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concerning the time-dependent phenomena. The types of samples to be taken should target those 

 phenomena and biological species most likely to reveal changes in the systems; 



• detection of changes due to human activities involves all of the above considerations, but it also involves 

 study over a sufficiently long period to reveal more subtle changes associated with chronic effects. What 

 types of symptoms of human perturbations are likely to be observed? These include: physical 

 modification of substrates, hypoxia, accumulation of chemical pollutants in sediments or in biological 

 tissues, accumulation and magnification of chemical pollutants up the food chains, pathological changes 

 in tissues and organs, modification of the rates of physiological and ecological processes (photosynthesis, 

 respiration, nutrient regeneration, etc.), and reduction in populations of sensitive species and replacement 

 by more tolerant species. 



3.3.5 Proposed Monitoring Program Structure 



On the basis of our discussions, a strawman proposal was refined and areas where major design questions remain 

 were identified. 



3.3.5.1 Field Sampling Design 



The trade off in selecting monitoring sites is easy to delineate. You either study up to six regions lightly or you 

 study fewer regions more intensely. You are faced with the same trades within each region. You can study a 

 long transect lightly, or concentrate sampling heavily in a tight region. Ultimately, anticipated patterns of oil and 

 gas development both across regions and across the bathymetric transect could be used to identify the spatial 

 coverage of greatest MMS mission value. 



Sampling locations 



Zone-wise - Zones 2, 3, 4, and 5 are most relevant to oil and gas activities. Zones 1 and 6 are less 

 relevant but represent different environmental and biological types, and they would be good areas for 

 "control" studies. 



Recommendation: One complete transect for each of the zones, located near the mid-point of each 

 zone. 



• Depth-wise - Most physical and biological parameters are known to vary in relation to depth, and no 

 particular depth can provide the information necessary to interpret what is happening all across the shelf. 

 Transects are called for, and the only real questions are how many stations should be required per 

 transect, and what should be their depth distribution. 



Recommendation: Each transect should contain six stations located at depths of 30, 60, 90, 120, 150, 

 and 200 m. 



Sampling frequency 



Sampling frequency would depend upon the degree of specificity required. It is important to establish 

 the trends of time variability of the systems early in the study. Thereafter, sampling frequency could be 

 reduced. 



Recommendation: During the first three years sampling should be carried out monthly at all stations 

 in all zones. Thereafter, sampling should be conducted on a quarterly or seasonal basis. 



Sample replications 



• Replicate samples should be taken to provide a statistical basis for analysis of sampling error. The 

 exact number of replicates would vary with the particular sample type. 



