Specifications include, but are not limited to: STRUCTURE (4-10' X 8' CIP BOX CULVERT) & APPROACH GRADING. Construction activities within the stream, along the stream banks, and in areas that drain into the stream will not be allowed unless comprehensive and effective Best Management Practices (BMPs), that will prevent sediment, fuels, chemicals, concrete wash water, and other pollutants from entering into the stream, are in-place and functioning properly. Erosion and sediment controls shall be maintained in good working condition until vegetation is restored to 70% of the pre-disturbance condition. Erosion and sediment controls implemented shall be those appropriate for the specific site conditions. Fill material shall not be placed below the ordinary high water elevation except as directed by the plans or as allowed by the United States Army Corps of Engineers 404 permit. Construction activities shall not produce sediment discharges that increase stream turbidity (i.e., water clarity) by more than 50 Nephelometric Turbidity Units (NTU) over the background turbidity level. Construction methods that produce sediment discharges exceeding this turbidity standard shall cease and may resume only after the Engineer has approved an acceptable plan. The Contractor shall immediately notify the Engineer if it is suspected that stream turbidity has been increased. Turbidity will be monitored during all stages of the project. An emphasis will be placed on monitoring construction actives causing disturbance to the stream channel. 1. Turbidity Meter and Maintenance: Measurements shall be taken by the Engineer with a Global Water WQ 770 turbidity meter or equivalent, supplied by the Engineer. Turbidity meters shall be maintained and operated in accordance with manufacturer recommendations. 2. Definition of Turbidity Sample: A turbidity sample shall be defined as the average of five measurements taken at a sampling location. 3. Obtaining a Turbidity Sample: To obtain a turbidity sample, the sensor of the turbidity meter shall be submerged in the stream and allowed to run continuously for at least one minute before taking the first turbidity measurement. Subsequent turbidity measurements shall be taken at thirty second intervals until five measurements have been obtained. Turbidity measurements shall be taken by the Engineer or a designated representative. Turbidity samples shall be taken in accordance with manufacture recommended procedures.