31 00 00 Earthwork.pdf

Pine Hollow Stream Removal Project Allegheny County, PA

Section 31 00 00 Page 1

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Revised by Amendment 0001

SECTION 31 00 00

EARTHWORK

PART 1 GENERAL

1.1 APPLICABLE PUBLICATION

(PADOT) Pennsylvania Department of Transportation Standard Publication 408, Highway Construction Specifications, most recent and all revisions thereof and amendments to.

1.2 MEASUREMENT PROCEDURES

1.2.1 Class 1B Excavation

The unit of measurement for excavation will be the cubic yard, computed by the average end area method from measurements taken before and after the excavation operations. The measurements will include authorized excavation of existing pavement that has been saw cut to neat defined limits. The measurement will not include the volume of subgrade material or other material that is scarified or plowed and reused in-place, and will not include the volume excavated without authorization or the volume of any material used for purposes other than directed. The measurement will not include the volume of any excavation performed prior to the taking of elevations and measurements of the undisturbed grade. See Section 01 22

00.00 10 MEASUREMENT AND PAYMENT.

1.2.2 Class 4 Excavation (Piping Trench and Structure Excavation)

Measure trench excavation by the number of linear feet along the centerline of the trench and excavate to the depths and widths specified for the particular size of pipe. Replace unstable trench bottoms with a selected granular material. Include the additional width at manholes and similar structures, the furnishing, placing and removal of sheeting and bracing, pumping and bailing, and all incidentals necessary to complete the work required by this section. See Section 01 22 00.00 10 MEASUREMENT AND PAYMENT. Pay lines for trench excavation are the trench and structure pay limits as shown on the drawings. Measurement of excavation shall be made on the basis of the actual volume of material excavated within the pay limit of the trench or structure as indicated on the drawings. No measurement will be made of excavation outside the pay limits shown unless otherwise approved by the Contracting Officer.

1.2.3 Rock Excavation

Measure and pay for rock excavation by the number of cubic yards of acceptably excavated rock material. Measure the material in place, but base volume on a maximum 30 inch width for pipes 12 inch in diameter or less, and a maximum width of 24 inch greater than the outside diameter of the pipe for pipes over 12 inch in diameter. Provide the measurement to include all authorized overdepth rock excavation as determined by the Contracting Officer. For manholes and other appurtenances, compute volumes of rock

Section 31 00 00 Page 2

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Revised by Amendment 0001 excavation on the basis of 1 foot outside of the wall lines of the structures. See Section 01 22 00.00 10 MEASUREMENT AND PAYMENT.

1.2.4 Topsoil Requirements

Excavation, hauling, and spreading or piling of topsoil and related miscellaneous operations will be considered subsidiary obligations of the Contractor, covered under the contract unit price for Class 1 Excavation.

See Section 01 22 00.00 10 MEASUREMENT AND PAYMENT.

1.2.5 Select Granular Material

Measure select granular material in place as the actual cubic yards replacing wet or unstable material in trench bottoms within the limits shown. Provide unit prices which include furnishing and placing the granular material, excavation and disposal of unsatisfactory material, and additional requirements for sheeting and bracing, pumping, bailing, cleaning, and other incidentals necessary to complete the work. See Section

01 22 00.00 10 MEASUREMENT AND PAYMENT.

1.3 PAYMENT PROCEDURES

Payment will constitute full compensation for all labor, equipment, tools, supplies, and incidentals necessary to complete the work. See Section 01 22

00.00 10 MEASUREMENT AND PAYMENT.

1.3.1 Class 1B Excavation

Classified excavation will be paid for at the contract unit prices per cubic yard for pavement excavation. See Section 01 22 00.00 10 MEASUREMENT AND

PAYMENT.

1.3.2 Class 4 Excavation

Payment for trench excavation will constitute full payment for excavation and backfilling, including specified overdepth except in rock or unstable trench bottoms. See Section 01 22 00.00 10 MEASUREMENT AND PAYMENT.

