ITEM P-156 TEMPORARY AIR AND WATER POLLUTION, SOIL EROSION, AND SILTATION CONTROL DESCRIPTION

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1 ITEM P-156 TEMPORARY AIR AND WATER POLLUTION, SOIL EROSION, AND SILTATION CONTROL DESCRIPTION This item shall consist of temporary control measures as shown on the plans or as ordered by the Engineer during the life of a contract to control water pollution, soil erosion, and siltation through the use of silt fence, inlet protection, and other erosion control devices or methods. The temporary erosion control measures contained herein shall be coordinated with the permanent erosion control measures specified as part of this contract to the extent practical to assure economical, effective, and continuous erosion control throughout the construction period. Temporary control may include work outside the construction limits such as borrow pit operations, equipment and material storage sites, waste areas, and temporary plant sites. MATERIALS MATERIALS. Materials for sediment and erosion control shall conform to the Maryland State Highway Administration (SHA) Standard Specifications for Construction and Materials, July 2008 Edition, and in accordance with the details on the construction drawings OTHER. All other materials shall meet commercial grade standards and shall be approved by the Engineer before being incorporated into the project. CONSTRUCTION REQUIREMENTS GENERAL. In the event of conflict between these requirements and pollution control laws, rules or regulations of other Federal, state or local agencies, the more restrictive laws, rules or regulations shall apply. The Engineer shall be responsible for assuring compliance to the extent that construction practices, construction operations and construction work are involved AUTHORITY OF ENGINEER. The Engineer has the authority to limit the surface area of erodible earth material exposed by clearing and grubbing, to limit the surface area P-156-1

2 of erodible earth material exposed by excavation, borrow and fill operations, and to direct the Contractor to provide immediate permanent or temporary pollution control measures to minimize contamination of adjacent streams or other watercourses, lakes, ponds, or other areas of water impoundment CONSTRUCTION DETAILS. The Contractor's attention is directed to GP-7.12 and Section 308 of the SHA Standard Specifications for Construction and Materials. The restrictions contained therein shall be strictly enforced, and the Contractor is cautioned, therefore, to make every effort possible to comply with these regulations. Within 14 days after the Notice of Award, the Contractor shall submit an Erosion and Sediment Control Schedule to the Engineer indicating the sequence of construction and describing the relationship between the implementation and maintenance of control, including temporary and permanent stabilization and the various stages (phases) of soil disturbance and construction. A Notice to Proceed will not be issued until this schedule is received. The sequence of construction shall, at a minimum, include a schedule and time frames for the following activities: a. Clearing for those areas necessary for installation of Perimeter Controls. b. Construction of Controls. c. Remaining clearing. d. Pavement grading and construction. e. Utility installation. f. Final grading and vegetative stabilization. g. Removal of Controls. At the Preconstruction Conference, the Contractor shall present a general overview of how they will handle Erosion and Sediment Control on the Contract. No work shall be started until the Erosion and Sediment Control schedules and methods of operations have been accepted by the Prince George s County Soil Conservation District. This includes both on-site and off-site activities. At least five working days prior to the start of work, the Engineer will initiate and conduct an Erosion and Sediment Control Field Meeting. In addition to the initial Erosion and Sediment Control Field Meeting, periodic in-field P-156-2

3 Erosion and Sediment Control Meetings shall be held during the period of this Construction Contract. The Engineer along with the Prince George s County Soil Conservation District s Inspector and Plan Reviewer and the Contractor shall review and evaluate the effectiveness of practices already installed and shall plan for the installation necessary to control proposed areas of soil disturbances. The MNCPPC is concerned with controlling erosion and sedimentation on construction sites. The Contractor shall provide adequate resources to perform the grading in a timely manner and provide and maintain the proper erosion and sediment control measures. The Engineer or his designee will be the final authority in this determination. All appropriate controls shall be installed prior to any stripping operation. Areas shall be permanently or temporarily stabilized within 72 hours from disturbance. Once the excavation or embankment reaches the bottom of the subgrade (i.e., capping material in place), those areas in which paving will be placed will be exempt from the stabilization requirements. The 3-day requirement means that the stabilization operation is complete or nearing completion. If previously stabilized areas are disturbed by the Contractor's grading operation or other activities not specifically approved by the Engineer, the cost for restabilization will be at the Contractor's expense. The most stringent requirements for stabilization under Excavation, embankment or Stabilization/Limits of Disturbance will be enforced. Disposal of excess earth material on State or Federal property requires MDE approval, otherwise materials shall be disposed of at a location approved by the appropriate local Soil Conservation District for each county or the Baltimore City Department of Public Works. The Contractor shall give particular attention to the project's construction activities that involve erosion and sediment control. The Engineer will strictly enforce erosion and sediment control measures as required by the Plans, Special Provisions, applicable referenced Standards and the Specifications. The Contractor shall become thoroughly familiar with all provisions relative to erosion and sediment control. The Contractor is advised that terminology such as "... prior to, or as soon as practicable," and "... to the extent considered desirable and practicable," shall not be interpreted to preclude or unnecessarily delay the construction or application of erosion and sediment control measures. These terms are intended to state that erosion controls must be applied as soon as it is physically possible within any construction or grading operation which removes natural ground cover or results in any unstabilized soil condition. P-156-3

4 The Contractor is also hereby notified that the Prince George s County Soil Conservation District will conduct frequent field inspections relative to sediment control compliance. If, in their judgment, noncompliance with erosion and sediment control provisions are found, their representative will immediately notify the Engineer relative to corrective action. This corrective action may require a shut-down of construction activities until such time as the noncompliance is satisfactorily corrected, and no claims to the MNCPPC will be entertained because of a shutdown of the grading operations or the entire project SILT FENCE. Silt fence shall be constructed and installed in accordance with the details shown on the plans, and in locations shown on the plans and as specified by the Engineer FILTER SOCK. Filter sock shall be constructed and installed in accordance with the details shown on the plans, and in locations shown on the plans and as specified by the Engineer STABILIZED CONSTRUCTION ENTRANCE. Stabilized construction entrance shall be constructed and installed in accordance with the details shown on the plans, and in locations shown on the plans INLET PROTECTION. Inlet protection shall be of the type indicated on the plans and shall be constructed and installed in accordance with the details shown on the plans. Inlet protection shall be installed in the locations shown on the plans and as specified by the Engineer. METHOD OF MEASUREMENT Measurement for Silt Fence, and filter sock will be made on a linear foot basis, which price shall be full compensation for furnishing, installing, maintenance of, removal of, disposal of, and for all materials, labor, tools, equipment and incidentals necessary to complete the work. All fittings and temporary inlets shall be considered incidental to the pipe installation Measurement for Stabilized Construction Entrance and Standard Inlet Protection will be made on a per each basis. Price and payment shall be full compensation for furnishing, P-156-4

5 installing, maintenance of, removal of, disposal of, and for all materials, labor, tools, equipment and incidentals necessary to complete the work. P-156-5

6 BASIS OF PAYMENT Accepted quantities of temporary water pollution, soil erosion, and siltation control work ordered by the Engineer and measured as provided in paragraph through will be paid for under: Item P Item P Item P Item P Silt Fence per linear foot Filter Sock per linear foot Stabilized Construction Entrance per each Standard Inlet Protection per each END OF ITEM P-156 P-156-6

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