23 



2.1.4 



DETECTION OF EFFECTS AT 

 LONG-TERM PRODUCTION SITES 



Dr. James J. Kendall 



Environmental Studies Staff 



Minerals Management Service 



Gulf of Mexico OCS Region 



Since the inception of the Outer Continental Shelf (OCS) Environmental Studies Program (ESP), a stated aim 

 has been the characterization of the effects of offshore oil and gas activities either through a comparison of 

 current ecosystem data with earlier "benchmark" data or through special studies oriented toward monitoring 

 specific agents/activities or groups of agents/activities. The results of these studies have been important in 

 understanding the impacts of these activities, including both the nature and the extent of the impact. Information 

 of this sort has been used to develop mitigating measures, where needed, and to reduce or otherwise limit 

 adverse impacts due to OCS oil and gas activities. 



The study(s) to be conducted under Regional Study Number G-031/G90-F003, "Effects of OCS Development 

 and Production Activities, Northwestern Gulf of Mexico," are intended to elucidate the chronic low-level, long- 

 term stresses of developmental drilling and production activities in an area with a long history of oil and gas 

 development, production, and transportation. In particular, sites in the Western and Central Gulf of Mexico far 

 enough west to be outside the perpetual influence of the Mississippi River plume. The fiscal year (FY) 1990 

 effort is conceived as the first of several study years, to be funded in recurring 3-year cycles. The continuation 

 of this study, or suite of related studies, over a multi-year period will allow the Minerals Management Service 

 (MMS) to define these chronic low-level, long-term stresses of OCS drilling and production activities. 



This program will built on the findings of past rig and platform monitoring studies conducted in the Gulf of 

 Mexico, Pacific, and Atlantic OCS Regions, as well as other ecosystems studies in the northwestern Gulf previous 

 to, or concurrent with, this effort. This program will complement our planned study, "Long-Term Monitoring 

 at Marine Ecosystem Sites," but will differ by focusing on production sites where impacts may have occurred due 

 to offshore oil and gas industry activities, as compared to studies of natural variability at sites believed to have 

 not been impacted by such activities. 



The importance of this study to the decision-making process of the MMS is that the ESP has recently shifted its 

 focus to studies of chronic, low-level, long-term environmental impacts due to offshore oil and gas activities in 

 developed regions. Ecosystem processes and functions are also to be examined to allow for an explanation of 

 the mechanisms at work to cause the observed impacts (Aurand 1988). To learn more concerning the 

 biological/ecological effects of long-term exposures to petroleum, the MMS Pacific OCS Region has recently 

 completed a study examining the adaptations of marine organisms to chronic hydrocarbon exposure. Early in 

 1989, the MMS Gulf of Mexico OCS Region awarded a cooperative agreement to a consortium of Louisiana 

 universities, Louisiana Universities Marine Consortium (LUMCON). This award is for a five (5) year term to 

 perform projects which focus on environmental, social, or economic effects of long-term production of offshore 

 oil and gas. The study(s) to be conducted under Regional Study Number G-031/G90-F003 will differ from the 

 efforts of LUMCON in that it will provide information on the "effects" of chronic, low-level stresses at actual 

 long-term "production sites." 



Information derived from this long-term study will be important to scientists and environmental analysts 

 concerned with natural variability of the marine environment and with the effects of OCS oil and gas activities 

 on marine communities of interest or concern. Knowledge of these chronic low-level, long-term stresses will be 

 used in the design of future environmental monitoring and effects studies as well as formulation of lease 

 stipulations. This information will also be useful to various pre-lease, post-lease, and study-planning decisions. 



The activities in the development of an offshore oil and gas field may have a variety of effects on the marine 

 environment (Table 2). Effects studies have concentrated on either usual or unusual agents/activities associated 

 with offshore oil and gas development. Unusual events/activities would include disastrous events or major 

 unanticipated shifts in program activity. 



