Environmental Studies Program Direction:
Accelerated Deepwater Activities
Industry Perspective
A good starting place to discuss deepwater
operations is the Deep Star program, a joint industry effort involving eighteen companies
begun in 1992 and now in its third phase. Through five committees, this program focuses on
enabling development in the 3000 to 6000 ft range. Original emphasis upon seafloor systems
tied back to shallower hosts has evolved to a larger number of options.
Deep development can be contrasted with
shallow in four areas, drilling, production, processing and transportation.
- Drilling. Shallow development employs
fixed platforms with drilling and control usually on the platform. In deeper water, these
activities will migrate towards the bottom. The safety concerns are the same for shallow
and deep. Modular Offshore Development Units (MODU’s) will increase in use.
- Production. Deep and shallow are actually
quite similar with the former being a natural evolution of proven technologies from the
latter. In production, workover, and abandonment, a major concern is keeping flow lines
open. Subsea operations will see a shift in the location of hardware.
- Processing and Separation. Shallow and
deep operations will be essentially the same.
- Transportation of Fluids. Deep operations
may tie in to existing shallow pipeline systems connecting to existing infrastructure,
thereby posing no new type of environmental risk. A newer technology under consideration
for deep development is the use of tankers and floating production/storage and offloading
facilities (FPO’s and FSO’s).
Any discussion of how deep water operations
might impact the natural environment can begin with a comparison of existing shallow
concerns and anticipated deep concerns. The physical disruption caused by deep drilling
should be similar to shallow in the sense that such things as anchoring and bottom founded
structures will cause change in the benthic environment. However, operation costs mandate
that deep development proceed with a lower density of structures than now on the shelf.
Operational discharges may be fundamentally
the same shallow and deep. Increased production rates in deep water will produce a greater
produced water discharge, but one that will be comparable to or less than that now
experienced in shallow water. Traditionally, shallow well drilling has depended heavily
upon water based drilling fluids. Deep wells will depend more upon newer synthetic fluids,
and it is expected that this same technology will be adopted at all depths. Multiple wells
and horizontal wells in deep water can be expected to produce a greater volume of
cuttings. However, against this scenario of some increased discharge are two offsetting
factors. First, overall operations density should be less. Second, the dilution capacity
of a deeper water column should minimize impact.
For more information, contact James Cimato.
