SSSI Area E_Amendment 5_Rev. Specs 31 00 00_EARTHWORK.pdf

SECTION 31 00 00

EARTHWORK

08/08, CHG 6: 2/24

PART 1 GENERAL

1.1 REFERENCES

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

AMERICAN ASSOCIATION OF STATE HIGHWAY AND TRANSPORTATION OFFICIALS

(AASHTO)

AASHTO T 180 (2017) Standard Method of Test for

Moisture-Density Relations of Soils Using a 4.54-kg (10-lb) Rammer and a 457-mm (18-in.) Drop

AMERICAN WATER WORKS ASSOCIATION (AWWA)

AWWA C600 (2017) Installation of Ductile-Iron Mains and Their Appurtenances

AMERICAN WELDING SOCIETY (AWS)

AWS D1.1/D1.1M (2020) Structural Welding Code - Steel

AMERICAN WOOD PROTECTION ASSOCIATION (AWPA)

AWPA P5 (2015) Standard for Waterborne Preservatives

ASTM INTERNATIONAL (ASTM)

ASTM A139/A139M (2016) Standard Specification for

Electric-Fusion (ARC)-Welded Steel Pipe (NPS 4 and over)

ASTM A252 (2010) Standard Specification for Welded and Seamless Steel Pipe Piles

ASTM C33/C33M (2018) Standard Specification for Concrete Aggregates

ASTM C136/C136M (2019) Standard Test Method for Sieve

Analysis of Fine and Coarse Aggregates

ASTM D698 (2012; E 2014; E 2015) Laboratory Compaction Characteristics of Soil Using Standard Effort (12,400 ft-lbf/cu. ft.

(600 kN-m/cu. m.))

ASTM D1140 (2017) Standard Test Methods for Determining the Amount of Material Finer than 75-µm (No. 200) Sieve in Soils by Washing

ASTM D1556/D1556M (2015; E 2016) Standard Test Method for

Density and Unit Weight of Soil in Place by Sand-Cone Method

ASTM D1557 (2012; E 2015) Standard Test Methods for

Laboratory Compaction Characteristics of Soil Using Modified Effort (56,000 ft-lbf/ft3) (2700 kN-m/m3)

ASTM D1883 (2016) Standard Test Method for California

Bearing Ratio (CBR) of Laboratory-Compacted Soils

ASTM D2167 (2015) Density and Unit Weight of Soil in

Place by the Rubber Balloon Method

ASTM D2434 (1968; R 2006) Permeability of Granular Soils (Constant Head)

ASTM D2487 (2017; E 2020) Standard Practice for

Classification of Soils for Engineering Purposes (Unified Soil Classification System)

ASTM D2937 (2017; E 2017; E 2018) Standard Test

Method for Density of Soil in Place by the Drive-Cylinder Method

ASTM D4318 (2017; E 2018) Standard Test Methods for

Liquid Limit, Plastic Limit, and Plasticity Index of Soils

ASTM D4718/D4718M (2015) Standard Practice for Correction of

Unit Weight and Water Content for Soils Containing Oversize Particles

ASTM D6938 (2017a) Standard Test Method for In-Place

Density and Water Content of Soil and Soil-Aggregate by Nuclear Methods (Shallow Depth)

U.S. ARMY CORPS OF ENGINEERS (USACE)

EM 385-1-1 (2014) Safety and Health Requirements

Manual

U.S. ENVIRONMENTAL PROTECTION AGENCY (EPA)

EPA 600/4-79/020 (1983) Methods for Chemical Analysis of Water and Wastes

EPA SW-846.3-3 (1999, Third Edition, Update III-A) Test

Methods for Evaluating Solid Waste:

Physical/Chemical Methods

U.S. GENERAL SERVICES ADMINISTRATION (GSA)

CID A-A-203 (Rev C; Notice 3) Paper, Kraft, Untreated

1.2 DEFINITIONS

1.2.1 Satisfactory Materials

Satisfactory materials comprise any materials classified by ASTM D2487 as

GW, GP, GM, GP-GM, GW-GM, GC, GP-GC, GM-GC, SW, SP, SM, SW-SM, SC, SW-SC,

SP-SM, SP-SC, SM-SC. Satisfactory materials for grading comprise stones less than 8 inches, except for fill material for pavements and railroads which comprise stones less than 3 inches in any dimension.

Initial trench backfill should consist of select granular material or satisfactory materials free from rocks 1 inch or larger in any dimension or free from rocks of such size as recommended by the pipe manufacturer, whichever is smaller. When the pipe is coated or wrapped for corrosion protection, free the initial backfill material of stones larger than 1 inch in any dimension or as recommended by the pipe manufacturer, whichever is smaller.

1.2.2 Unsatisfactory Materials

Materials which do not comply with the requirements for satisfactory materials are unsatisfactory. Unsatisfactory materials also include man-made fills; trash; refuse; backfills from previous construction; and material classified as satisfactory which contains root and other organic matter or frozen material. Notify the Contracting Officer when encountering any contaminated materials.

1.2.3 Cohesionless and Cohesive Materials

Cohesionless materials include materials classified in ASTM D2487 as GW, GP, SW, and SP. Cohesive materials include materials classified as GC, SC, ML, CL, MH, and CH. Materials classified as GM and SM will be identified as cohesionless only when the fines are nonplastic. Perform testing, required for classifying materials, in accordance with ASTM D4318, ASTM C136/C136M and ASTM D1140.

