flushing can be expedited by turning over the remaining contaminated layer 

 with a beach-cleaner or disking machine. 



Methods for treating gravel, cobble, and shingle beaches have not been 

 perfected. Depending on the tendency of the particular oil to adhere to beach 

 materials, water flushing may be partially effective. Care must be exercised, 

 however, since flushing may drive the oil deeper into the beach. When all 

 else fails, complete removal of contaminated materials may be required. 

 Considerable effort is required to accomplish such removal, as exemplified 

 by the extensive dragline operations following the 1972 Casco Bay spill (Foget 

 1972). It should be remembered that beaches of this type represent high 

 energy environments and should experience the highest rates of natural cleansing. 

 After any operation involving extensive removal of beach material, an assess- 

 ment should be made of the impact of lost material on the littoral system. 

 Considerable amounts of material can normally be removed without significant 

 disruption of the littoral system. However, if effects are suspected or 

 observed, replacement of materials in kind and quantity is recommended. 



ROCKY SHORELINES 



RELEVANT CHARACTERISTICS 



Natural rocky shorelines are extremely variable in terms of features. 

 Generally, these types of shorelines are associated with the highest energy 

 environments. Operation of all but small portable equipment is usually impossible 

 because of the inaccessibility of the area. 



RESTORATION TECHNIQUES 



No really effective techniques have been developed to restore rocky shore- 

 lines contaminated by oil. Low- and high-pressure flushing with both hot 

 and cold water provides some degree of cleaning of both light and heavy oils, 

 but generally this flushing leaves a residual coating. Pressure and heat 

 will, of course, affect any surviving organisms. Steam-cleaning, although 

 time-consuming and costly, is effective at removing virtually everything 

 except deep stains. All of these methods merely remove oil adhering to rock 

 surfaces. They do not treat under-rock habitats and, in fact, may spread 

 surface contamination to these areas. Collection of removed oil is required. 

 At low tide, a collection trench may be dug at the foot of the rocks, and 

 recovery can be conducted with vacuum equipment, skimmers, or sorbents. If 

 collection trenches cannot be dug, booms and on-water recovery techniques 

 will be required. 



Sandblasting is not considered cost-effective or environmentally acceptable. 

 It is not recommended except for localized cosmetic treatment. 



WETLANDS 



RELEVANT CHARACTERISTICS 



Saline and brackish wetlands (or marshes) present particular restoration 

 problems. Isolated usually from human activities and highly inaccessible, 



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