Attachment_2_-_Revised_Specifications_8_21.pdf

Summary of changes to Construction Specifications.

Revised specifications are attached.

Construction Specification 8, Mobilization and Demobilization, Section 4. Item b: This item shall also include constructing, maintaining, and removing any access roads which are needed to construct and inspect the project. The site is to be access by a Right-of-Way located at the end of State Drive. The contractor is responsible for staying within the construction limits and regrading all access areas to original condition upon departure. The contractor is also responsible for repairing any areas outside of the construction limits back to original conditions which may have been damaged by the contractor during access.

Construction Specification 8, Mobilization and Demobilization, Section 4. Item c: Necessary clearing of access areas shall be the minimum deemed necessary in order to safely move machinery to the work locations. This may include the felling of trees and removal of stumps within the construction limits.

Any removed materials shall be piled along either side of the lane. Clearing of the access route shall be limited to a width of 20ft.

Construction Specification 21, Excavation, Section 10. Item g: In exception to Section 7, Borrow excavation: Borrow pits shall blend with existing topography and are allowed to pond water, drainage does not need to be provided.

Construction Specification 21, Excavation, Section 10. Item h: All existing drain tile or pipes that are removed to construct the embankments shall be disposed of off-site by the contractor.

(210-VI-NEH, May 2001)

Construction Specification 8—Mobilization and Demobilization

1. Scope The work consists of the mobilization and demobilization of the contractor's forces and equipment necessary for performing the work required under the contract. It does not include mobilization and demobilization for specific items of work for which payment is provided elsewhere in the contract. Mobilization will not be considered as work in fulfilling the contract requirements for commencement of work.

2. Equipment and material Mobilization shall include all activities and associated costs for transportation of contractor's personnel, equipment, and operating supplies to the site; establishment of offices, buildings, and other necessary general facilities for the contractor's operations at the site; premiums paid for performance and payment bonds including coinsurance and reinsurance agreements as applicable; and other items specified in section 4 of this specification.

Demobilization shall include all activities and costs for transportation of personnel, equipment, and supplies not required or included in the contract from the site; including the disassembly, removal, and site cleanup of offices, buildings, and other facilities assembled on the site specifically for this contract.

This work includes mobilization and demobilization required by the contract at the time of award. If additional mobilization and demobilization activities and costs are required during the performance of the contract as a result of changed, deleted, or added items of work for which the contractor is entitled to an adjustment in contract price, compensation for such costs will be included in the price adjustment for the item or items of work changed or added.

3. Payment Payment will be made as the work proceeds, after presentation of paid invoices or documentation of direct costs by the contractor showing specific mobilization and demobilization costs and supporting evidence of the charges of suppliers, subcontractors, and others. When the total of such payments is less than the lump sum contract price, the balance remaining will be included in the final contract payment. Payment of the lump sum contract price for mobilization and demobilization will constitute full compensation for completion of the work.

Payment will not be made under this item for the purchase costs of materials having a residual value, the purchase costs of materials to be incorporated in the project, or the purchase costs of operating supplies.

4. Items of work and construction details

4. Items of work to be performed in conformance with this specification and the construction details therefore are:

a) This item shall include obtaining all work to move equipment and supplies onto and from the site. It is the contractor’s responsibility to comply with all local, state, and federal requirements related to the completion of this work.

b) This item shall also include constructing, maintaining, and removing any access roads which are needed to construct and inspect the project. The site is to be access by a Right-of-Way located at the end of State Drive. The contractor is responsible for staying within the construction limits and regrading all access areas to original condition upon departure. The contractor is also responsible for repairing any areas outside of the construction limits back to original conditions which may have been damaged by the contractor during access.

c) Necessary clearing of access areas shall be the minimum deemed necessary in order to safely move machinery to the work locations. This may include the felling of trees and removal of stumps within the construction limits. Any removed materials shall be piled along either side of the lane. Clearing of the access route shall be limited to a width of 20ft.

d) The Contractor shall comply with PA One-Call requirements at least three days prior to any construction activities.

e) Payment for this work item will be lump sum upon successful completion and removal of all equipment and materials from the site. A signed Certificate of Conformance from the contractor, referencing this project and the work items indicated in the Bid Schedule must be provided to the inspector prior to final payment.

Construction Specification 21—Excavation

1. Scope The work shall consist of the excavation required by the drawings and specifications and disposal of the excavated materials.

2. Classification Excavation is classified as common excavation, rock excavation, or unclassified excavation in accordance with the following definitions.