1.3.3 Rock Excavation

Payment for rock excavation will be made in addition to the price bid for the trench excavation, and will include all necessary drilling wedging, sledging, barring or braking with power operated tools and all incidentals necessary to excavate and dispose of the rock. Select granular material, used as backfill replacing rock excavation, will not be paid for separately, but will be included in the unit price for rock excavation. See Section 01

22 00.00 10 MEASUREMENT AND PAYMENT.

1.4 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.

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AMERICAN ASSOCIATION OF STATE HIGHWAY AND TRANSPORTATION OFFICIALS

(AASHTO)

AASHTO T 180 (2009) Moisture-Density Relations of Soils

Using a 4.54-kg (10-lb) Rammer and an 457-mm (18-in) Drop

AASHTO T 224 (2001; R 2004) Correction for Coarse

Particles in the Soil Compaction Test

AMERICAN WATER WORKS ASSOCIATION (AWWA)

AWWA C600 (2005) Installation of Ductile-Iron Water

Mains and Their Appurtenances

ASTM INTERNATIONAL (ASTM)

ASTM A 139/A 139M (2004) Standard Specification for Electric-

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

ASTM A 252 (1998; R 2007) Standard Specification for

Welded and Seamless Steel Pipe Piles

ASTM C 136 (2006) Standard Test Method for Sieve

Analysis of Fine and Coarse Aggregates

ASTM C 33/C 33M (2008) Standard Specification for Concrete

Aggregates

ASTM D 1140 (2000; R 2006) Amount of Material in Soils

Finer than the No. 200 (75-micrometer) Sieve

ASTM D 1556 (2007) Density and Unit Weight of Soil in

Place by the Sand-Cone Method

ASTM D 1557 (2007) Standard Test Methods for Laboratory

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

ASTM D 1883 (2007e1e2) CBR (California Bearing Ratio) of

Laboratory-Compacted Soils

ASTM D 2167 (2008) Density and Unit Weight of Soil in

Place by the Rubber Balloon Method

ASTM D 2487 (2006e1) Soils for Engineering Purposes

(Unified Soil Classification System)

ASTM D 2937 (2004) Density of Soil in Place by the Drive-

Cylinder Method

ASTM D 422 (1963; R 2007) Particle-Size Analysis of

Soils

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ASTM D 4318 (2005) Liquid Limit, Plastic Limit, and Plasticity Index of Soils

ASTM D 6938 (2007a) Standard Test Method for In-Place

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

ASTM D 698 (2007e1) Laboratory Compaction

Characteristics of Soil Using Standard Effort (12,400 ft-lbf/cu. ft. (600 kN-m/cu. m.))

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

1.5 DEFINITIONS

1.5.1 Representative

Reference to "Representative" within the Pennsylvania Department of Transportation Standard Specifications for Road and Bridge Construction shall be interpreted to mean "Contracting Officer".

1.5.2 Department

Reference to "Department" within the Pennsylvania Department of Transportation Standard Specifications for Road and Bridge Construction shall be interpreted to mean "Government".

1.5.3 Satisfactory Materials

Satisfactory materials comprise any materials classified by ASTM D 2487 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, CL, ML, CL-ML, CH, MH. 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.

1.5.4 Unsatisfactory Materials

Materials which do not comply with the requirements for satisfactory materials are unsatisfactory. Unsatisfactory materials also include man-made fills (unless comprised of materials listed in section 1.5.3); trash;

refuse; backfills from previous construction (unless comprised of materials listed in section 1.5.3); and material classified as satisfactory which contains root and other organic matter or frozen material. Notify the Contracting Officer when encountering any contaminated materials.

1.5.5 Cohesionless and Cohesive Materials

Cohesionless materials include materials classified in ASTM D 2487 as GW, GP, SW, and SP. Cohesive materials include materials classified as GC, SC, Section 31 00 00 Page 5

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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 D 4318, ASTM C 136, ASTM D 422, and ASTM D 1140.

1.5.6 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 D 698 abbreviated as a percent of laboratory maximum density. Since ASTM D 698 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 AASHTO T 224. 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.

1.5.7 Topsoil

Material suitable for topsoils obtained from offsite areas and excavations 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.

1.5.8 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, wedging, sledging, barring or braking with power operated tools 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.

