Disposition ; A brief indication of the condition of the sample at dis- 

 position, such as intact or not intact, should be recorded in the presence 

 of the courier by the person receiving the sample. 



More complete information on sample condition at disposition should be 

 included in the laboratory notebook of the receiver if the sample is not in- 

 tact when it arrives. The means by which the sample was transported should 

 also appear in the notebooks of both the sender and the receiver. When 

 possible, samples collected for spill documentation should be transported by 

 special courier, however; transport by means of registered mail, with a re- 

 turn receipt requested, is also acceptable (40 U.S.C. 1977). 



SAMPLING STRATEGY 



Sampling strategy is particularly important to analytical spill documen- 

 tation because analytical data can be no better than the samples from which 

 they are derived. The analytical laboratory charged with documentation of 

 the discharge should, therefore, participate directly in selecting and execu- 

 ting an appropriate sampling strategy. 



The selection of a sampling strategy for a specific spill site should be 

 based primarily on the chemical characteristics of the spilled substance, the 

 physical environment of the spill, and the resources available for sampling. 

 For maximum utilization of the analytical data it is imperative that the sam- 

 pling strategy selected for analytical documentation be coordinated with 

 other aspects of the spill investigation. For instance, a set of samples 

 for chemical analysis should always be taken concurrently with each set of 

 biological samples. The conditions at a spill site often change so rapidly 

 that unless biological and chemical samples are collected simultaneously, it 

 may be impossible to correlate the analytical data with the biological data 

 during the final assessment process. 



Where to Sample 



Even in a small spill the number of habitats, i.e., salt marshes, sandy 

 beaches, intertidal mud flats, etc., that are impacted can be prohibitive of 

 sampling each habitat. Ideally, at least one of each type of impacted habitat 

 should be sampled. In actual practice, however, the limitations imposed by 

 availability of resources usually results in habitats being sampled on the 

 basis of priority. The priority of each impacted habitat should be based pri- 

 marily on an evaluation of its ecological, commercial, and esthetic values. 

 Although such priority systems will vary from spill to spill due to the unique 

 characteristics of each spill incident, it is possible to start with a general- 

 ized habitat priority sampling list. For this purpose, a series of habitats 

 is listed in Table 3 in decreasing order of sampling priority. This ranking 

 is based on the ecological value of the habitat and on the potential ability 

 of the habitat to cleanse itself following a spill incident. The high-energy 



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