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Task 1 Low Water Crossings <br /> The goal of this Task is to manage drainage of water on two of the of the old haul roads. In <br /> order to accomplish this, two (2) low water crossings are to be constructed within the Project <br /> Area, one on the Pit 4 Road, and one on the Pits 2 /3 Road. <br /> The Pit 4 Road low water crossing will be constructed immediately above the first switchback <br /> located on this road. This crossing will serve to transport water from the north to the south side <br /> of the road, and into an existing drainage swale. The other low water crossing will be <br /> constructed at the first switch back of the Pits 2/3 Road. This low water crossing will allow <br /> water to drain from the north to the south side of the road, moving the water into a pre-existing <br /> drainage swale. PROJECT MANAGER will mark the location of each low water crossing in the <br /> field prior to construction beginning. <br /> Specifications <br /> The low water crossings shall be constructed to the specifications of Figure 1, Low Water <br /> Crossing. The crossings will be constructed at about a thirty-degree (30 °) angle to the axis of <br /> the road, and will have a fall of five percent (5%) across the axis of each crossing. Ingress and <br /> egress routes shall be no steeper than 6H: 1V. The down hill slope of the crossings will be <br /> over filled to accommodate anticipated volumes of water passing through the low water <br /> crossings. The crossings shall be slightly longer than the width of the road above and below <br /> the crossing in order to capture water from the ditch above each crossing, and in order to allow <br /> the water to move into the pre-existing drainage swale below each crossing. Durable rock shall <br /> be placed at the base and on the sides of each crossing. The screened rock shall have an <br /> average size of two-inches (2"), shall be placed as a blanket throughout the length and width of <br /> the low water crossings. <br /> Durable rock rip rap shall be placed from the end of each low water crossing into the pre- <br /> existing drainage swale for a distance of thirty feet (30') below the end of each crossing. The <br /> rock placed in the pre-existing swale shall consist of two-inch (2") screened rock, overlain by <br /> clean four inch (4") rock. The rock shall be placed within these channels, which are <br /> approximately twelve inches (12") wide at the base, and onto the side slopes for an additional <br /> twelve inches (12") per side, as measured from the outside margin of the base of each channel. <br /> Durable rock is defined as rock material which gives off a ringing sound when struck with a <br /> hammer. <br /> Measurement and Payment <br /> Payment shall be made per low water crossing installed. Payment shall be made at the unit <br /> price established in the Bid Schedule, Item 1. The unit price bid will cover all costs for <br /> excavation, and rock placement per specifications. The price bid shall be considered full <br /> compensation for all equipment and materials necessary and incidental to completing the low <br /> water crossings to the specifications of this Task. Payment shall be as this Task is completed <br /> and approved by the PROJECT MANAGER. <br /> 3 <br />