are wide and low in slope, and are therefore suitable for mechanized operations. 

 Beaches of coarse-grained sand generally have slopes of 5 to 10 degrees and 

 poor to marginal vehicular-bearing capacity. Beaches of finer-grained sand 

 are usually lower in slope and sufficiently hard-packed to support most types 

 of motorized equipment. Gravel, cobble, and shingle beaches usually have 

 slopes in excess of 10 degrees and, as a rule, cannot support wheeled vehicles. 

 Regardless of type, dry backshore areas almost always have lower bearing 

 capacity and commonly interfere with the access of mechanized equipment. 

 Before attempting to operate mechanized equipment on a beach, one should 

 investigate the degree and variation in bearing capacity and access. 



The degree to which oil penetrates a beach is probably the single most 

 important factor governing the type of restoration. Contamination is generally 

 driven onto the beach by waves, wind, and rising tides and is deposited on 

 the foreshore by receding tides. Heavy and weathered oils and emulsions tend 

 to remain on the surface of the foreshore, with minimal vertical penetration. 

 The same material reaching the dry backshore areas may penetrate. Light oils 

 usually penetrate sands quickly and deeply. 



RESTORATION TECHNIQUES 



Historically, sorbent materials such as straw have been extensively used 

 to clean up heavier oil. Placed on the beach ahead of an approachinq slick, 

 the sorbents serve a temporary function. After the oil stands for a while 

 however, it begins to drain into the sorbent material and contaminate the 

 underlying sand. For larger spills, sorbent costs and the difficulties associated 

 with collection, recovery, and disposal of the sorbent materials are additional 

 problems. The use of sorbents may be feasible, however, for small and in- 

 accessible areas. 



A study conducted by Sartor (1970) evaluated the use of conventional 

 earth-moving equipment for restoration of oil -contaminated beaches. The 

 adaptations and techniques described have been tested and proved effective 

 on numerous occasions, and remain as probably the most environmentally acceptable 

 procedure. The selection of equipment is particularly important, since the 

 goal of the operation is to remove oil and contaminated sand with as little 

 underlying material as possible. Experience has shown that the combination 

 of motorgraders and motorized elevating scrapers is generally most effective. 

 Operating parallel to the shoreline and following the receding tide seaward, 

 the motorgraders collect layers of surface contamination into windrows. The 

 elevating scraper then recovers the windrows with minimal disruption and 

 contamination of underlying sands. From a cost-effectiveness standpoint, 

 use of bulldozers and front-end loaders is not recommended if graders and 

 scrapers are available. Bulldozers and front-end loaders usually cause more 

 mixing of contamination with underlying sands. 



Treatment of sandy beaches contaminated by light oil is more complicated 

 than the cleanup of heavier oil. Because of the increased depth of penetration 

 by light oil, complete removal of the large amount of contaminated sands is 

 usually impracticable. When the oil is concentrated near the surface (in 

 debris and as pools), it can be effectively treated by the aforementioned 

 process. The removal of the remaining material by evaporation and natural 



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