1.5.9 Unstable Material

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

1.5.10 Select Granular Material

1.5.10.1 General Requirements

Select granular materials consist of materials classified as GW, GP, SW,or SP, by ASTM D 2487 where indicated.

1.5.10.2 Initial Backfill Material

Initial backfill consists of crushed stone conforming to PADOT 2A material, as designated in PADOT Publication 408 or AASHTO No. 57 aggregate.

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1.5.11 Nonfrost Susceptible (NFS) Material

Nonfrost susceptible material are a uniformly graded washed sand with a maximum particle size of .25 inch and less than 5 percent passing the No.

200 size sieve, and with not more than 3 percent by weight finer than 0.02 mm grain size.

1.6 SYSTEM DESCRIPTION

Subsurface soil boring logs are shown on in the Geotechnical Engineering Report prepared by RHEA Engineering. The report is considered a part of these specifications.

1.6.1 Classification of Excavation

Finish the specified excavation on a classified basis, in accordance with the following designations and classifications.

1.6.1.1 Class 1B Excavation

Include common excavation with the satisfactory removal and disposal of all materials classified as pavement.

1.6.1.2 Class 4 Excavation

Include common excavation with the satisfactory removal and disposal of all materials not classified as pavement or rock excavation for trench excavations.

1.6.1.3 Rock Excavation

Include rock excavation with excavating, grading, disposing of material classified as rock, and the satisfactory removal and disposal of boulders 1/2 cubic yard or more in volume; solid rock; rock material that is in ledges, bedded deposits, and unstratified masses, which cannot be removed without systematic drilling wedging, sledging, barring or braking with power operated tools; firmly cemented conglomerate deposits possessing the characteristics of solid rock impossible to remove without systematic drilling wedging, sledging, barring or braking with power operated tools;

and hard materials (see Definitions). Include the removal of any concrete or masonry structures, except pavements, exceeding 1/2 cubic yard in volume that may be encountered in the work in this classification. If at any time during excavation, the Contractor encounters material that may be classified as rock excavation, uncover such material and notify the Contracting Officer. Do not proceed with the excavation of this material until the Contracting Officer has classified the materials as common excavation or rock excavation and has taken cross sections as required.

Failure on the part of the Contractor to uncover such material, notify the Contracting Officer, and allow ample time for classification and cross sectioning of the undisturbed surface of such material will cause the forfeiture of the Contractor's right of claim to any classification or volume of material to be paid for other than that allowed by the Contracting Officer for the areas of work in which such deposits occur.

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1.6.2 Blasting

Blasting is not permitted for work under this contract.

1.6.3 Dewatering Work Plan

Submit procedures for accomplishing dewatering work.

1.7 SUBMITTALS

Government approval is required for submittals with a "G" designation;

submittals not having a "G" designation are for Contractor Quality Control approval. Submit the following in accordance with Section 01 33 00

SUBMITTAL PROCEDURES:

SD-01 Preconstruction Submittals

Shoring; G

Dewatering Work Plan; G

SD-03 Product Data

Utilization of Excavated Materials; G] Rock Excavation Opening of any Excavation or Borrow Pit Shoulder Construction Provide the following; procedure and location for disposal of unused satisfactory material; notification of encountering rock in the project; advance notice on the opening of excavation;

advance notice on shoulder construction for rigid pavements.

SD-06 Test Reports

Testing Borrow Site Testing Within 24 hours of conclusion of physical tests, 6 copies of test results, including calibration curves and results of calibration tests. Results of testing at the borrow site.

SD-07 Certificates

Testing Qualifications of the validated commercial testing laboratory or the Contractor's validated testing facilities.

PART 2 PRODUCTS

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. Determine TPH concentrations by using

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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 inch 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 4 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

Rock conforming to (PADOT) Publication 408, Section 850, ROCK LINING, Class R-6.

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2.4.1 Geotextile

Provide Filter fabric in accordance with Section 31 05 19 GEOTEXTILE.

