Common use of Sediment Clause in Contracts

Sediment. In conjunction with instream effectiveness monitoring and trends monitoring, PALCO will monitor data on instream sediment levels, channel morphology, stream bed aggradation/degradation, and biological metrics sensitive to sediment (e.g., invertebrate diversity). PALCO will assess the effectiveness of the sediment control measures by monitoring sediment production rates from roads and hillslopes. In this way, PALCO will detect any shortcomings in sediment control measures earlier than if the company depended only on instream conditions. PALCO will institute alternate management approaches to address identified shortcomings through the adaptive management process. PALCO will conduct sediment source inventories as part of the watershed analysis process for each hydrologic unit. These studies will provide baseline data on the number, location, and size of sediment sources on the ownership. In addition, these studies will provide sediment budgets identifying the amount of sediment being delivered to waters from different sources. Within five years of completing the baseline sediment studies, PALCO will conduct followup studies. These will determine the extent to which these sediment sources remain active and new sources develop (e.g., how many slides have occurred in the interim), their relationship to management activities, and how the rates of management-related surface erosion and landslides compare to the rates in the baseline period. PALCO will continue to inventory surface erosion within harvest units, bank erosion, new landslides, and road-related failures as they occur. These followup studies will continue to be completed at five-year intervals in conjunction with the watershed analysis revisitations for the life of the PALCO Aquatics Conservation Plan. Hillslope and instream effectiveness monitoring and trends monitoring will provide the necessary information for determining how the PALCO Aquatics Conservation Plan affects sediment delivery to waters. In addition, because the followup studies will examine the relationship between management and sediment production, PALCO will use study results as guidance on how to modify management activities, if necessary, to reduce sediment production through the adaptive management process. Sediment parameters are perhaps the most difficult on which to conduct effectiveness monitoring. Given this difficulty, PALCO will modify its approach for determining the effectiveness of sediment control measures as new data and scientific results become available.