Amend 001 Revised CS 11 Removal of Water_final.pdf

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Construction Specification 11—Removal of Water

1. Scope The work consists of the removal of surface water and ground water as necessary to perform the construction required by the contract in accordance with the specifications. It shall include: (1) constructing, installing, building, and maintaining all necessary temporary water containment facilities, channels, and diversions; (2) furnishing, installing, and operating all necessary pumps, piping, and other facilities and equipment; and (3) removing all such temporary works and equipment after their intended function is no longer required.

2. Diverting surface water The contractor shall install, maintain, and operate all cofferdams, channels, flumes, sumps, and all other temporary diversion and protective works needed to divert streamflow and other surface water through or around the construction site. Control of surface water shall be continuous during the period that damage to construction work could occur. Unless otherwise specified and/or approved, the diversion outlet shall be into the same drainageway that the water would have reached before being diverted.

The contractor shall furnish the contracting officer, in writing, a proposed plan for diverting surface water before beginning any construction activities for which a diversion is required, unless waived in section 8 of this specification. Acceptance of this plan or the waiving of the plan requirement will not relieve the contractor of the responsibilities related to this activity during the process of completing the work as specified.

3. Dewatering the construction site Foundations, cutoff trenches, and all other parts of the construction site shall be dewatered and kept free of standing water and muddy conditions as necessary for the proper execution of the work. The contractor shall furnish, install, operate, and maintain all drains, sumps, pumps, casings, well points, and all other equipment required to properly dewater the site as specified.

Dewatering systems that cause a loss of soil fines from the foundation areas will not be permitted.

The contractor shall furnish the contracting officer, in writing, a proposed plan for dewatering before commencing with any construction activity for which dewatering may be required, unless waived in section 8 of this specification. Acceptance of this plan or the waiving of the plan requirement will not relieve the contractor of the responsibilities for completing the specified work.

4. Dewatering borrow areas The contractor shall maintain all borrow areas free of surface water or otherwise provide for timely and effective removal of surface and subsurface water that accumulates within the borrow area, unless waived in section 8 of this specification. Borrow material shall be processed as necessary to achieve proper and uniform moisture content at the time of placement.

If pumping to dewater borrow areas is included as a bid item of work in the bid schedule, each pump discharge pipe shall be equipped with a water meter. The meter shall be such that the measured quantity of water is accurate within 3 percent of the true quantity. The contractor shall

11-2 provide necessary support to perform accuracy tests of the water meter when requested by the contracting officer.

5. Erosion and pollution control Removal of water from the construction site, including the borrow areas, shall be accomplished so that erosion and the transporting of sediment and other pollutants are minimized. Dewatering activities shall be accomplished in a manner that the water table water quality is not altered.

Pollution control activities shall not conflict with the requirements of Construction Specification 5, Pollution Control, if it is a part of this contract.

6. Removal of temporary works When temporary works are no longer needed, the contractor shall remove and return the area to a condition similar to that which existed before construction. Areas where temporary works were located shall be graded for sightly appearance with no obstruction to natural surface waterflows or the proper functioning and access to the works of improvement installed. The contractor shall exercise extreme care during the removal stages to minimize the loss of soil sediment and debris that was trapped during construction.

Pipes, casings, and any other material used to dewater the site shall be removed from temporary wells. The wells shall be filled to ground level with clean gravel or other suitable material approved by the contracting officer. The contractor shall exercise extreme care to prevent pollution of the ground water by these actions.

7. Measurement and payment Method 1—Items of work listed in the bid schedule for removal of water, diverting surface water, and dewatering construction sites and borrow areas are paid for at the contract lump sum prices.

Such payment will constitute full compensation for all labor, equipment, tools, and all other items necessary and incidental to the completion of the work.

Method 2—Items of work listed in the bid schedule for removal of water, diverting surface water, dewatering construction sites, and dewatering borrow areas are paid for at the contract lump sum prices. Such payment will constitute full compensation for furnishing, installing, operating, and maintaining the necessary trenches, drains, sumps, pumps, and piping and for all labor, equipment, tools, and all other items necessary and incidental to the completion of the work. The exception is that additional payment for pumping to dewater borrow areas and the removal of water will be made as described in the following paragraph.

