EARTHEN DAM 



Earthen dams are a second type of barrier. This measure is used most 

 frequently on small creeks or tributaries, but could be effectively used on 

 slightly larger water bodies if the flow rate is slow [Jess than 0.5 knots 

 (kn]j. Earthen dams are very easy to construct, using a bulldozer, dragline, 

 or backhoe. The primary objective is to allow the water to pass downstream 

 while containing the oil. Water passes through an inverted siphon or inclined 

 pipe, which is placed below the water surface (Figure 10). 



> WATER 

 FLOW 



WATER 

 FLOW 



Figure 10. Earthen dam barriers with inverted siphon and inclined 

 pipe for the containment of spilled oil. 



In summary, it should be remembered that physical barriers, whether booms 

 or dams, are intended to restrict the spread of oil and decrease contamination. 

 With regard to booms, almost anything that floats can be strung together to 

 assist in the endeavor. Items that have been used in the past with varying 

 degrees of success include bales of hay, telephone poles, and 55-gallon drums. 

 In all oil spill situations, rapid response is the key to an effective operation, 

 and containment must be accomplished as soon as possible, using the best 

 available resources. 



SKIMMERS 



Assuming that efforts to contain the discharged oil have proved success- 

 ful, recovery of the spilled oil is then begun. Removal is usually accomplished 

 with the use of mechanical devices called "skimmers." 



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