fabric barrier consists of geotextile fabric supported by a net reinforced fence stretched across and attached to supporting posts or frame and entrenched. Work shall be performed during construction operations and prior to final stabilization to control erosion and sedimentation as designated on the plans and in accordance with these specifications.

E. Inlet Protection Barriers: The inlet protection barrier consists of a geotextile fabric (filter fabric) supported by a net reinforced fence structure and constructed around a storm drain inlet, catch basin, or culvert. An alternative design of the inlet protection barrier, as approved by the Engineer, consists of fiber rolls placed around a frame, staked in place (or weighted down with clean gravel bags), and constructed around a storm drain inlet, catch basin or culvert. This work shall be performed during construction operations and prior to final stabilization to control erosion and sedimentation. As designated on the plans and in accordance with these specifications.

F. Stabilized Construction Access: This work shall consist of the installation of temporary erosion protection and sediment control stabilized construction access - type I, rock, utilized during construction operations and prior to final stabilization, in accordance with these specifications and construction drawings

4.7 QUALITY ASSURANCE

A. Codes and Standards: Install and maintain erosion control systems in compliance with all authorities having jurisdiction.

4.8 PROJECT/SITE CONDITIONS (NOT USED)

4.9 SUBMITTALS (NOT USED)

PART 5 - PRODUCTS

5.1 SUSTAINABLE MATERIALS

A. Contractor shall strive to utilize sustainable materials, which include rapidly renewable materials, regional materials, regionally manufactured materials, regionally extracted materials, recycled contents.

5.2 GRASS

A. Materials for erosion control seeding shall conform to TxDOT Item 164.

B. Materials for erosion control sodding shall conform to TxDOT Item 162.

5.3 FERTILIZER

A. Materials for fertilizing erosion control seeding and/or sodding shall conform to TxDOT Item 166.2

5.4 WATER

A. Use clean potable water for maintaining the grass developed after erosion control seeding and/or sodding. Water shall be reasonably clean and free of oil, salt, acid, alkali, sugar, vegetable matter or other substances injurious to the finished product.

B. Water sources other than the local municipal domestic water supply must be approved by the Owner.

C. If onsite reclaimed water sources are used, tanks and appurtenance must be clearly marked with the words “non-potable” water.

5.5 SILT FENCE

A. Geotextile fabric for Silt Fences must meet the TxDOT Departmental Material Specifications DMS 6230 Temporary Sediment Control Fence Fabric.

5.6 STRAW BALES

A. Standard rectangular hay bales bound by baling wire, clean and dry

5.7 INLET PROTECTION BARRIERS

A. Geotextile per 2.5 Silt Fence above.

B. Hardwood Posts shall be 2x2 minimum length 4 feet.

C. Net reinforced fence shall be 2 inch by 4 inch welded wire fabric mesh. The mesh support height shall be the equivalent height, or greater, of the geotextile fabric to be attached.

5.8 STABILIZED CONSTRUCTION ACCESS

A. Materials to be per TxDOT spec section 506.2.E.1 for Type 1

PART 6 - EXECUTION

6.1 GENERAL

A. Protection

1. Protect benchmarks, monuments, existing structures, existing fences, existing roads, existing sidewalks, existing paving, existing curbs, and other features indicated on Drawings to remain, or not indicated to be removed, from damage and displacement. If damaged or displaced, notify Engineer and correct defects as directed.

2. Protect above and below grade utilities which are to remain.

B. Preparation:

1. Use all means necessary to control dust on and near the work, and on and near off-site storage, and spoil areas, if such dust is caused by performance of the work of this Section, or if resulting from the condition in which Project Site is left by Contractor.

2. Moisten surfaces, as required, to prevent dust from being a nuisance to the public, neighbors, and concurrent performance of other work on Project Site.