If pumping to dewater borrow areas is a contract bid item, payment is made at the contract unit price, which shall be the price per 1,000 gallons shown in the bid schedule. Such payment will constitute full compensation for pumping only. Compensation for equipment and preparation and for other costs associated with pumping is included in the lump sum payment for removal of water or the lump sum payment for dewatering the borrow areas. Payment is made only for pumping that is necessary to dewater borrow areas that cannot be effectively drained by gravity or that must have the water table lowered to be usable as a suitable borrow source. Pumping for other purposes will not be included for payment under this item.

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

Compensation for any item of work described in the contract, but not listed in the bid schedule is included in the payment for the contract line item to which it is made subsidiary. Such items and

11-3 the items to which they are made subsidiary are identified in section 8 of this specification.

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8. Items of work and construction details

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

a. Removal of Water, General

(1) The existing site data and other information provided in this specification and the Drawings are for informational purposes to assist the Contractor in the design of temporary diversion structures. Due diligence was exercised to prepare this information, but the accuracy is not guaranteed and use of this information is at the discretion of the Contractor.

(2) Hibernia Dam is located in an ungaged watershed; therefore, peak inflows for flood events cannot be determined from historical information and must be estimated.

The drainage area of the watershed is approximately 4.61 square miles.

(3) The United States Geological Society, in cooperation with the Pennsylvania

Department of Environmental Protection, the Federal Emergency Management Agency, the Pennsylvania State Association of Township Supervisors, and the Susquehanna River Basin Commission, developed the StreamStats program.

StreamStats is a web-based application (https://water.usgs.gov/osw/streamstats/pennsylvania.html) that incorporates regression equations for estimating numerous streamflow statistics. Using StreamStats, peak discharges for a range of return periods were evaluated. The results are summarized in the table shown below.

The Contractor is responsible for designing the diversion of water system including establishing the top elevation of all cofferdams. The Contractor is also responsible for computing and providing independent analyses including computed inflows and stage-discharge ratings for the Contractor’s diversion system in the Contractor’s Surface Water Diversion Plan.

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(4) In addition to streamflow, surface water flow of unknown flow rate may be encountered during excavation near the toe of the dam for construction of the filtered rock toe. It shall be the Contractor’s sole responsibility to collect, filter and convey this flow away from the active work area.

(5) The Contractor may not operate existing reservoir controls including the outlet works or conservation release valve.

b. Bid Item 10, Dewatering the Construction Site

(1) This Bid Item shall consist of all costs associated with planning, designing, furnishing, installing, operating, maintaining, monitoring and removing all foundation dewatering systems necessary for the removal of surface water and ground water to permit construction of the following:

(a) New reinforced concrete cutoff wall.

(b) New filtered rock toe.

(2) The Contractor shall engage the services of a Dewatering Specialist to design the dewatering system, oversee its installation, periodically evaluate its performance, and identify and implement modifications and/or additions to the system to meet the performance required under this contract. The Contractor’s Dewatering Specialist shall be a registered Professional Engineer and shall have at least 5 years of experience in design of dewatering systems, shall have personally designed dewatering systems having requirements similar to this contract, shall oversee installation and operation of the dewatering system verifying proper performance and required lowering of groundwater levels, and shall be available for meetings at the project site when requested within 24 hours notice.

(3) The Contractor shall submit a Dewatering Plan to the COR for review within 21 calendar days after the date of the Notice to Proceed.

(a) The Dewatering Plan shall include supporting drawings and calculations indicating but not limited to the stratigraphy, proposed depths of excavation, expected drawdown levels (elevations in feet), layout (station and offset or coordinate) and details of dewatering system components, how the dewatering system will be integrated during construction with the Diverting of Surface Water being performed under Bid Item 13 and with the Contractor’s Erosion and Sediment Control Plan, installation and removal procedures and backup equipment and emergency power sources.

(b) The Dewatering Plan shall bear the Professional Engineer’s seal of the approved Dewatering Specialist. Contractor shall be solely responsible for the adequacy of the plan and coordination with other work. The dewatering specialist shall be available for consultation prior to acceptance of dewatering plan. Review of the Contractor’s Dewatering Plan, with or without comments by the COR, does not relieve the Contractor of any responsibility for the adequacy of the Contractor’s dewatering system. The Contractor shall be

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solely responsible for the adequacy of the dewatering system and for coordination with other work.

(c) Prior to developing the detailed dewatering plan, the Contractor and the Dewatering Specialist shall meet with the COR to review the site conditions and the contract requirements for dewatering.

(d) The dewatering plan shall contain provisions for incrementally adding, modifying, expanding, and/or supplementing the dewatering system as the work progresses.