Common excavation is defined as the excavation of all materials that can be excavated, transported, and unloaded using heavy ripping equipment and wheel tractor-scrapers with pusher tractors or that can be excavated and dumped into place or loaded onto hauling equipment by excavators having a rated capacity of one cubic yard or larger and equipped with attachments (shovel, bucket, backhoe, dragline, or clam shell) appropriate to the material type, character, and nature of the materials.

Rock excavation is defined as the excavation of all hard, compacted, or cemented materials that require blasting or the use of ripping and excavating equipment larger than defined for common excavation. The excavation and removal of isolated boulders or rock fragments larger than 1 cubic yard encountered in materials otherwise conforming to the definition of common excavation shall be classified as rock excavation. The presence of isolated boulders or rock fragments larger than 1 cubic yard is not in itself sufficient cause to change the classification of the surrounding material.

For the purpose of these classifications, the following definitions shall apply:

Heavy ripping equipment is a rear-mounted, heavy duty, single-tooth, ripping attachment mounted on a track type tractor having a power rating of at least 250 flywheel horsepower unless otherwise specified in section 10.

Wheel tractor-scraper is a self-loading (not elevating) and unloading scraper having a struck bowl capacity of at least 12 cubic yards.

Pusher tractor is a track type tractor having a power rating of at least 250 flywheel horsepower equipped with appropriate attachments.

Unclassified excavation is defined as the excavation of all materials encountered, including rock materials, regardless of their nature or the manner in which they are removed.

3. Blasting The transportation, handling, storage, and use of dynamite and other explosives shall be directed and supervised by a person(s) of proven experience and ability who is authorized and qualified to conduct blasting operations.

Blasting shall be done in a manner as to prevent damage to the work or unnecessary fracturing of the underlying rock materials and shall conform to any special requirements in section 10 of this specification. When specified in section 10, the contractor shall furnish the engineer, in writing, a blasting plan before blasting operations begin.

4. Use of excavated material Method 1—To the extent they are needed, all suitable material from the specified excavations shall be used in the construction of required permanent earthfill or rockfill. The suitability of material for specific purposes is determined by the engineer. The contractor shall not waste or otherwise dispose of suitable excavated material.

Method 2—Suitable material from the specified excavations may be used in the construction of required earthfill or rockfill. The suitability of material for specific purposes is determined by the engineer.

5. Disposal of waste materials Method 1—All surplus or unsuitable excavated materials are designated as waste and shall be disposed of at the locations shown on the drawings.

Method 2—All surplus or unsuitable excavated materials are designated as waste and shall be disposed of by the contractor at sites of his own choosing away from the site of the work. The disposal shall be in an environmentally acceptable manner that does not violate local rules and regulations.

6. Excavation limits Excavations shall comply with OSHA Construction Industry Standards (29CFR Part 1926) Subpart P, Excavations, Trenching, and Shoring. All excavations shall be completed and maintained in a safe and stable condition throughout the total construction phase. Structure and trench excavations shall be completed to the specified elevations and to the length and width required to safely install, adjust, and remove any forms, bracing, or supports necessary for the installation of the work. Excavations outside the lines and limits shown on the drawings or specified herein required to meet safety requirements shall be the responsibility of the contractor in constructing and maintaining a safe and stable excavation.

7. Borrow excavation When the quantities of suitable material obtained from specified excavations are insufficient to construct the specified earthfills and earth backfills, additional material shall be obtained from the designated borrow areas. The extent and depth of borrow pits within the limits of the designated borrow areas shall be as specified in section 10 or as approved by the engineer.

Borrow pits shall be excavated and finally dressed to blend with the existing topography and sloped to prevent ponding and to provide drainage.

8. Overexcavation Excavation in rock beyond the specified lines and grades shall be corrected by filling the resulting voids with portland cement concrete made of materials and mix proportions approved by the engineer. Concrete that will be exposed to the atmosphere when construction is completed shall meet the requirements of concrete selected for use under Construction Specification 31, Concrete for Major Structures, or 32, Structure Concrete, as appropriate.

Concrete that will be permanently covered shall contain not less than five bags of cement per cubic yard. The concrete shall be placed and cured as specified by the engineer.

Excavation in earth beyond the specified lines and grades shall be corrected by filling the resulting voids with approved, compacted earthfill. The exception to this is that if the earth is to become the subgrade for riprap, rockfill, sand or gravel bedding, or drainfill, the voids may be filled with material conforming to the specifications for the riprap, rockfill, bedding, or drainfill.

Before correcting an overexcavation condition, the contractor shall review the planned corrective action with the engineer and obtain approval of the corrective measures.

