NSWC/WOL/TR 75-35 



1. Pre-test conditions 



In order to make valid comparisons on water quality data 

 before and after an explosion test and after an explosion test and 

 to establish a long-term trend, pre-test conditions of the test 

 environment should be accurately established. Extensive base-line 

 data on water quality should be compiled. 



2. Post-test conditions 



Explosion products which are expected to have the most 

 adverse effect on the environment should be selected first for 

 measurement. In addition, explosion products which are pertinent to 

 the objectives of the test program should also be examined. 

 Parameters which are relatively unimportant, but their measurements 

 can be made with very little effort, should be considered. If the 

 products are in a fixed ratio, measurements of a product that can be 

 easily obtained, can be used to estimate the quantity of others in 

 the water. 



3. Long-term monitoring 



Continuous monitoring of water quality at the test site is 

 unnecessary because underwater explosion tests are usually conducted 

 in an unconfined area. Most of the explosion products would have 

 been diluted and carried away by the water current shortly after the 

 explosion. However, periodical examination of the sediment in the 

 vicinity of the test site should be made in order to assess the degree 

 of long-term accumulation of explosion products in the sediment. 

 This would be particularly important in a shallow water site. 



The minimum number of samples collected for analyses should be 

 sufficient to fulfill the objectives of the monitoring program. 

 Multiple sampling, necessary for an adequate characterization of the 

 water body, can be reduced to single sampling as a trade off between 

 cost and accuracy. Less expensive analytical methods can be used to 

 substitute the more expensive ones for the similar purpose. 



It should be stressed that the collection of water samples from 

 underwater explosion tests presents many special problems. For 

 example, if automatic equipment is placed too close to the explosive, 

 it may be damaged by the shock wave. However, samplers and other 

 devices can be strung in a line down-current. Also, a boat can be 

 used to traverse the pool immediately following the explosion. In 

 general, the time available for the collection of meaningful data is 

 only a few minutes. 



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