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6.0 Impact Considerations Version :27.10.4 Vegetated Shoreline Habitats • Description . Vegetated shoreline habitats consist of the non-wetland vegetated banks that are common features of river systems and lakes. . Bank slopes may be gentle or steep, and the vegetation consists of grasses, bushes, or trees common to the adjacent terrestrial habitats. . The substrate is not water-saturated and can range from clay to gravel. . The banks may flood seasonally and are exposed to relatively high-energy removal processes, at least periodically. . Along undeveloped shorelines, there can be leafy litter and woody debris trapped among the vegetation. In developed areas, yards and gardens may abut the lake or river. • Predicted Oil Behavior . Vegetated shoreline habitats are considered to have medium to high sensitivity to oil spills. . They are not particularly important habitats for sensitive animals and plants, although many animals use vegetated banks for drinking, washing food, crossing bodies of water, and feeding. • Bank plants oiled during a flood period could be susceptible, especially if the flood rapidly subsides, allowing oil to penetrate into bank sediments and to contact root systems. • Stranded oil could remain in the habitat until another flood reaches the same level and provides a mechanism for natural flushing. On steep banks, the oil is likely to form a band, or multiple bands, at the waterline. . On gentle banks, there is a greater potential for oil to accumulate in pools, penetrate the substrate, and coat large areas of vegetation, thus raising the issue of shoreline cleanup. In developed urban and suburban areas, human use and aesthetics would be the main reasons for cleanup. • Response Considerations • Natural recovery may be appropriate for small spills and lighter oils where the product will not be transported to more sensitive habitats . Flooding may be appropriate for gentle banks where persistent oil has pooled, assuming the released oil can be directed towards recovery devices • Low-pressure, cold-water flushing may be effective for washing lighter oil stranded on the banks into the water for recovery . Vegetation cover minimizes the potential for sediment erosion from flushing . Sorbents are useful for recovering sheens, even for gasoline spills . Vacuum removal is most effective where access is good and substrate can support vehicles and oil is pooled Shell Supply and Distribution 6-50 Stockton Terminal FRP ©2019 Witt O' Brien's Revision Date:October, 2019