1.2.4 Degree of Compaction

Degree of compaction required, except as noted in the second sentence, is expressed as a percentage of the maximum density obtained by the test procedure presented in ASTM D1557 abbreviated as a percent of laboratory maximum density. Since ASTM D1557 applies only to soils that have 30 percent or less by weight of their particles retained on the 3/4 inch sieve, express the degree of compaction for material having more than 30 percent by weight of their particles retained on the 3/4 inch sieve as a percentage of the maximum density in accordance with AASHTO T 180 and corrected with ASTM D4718/D4718M. To maintain the same percentage of coarse material, use the "remove and replace" procedure as described in NOTE 8 of Paragraph 7.2 in AASHTO T 180.

1.2.5 Topsoil

Material suitable for topsoils obtained from offsite areas is defined as:

Natural, friable soil representative of productive, well-drained soils in the area, free of subsoil, stumps, rocks larger than one inch diameter, brush, weeds, toxic substances, and other material detrimental to plant growth. Amend topsoil pH range to obtain a pH of 5.5 to 7. Additional requirements such as depth of the topsoil and necessary soil conditioning shall be in accordance with applicable provisions of Section 32 92 19

SEEDING.

1.2.6 Hard/Unyielding Materials

Hard/Unyielding materials comprise weathered rock, dense consolidated deposits, or conglomerate materials which are not included in the definition of "rock". These materials usually require the use of heavy excavation equipment, ripper teeth, or jack hammers for removal.

1.2.7 Rock

Solid homogeneous interlocking crystalline material with firmly cemented, laminated, or foliated masses or conglomerate deposits, neither of which can be removed without systematic drilling and blasting, drilling and the use of expansion jacks or feather wedges, or the use of backhoe-mounted pneumatic hole punchers or rock breakers; also large boulders, buried masonry, or concrete other than pavement exceeding 1/2 cubic yard in volume. Removal of hard material will not be considered rock excavation because of intermittent drilling and blasting that is performed merely to increase production.

1.2.8 Unstable Material

Unstable materials are too wet to properly support the utility pipe, conduit, or appurtenant structure.

1.2.9 Select Granular Material

Select granular material consist of materials classified as GW, GP, SW, SPor by ASTM D2487 where indicated. Select granular material shall consist of well-graded sand, gravel, crushed gravel or crushed stone composed of hard, tough and durable particles, and not more than 10 percent by weight passing a No. 200 sieve and 100 percent of material passing the 1-1/2 inch sieve when tested in accordance with ASTM D1140.

1.2.10 Initial Trench Backfill Material

Initial trench backfill consists of select granular material or satisfactory materials free from rocks one inches or larger in any dimension or free from rocks of such size as recommended by the pipe manufacturer, whichever is smaller. When the pipe is coated or wrapped for corrosion protection, free the initial backfill material of stones larger than one inches in any dimension or as recommended by the pipe manufacturer, whichever is smaller.

1.2.11 Pile Supported Structure

As used herein, a structure where both the foundation and floor slab are pile supported.

1.3 SYSTEM DESCRIPTION

Subsurface soil boring logs are provided within Appendix A - Geotechnical Assessment Report by Matrix. The subsoil investigation report and samples of materials taken from subsurface investigations are provided in the Geotechnical Assessment Report. These data represent the best subsurface information available; however, variations may exist in the subsurface between boring locations.

Soil boring logs are provided to the Contractor for information only. All interpretations of subsurface conditions, that are mentioned in the Geotechnical Assessment Report by Matrix, are not part of the project Specifications.

1.3.1 Classification of Excavation

No consideration will be given to the nature of the materials, and all excavation will be designated as unclassified excavation.

1.3.1.1 Common Excavation

Includes common excavation with the satisfactory removal and disposal of all materials not classified as rock excavation. This also includes pond materials to be excavated and disposed of off the Project Site. Excavated pond materials shall be considered contaminated and shall be handled in accordance with 02 61 13 EXCAVATION AND HANDLING OF CONTAMINATED MATERIAL.

1.3.1.2 Rock Excavation

1.3.2 Blasting

Blasting is not permitted.

1.3.3 Dewatering Work Plan

All dewatering activities must be authorized under the Umbrella SPDES Permit (NYSDEC Permit No. 2-6404-01480/00008 SPDES #NY0277070). No dewatering is to take place without an authorization from NYSDEC.

Contractor must comply with all conditions of the Umbrella SPDES permit, including required sampling during dewatering and reporting requirements. Samples must be taken after treatment to process prior to discharge to outfalls. Monitoring requirements are specified in the Umbrella SPDES permit (see page 6 of 14 of permit). The Umbrella SPDES and results of groundwater monitoring are included as attachments. Contractor to coordinate with USACE and provide Dewatering Work Plan and all other necessary information for Request for Authorization (RFA) under the Umbrella SPDES Permit to be submitted to NYSDEC by USACE.

The Dewatering Work Plan must include schematic of the treatment system, a completed "Region 2 Temporary Construction Dewatering System Detail Sheet" as attached at the end of this Section, must be submitted to USACE within 30 days of NTP, and is to be included in the SPDES Request for Authorization (RFA) submittal. The design plans must show the details of the temporary construction dewatering operation, groundwater treatment system, discharge location(s), respective existing or temporary outfall structure(s) and receiving waterbody information. If pumped and treated groundwater is to be directed to the NYCDEP sewer system, design plans must show the point(s) of discharge, identify the catch basin number(s), if applicable, and NYCDEP outfall number.