C. Install erosion control systems at the site's boundary at locations where stormwater runoff will leave the site prior to starting any clearing, stripping, or earthwork operations

D. Minimize the time areas are to be exposed without vegetative cover.

E. Properly dispose of solid waste, paints, solvents, cleaning compounds, etc.

F. Store construction materials in designated areas away from drainageways and low areas.

G. Provide portable toilets and properly dispose of sanitary sewage.

H. Construct containment berms and utilize drip pans at fuel and liquid storage tanks and containers.

6.2 INSTALLATION OF EROSION CONTROL DEVICES

A. Install erosion control devices to protect adjacent and downstream properties from damage and pollution resulting from erosion caused by the work of this Contract.

1. Implement erosion control measures indicated on drawings and additional erosion control measures necessary to prevent damage to adjacent and downstream properties.

B. Install silt fence located along perimeter of site or grading limits immediately following site clearing operations specified under Division 31 Section 31 11 00 Clearing and Grubbing.

1. Install silt fence fabric from a continuous roll for the length of the silt fence whenever possible to minimize the number of joints.

a. Create joints in fabric by securely fastening fabric at the support post with overlap extending to the next post.

2. Drive support post into ground not less than 18 inches.

3. Excavate a 4 inch wide by 4 inch deep trench on up-slope side of silt fence.

a. Line trench with silt fence fabric material.

b. Backfill trench with soil or gravel.

C. Install straw bale fence at completion of grading operations in affected area as indicated on drawings.

1. Install erosion control devices at storm sewer inlets immediately after completion of the storm sewer.

2. Place straw bales in a single row, lengthwise on the contour, and embedded 4 inches into soil.

3. Secure each individual bale in place by stakes or reinforcement bars driven through bales into the ground to a depth of not less than 18 inches.

D. Install inlet protection barriers at curb inlets and at area inlets.

E. Install straw bale fences as ditch checks in drainage ditches.

F. Install Stabilized Construction Access per TxDOT specification 506.4.C.5.

6.3 EROSION CONTROL SEEDING

A. Exposed fill and stockpile areas shall be protected from windborne erosion if the phasing of the construction operations is anticipated to leave the exposed fill and stockpile areas unattended for 6 weeks or more. At completion of stockpiling operations, stockpiles shall be shaped and graded to drain. Provide a layer of mulch to all sides of the stockpile to protect the stockpile from windborne erosion.

B. Areas designated on the drawings to be seeded shall be seeded in accordance to the Texas Department of Transportation Standard Specifications, Item 164, titled "Seeding for Erosion Control". Broadcast seeding method shall be used as described in TxDOT, Item

164.4 unless otherwise instructed.

C. Areas to be seeded with slopes steeper than 10H:1V shall also utilize a soil retention blanket as specified in TxDOT Item 169 Soil Retention Blanket.

6.4 FILL AND CUT SLOPES

A. Fill slopes in all cases shall be no steeper than 3:1 unless specifically stated on the plans or approved by the Owner's Geotechnical engineer.

B. When cut slopes exceed 2:1 for depths over three (3) feet, proper bracing and shoring per OSHA requirements shall be used and maintained.

C. For permanent slopes, cut or fill, between 2:1 and 10:1, erosion protection shall be provided with hydromulch, seeding, sodding, or other method as approved.

D. Where cut slopes of more than 5 feet deep, extend more than 100 feet in length, contractor shall provide a backfill drain at the top of the slope to ease in drainage and erosion control.

6.5 MAINTENANCE

A. Check all erosion control measures after each rainfall event to ensure that they are in proper working order.

1. Immediately restore all measures to installed condition.

2. During the course of construction all temporary swales constructed for this contract shall be maintained so as to allow proper drainage from the construction area.

Before Contractor leaves the site at the end of construction, all temporary swales must be reworked to meet final conditions as set forth in the drawings and specifications.

3. The Contractor shall assure that all sub work with other contractors at the site understand the importance of the erosion control features. The Contractor shall require all subcontractors to respect the function of the erosion control features and enlist their coordination in maintaining existing swales and ditches.

