RECOVERY--THIS NOTICE IS PROVIDED FOR INFORMATION PURPOSES ONLY. THIS OPPORTUNITY IS AVAILABLE ONLY TO CONTRACTORS UNDER W91236-09-B-0022. TECHNICAL AMENDMENT 1. REVISED DRAWING: Delete drawing H-50-14-52(2) and substitute therefore the attached new drawing H-50-14-52(2). 2. SECTION 35 20 23 Page 4 and 5, delete paragraphs 3.1, 3.1.1 and 3.1.2 and substitute therefore the following new paragraphs 3.1, 3.1.1 and 3.1.2: 3.1 REMOVAL AND PLACEMENT OF EXCAVATED MATERIAL AND REQUIREMENTS FOR USE OF GOVERNMENT FURNISHED PLACEMENT AREA 3.1.1 Government Furnished Upland Placement Area The interior and exterior of the placement area, dikes, spillboxes and associated drainage piping have been completely upgraded under separate contract prior to dredging and are expected to be adequate for the placement of dredged material proposed in this contract; however, the Contractor is responsible to insure all portions of the placement area, dikes, drainage piping and spillboxes are adequate and in proper working order before commencement of placement operations. In addition, the Contractor shall provide a steel pipe plug in the exterior opening of the 24-inch pipe culvert at the south end of the placement area for the duration of dredging and dewatering of the placement area. The pipe plug shall be manufactured for this specific use and securely installed and maintained water-tight by the Contractor in accordance with the manufacturers written instructions. The Contractor shall remove the pipe plug after dewatering of the placement area is complete. All data of the manufacturer verifying the pipe plug provided meets these requirements must be submitted to the government for approval prior to use. Any required clearing or grading of the interior or exterior of the placement area, repairs to dikes or spillboxes and associated drainage piping, clearing of debris from spillboxes or piping, and replacement of weir boards is the Contractor's responsibility and shall be provided at no additional cost to the Government with all associated costs for these items included as part of the Contractor's mobilization expenses. All materials repaired or replaced shall be in sizes and type to match existing as approved by the Contracting Officer. All trash and debris shall be removed and disposed in approved landfills at the Contractor's expense. Prior to commencing dredging operations, the weir boards shall be set at a height to assure a minimum ponding depth within the placement area of two feet measured at the spillbox. Additionally, for the duration of the contract the Contractor shall be responsible to maintain the placement area dikes and operate the spillbox by keeping spillway weirs at the correct level and free of trash and debris at all times to maintain: (1) the minimum required ponding level; (2) specified freeboard; and (3) specified effluent and other water-quality standards. The upland placement area consists of a two-part drainage system. Clarified water passing through the weir will drain into a lower tiered area of the diked placement area. All requirements of maintaining a minimum two feet of freeboard in this area shall apply as specified herein. The Contractor shall provide a suitable pump and all hydraulic pipeline to dewater this area as the work progresses. The Contractor shall be responsible to coordinate the pumping of the dredged material into the placement area with the simultaneous pumping out of the lower tiered area once clarified water has passed through the weir and reached an acceptable depth in the lower tiered area. Location of piping shall be as indicated. Type, size and location of pump shall be submitted for approval. The location of the discharge end of the effluent pipeline from the lower tiered area is approximately 2000 feet and shall conform to the detail sectional view as indicated. The discharge end of the pipeline shall be supported at a 20-degree discharge angle to the water surface with the bottom of the pipeline end at a depth of 3 feet below the water surface unless directed otherwise by the Contracting Officer. The Contractor shall provide conversion piping for the 20 degree discharge angle, flotation, and control devices as required. 3.1.2 Placement Area Use and Maintenance During Placement Operations The Contractor shall install a baffle plate, spreader pipes, pocket pipes, or other approved apparatus to the discharge end of the dredge pipeline to prevent scour and washouts within the dike and at the dredge pipe outfall. The Contractor shall employ proper dredging and placement methods to ensure that adequate ponding depth is maintained and that a minimum of two feet of freeboard, measured at the minimum containment dike elevation, is maintained at all times. The contractor shall immediately notify the COR if the freeboard drops below four-feet. The Contractor shall immediately suspend dredging and placement operations in the event of any containment dike failure, if dikes are being scoured by dredging, or if dike failure appears to be imminent. The Contractor may resume work only after suitable permanent repairs to the containment dike have been made. The Contractor shall provide at least one qualified employee during daylight and at least two qualified employees at night to monitor the Contractor's dredged material placement operations, including but not limited to the discharge of material, level of ponding, freeboard, condition of the dikes, and release of effluent from the Placement Area. Watches shall be on site during all dredged material placement operations, including dewatering of the entire placement area after the dredge stops placing material. The number of employees is expressed as a minimum; accordingly, the Contractor is responsible to provide at his expense the number of employees required to accomplish all work as indicated and specified. If during observance of his work the Contracting Officer determines the Contractors staff on site to be insufficient, additional employees in a number as directed by the Contracting Officer will be provided by the Contractor at his expense. Any damages that result from the negligence of the Contractor to properly manage the dredged material placement and properly maintain the containment dikes shall be fully repaired by the Contractor at his own expense. The Contractor shall leave the placement site in a well maintained condition. The spillbox shall be well maintained with the boards at the correct level and free of trash and debris at all times. During the progress of the work the Contractor shall perform grading and ditching as necessary to eliminate undrained areas within the containment area. At the completion of the scheduled work, the Contractor shall leave the spillbox in a well-maintained and operable condition to assure adequate site drainage.