(e) The dewatering plan shall include a log for piezometer monitoring as described in Section 8.b(5).

(4) It is the intent and contract requirement that the Contractor shall design, furnish and install dewatering facilities and perform specified dewatering prior to initiating any excavation. Dewatering systems shall remove all seepage and standing water from the foundation grades at every location where excavation is required and where earthfill material; drainfill material; reinforced, dental or backfill concrete or any other materials are to be placed. No standing water on the excavation surface is permitted at any location. The dewatering process shall not remove, erode or pipe any material from the embankment or foundation. Monitor discharge for sediment during construction, and cease dewatering operations and associated construction operations until system is modified and successfully dewatering with no material removal.

At locations where fill materials are to be placed, excavation surfaces shall be free from all flows of water or standing water. Any excavation surface that is unstable in the opinion of the COR due to the presence of water shall be fully stabilized with additional dewatering facilities before commencing with any activities thereon.

The Dewatering Specialist shall be available for consultation during installation of dewatering components and during construction, regardless of system performance.

At any time water is encountered on the surface of any excavation or work surface or the required drawdown below construction operations is not maintained, the Contractor shall cease excavation or other construction operations, have the site inspected by the Dewatering Specialist, and implement appropriate supplemental dewatering operations. Operations shall be resumed only when surfaces are free of all flowing or standing water.

(5) The following factors shall be considered when planning the dewatering system for the required excavations:

(a) The depth and planned extent of the foundation excavations and the capability to accommodate excavation if needed to remove unsuitable material that may be encountered at or beyond the foundation grades and excavation limits shown on the Drawings.

(b) Long-term dewatering of the excavations is required and a written dewatering plan identified in Section 8.b.3 will be required to be submitted

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and accepted. The plan shall explain and detail the proposed dewatering methods, anticipated results of dewatering activities, plan of action to achieve required results, identification and application of dewatering system monitoring, provisions for backup equipment and erosion, sedimentation control details for all discharges.

(c) The reservoir will not be drawn down throughout the dewatering period except for naturally occurring seasonal fluctuations.

(d) An uncontrolled, unfiltered seep was identified and active from October 2009 through March 2010 at approximately Station 3+70, approximately one foot upslope from the top of the existing rock gutter. This occurrence of seepage coincided with elevated heads (i.e., greater than El. 549) within piezometer P2.

(e) Artesian conditions were not observed during the drilling of GF-106 at the downstream toe of the embankment, however, the foundation soils beneath the embankment are known to be water bearing. The Contractor’s dewatering plan shall indicate how artesian conditions or free water in the excavation will be filtered and controlled, if encountered.

(f) Existing piezometers may be used to monitor groundwater levels during dewatering and excavation. In addition, monitoring features shall include any additional monitoring devices, as included in the approved Dewatering Plan, that the Contractor considers necessary to monitor the performance of the dewatering system

(6) Do not mobilize dewatering equipment or materials to the site until the Dewatering

Specialist’s dewatering plan has been approved by the COR.

(7) Dewatering systems shall be constructed outside the limits of excavations so they do not interfere with fill material or concrete placement. The general use of sumps within the limits of the “footprint” of the fill material as a primary means of accomplishing dewatering shall be avoided as much as possible. Sumps shall not be utilized within the limits of the fill material without permission from the COR.

Dewatering systems located within areas where fill materials will be placed shall be designed to accommodate the fill placement while maintaining dewatering or shall be staged design to allow removal of a first stage system prior to fill placement with a second stage system to dewater fill placement areas.

(8) Begin dewatering operations and supplement the system to achieve the required dewatering depths prior to excavation. The Contractor shall monitor the dewatering by recording water level readings in all existing piezometers and any additional monitoring devices per the approved Dewatering Plan on daily intervals.

All piezometer data shall be provided to the COR on the first working day of each week.

(9) Dewatering operations shall be continuous for the duration of all work or activities affected by dewatering unless specific permission to temporarily discontinue

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dewatering is provided in writing by the COR. Backup equipment and emergency power sources shall be provided at all times to meet this requirement.

(10) The Contractor is responsible for protecting all elements of the dewatering facilities throughout the duration of the Contract and is responsible for replacing any elements of the dewatering facilities that become inoperable or damaged regardless of the reason.