The contractor is required to design, install, and operate an appropriately sized treatment system that consists of the following physical and chemical treatment processes: sedimentation (settling), filtration, and carbon adsorption. The system must be designed to meet all effluent limitations in the Umbrella SPDES permit and the Model Technology BPJ Limits (1/98) for Carbon Adsorption included in TOGS 1.2.1 Industrial Permit Writing (see:

Attachment C-(H) Carbon Adsorption, pages 69-82, https://www.dec.ny.gov/docs/water_pdf/togs121.pdf). Changes in proposed treatment system must be submitted to USACE for approval."

1.4 SUBMITTALS

Government approval is required for submittals with a "G" or "S" classification. Submittals not having a "G" or "S" classification are for information only. When used, a code following the "G" classification identifies the office that will review the submittal for the Government.

Submit the following in accordance with Section 01 33 00 SUBMITTAL

PROCEDURES:

SD-01 Preconstruction Submittals

Shoring; G, DO

Dewatering Work Plan; G, DO

SD-03 Product Data

Utilization of Excavated Materials; G, DO

Opening of any Excavation or Borrow Pit; G, DO

Shoulder Construction

SD-06 Test Reports

Testing

Borrow Site Testing

Within 24 hours of conclusion of physical tests, submit two copies of test results, including calibration curves and results of calibration tests.

SD-07 Certificates

Testing

PART 2 PRODUCTS

http://www.dec.ny.gov/docs/water_pdf/togs121.pdf)

2.1 REQUIREMENTS FOR OFFSITE SOILS

Test offsite soils brought in for use as backfill for Total Petroleum Hydrocarbons (TPH), Benzene, Toluene, Ethyl Benzene, and Xylene (BTEX) and full Toxicity Characteristic Leaching Procedure (TCLP) including ignitability, corrosivity and reactivity. Backfill shall contain a maximum of 100 parts per million (ppm) of total petroleum hydrocarbons (TPH) and a maximum of 10 ppm of the sum of Benzene, Toluene, Ethyl Benzene, and Xylene (BTEX) and shall pass the TCPL test.

Additionally, soils brought in for use as backfill shall have concentrations less than those levels established in 6 NYCRR Part 375 for the proposed use of the Site for all chemicals for which a concentration limit is established. The most stringent of the levels established in these specifications and 6 NYCRR PART 375 shall be followed.

Determine TPH concentrations by using EPA 600/4-79/020 Method 418.1.

Determine BTEX concentrations by using EPA SW-846.3-3 Method 5030/8020.

Perform TCLP in accordance with EPA SW-846.3-3 Method 1311. Provide Borrow Site Testing for TPH, BTEX and TCLP from a composite sample of material from the borrow site, with at least one test from each borrow site. Do not bring material onsite until tests have been approved by the Contracting Officer.

2.2 BURIED WARNING AND IDENTIFICATION TAPE

Provide polyethylene plastic and metallic core or metallic-faced, acid- and alkali-resistant, polyethylene plastic warning tape manufactured specifically for warning and identification of buried utility lines.

Provide tape on rolls, 3 inches minimum width, color coded as specified below for the intended utility with warning and identification imprinted in bold black letters continuously over the entire tape length. Warning and identification to read, "CAUTION, BURIED (intended service) LINE BELOW" or similar wording. Provide permanent color and printing, unaffected by moisture or soil.

Warning Tape Color Codes

Red Electric

Yellow Gas, Oil; Dangerous Materials

Orange Telephone and Other Communications

Blue Water Systems

Green Sewer Systems

White Steam Systems

Gray Compressed Air

2.2.1 Warning Tape for Metallic Piping

Provide acid and alkali-resistant polyethylene plastic tape conforming to the width, color, and printing requirements specified above, with a minimum thickness of 0.003 inch and a minimum strength of 1500 psi lengthwise, and 1250 psi crosswise, with a maximum 350 percent elongation.

2.2.2 Detectable Warning Tape for Non-Metallic Piping

Provide polyethylene plastic tape conforming to the width, color, and printing requirements specified above, with a minimum thickness of 0.004 inch, and a minimum strength of 1500 psi lengthwise and 1250 psi crosswise. Manufacture tape with integral wires, foil backing, or other means of enabling detection by a metal detector when tape is buried up to 3 feet deep. Encase metallic element of the tape in a protective jacket or provide with other means of corrosion protection.

2.3 DETECTION WIRE FOR NON-METALLIC PIPING

Insulate a single strand, solid copper detection wire with a minimum of 12

AWG.

2.4 MATERIAL FOR RIP-RAP

Provide Bedding material, Grout, Filter fabric and rock.

2.4.1 Bedding Material

Provide bedding material consisting of sand, gravel, or crushed rock, well graded with a maximum particle size of 2 inches. Compose material of tough, durable particles. Allow no more than 10% fines passing the No. 200 standard sieve with a plasticity index less than six.

2.4.2 Grout

Provide durable grout composed of cement, water, an air-entraining admixture, and sand mixed in proportions of one part portland cement to two parts of sand, sufficient water to produce a workable mixture, and an amount of admixture which will entrain sufficient air, as determined by the Contracting Officer. Mix grout in a concrete mixer. Allow a sufficient mixing time to produce a mixture having a consistency permitting gravity flow into the interstices of the rip-rap with limited spading and brooming.

2.4.3 Rock

Provide rock fragments sufficiently durable to ensure permanence in the structure and the environment in which it is to be used. Use rock fragments free from cracks, seams, and other defects that would increase the risk of deterioration from natural causes. Provide fragments sized so that no individual fragment exceeds a weight of 150 pounds and that no more than 10 percent of the mixture, by weight, consists of fragments weighing 2 pounds or less each. Provide rock with a minimum specific gravity of 2.50 .

Do not permit the inclusion of more than trace 1 percent quantities of dirt, sand, clay, and rock fines.