2.4.2 Bedding Material

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

2.4.3 Sheeting and Piling Planks

All planks used for sheeting and sheet piling and all timber used for braces, shores and stringers or waling strips shall be sound, straight grained yellow pine, douglas fir or other material of equal or greater strength. All plank and timber shall be free from cracks, shakes and large or loose knots. Planks shall be tongued and grooved or grooved and splinted if so required. Steel sheeting, if used, shall be the standard and generally accepted product of a recognized manufacturer. All materials used in work covered by this Section of the Specifications shall conform to the current regulations of OSHA and the Pennsylvania Department of Labor and Industry for excavations and construction and shall be at least equal to the dimensions set forth therein.

2.4.4 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.

PART 3 EXECUTION

3.1 STRIPPING OF TOPSOIL

Where indicated or directed, strip topsoil to a depth of 4 to 6 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 2 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 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 tolerances specified in paragraph 3.13 FINISHING. Transport satisfactory excavated materials and

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Revised by Amendment 0001 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 or embankment in areas approved for surplus material storage or designated waste areas. Dispose unsatisfactory excavated material in designated waste or spoil areas. During construction, perform excavation and fill in a manner and sequence that will provide proper drainage at all times. Excavate material required for fill or embankment in excess of that produced by excavation within the grading limits from other approved areas selected by the Contractor as specified.

3.2.1 Ditches, Gutters, and Channel Changes

Finish excavation of ditches, gutters, and channel changes by cutting accurately as shown in the Construction Drawings. 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 a maximum 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.

3.2.2 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.

3.2.3 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/or 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.

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3.2.4 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, to keep the working level free of water. Excavations shall be kept dry and free of water. Discharge of precipitation and subsurface water must clear the immediate work site area. The Contractor shall maintain the pipe trenches dry until the piping has been jointed, inspected, and backfilled, and concrete work has been completed. Trench water shall be prevented from entering pipelines under construction. The Contractor shall intercept and divert surface drainage away from excavations. Surface drainage systems shall be conducted in such a manner that they do not cause erosion on or off the site, or cause the unwanted flow of water. The Contractor shall comply with Federal and State requirements for dewatering to any watercourse, prevention of stream degradation, and erosion and sediment control. Relieve hydrostatic head in pervious zones below subgrade elevation in layered soils to prevent uplift.

3.2.5 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 5 feet or more than in vertical height, shall be 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. Shore vertical trench walls more than 5 feet high.

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 inch inside diameter, and do not exceed 36 inch plus pipe outside diameter for sizes larger than 24 inch 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.

Trench excavation shall be in strict conformance with OSHA Regulations regarding the selection of (1) sloping and benching systems, and/or (2) support, shield or other systems. A Registered Professional Engineers certified design calculation will be required for protective systems where trench depth is greater than 20 feet, in accordance with paragraphs 1926.652

(b) and (c) of the Regulations. In addition, a Professional Engineers certification and usage specification for trench shoring/shielding system or sloping of trenches will be required where the trench depth is 20 feet or less in accordance with Subpart B of the Regulations. The Professional Engineer must be registered in the Commonwealth of Pennsylvania.

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3.2.5.1 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 inch or greater in any dimension, or as recommended by the pipe manufacturer, whichever is smaller, to avoid point bearing.

3.2.5.2 Removal of Unyielding Material

Where unyielding materials is encountered in the bottom of the trench, remove such material 6 inch below the required grade and replaced with suitable materials as provided in paragraph BACKFILLING AND COMPACTION.

3.2.5.3 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.

3.2.5.4 Excavation for Appurtenances

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

3.2.5.5 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.

3.2.6 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. The Contractor shall report damage to utility lines or subsurface construction immediately to the Contracting Officer.

3.2.7 Structural Excavation

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Ensure that footing subgrades have been inspected and approved by the Contracting Officer prior to concrete placement.

3.2.8 Exploratory Excavation and Backfill

The Contractor shall excavate exploratory test pits at locations of potential conflict between existing and proposed facilities, or as directed.

Notify appropriate utility companies three days in advance of test pit excavation to coordinate this work with the company. After placing maintenance and protection of traffic signing and securing the working areas, immediately excavate test pits within the approved work areas to provide maximum lead-time for necessary design changes or public utility owner changes. Tie locations of utilities or underground structures to construction base lines and Project elevations. Record and report data and furnish copies to the Contracting Officer. Furnish, place, and remove bracing, shoring and incidental materials if required. Where water is encountered, bail and/or pump as necessary.