(11) Foundation materials located at or below the limits of excavation shown on the

Drawings or indicated in the Specifications, and which are disturbed by equipment operating on inadequately dewatered surfaces, by uplift forces caused by inadequate dewatering, or by any other mechanism associated with inadequate dewatering shall be dewatered, overexcavated, and reconstructed to specified grades with backfill concrete, or as directed by the COR, by the Contractor at no additional cost.

(12) All dewatering system components, once installed and accepted, shall be operational at all times and no components shall be removed or turned off without the written permission of the COR. Unless otherwise specifically permitted, dewatering systems shall be operated continuously until all permanent construction is complete to a level 5 feet higher than the water level that could exist with the system turned off. When the COR grants permission to remove wells or relief wells located outside the excavation areas the wells, or relief wells shall be fully cleaned out and tremie grouted full depth with neat cement grout mixed in a volumetric mix ratio of 0.6 water to 1 cement. Backfill any excavated sumps located outside the foundation areas with material indicated in the approved Dewatering Plan as directed by the COR.

(13) Flowing water shall not be allowed to come in contact with any newly placed concrete for a period of 48 hours after the concrete is placed.

(14) The Contractor is responsible for providing the proper facilities necessary to dispose of all water discharged during the conduct of the work in a manner acceptable to all regulatory agencies. The Contractor shall provide silt fence, straw bales and, if necessary, construct sediment basins to collect sediment from the discharge water before it is allowed to flow into any surface watercourse.

(15) Measurement and payment will be by Method 1 of Section 7.

Payment will be made as the work proceeds, after receipt of invoices from the Contractor showing the cost of work performed for the payment period. If the total of incremental payments is less than the Contract Lump Sum Price for removal of water, the balance will be included in the final contract payment. Total payment will be the Contract Lump Sum Price for removal of water, regardless of actual cost to the Contractor.

(16) Items subsidiary to this Bid Item include:

(a) Excavation, Dewatering the Construction Site, Unclassified, Construction

Specification 21 – Earthfill.

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(b) Earthfill, Dewatering the Construction Site, Construction Specification 23

– Earthfill.

(c) Temporary Piezometers, Construction Specification 405 – Instrumentation.

c. Bid Item 11, Diverting Surface Water

(1) This Bid Item shall consist of furnishing, installing, operating, maintaining and repairing all works necessary for diverting stream flows and other surface flows of water from the construction site, waste areas, and staging areas, and construction and removal of all cofferdams and diversion works as may be required for performing the Work.

(2) Diversion Requirements:

(a) The Contractor is responsible for protecting the construction areas from flooding for the duration of the construction period. Diverting surface water shall consist of furnishing and installing all works necessary for construction of surface water diversion works and responding to flooding conditions. This includes constructing and maintaining the cofferdams, conduits and temporary diversions installed for streamflow diversion as required for construction of all project features including the, downstream embankment berm regrading, concrete cutoff wall, downstream rock filtered toe, and permanent wetland crossing. This also includes removal and/or disposal of all temporary diversion works.

(b) Flow through the existing principal spillway and the existing auxiliary spillway may not be obstructed at any time due to the Contractor’s operations. All temporary diversion works, including temporary cofferdams, must be constructed in such a way that avoids impacts to the discharge capacity of the principal spillway and auxiliary spillway.

Cofferdams may only be constructed near the toe of the dam for preventing downstream backwater from flooding of the work area.

(3) Minimum Level of Flood Protection: At a minimum, the diversion of water system shall be capable of passing the flow as specified in Paragraph 8.a.(3) and Paragraph 8.a.(4). The Contractor must determine the minimum level of flood protection that he is willing to accept and this level of protection must be identified in the surface water diversion plan. Selection of the level of protection for surface water diversion is risk-based. The Contractor must weigh the economics of building a larger cofferdam and/or installing a larger diversion conduit versus the cost of a potentially flooded working area at all stages of construction. The Contractor shall determine the size and location of any proposed cofferdams such that the Contractor’s selected level of protection is provided and access to the construction site is maintained.

(4) Surface Water Diversion Plan: The Contractor is responsible for designing and sizing the temporary diversion channels, diversion conduits, cofferdams, stream crossings, and all other components, elements and features of the surface water

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diversion works. Proposed construction sequencing shall be documented with the Surface Water Diversion Plan. The Contractor is required to submit a Surface Water Diversion Plan, even if the suggested surface water diversion scheme shown on the Drawings is utilized. The Contractor shall submit the proposed Surface Water Diversion Plan to the COR for review and comment within 21 calendar days after the date of the Notice to Proceed and shall include the following items:

(a) General and detailed drawings and specifications bearing the seal of a registered Professional Engineer for all cofferdams, diversion conduits, diversion channels, stream crossings, or any other features of the surface water diversion works throughout all stages of construction.