2.5 CAPILLARY WATER BARRIER

Provide capillary water barrier of clean, poorly graded crushed rock, crushed gravel, or uncrushed gravel placed beneath a building slab with or without a vapor barrier to cut off the capillary flow of pore water to the area immediately below. Conform to ASTM C33/C33M for fine aggregate grading with no more than a maximum of 3 percent by weight passing ASTM D1140, No. 200 sieve, and no more than 2 percent by weight of coarse aggregate Size 57, 67, or 77.

2.6 PIPE CASING (NOT USED)

PART 3 EXECUTION

3.1 STRIPPING OF TOPSOIL

Where indicated or directed, strip topsoil to a depth of 4 inches. Spread topsoil on areas already graded and prepared for topsoil, or transported and deposited in stockpiles convenient to areas that are to receive application of the topsoil later, or at locations indicated or specified.

Keep topsoil separate from other excavated materials, brush, litter, objectionable weeds, roots, stones larger than 1 inch in diameter, and other materials that would interfere with planting and maintenance operations. Stockpile in locations indicated any surplus of topsoil from excavations and gradings.

3.2 ARCHAEOLOGICAL MONITORING

There is the potential to encounter Precontact or Historic cultural remains during the excavation for the Pond E inlet/outlet structures and associated culvert leading to the outfalls. An archaeologist will be on-site during the excavation for the inlet/outlet structures and culverts. The archaeologist will be allowed time to clear off and document, through drawings, photographs and notes, any Precontact or Historic resources encountered. The archaeological work will be undertaken by the Corps Project Archaeologist or their consultant. The construction contractor shall provide equipment and labor to mechanically excavate the area and implement all necessary safety measures.

All excavation will be limited to that required for construction in terms of location and depth. No work will be undertaken beyond these limits.

However, in areas with potential historic resources, the archaeologist can direct the excavation to be performed in a manner that avoids damage to historic resources (such as careful excavation around a buried foundation or temporarily halting excavation to examine a fill deposit).

Ideally, to facilitate the investigations this work shall be scheduled near the initiation of construction. This will allow the on-site archaeologist time to conduct their work and to address any significant resources should any be encountered. Selected locations may need to be left open over night to allow the archaeologist time to complete their work in a given area.

3.2.1 Areas of Responsibility

3.2.1.1 Contractor

The contractor shall provide equipment and operating personnel to excavate the area as defined in the construction drawings.

Contractor personnel will not be required once mechanically assisted excavation is complete and archaeologists have started their work in the open area.

The contractor shall provide and install all regulated safety measures needed to allow the on-site archaeologist to safely access the area.

The contractor shall provide equipment and operating personnel to cover the excavations at the end of the work day to uncover them at the start of the work day, as needed. It is anticipated that the excavations may need to be opened/covered on not more than 1 day at a time.

The contractor shall provide equipment and operating personnel to backfill the excavated areas at the end of the excavation, if required by COR.

3.2.1.2 Archaeologist

The on-site archaeologist(s) will be provided by the US Army Corps of Engineers and may be Corps staff (Corps Project Archaeologist) or their consultant.

The on-site archaeologist(s) shall monitor the construction excavation and shall examine and document exposed soils and archaeological features. The archaeologist can direct the excavation to be performed in a manner that avoids damage to historic resources (such as careful excavation around a buried foundation or temporarily halting excavation to examine a fill deposit).

3.2.2 Nature of the Archaeological Work

The excavation areas, locations and depths will be limited to the extent of the excavation as defined the Contract Documents. The archaeologist will be given time to safely enter the excavation area to examine the soils and features that are exposed.

The archaeologist may also conduct excavations or clearing of trenches by hand. The archaeologist may record the soil profiles and structural features in the excavated areas through photography, drawings and notes.

Cultural material, if present, may be collected and bagged appropriately for identification and curation. Limited screening of the soil removed from the excavated areas may be undertaken. The contractor will not need to be present during those times except to uncover/cover the excavation areas and install regulated safety measures, as needed.

The results of the archaeological monitoring will be presented in a written report which will be coordinated with the New York Historic Preservation Office. The report and coordination will be undertaken by the Corps Project Archaeologist.

Archeological work in any single location in which a potential historic resource is encountered is anticipated to take between 1 and 2 days.

3.2.3 Actions to be Taken by Archaeologist Should Remains Requiring Further Study be Encountered

Should significant materials or features be identified and it is determined by the Corps Project Archaeologist that further investigation of the area is required the Corps Project Archaeologist, consulting archaeologist as needed, contractor and COR shall meet to determine the level of effort and time anticipated. The Corps Project Archaeologist shall coordinate this effort with the New York Historic Preservation Office.

Delay in construction related to the need for further archaeological investigation and coordination might require a Change Order.

3.2.4 Execution

3.2.4.1 Coordination Meeting with Project Archaeologist

Prior to initiating construction, the contractor shall arrange and attend a meeting with the Corps Field Office Representative/Contract COR, Corps Project Archaeologist, consulting archaeologist as needed and other interested project parties. The purpose of this meeting, at a minimum, will be to review the following:

- Requirements and objectives of the archaeology plan.

- Archaeologist and contractor areas of responsibility.

- Authority of the archaeologist while on-site during construction.

3.2.4.2 Anticipated Excavation Requirements

As required for construction.

3.2.4.3 Possible Excavation Sequence Plan

The following identifies one possible sequencing plan for accomplishing the required archaeological work. This sequencing plan is provided for information only and may be adjusted by the Corps Project Archaeologist or contractor.