When necessary, backfill test pits with materials approved by the Contracting Officer, compact, and cover with temporary bituminous pavement or concrete base course as directed.

Anticipate that the data on horizontal and vertical locations of existing underground structures or utilities from test pit excavation will result in modification of the Drawings and locations of underground facilities by the Contracting Officer. Begin no installation without the Contracting Officer's approval. Evaluate test pit information and any other data to anticipate conflicts with storm or sanitary sewer to preclude false trenching starts.

3.2.9 Removal of Manmade Objects

Removal of Authority facilities (waterlines, sewers, ect.) is considered to be incidental to other excavation, except where otherwise defined. Removal of other manmade objects greater than one-third of a cubic yard in volume will be performed as Rock Excavation or on a time-and-materials basis, as defined in the pay items for the project.

3.2.10 Rock Excavation

The word "rock", in this context, shall mean boulders and pieces of concrete or masonry exceeding 1/3 cubic yards in volume; or solid ledge rock which (in the opinion of the Contraction Officer) require for its removal wedging, sledging, barring or breaking up with power-operated tools.

The following are not classified as rock and their removal will not be compensated as such, unless specifically noted:

- Soft or disintegrated rock which can be removed with a hand pick or power-operated excavator or shovel.

- Loose, shaken or broken stone in rock fillings or elsewhere

- Frozen earth or existing paving

- Rock exterior to the maximum limits of measurement allowed, which may fall into the excavation.

The Contractor shall excavate rock (as defined above), if encountered, to the lines and grades indicated on the Plans or as required herein and

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Revised by Amendment 0001 dispose of the excavated material. Rock in pipe trenches shall be excavated to the extent required so as to be not less than 6" from the invert of the pipe, or as shown on the drawings. Rock in structure excavations shall be excavated to the bottom of the foundation.

3.3 OPENING AND DRAINAGE OF EXCAVATION

Notify the Contracting Officer sufficiently in advance of the opening of any excavation or borrow pit to permit elevations and measurements of the undisturbed ground surface to be taken. Except as otherwise permitted, excavate all areas to provide adequate drainage during all phases of construction. Transport overburden and other spoil material to designated spoil areas or otherwise dispose of as directed. Ensure that excavation of any area, or dumping of spoil material results in minimum detrimental effects on natural environmental conditions.

3.4 SHORING

3.4.1 General Requirements

Submit a Shoring and Sheeting plan for approval 15 days prior to starting work. Submit drawings and calculations, certified by a 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.

3.4.2 Geotechnical Engineer

Hire a 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 isContractor shall be responsible for arranging meetings with the Contracting Officer and the Geotechnical Engineer at any time throughout the contract duration.

3.5 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 materials as specified. The Contractor shall 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

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Revised by Amendment 0001 to protect the stockpiles, and any material becomes unsatisfactory, remove and replace such material with satisfactory material from approved sources.

3.6 GROUND SURFACE PREPARATION

3.6.1 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 inch 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 inch, 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 inch and compact it as specified for the adjacent fill.

3.6.2 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.

3.7 UTILIZATION OF EXCAVATED MATERIALS

Dispose of unsatisfactory materials and surplus satisfactory materials to a state licensed landfill site. Use satisfactory material removed from excavations, insofar as practicable, in the construction of fills, embankments, subgrades, shoulders, bedding (as backfill), and for similar purposes. Do not waste any satisfactory excavated material without specific written authorization. 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.

3.8 BURIED TAPE AND DETECTION WIRE

3.8.1 Buried Warning and Identification Tape

Provide buried utility lines with utility identification tape. Buried tape shall be laid between backfilling lifts over the pipe not less than two feet above the pipe not less than two feet below the finished ground surface. In no event shall the tape be more than four feet below the finished ground surface.

3.9 BACKFILLING AND COMPACTION

Place backfill adjacent to any and all types of structures, and compact in accordance with the recommendations provided by the Geotechnical Engineering Report as prepared by RHEA Engineering. Prepare ground surface on which backfill is to be placed as specified in paragraph 3.6GROUND SURFACE PREPARATION. Provide compaction requirements for backfill materials in

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Revised by Amendment 0001 conformance with the applicable portions of paragraphs 3.6 GROUND SURFACE PREPARATION. Finish compaction by sheepsfoot rollers, pneumatic-tired rollers, steel-wheeled rollers, vibratory compactors, or other approved equipment.

