INTRODUCTION 
This study was designed to establish the concentrations of trace metals 
in sediments prior to drilling on Georges Bank and to monitor the changes in 
concentrations that could be attributed to petroleum-exploration activities. 
Some of the specific questions addressed were (1) Where do discharged drilling 
muds accumulate on Georges Bank; (2) How much do trace metals increase as a 
result of accumulating drilling mud; and (3) In areas where drilling-mud 
components increase, how long do they remain at an elevated concentration 
after the drilling is completed? 
This U.S. Geological Survey (USGS) study supports the main thrust of the 
Georges Bank Monitoring Program, that is, to evaluate potential adverse 
effects of drilling effluents on bottom-dwelling organisms. The other studies 
(and contractors) within the Georges Bank Monitoring Program include (1) the 
analysis of benthic infauna (Battelle New England Laboratories and the Woods 
Hole Oceanographic Institution), (2) the analysis of hydrocarbons in bottom 
sediments and the analysis of hydrocarbons and trace metals in benthic fauna 
(Scientific Applications, Inc.), and (3) the analysis of previous benthic 
infauna samples from Georges Bank (Taxon, Inc., Michael and others, 1983). 
The concentrations of trace metals and hydrocarbons in commercially important 
species of fish and shellfish on Georges Bank have been determined in ongoing 
programs conducted by the National Oceanic and Atmospheric Administration 
(Cooper and others, 1981; Cooper and others, 1983). This report is based on 
data generated by the USGS during all three years of the program. Only the 
data generated in the third year is tabulated in this report. Tabulation and 
interpretation of data obtained during year one and year two are contained in 
final reports for each year (Bothner and others, 1982, 1983). 