- Archaeologist could determine areas more sensitive for historic resources and suggest those areas be excavated early in construction.

- Archaeologist will be given time to examine the areas excavated;

approximately 1 day per potential historic property encountered.

Contractor can proceed with other work in the area when archaeologist is at work.

- Selected portions of the excavated area may be left open for more detailed examination and further investigations by hand. These areas may require shoring for safe entry and/or covering for safety at the end of the work day. The shoring will be installed in manner that provides safety for the archaeologist while still allowing a view to excavation unit walls.

3.3 GENERAL EXCAVATION

Perform excavation of every type of material encountered within the limits of the project to the lines, grades, and elevations indicated. and as specified. Perform the grading in accordance with the typical sections shown and the tolerances specified in paragraph FINISHING. Transport satisfactory excavated materials and place in fill or embankment within the limits of the work. Excavate unsatisfactory materials encountered within the limits of the work below grade and replace with satisfactory materials as directed. Include such excavated material and the satisfactory material ordered as replacement in excavation. Dispose surplus satisfactory excavated material not required for fill and unsatisfactory excavated material as specified in paragraph DISPOSITION OF SURPLUS MATERIAL. During construction, perform excavation and fill in a manner and sequence that will provide proper drainage at all times. If material required for fill or embankment in excess of that produced by excavation within the grading limits is required, Contractor shall submit and propose borrow areas and shall not excavate this material until reviewed and approved by the Contracting Officer.

3.3.1 Ditches, Gutters, and Channel Changes

Finish excavation of ditches, gutters, and channel changes by cutting accurately to the cross sections, grades, and elevations shown. Do not excavate ditches and gutters below grades shown. Backfill the excessive open ditch or gutter excavation with satisfactory, thoroughly compacted, material or with suitable stone or cobble to grades shown. Dispose excavated material as shown or as directed, except in no case allow material be deposited within 4 feet from edge of a ditch. Maintain excavations free from detrimental quantities of leaves, brush, sticks, trash, and other debris until final acceptance of the work.

3.3.2 Drainage Structures

Make excavations to the lines, grades, and elevations shown, or as directed. Provide trenches and foundation pits of sufficient size to permit the placement and removal of forms for the full length and width of structure footings and foundations as shown. Clean rock or other hard foundation material of loose debris and cut to a firm, level, stepped, or serrated surface. Remove loose disintegrated rock and thin strata. Do not disturb the bottom of the excavation when concrete or masonry is to be placed in an excavated area. Do not excavate to the final grade level until just before the concrete or masonry is to be placed. Where pile foundations are to be used, stop the excavation of each pit at an elevation 1 foot above the base of the footing, as specified, before piles are driven. After the pile driving has been completed, remove loose and displaced material and complete excavation, leaving a smooth, solid, undisturbed surface to receive the concrete or masonry.

3.3.3 Drainage

Provide for the collection and disposal of surface and subsurface water encountered during construction. Completely drain construction site during periods of construction to keep soil materials sufficiently dry. Construct storm drainage features (ponds/basins) at the earliest stages of site development, and throughout construction grade the construction area to provide positive surface water runoff away from the construction activity and provide temporary ditches, swales, and other drainage features and equipment as required to maintain dry soils. When unsuitable working platforms for equipment operation and unsuitable soil support for subsequent construction features develop, remove unsuitable material and provide new soil material as specified herein. It is the responsibility of the Contractor to assess the soil and ground water conditions presented by the plans and specifications and to employ necessary measures to permit construction to proceed.

3.3.4 Dewatering

Control groundwater flowing toward or into excavations to prevent sloughing of excavation slopes and walls, boils, uplift and heave in the excavation and to eliminate interference with orderly progress of construction. Do not permit French drains, sumps, ditches or trenches within 3 feet of the foundation of any structure, except with specific written approval, and after specific contractual provisions for restoration of the foundation area have been made. Take control measures by the time the excavation reaches the water level in order to maintain the integrity of the in situ material. While the excavation is open, maintain the water level continuously, at least 2 feet below the working level. Operate dewatering system continuously until construction work below existing water levels is complete. Submit performance records weekly. Measure and record performance of dewatering system at same time each day by use of observation wells or piezometers installed in conjunction with the dewatering system. Relieve hydrostatic head in previous zones below subgrade elevation in layered soils to prevent uplift.

3.3.5 Trench Excavation Requirements

Excavate the trench as recommended by the manufacturer of the pipe to be installed. Slope trench walls below the top of the pipe, or make vertical, and of such width as recommended in the manufacturer's printed installation manual. Provide vertical trench walls where no manufacturer's printed installation manual is available. Shore trench walls, cut back to a stable slope, or provide with equivalent means of protection for employees who may be exposed to moving ground or cave in, as determined by the Contractor’s Safety Engineer or other competent person; refer to USACE publication EM 385-1-1. Excavate trench walls which are cut back to at least the angle of repose of the soil. Give special attention to slopes which may be adversely affected by weather or moisture content. Do not exceed the trench width below the pipe top of 24 inches plus pipe outside diameter (O.D.) for pipes of less than 24 inches inside diameter, and do not exceed 36 inches plus pipe outside diameter for sizes larger than 24 inches inside diameter. Where recommended trench widths are exceeded, provide redesign, stronger pipe, or special installation procedures by the Contractor. The Contractor is responsible for the cost of redesign, stronger pipe, or special installation procedures without any additional cost to the Government.