B. Inspect silt and straw bale fences at least once a week.

1. Immediately replace damaged portions of the silt fences, including portions which have collapsed, contain tears, have decomposed, or have become ineffective.

2. Remove sediment deposits, as necessary, to provide adequate sediment storage and to maintain the integrity of fences. Dispose of accumulated sediment by spreading over upland areas of the site.

C. Maintain erosion control devices in place, as specified, until completion of the work of this Contract.

1. At completion of work, inspect all systems, make necessary repairs, remove and dispose of all accumulated sediment, and turn completely operable systems over to Owner for continued maintenance.

D. Where necessary for equipment and vehicular access to the work areas, adequately sized culverts shall be installed and maintained to provide the access without disturbing the site drainage.

6.6 INSPECTIONS

A. Inspect all erosion control systems and devices at least once every seven calendar days.

B. Inspect all erosion control systems and devices within 24 hours of the end of any storm which results in precipitation of 1/2 inch or more.

C. During inspections, locations where stormwater leaves the site shall be inspected for evidence of erosion or sediment deposition.

D. Correct deficiencies within three calendar days.

E. Complete a report of each inspection. Report shall contain the following minimum information:

1. Inspector's name

2. Inspection date

3. Observations of the effectiveness of erosion control systems

4. Actions taken if necessary to correct deficiencies

5. Listing of areas where construction operations have permanently or temporarily stopped

6. Authorized signature

SECTION 31 41 33

TRENCH SAFETY

PART 7 - GENERAL

A. This Section is intended to provide specifications for the minimum requirements for trench safety. The Contractor shall endeavor to insure the safety of their employees working in and around trenches and other excavations in accordance with current Occupation and Safety Health Administration (OSHA) standards and in particular, Excavations, Trenching and Shoring, Federal OSHA Standards, 29 C.F.R. part 1926, Subpart P, as amended including Final Rule, published in Federal Register Vol. 54, No. 209 Tuesday October 31, 1989 and latest amendment thereto. These specifications outline minimum standards of construction safety to be followed, but should not be construed as the means, methods and operations of construction. Where the Contractor deviates from these outlined minimum standards, the Contractor is required to submit for approval by the Owner sealed engineering plans designed by a Registered Professional Engineer in the State of Texas showing the proposed method of trench protection. A copy of the approved design shall be kept at the site.

7.2 SCOPE OF WORK

A. For all trenches in excess of five (5) feet of depth or for all trenches less than five (5) feet of depth in soils which will not stand up in vertical excavations, the Contractor shall either lay back the sides of the excavation, provide sheeting and shoring to hold the walls of the excavation in place, or use a trenching box meeting or exceeding the protection provided by the sheeting and shoring system. Trenches are defined by a horizontal width less than 15 feet. In all cases the method of trench wall protection shall be in conformance with the plans, details, and specifications or an Owner approved method designed and sealed by a Registered Professional Engineer. Owner's approval shall be permission to deviate from the specifications only and shall not be construed in any way to mean approval of the specific design, means or method of construction. The Contractor shall assume full responsibility for the system design the contractor uses, including those options presented in the contract documents and in these specifications.

7.3 RELATED WORK SPECIFIED ELSEWHERE

A. Section 31 23 33 Trenching, Backfilling and Compaction

B. Section 33 30 00 Sanitary Sewer

PART 8 - PRODUCTS

A. Materials used for sheeting, sheet piling, cribbing, bracing, shoring, underpinning, and other structural retaining systems shall be in good serviceable condition, of good quality, of a suitable condition and grade to perform the intended use. Wood shall be sound, free from large or loose knots, and of the proper dimensions. The Contractor shall be responsible for maintaining the systems in a manner consistent with the intended design and in a manner that will prevent exposure of workers to hazards.

PART 9 - EXECUTION

9.1 GENERAL SAFETY REQUIREMENTS

A. The work area shall be kept free of hazards to the employees.