(b) Hydrologic and hydraulic computations detailing the capacity of the surface water diversion system and the level of flood protection provided by the system.

(c) The design of any proposed cofferdams including location, elevations, top width, side slopes, material selection and placement, liners, access road locations, and any other pertinent features.

(d) Design calculations and detailed drawings of all temporary diversion conduits used in the Contractor’s surface water diversion plan including material properties, design loads, design assumptions, and specific installation procedures and testing requirements.

(e) Schedule showing the proposed time, sequence and duration of operation of the surface diversion works.

(f) Locations and limits of required excavation and fill areas, including any borrow sources.

(g) Sedimentation control features.

(h) Method of removal without damaging permanent work.

(i) Clearances provided between the permanent work and the surface water diversion plan features and all other data necessary to portray a clear understanding of proposed surface water diversion plan.

(j) The Contractor’s Surface Water Diversion Plan and any subsequent revisions that may be submitted by the Contractor for acceptance shall be prepared and sealed by a registered Professional Engineer with a minimum of 5 years experience preparing technical designs and the functional application of temporary diversion of water systems. Acceptance of the surface water diversion plan by the COR will not relieve the Contractor from full responsibility for the adequacy of the diversion and protective works, or for furnishing all equipment, labor and materials, and performing all operations in connection with the diversion of flows during construction; nor shall such acceptance be construed as obligating the Contracting Officer or COR for any loss or damage resulting from the diversion operations.

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(7) Revisions to the Surface Water Diversion Plan: Revisions to the accepted Surface

Water Diversion Plan shall be made at no additional cost as conditions warrant and as required by the Contracting Officer or COR to protect all existing facilities, and/or partially completed work. Contractor is solely responsible for confirming site conditions and shall revise the surface water diversion plan at no additional cost if any discrepancies between actual site conditions and information shown on the Drawings exist. All revisions must be approved by the COR.

(8) Rock and Earth Fill Cofferdams: If rock or earth fill materials are used in the construction of a cofferdam, the cofferdam shall be constructed and removed in accordance with Construction Specification 27 – Diversions and Waterways, Construction Specification 21 – Excavation, and Construction Specification 23 - Earthfill. Earth or rockfill material used in the construction of the cofferdam shall be obtained from within the excavation limits identified on the Drawings or from an off-site location. The Contractor may request a temporary borrow area within the construction limits with approval from the COR, but earth or rockfill borrow material for use in cofferdams shall not be excavated from the embankment or within 20 feet of the embankment. If a borrow area is approved, the Contractor is required to return the fill material to the borrow area such that the area is restored to original elevation and grade, and provide stabilization and protective cover as required by the Drawings. All other materials including pipes, synthetic liners, etc.

shall be salvaged by the Contractor or disposed of off-site by the Contractor in a lawfully approved landfill area. All environmental permitting associated with land disturbance at any borrow areas shall be the Contractor’s sole responsibility, and all necessary permits will be obtained by the Contractor at no additional cost.

(9) Seepage and Leakage: Seepage and leakage may occur through, under, and around the cofferdams or other elements of the surface water diversion works. Systems for diverting surface water shall be designed and modified as necessary to handle such seepage and leakage.

(10) Provisions: The Contractor shall provide the level of flood protection identified in the Contractor’s Surface Water Diversion Plan and the Contractor agrees to the following provisions:

(a) Pursue the diversion operations in a manner that will prevent blockage or clogging of the diversion works.

(b) Provide the Contracting Officer with a telephone number for the person who will be available at all times during the construction period.

(c) If, at any time during the Contractor's operations, weather conditions occur or are anticipated to occur that might be expected to cause flooding that would endanger the integrity of the work under this Contract, the Contractor shall take all possible precautions to protect partial or completed permanent work from damage, and perform all other work associated with the Contractor's operations as may be required by the COR in the event of an anticipated

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flood.

(d) Evaluate current stream flow conditions, current weather conditions, and forecasted weather conditions and accept sole responsibility for determining if such conditions are anticipated to cause flooding.