3.9.1 Trench Backfill

Backfill trenches to the grade shown. Leave the joints and couplings uncovered during the pressure test. Do not backfill the trench until all specified tests are performed. Suitable backfill material shall be in accordance with materials called for according to the specific conditions defined below.

3.9.1.1 Replacement of Unyielding Material

Replace unyielding material removed from the bottom of the trench with No 2A Coarse Aggregate or No. 57 Stone in accordance with (PADOT) Publication 408 Section 703.2.

3.9.1.2 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 inch loose thickness.

3.9.1.3 Bedding and Initial Backfill

Provide bedding of the type and thickness shown on the drawings. Place initial backfill material and compact it with approved tampers to a height of at least one foot above the utility pipe or conduit. Bring up the backfill evenly on both sides of the pipe for the full length of the pipe.

Take care to ensure thorough compaction of the fill under the haunches of the pipe. 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. The Contractor shall compact backfill to top of pipe to 95 percent of ASTM D 698 maximum density. Provide plastic piping with bedding to spring line of pipe. Provide materials as follows:

Bedding material of AASHTO No. 67 aggregate, No. 57 aggregate, or No. 2A, crushed limestone aggregate, Table C, Section 703.2, PennDOT Publication 408 Specifications, shall be utilized. See the Construction Details. Materials not acceptable as bedding includes sharp edged aggregate, earth, wet granulated slag and open hearth slag.

Suitable Backfill Material (Street Areas):

a. Crushed stone or gravel aggregate conforming to No 2A Coarse Aggregate in accordance with (PADOT) Publication 408, Section 703.2.

Suitable Backfill Material (Other than Street Areas):

b. Material excavated from the trench if free of stones larger than 2" in size and free of wet, frozen or organic material and conforming to (PADOT) Publication 408, Section 206.2.

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3.9.1.4 Final Backfill

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

a. Roadways and Sidewalks: Place Crushed stone or gravel aggregate conforming to No 2A Coarse Aggregate in accordance with (PADOT) Publication 408, Section 703.2 backfill up to the required elevation as specified. Do not permit water flooding or jetting methods of compaction.

b. Turfed or Seeded Areas and Miscellaneous Areas: Deposit backfill in layers of a maximum of 6 inch loose thickness, and compact in accordance with the Geotechnical Engineering Report as prepared by RHEA Engineering. Apply this requirement to all other areas not specifically designated above.

3.9.2 Backfill for Appurtenances

After the manhole, catch basin, inlet, or similar structure has been constructed and the concrete has been allowed to cure for 7 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.

3.10 Stone Placement

Place rock for rip-rap on prepared bedding to produce a well graded mass with the minimum practicable percentage of voids in conformance with lines and grades indicated. Distribute larger rock fragments, with dimensions extending the full depth of the rip-rap throughout the entire mass and eliminate "pockets" of small rock fragments. Rearrange individual pieces by mechanical equipment or by hand as necessary to obtain the distribution of fragment sizes specified above.

3.11 SUBGRADE PREPARATION

3.11.1 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. Proof roll the existing subgrade with six passes of a 15 ton, pneumatic-tired roller. Operate the roller in a systematic manner to ensure the number of passes over all areas, and at speeds between 2-1/2 to 3-1/2 mph. When proof rolling, provide one-half of the passes made with the roller in a direction perpendicular to the other passes. Notify the Contracting Officer a minimum of 3 days prior to proof rolling. Perform proof rolling in the presence of the Contracting Officer.

Undercut rutting or pumping of material as directed by the Contracting Officer and replace with fill and backfill material.

3.11.2 Construction

Shape subgrade to line, grade, and cross section, and compact as specified.

