The wind and the sea state are primary influences on the second type 

 of failure, which stems from the splashover of the boom. Splashover is directly 

 affected by boom design, freeboard height, angle of approach of waves to the 

 boom, and the size and interval of the waves. Any combination of these factors 

 causes the oil to go over the top of the boom. The solution, again, is site- 

 specific, and the amount and direction of movement of the boom to minimize 

 this splashover should be determined on a case-by-case basis. In choppy sea 

 conditions, some oil will probably spill over, but there is no need for alarm 

 unless large quantities are being lost. 



Regardless of the type used, booms can be effective only if positioned 

 or deployed in a manner consistent with local conditions. 



The most valuable element in boom deployment is a sound working knowledge 

 of local waterways. Knowledge of currents, tides, natural catch areas, water 

 depth, etc., is invaluable in effecting a more rapid response. A second 

 element necessary for timely, effective deployment is the availability of 

 ready support equipment. If the water body is large enough to require a boat 

 for boom deployment, it is important to have available some sort of towing 

 bridle that will place the strain on the tension member. 



The following examples demonstrate various techniques that are widely 

 used to contain oil with booms under different stream conditions (Figures 

 5, 6, and 7). The illustrated solution is not always effective. In the case 

 of most rivers, currents usually subside at or near the banks. Because of 

 reduced flow in these areas, some containment can normally be expected near- 

 shore. As can be seen, all of these deployment techniques require the securing 

 of an anchor on the leading edge of the boom. A recommended method for anchoring 

 the boom is shown in Figure 8. 



COLLECTION 

 POINT 



Figure 5. Small river with moderate depth of 15 to 20 ft 

 (4.6 to 6.1 m) and slow current of 1.0 to 1.5 kn (1.8 

 to 2.8 km/h). 



73 



