Figure 7. Nesting sea turtle. 

 6. Water and Sediment Quality . 



Problems with anoxic sediments and nutrient release in the nearshore zone 

 of a high-energy beach as a result of beach nourishment do not appear to be 

 major because the fine materials that are high in organics are generally moved 

 offshore and sulfides are rapidly oxidized. The material remaining on the 

 beach is usually similar or larger in grain size to that before nourishment. 

 High-energy beaches are usually composed of coarse material that allows oxy- 

 genated water to penetrate, preventing the accumulation of sulfides and 

 saturating the sediment pore space with oxygen (Cox, 1976) . Although some 

 nutrients may be released into the water as a result of nourishing the beach, 

 they are usually rapidly diluted because of the mixing process. Reilly and 

 Bellis (1978) reported on the use of dredged material from a navigation 

 channel that contained fine material and clay high in organics for beach 

 nourishment. They noted that the release of the fine sediments from the beach 

 temporarily inhibited the reestablishment of the beach macrofauna. However, 

 CERC's studies of using nourishment materials from offshore that is similar to 

 the beach sediments did not find these problems with suspended sediments, anoxic 

 sediment, or excess nutrients. To minimize potential problems, sediments used 

 for beach nourishment should closely match the composition of the natural beach 

 sediments, have a low percentage of fine material, and be low in organic 

 content. McLachlan, et al. (1981) cautioned that because of the species rich- 

 ness of the beach environment and the cellular circulation patterns nearshore, 

 the beach system may be more sensitive to effluents than is readily apparent. 



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