9. Measurement and payment For items of work for which specific unit prices are established in the contract, the volume of each type and class of excavation within the specified pay limits is measured and computed to the nearest cubic yard by the method of average cross-sectional end areas or by methods outlined in section 10 of this specification. Regardless of quantities excavated, the measurement for payment is made to the specified pay limits except that excavation outside the specified lines and grades directed by the engineer to remove unsuitable material is included. Excavation required because unsuitable conditions result from the contractor's improper construction operations, as determined by the engineer, is not included for measurement and payment.

Method 1—The pay limits shall be as designated on the drawings.

Method 2—The pay limits shall be defined as follows:

a. The upper limit shall be the original ground surface as it existed before the start of construction operations except that where excavation is performed within areas designated for previous excavation or earthfill, the upper limit shall be the modified ground surface resulting from the specified previous excavation or earthfill.

b. The lower and lateral limits shall be the neat lines and grades shown on the drawings.

Method 3—The pay limits shall be defined as follows:

a. The upper limit shall be the original ground surface as it existed before the start of construction operations except that where excavation is performed within areas designated for previous excavation or earthfill, the upper limit shall be the modified ground surface resulting from the specified previous excavation or earthfill.

b. The lower and lateral limits shall be the true surface of the completed excavation as directed by the engineer.

Method 4—The pay limits shall be defined as follows:

a. The upper limit shall be the original ground surface as it existed before the start of construction operations except that where excavation is performed within areas designated for previous excavation or earthfill, the upper limit shall be the modified ground surface resulting from the specified previous excavation or earthfill.

b. The lower limit shall be at the bottom surface of the proposed structure.

c. The lateral limits shall be 18 inches outside of the outside surface of the proposed structure or shall be vertical planes 18 inches outside of and parallel to the footings, whichever gives the larger pay quantity, except as provided in d below.

d. For trapezoidal channel linings or similar structures that are to be supported upon the sides of the excavation without intervening forms, the lateral limits shall be at the underside of the proposed lining or structure.

e. For the purposes of the definitions in b, c, and d, above, any specified bedding or drainfill directly beneath or beside the structure will be considered to be a part of the structure.

All methods—The following provisions apply to all methods of measurement and payment.

Payment for each type and class of excavation is made at the contract unit price for that type and class of excavation. Such payment will constitute full compensation for all labor, materials, equipment, and all other items necessary and incidental to the performance of the work except that extra payment for backfilling overexcavation will be made in accordance with the following provisions.

Payment for backfilling overexcavation, as specified in section 8 of this specification, is made only if the excavation outside specified lines and grades is directed by the engineer to remove unsuitable material and if the unsuitable condition is not a result of the contractor's improper construction operations as determined by the engineer.

Compensation for any item of work described in the contract, but not listed in the bid schedule is included in the payment for the item of work to which it is made subsidiary. Such items and the items to which they are made subsidiary are identified in section 10 of this specification.

10. Items of work and construction details

10. Items of work to be performed in conformance with this specification and the construction details therefore are:

a) This item shall consist of all excavation work necessary to create two (2) new wetland areas and rehabilitate three (3) existing wetland areas as indicated on the drawings. The wetland areas include one (1) Category I embankment, three (3) Category II embankments, and one (1) pond. The work shall include all excavation necessary to create the new and rehabilitate the existing wetland areas.

b) All excavation shall take place within the designated areas depicted on the construction drawings. These areas shall be as staked in the field.

c) Organic soils and soils with little or no bearing strength, located in fill areas, shall be removed and replaced with compacted fill. Any gravelly-sandy soils encountered in the embankment shall be over excavated by 1.0’ and replaced with good non-permeable soil.

The NRCS representative prior to onset of earthfill placement shall approve the subgrade for earthfill. Method for disposal of waste materials shall be Method 1.

d) Specified borrow areas are shown on the plans, in addition to the designated areas borrow may be obtained within the proposed impoundment and directly adjacent to the embankment. The borrow area should have finished slopes no steeper than 3:1 and topsoil shall be replaced when completed. Borrow may be no deeper than 3’ below original grade and only as necessary to construct the proposed embankment. Method for use of excavated material shall be Method 2.

e) Payment for this work item will be lump sum upon completion of all wetland areas.

f) Items of work subsidiary to this bid item are:

a. Clearing and Grubbing – Construction Specification 2

b. Removal of Water – Construction Specification 11

g) In exception to Section 7, Borrow excavation: Borrow pits shall blend with existing topography and are allowed to pond water, drainage does not need to be provided.

h) All existing drain tile or pipes that are removed to construct the embankments shall be disposed of off-site by the contractor.