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month," Sheldon said. "Of the 70 crew members, 26 have been
with that rig 7 years."

Overcoming drilling problems

Although horizontal and multilateral drilling technologies
are in wide use around the world, Kuwait has found no major need
to use them in current drilling programs. Reservoirs like the
Burgan are world class, and applications of such technologies
would not vary production by much even if they were applied.
Even after the war, with 603 wells flowing wide open for
more than 6 months, the reservoir drop was barely measurable. "In
the 40 to 50 years of production, we've only had a 20 psi drop,"
said A. Hussain Shehab, manager of drilling operations for KOC.
However, there have been occasional stabs at drilling
horizontal wells around the country in addition to a water-injection
pilot project applied to one of Kuwait's northern fields. Also, the
interpretation of 3D seismic surveys, run over every field in
Kuwait, is in its final stages. Once these results are in, future
horizontal drilling and water injection programs will be instituted,
Shehab said.
Nonetheless, although Kuwait does not use state-of-the-art
drilling technologies, drillers face very tough drilling conditions.
There are two major types of wells in Kuwait:
1. Shallow Tertiary and Cretaceous wells
2. Deep, overpressured Jurassic wells.
One of the biggest problems is simultaneously dealing with
lost circulation zones while maintaining well control through
horizons replete with gas pockets. For instance, in the PNZ, there
is a shallow gas zone just below 600 ft. However, just above this
zone, at about 575 ft, lost circulation is a very common problem.
This problem repeats itself again and again. "At times it
becomes necessary to drill these zones blind, "Bauer said.

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