(e) Accept responsibility for any and all such precautionary measures that may be required in the event of an anticipated flood and any and all work necessary to reestablish construction site and activities subsequent thereto, at no additional cost.

(11) Damages to Contract Work and Existing Structures, Features, and Facilities:

(a) The Contractor shall have no claim for additional compensation resulting from flooding or flood damage during construction. Should such conditions occur the Contractor shall repair or replace any damaged work or existing features. This shall include but is not limited to the restoration of cofferdams; restoration of embankments including dam embankments and side slopes; dewatering of the construction site; and cleaning of concrete surfaces, reinforcing steel, and other items and surfaces. The Contractor shall be wholly responsible for any and all damages to partially completed or completed contract work, including pumping of floodwaters from work areas and all subsequent cleanup, and for any and all flood damages to public and private property, upstream or downstream from the site, resulting from the construction activities. Any and all flood induced damages to partial or completed work and to public and private property resulting from the Contractor's activities shall be repaired or replaced as approved by the COR at the Contractor’s expense.

(b) Flowing water shall not be allowed to come in contact with any newly placed concrete for a period of 48 hours after the concrete is placed. The COR may request removal and replacement of the concrete at the Contractor’s expense if such conditions occur.

(c) The existing condition of the existing 36-inch reinforced concrete principal spillway conduit and existing impact basin shall be maintained throughout the duration of construction. Any leaks or damage to the existing impact basin, the existing 36-inch principal spillway conduit or their appurtenances caused by debris or the Contractor’s activities shall be repaired by the Contractor, at the Contractor’s expense, as approved by the COR.

(d) No additional compensation will be provided to repair damaged existing features or facilities or to repair contract work. Contractor must complete all repair work to the satisfaction of the COR with no additional compensation.

(12) Reservoir Pool Elevation: The surface water diversion works must maintain the pre-construction state of the reservoir until all construction is complete as determined by the COR. The surface water diversion works shall also protect all

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work areas downstream of the embankment for the duration of construction, including but not limited to the filtered rock toe placement.

(13) Methods of Diversion around the Dam: The surface water diversion works shall utilize the existing 36-inch reinforced concrete principal spillway conduit for diverting water as the primary method for diverting water from the reservoir to the receiving stream downstream of the dam. Siphons, pumps and other secondary methods are not permitted for diverting water around the dam, over top of the dam or over top of the auxiliary spillway.

(14) Minimum Releases: The Sponsor is required to maintain a minimum release to the stream immediately downstream of the dam at all times of the lesser of 1.0 cfs or natural inflow to the reservoir. The Contractor’s temporary diversion of water works shall be designed, constructed, and maintained in such a way to not effect this minimum release.

(15) Removal: Remove and lawfully dispose of all temporary diversion features after they have served their purpose. Exercise care during the removal of all diversion features to minimize turbidity in the reservoir and the adjacent stream channels;

exercise care during removal of diversion features to prevent damage to the permanent work; and repair or replace as approved by the COR any damage to the permanent work occasioned thereby, all at no additional cost to the Contracting Officer.

(16) In Section 7, Measurement and Payment, Method 1 will apply. Payment will be made as the work proceeds, after receipt of invoices from the Contractor showing percent of work performed this payment period. Up to 60 percent of the lump sum price will be paid following completion of the filtered rock toe, and surface water has been successfully diverted in accordance with the Contractor’s accepted Surface Water Diversion Plan and in compliance with the Contractor’s approved Erosion and Sediment Control Plan for a period of at least seven (7) consecutive days to the satisfaction of the COR. Up to 80 percent of the lump sum price will be paid following completion of the installation of the filtered rock toe and appurtenances, including but not limited to permanent access roads and rock lined gutter to the satisfaction of the COR. The remainder of the lump sum price will be paid when temporary Surface Water Diversion Components have been removed to the satisfaction of the COR. Total payment will be the contract lump sum price for Diverting Surface Water, regardless of actual cost to the Contractor.

(19) Items of work subsidiary to this Bid Item are:

(a) Constructing Temporary Diversions, Construction Specification 27 –

Diversions and Waterways.

(b) Excavation, Diverting Surface Water, Unclassified, Construction Specification 21 – Excavation.

(c) Earthfill, Diverting Surface Water, Construction Specification 23 – Earthfill.

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(d) Temporary Rock Riprap, Diverting Surface Water, Construction

Specification 61 – Rock Riprap.

(e) Type I Geotextile, Construction Specification 95 – Geotextile.