3.3.5.1 Bottom Preparation

Grade the bottoms of trenches accurately to provide uniform bearing and support for the bottom quadrant of each section of the pipe. Excavate bell holes to the necessary size at each joint or coupling to eliminate point bearing. Remove stones of 2 inches or greater in any dimension, or as recommended by the pipe manufacturer, whichever is smaller, to avoid point bearing.

3.3.5.2 Removal of Unyielding Material

Where overdepth is not indicated and unyielding material is encountered in the bottom of the trench, remove such material 6 inches below the required grade and replaced with suitable materials as provided in paragraph

BACKFILLING AND COMPACTION.

3.3.5.3 Removal of Unstable Material

Where unstable material is encountered in the bottom of the trench, remove such material to the depth directed and replace it to the proper grade with select granular material as provided in paragraph BACKFILLING AND COMPACTION. When removal of unstable material is required due to the

Contractor's fault or neglect in performing the work, the Contractor is responsible for excavating the resulting material and replacing it without additional cost to the Government.

3.3.5.4 Excavation for Appurtenances

Provide excavation for manholes, catch-basins, inlets, or similar structures sufficient to leave at least 12 inches clear between the outer structure surfaces and the face of the excavation or support members.

Clean rock or loose debris and cut to a firm surface either level, stepped, or serrated, as shown or as directed. Remove loose disintegrated rock and thin strata. Specify removal of unstable material. When concrete or masonry is to be placed in an excavated area, take special care not to disturb the bottom of the excavation. Do not excavate to the final grade level until just before the concrete or masonry is to be placed.

3.3.5.5 Jacking, Boring, and Tunneling

Unless otherwise indicated, provide excavation by open cut except that sections of a trench may be jacked, bored, or tunneled if, in the opinion of the Contracting Officer, the pipe, cable, or duct can be safely and properly installed and backfill can be properly compacted in such sections.

3.3.6 Underground Utilities

The Contractor is responsible for movement of construction machinery and equipment over pipes and utilities during construction. Perform work adjacent to non-Government utilities as indicated in accordance with procedures outlined by utility company. Excavation made with power-driven equipment is not permitted within 2 feet (or more if required by the utility company) of known Government-owned utility or subsurface construction. For work immediately adjacent to or for excavations exposing a utility or other buried obstruction, excavate by hand. Start hand excavation on each side of the indicated obstruction and continue until the obstruction is uncovered or until clearance for the new grade is assured.

Support uncovered lines or other existing work affected by the contract excavation until approval for backfill is granted by the Contracting Officer. Report damage to utility lines or subsurface construction immediately to the Contracting Officer.

3.3.7 Structural Excavation

Ensure that footing subgrades have been inspected and approved by the Contracting Officer prior to concrete placement. Excavate to bottom 12-inches above pile cap prior to placing or driving piles, unless authorized otherwise by the Contracting Officer. Backfill and compact over excavations and changes in grade due to pile driving operations to 95 percent of ASTM D698 maximum density.

3.3.8 Soil Containing Phragmites

In areas where excavation activities are taking place and phragmites are present, the root mass shall be fully removed. If proposed contours indicate less than one foot of removal, then the root mass shall be over excavated to a depth of one foot, and backfilled with topsoil.

3.4 SELECTION OF BORROW MATERIAL

Select borrow material to meet the requirements and conditions of the particular fill or embankment for which it is to be used. Obtain borrow material from the borrow areas within the limits of the project site, selected by the Contractor or from approved private sources. Unless otherwise provided in the contract, the Contractor is responsible for obtaining the right to procure material, pay royalties and other charges involved, and bear the expense of developing the sources, including rights-of-way for hauling from the owners. Consider necessary clearing, grubbing, and satisfactory drainage of borrow pits and the disposal of debris thereon related operations to the borrow excavation.

3.5 OPENING AND DRAINAGE OF EXCAVATION AND BORROW PITS

Notify the Contracting Officer sufficiently in advance of the opening of any excavation or borrow pit or borrow areas to permit elevations and measurements of the undisturbed ground surface to be taken. Except as otherwise permitted, excavate borrow pits and other excavation areas providing adequate drainage. Transport overburden and other spoil material to designated spoil areas or otherwise dispose of as directed. Provide neatly trimmed and drained borrow pits after the excavation is completed.

Ensure that excavation of any area, operation of borrow pits, or dumping of spoil material results in minimum detrimental effects on natural environmental conditions.

3.6 SHORING

3.6.1 General Requirements

Submit a Shoring and Sheeting plan for approval 15 days prior to starting work. Submit drawings and calculations, certified by a State of New York registered professional engineer, describing the methods for shoring and sheeting of excavations. Finish shoring, including sheet piling, and install as necessary to protect workmen, banks, adjacent paving, structures, and utilities. Remove shoring, bracing, and sheeting as excavations are backfilled, in a manner to prevent caving.

3.6.2 Geotechnical Engineer

The Contractor must hire a State of New York registered Professional Geotechnical Engineer to provide inspection of excavations and soil/groundwater conditions throughout construction. The Geotechnical Engineer is responsible for performing pre-construction and periodic site visits throughout construction to assess site conditions. The Geotechnical Engineer is responsible for updating the excavation, sheeting and dewatering plans as construction progresses to reflect changing conditions and submit an updated plan if necessary. Submit a monthly written report, informing the Contractor and Contracting Officer of the status of the plan and an accounting of the Contractor's adherence to the plan addressing any present or potential problems. The Contracting Officer is responsible for arranging meetings with the Geotechnical Engineer at any time throughout the contract duration.