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3.11.3 Compaction

Finish compaction by sheepsfoot rollers, pneumatic-tired rollers, steel-wheeled rollers, vibratory compactors, or other approved equipment. Compact each layer of the embankment to at least 98 percent of laboratory maximum density as determined by ASTM D698. The Contractor shall submit a list of all equipment to be utilized for compacting, including the manufacturers' lift thickness limitations.

3.11.4 Subgrade for Pavements

Compact subgrade for pavements to at least 98 percent of the maximum dry density as determined by ASTM D 1557-91 and as specified in the Geotechnical Engineering Report as prepared by RHEA Engineering.

3.11.5 Subgrade for Shoulders

Compact subgrade for shoulders to at least 98 percent of the maximum dry density as determined by ASTM D 698 and as specified in the Geotechnical Engineering Report as prepared by RHEA Engineering.

3.11.6 Subgrade and Embankments

During construction, keep embankments and excavations shaped and drained.

Maintain ditches and drains along subgrade to drain effectively at all times. Do not disturb the finished subgrade by traffic or other operation.

Protect and maintain the finished subgrade in a satisfactory condition until ballast, subbase, base, or pavement is placed. Do not permit the storage or stockpiling of materials on the finished subgrade. Do not lay subbase, base course, ballast, or pavement until the subgrade has been checked and approved, and in no case place subbase, base, surfacing, pavement, or ballast on a muddy, spongy, or frozen subgrade.

The material for embankment shall be deposited in layers of not more than six inches (6") in thickness; the compaction in each layer shall equal or exceed 98% of the standard Proctor density as confirmed through soil compaction tests performed by an independent laboratory approved by the Contracting Officer and paid for by the Contractor. No breaks or irregularities in the distribution of the material or the formation of the layers will be allowed. The whole embankment shall be carried up evenly to the height given by the Contracting Officer in such a manner as to make compact and solid formation.

When pipe is to be laid in a fill, the embankment shall be brought to a height at least one (1) foot above the proposed top of the pipe before the trench is excavated. The embankment shall be excavated to the proper form and grade and the sewer placed thereon; after which the embankment shall be carried up to a height of not less than three (3) feet above the top of the sewer, the material being placed and rolled or rammmed in layers as above described.

In case the embankment over the sewer should obstruct any natural drainage, the Contractor will be required to do any work and furnish any material necessary to preserve natural drainage, to the satisfaction of the Contracting Officer.

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3.12 SHOULDER CONSTRUCTION

Construct shoulders of satisfactory excavated material or as otherwise shown or specified. Construct shoulders immediately after adjacent paving is complete. In the case of rigid pavements, do not construct shoulders until permission of the Contracting Officer has been obtained. Compact the entire shoulder area to at least the percentage of maximum density as specified in paragraph SUBGRADE PREPARATION above, for specific ranges of depth below the surface of the shoulder. Finish compaction by sheepsfoot rollers, pneumatic-tired rollers, steel-wheeled rollers, vibratory compactors, or other approved equipment. Finish shoulder construction in proper sequence in such a manner that adjacent ditches will be drained effectively and that no damage of any kind is done to the adjacent completed pavement. Align the completed shoulders true to grade and shaped to drain in conformity with the cross section shown.

3.13 FINISHING

Finish the surface of excavations, embankments, and subgrades to a smooth and compact surface in accordance with the lines, grades, and cross sections or elevations shown. Provide the degree of finish for graded areas within

0.1 foot of the grades and elevations indicated except that the degree of finish for subgrades specified in paragraph SUBGRADE PREPARATION. Finish gutters and ditches in a manner that will result in effective drainage.

Finish the surface of areas to be turfed from settlement or washing to a smoothness suitable for the application of turfing materials. Repair graded, topsoiled, or backfilled areas prior to acceptance of the work, and re-established grades to the required elevations and slopes.

3.14 Temporary Paving

In all paved areas other than State roadways and in all unpaved areas used as thoroughfares, road shoulders, driveways or parking areas, the Contractor shall provide over all backfilled excavations a temporary paving consisting of a layer of crushed stone conforming in grading requirements of three (3) inch coarse aggregate, which shall be eight (8) inches in depth after approved compaction.

The stone shall be spread on a thoroughly tamped subgrade and shall be rolled with a ten-ton roller until there is no evidence of further compaction or settlement.