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--Well Workovers
To develop additional reserves
at low costs, zones behind pipe in existing wells were evaluated using techniques
developed for the Brushy Canyon interval. The Advanced Log Analysis techniques
developed in Phase 1 have been used to complete uphole zones in a total
of thirteen NDP wells. Four wells were recompleted in 1999, which allowed
the development of economical reserves during a period of low crude oil
prices. An additional four wells were recompleted during 2000, which has
resulted in 123,462 BO and 453,424 MCFG reserves being added at a development
cost of $1.57 per B.O.E. Two wells, NDP Wells #29 and #38, were recompleted
in 2001 which has added 7,000 BO and 18 MMCFG to the reserves at a cost
of $9.70 per B.O.E. During 2002-2003, NDP Wells #1, #12, #15, and #20 were
recompleted in uphole zones which added 128,000 BO and 150 MMCFG to the
reserves at a cost of $1.65 per B.O.E. Overall, the weighted average development
cost of workovers at the NDP was $1.87 per B.O.E.
--Directional/Horizontal Wells
In Phase 2 of this project,
Strata Production Company is demonstrating that it is possible to drill
deviated/horizontal wells to develop reserves in areas not accessible
by vertical drilling (Well
Locations). Strata drilled NDP Well #36, the first directional/horizontal
well in the NDP, in 2001 (NDP
Well #36). A second directional/horizontal well, NDP Well #33, was
drilled and completed in 2002 (NDP
Well #33). Continued evaluation of results, including the additional
3-D seismic tests in Phase 2, are guiding the locations of future directional/horizontal
wells (New
Wells).
--Additional 3-D Seismic Tests
The 3-D seismic survey for the
north end of the NDP incorporated receivers located on the shore and into
selected areas of the playa lakes to record data from beneath mined areas.
In the fourth quarter of 2002, a total of 9.5 square miles was shot, with
4371 receivers and 1191 source points (Eighth
Annual). We believe that this is the first 3-D seismic survey designed
to model the Delaware formation where surface and subsurface constraints,
including voids created by underground potash mining, has been attempted.
The lower Delaware sands were successfully imaged, and the new survey
has refined the original interpretation of the NDP reservoir. Analysis
of the 3-D seismic data has identified a target in the NE/4 of Section
12 for the next deviated/horizontal well. Drilling of the NDP Well #34
began in March 2005 from the NDP Well #19 location.
--Characterization
& Simulation
A reservoir simulation was performed
to estimate the drainage area of NDP Well #36 (Seventh
Annual). The simulator was populated with structure, permeability,
and porosity derived from actual well data where available and with a
simple nearest neighbor geostatistical calculation for interwell data.
A plot of actual production versus simulator production (Simulated
Production) indicated the reservoir area attributable to NDP Well
#36 is approximately 130 acres. The reservoir simulation model is proving
to be good match to the actual production. The actual produced gas volume
appears higher than predicted and, after comparing the field volumes to
the actual sales volumes, the field volumes are 20 to 30% too high. Sales
volumes plus fuel gas used in production facilities are much closer to
the predicted gas volumes.
--Gas Processing &
Injection
The economics of processing
gas at the NDP to recover liquids and reinject lean gas for pressure maintenance
were evaluated (Eighth
Annual). Based on this analysis, the best economic course is to continue
to sell the gas outright. The additional capital cost required to install
processing and injection facilities is not justified given the estimated
future profit. However, if a processing and reinjection system had been
installed near the beginning of the NDP project some 10 years ago, the
increased oil and gas production volumes would have made better economic
sense. To date, the NDP has produced in excess of 1.25 million BO and
7.2 BCFG. These volumes, together with increased oil recoveries from pressure
maintenance, may have allowed a more rapid return and ultimately a higher
multiple on the gas processing and injection facilities.
--Production and Reserves
A production database for the
NDP was updated through August 1, 2004. These data were added to the history
of each well to update the decline curves and to project ultimate recoveries
as well as to assess the effects of interference and production strategies.
The eight wells that are part of the DOE Class III project (NDP Wells
#12, 23, 24, 25, 29, 33, 36, and 38) have produced 365,410 BO, 2.28 BCFG,
and 1,610,403 BW as of July 1, 2004. Reserves associated with the project
are summarized in the following table:

--Technology Transfer
Activities
Technology Transfer of the
data and results from the NDP project have been a major component of
the project.
Interest in this project has been high and the application of results
from the project has been useful in other Delaware fields. All of the
technology transfer activities to date in Phase 1 and Phase 2 of the
project are listed in the major section in Technology Transfer (Technology
Transfer). Strata Production Co. provided details of the NDP
deviated/horizontal wells at a PTTC workshop in Midland, TX in May
2005. A Summary of this presentation is available, and details of the
workshop are available from the Southwest
Region of the PTTC.
A final workshop
that will summarize all the results obtained during the project is being
panned for later in 2005.
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