3.7 GRADING AREAS

Where indicated, divide work into grading areas within which satisfactory excavated material will be placed in embankments, fills, and required backfills. Do not haul satisfactory material excavated in one grading area to another grading area except when so directed in writing. Place and grade stockpiles of satisfactory and unsatisfactory materials as specified. Keep stockpiles in a neat and well drained condition, giving due consideration to drainage at all times. Clear, grub, and seal by rubber-tired equipment, the ground surface at stockpile locations;

separately stockpile excavated satisfactory and unsatisfactory materials.

Protect stockpiles of satisfactory materials from contamination which may destroy the quality and fitness of the stockpiled material. If the Contractor fails to protect the stockpiles, and any material becomes unsatisfactory, remove and replace such material with satisfactory material from approved sources.

3.8 FINAL GRADE OF SURFACES TO SUPPORT CONCRETE

Do not excavate to final grade until just before concrete is to be placed.

For pile foundations, stop the excavation at an elevation of from 6 to 12 inches above the bottom of the footing before driving piles. After pile driving has been completed, complete the remainder of the excavation to the elevations shown. Roughen the level surfaces, and cut the sloped surfaces, as indicated, into rough steps or benches to provide a satisfactory bond.

Protect surfaces from erosion resulting from ponding or water flow.

3.9 GROUND SURFACE PREPARATION

3.9.1 General Requirements

Remove and replace unsatisfactory material with satisfactory materials, as directed by the Contracting Officer, in surfaces to receive fill or in excavated areas. Scarify the surface to a depth of 6 inches before the fill is started. Plow, step, bench, or break up sloped surfaces steeper than 1 vertical to 4 horizontal so that the fill material will bond with the existing material. When subgrades are less than the specified density, break up the ground surface to a minimum depth of 6 inches, pulverizing, and compacting to the specified density. When the subgrade is part fill and part excavation or natural ground, scarify the excavated or natural ground portion to a depth of 12 inches and compact it as specified for the adjacent fill.

3.9.2 Frozen Material

Do not place material on surfaces that are muddy, frozen, or contain frost. Finish compaction by sheepsfoot rollers, pneumatic-tired rollers, steel-wheeled rollers, or other approved equipment well suited to the soil being compacted. Moisten material as necessary to plus or minus 2 percent of optimum moisture .

3.10 UTILIZATION OF EXCAVATED MATERIALS

Use satisfactory material removed from excavations, insofar as practicable, in the construction of fills, embankments, subgrades, shoulders, bedding (as backfill), and for similar purposes. Submit procedure and location for disposal of unused satisfactory material. Dispose surplus satisfactory excavated material not required for fill and unsatisfactory excavated material as specified in paragraph DISPOSITION OF SURPLUS MATERIAL.

Stockpile and use coarse rock from excavations for constructing slopes or embankments adjacent to streams, or sides and bottoms of channels and for protecting against erosion. Do not dispose excavated material to obstruct the flow of any stream, endanger a partly finished structure, impair the efficiency or appearance of any structure, or be detrimental to the completed work in any way.

3.11 BURIED TAPE AND DETECTION WIRE

3.11.1 Buried Warning and Identification Tape

Provide buried utility lines with utility identification tape. Bury tape 12 inches below finished grade; under pavements and slabs, bury tape 6 inches below top of subgrade.

3.11.2 Buried Detection Wire

Bury detection wire directly above non-metallic piping at a distance not to exceed 12 inches above the top of pipe. Extend the wire continuously and unbroken, from manhole to manhole. Terminate the ends of the wire inside the manholes at each end of the pipe, with a minimum of 3 feet of wire, coiled, remaining accessible in each manhole. Furnish insulated wire over its entire length. Install wires at manholes between the top of the corbel and the frame, and extend up through the chimney seal between the frame and the chimney seal. For force mains, terminate the wire in the valve pit at the pump station end of the pipe.

3.12 FILLING, BACKFILLING AND COMPACTION

Place fill and backfill beneath and adjacent to any and all type of structures, in successive horizontal layers of loose material not more than 8 inches in depth, or in loose layers not more than 5 inches in depth when using hand-operated compaction equipment. Compact to at least 90 percent of laboratory maximum density for cohesive materials or 95 percent of laboratory maximum density for cohesionless materials, except as otherwise specified. Perform compaction in such a manner as to prevent wedging action or eccentric loading upon or against the structure. Moisture condition fill and backfill material to within range of +2 or -2 percent of optimum moisture content at the time of compaction.

Prepare ground surface on which backfill is to be placed and provide compaction requirements for backfill materials in conformance with the applicable portions of paragraphs GROUND SURFACE PREPARATION. Finish compaction by sheepsfoot rollers, pneumatic-tired rollers, steel-wheeled rollers, vibratory compactors, or other approved equipment.

3.12.1 Trench Backfill

Backfill trenches to the grade shown. Backfill the trench to 1 foot above the top of pipe prior to performing the required pressure tests. Leave the joints and couplings uncovered during the pressure test. Do not complete backfill of the trench until all specified tests are performed.

3.12.1.1 Replacement of Unyielding Material

Replace unyielding material removed from the bottom of the trench with select granular material or initial backfill material.

3.12.1.2 Replacement of Unstable Material

Replace unstable material removed from the bottom of the trench or excavation with select granular material placed in layers not exceeding 6 inches loose thickness.

3.12.1.3 Bedding and Initial Backfill

Except as specified otherwise in the individual piping section, provide bedding for buried piping in accordance with AWWA C600, Type 4, except as specified herein. Backfill to top of pipe shall be compacted to 95 percent of ASTM D698 maximum density. Plastic piping shall have for testing initial portion of pipe, the bedding installed to spring line of pipe. Provide ASTM D2321 materials as follows:

a. Class I: Angular, 0.25 to 1.5 inches, graded stone, including a number of fill materials that have regional significance such as coral, slag, cinders, crushed stone, and crushed shells.

b. Class II: Coarse sands and gravels with maximum particle size of 1.5 inches, including various graded sands and gravels containing small percentages of fines, generally granular and noncohesive, either wet or dry. Soil Types GW, GP, SW, and SP are included in this class as specified in ASTM D2487 for bedding as indicated.

c. Class III Clean, coarse-grained well graded natural gravel, crushed stone or a combination thereof identified as gravel in accordance with Section 31 23 00.00 20 EXCAVATION AND FILL, gradation having a classification of GW and GP in accordance with ASTM D2487 for bedding and backfill as indicated. Do not exceed maximum particle size of 1.5 inches.

3.12.1.3.1 Sand

Clean, coarse-grained sand classified as SW or SP in accordance with Section 31 23 00.00 20 EXCAVATION AND FILL, or SW or SP by ASTM D2487 for bedding and backfill as indicated.

3.12.1.3.2 Gravel and Crushed Stone

Clean, coarsely graded natural gravel, crushed stone or a combination thereof identified as GW or GP in accordance with Section 31 23 00.00 20 EXCAVATION AND FILL, or having a classification of GW or GP in accordance with ASTM D2487 for bedding and backfill as indicated. Do not exceed maximum particle size of 3 inches.

3.12.1.4 Final Backfill

Fill the remainder of the trench, except for special materials for roadways, with satisfactory material. Place backfill material and compact as follows:

3.12.1.4.1 Roadways

Place backfill up to the required elevation as specified. Do not permit water flooding or jetting methods of compaction.

3.12.1.4.2 Sidewalks, Turfed or Seeded Areas and Miscellaneous Areas

Deposit backfill in layers of a maximum of 12 inches loose thickness, and compact it to 85 percent maximum density for cohesive soils and 90 percent maximum density for cohesionless soils. Do not permit compaction by water flooding or jetting. Apply this requirement to all other areas not specifically designated above.

3.12.2 Backfill for Appurtenances

After the manhole, catch basin, inlet, or similar structure has been constructed and the concrete has been allowed to cure for 14 days, place backfill in such a manner that the structure is not be damaged by the shock of falling earth. Deposit the backfill material, compact it as specified for final backfill, and bring up the backfill evenly on all sides of the structure to prevent eccentric loading and excessive stress.

3.13 SPECIAL REQUIREMENTS

Special requirements for both excavation and backfill relating to the specific utilities are as follows:

3.13.1 Gas Distribution

Excavate trenches to a depth that will provide a minimum 18 inches of cover in rock excavation and a minimum 24 inch of cover in other excavation.

3.13.2 Water Lines

Excavate trenches to a depth that provides a minimum cover of 4.5 feet from the existing ground surface, or from the indicated finished grade, whichever is lower, to the top of the pipe. For fire protection yard mains or piping, an additional 6 inches of cover is required.

3.13.3 Heat Distribution System

Free initial backfill material of stones larger than 1/4 inch in any dimension.

3.13.4 Electrical Distribution System

Provide a minimum cover of 24 inches from the finished grade to direct burial cable and conduit or duct line, unless otherwise indicated.

3.13.5 Sewage Absorption Trenches or Pits (NOT USED)

3.13.6 Pipeline Casing (NOT USED)

3.13.6.1 Bore Holes (NOT USED)

3.13.6.2 Cleaning (NOT USED)

3.13.6.3 End Seals (NOT USED)

3.13.7 Rip-Rap Construction

Construct rip-rap in accordance with Section 70.71 of the NYCDEP Standard Sewer and Water Main Specifications. Trim and dress indicated areas to conform to cross sections, lines and grades shown within a tolerance of

0.1 foot.

3.13.7.1 Bedding Placement

Spread filter fabric bedding material uniformly to a thickness of at least 3 inches on prepared subgrade as indicated.

3.13.7.2 Stone Placement (NOT USED)

3.13.7.3 Grouting (NOT USED)

3.14 EMBANKMENTS

3.14.1 Earth Embankments

Construct earth embankments from satisfactory materials free of organic or frozen material and rocks with any dimension greater than 3 inches. Place the material in successive horizontal layers of loose material not more than 8 inches in depth. Spread each layer uniformly on a soil surface that has been moistened or aerated as necessary, and scarified or otherwise broken up so that the fill will bond with the surface on which it is placed.

After spreading, plow, disk, or otherwise break up each layer; moisten or aerate as necessary; thoroughly mix; and compact to at least 90 percent laboratory maximum density for cohesive materials or 95 percent laboratory maximum density for cohesionless materials as determined by ASTM D1557.

Backfill and fill material must be within the range of -2 to +2 percent of optimum moisture .

Compaction requirements for the upper portion of earth embankments forming subgrade for pavements are identical with those requirements specified in paragraph SUBGRADE PREPARATION. Finish compaction by sheepsfoot rollers, pneumatic-tired rollers, steel-wheeled rollers, vibratory compactors, or other approved equipment.

3.14.2 Rock Embankments (NOT USED)

3.15 SUBGRADE PREPARATION

3.15.1 Proof Rolling

Finish proof rolling on an exposed subgrade free of surface water (wet conditions resulting from rainfall) which would promote degradation of an otherwise acceptable subgrade.

3.15.2 Construction

Shape subgrade to line, grade, and cross section, and compact as specified. Include plowing, disking, and any moistening or aerating required to obtain specified compaction for this operation.

3.15.3 Compaction

Finish compaction by…