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Home My WebLink About1998 Tabasco Oil PoolARCO Alaska, i—. Post Office Box 100360 Anchorage, Alaska 99510-0360 Telephone 907 276 1215 Steven V. Bross Supervisor Greater Kuparuk Area Satellite Development ATO 1148 Phone 265-6083 Fax 265-6133 April 1, 1999 Mr. Robert Christenson, Commissioner Alaska Oil and Gas Conservation Commission 3001 Porcupine Drive Anchorage, Alaska 99501 6RV e: 1998 Tabasco Oil Pool Annual Reservoir Surveillance Report Dear Mr. Christenson: 1U In compliance with Rule 11, Conservation Order No. 435, ARCO Alaska, operator of the Kuparuk River Field, is hereby submitting the annual report on the Tabasco Oil Pool. This report documents the required information pertinent to the field development and enhanced recovery operations from January through December 1998. The following is an outline of the information provided: a. A summary of the enhanced recovery project (Attachment 1). b. Voidage balance, by month, of produced and injected fluids (Attachment 2, Attachment 3). c. Analysis of reservoir pressure surveys taken in 1998 (Attachment 4). d. Results of production surveys, and any special surveys, taken on the Tabasco Oil Pool in 1998 (Attachment 5). e. Results of well allocation and test evaluation for Rule 7, and any other special monitoring (Attachment 6). f. Future development plans (Attachment 7). If you have any questions concerning this data, please contact Mike Beck at (907) 276-1215 x7285. Sincerely, Steve Bross GKA Satellite Development Supervisor ARCO Alaska, Inc. is a Subsidiary of AtlanticRichfieldCompany Attachment 1 Tabasco Oil Pool 1998 Annual Reservoir Surveillance Report Summary of the Enhanced Recovery Project Tabasco produced 484 MSTB of crude, 112 MMSCF of formation gas, and 51 MB of water during 1998. Water injection of 554 MB over the same period maintained reservoir pressure at near the initial reservoir pressure of approximately 1500 psig. The injection/withdrawal ratio was 0.91 on a reservoir barrel basis; 55 MRB net production occurred. One new producer, 2T-202, was drilled/cored, completed and produced in 1998, and an existing well, 2T-201, was converted to water injection for the 2-well, Tabasco Pilot Waterflood Tract Operation at Kuparuk River Unit Drill Site 2T. The Tabasco Pilot Waterflood Tract Operation was run from April, 1998 through October, 1998. Pressure response and water breakthrough from injection were observed. Watercut had reached 26% at year end. Development drilling for long term Tabasco operations commenced in November, 1998 and continued beyond year end, but these new development wells were not placed in service before year end. The 2T-202 full diameter core recovery was poor, but 152 percussion side wall cores were recovered from the Tabasco interval along with a variety of open hole wireline logs. The core and log data were used to improve the Tabasco reservoir description for applications such as completion designs, reservoir management, etc. The 2T-202 well was completed with an openhole gravel pack. This producer was temporarily produced with gas lift beginning on May, 11 1998. 2T- 202 produced with gas lift until December 4, 1998 when it was shut in for conversion to electric submersible pump. Prior to converting 2T-201 to injection, a production test was attempted in April 1998 with the objectives of estimating vertical permeability and characterizing solids production tendency. Mechanical problems prevented achievement of the test objectives and 2T-201 was converted to water injection on June 9, 1999. Attachment 2 Tabasco Oil Pool 1998 Annual Reservoir Surveillance Report Produced Fluid Volumes OIL GAS WATER CUM OIL CUM GAS CUM WATER MO YR STB MSCF BBL STB MSCF BBL 1 1998 0 0 0 0 0 0 2 1998 0 0 0 0 0 0 3 1998 0 0 0 0 0 0 4 1998 522 1065 17 522 1065 17 5 1998 41200 14705 151 41722 15770 168 6 1998 76749 43841 47 118471 59611 215 7 1998 79794 18395 68 198265 78006 283 8 1998 83435 14227 1593 281700 92233 1876 9 1998 34478 3233 1363 316178 95466 3239 10 1998 82466 7450 16968 398644 102916 20207 11 1998 53416 3359 19560 452060 106275 39767 12 1998 32177 5408 11620 484237 111683 51387 1998 TOTAL 484237 111683 51387 Attachment 3 Tabasco Oil Pool 1998 Annual Reservoir Surveillance Report Injected Fluid Volumes WATER GAS NGLS CUM WATER CUM GAS CUM NGLS MO YR STB MSCF MSCF STB MSCF MSCF 1 1998 0 0 0 0 0 0 2 1998 0 0 0 0 0 0 3 1998 0 0 0 0 0 0 4 1998 0 0 0 0 0 0 5 1998 0 0 0 0 0 0 6 1998 36537 0 0 36537 0 0 7 1998 105899 0 0 142436 0 0 8 1998 144329 0 0 286765 0 0 9 1998 73553 0 0 360318 0 0 10 1998 107540 0 0 467858 0 0 11 1998 76997 0 0 544855 0 0 12 1998 9390 0 0 554245 0 0 1998 TOTAL 554245 0 0 U) >. (D U) d L 7 N d L a •O Gl N d cr Q n 0 i c m a m of N n a n 0 N _T C Cl E N E a 0 U m m 0 a Q Q D n a m m m a m a m T � a m m o L 3 c ; O o J V] a C1] o N N y a $� � o Ol (O QI m � a` a 0 a a_ (� m Q✓ a` a 0 a i u O (7 N (D N C M a a` S a � � N O r O r V Ol N V V a7 N N N � Sa O N O V Orl O r N cc 2 m m °1 m m Q N C N m m o 0 m rn m rn m rn m rn m � N N N N N N 3 N N N N N Attachment 5 Tabasco Oil Pool 1998 Annual Reservoir Surveillance Report Production/Special Surveys Well Date Type Comments 2T-202 June 17, 1998 CT -conveyed Uniform oil contribution throughout gravel pack interval 3964 to P, T, Spinner 4190'MD, free gas entry at top of interval, 3964'MD. Interval 4190 to 4265'MD (TD) not logged due to fill. Test rate: 812 BOPD, 1.6% WC, 1020 SCF/STB FGOR, 525 MSCFD lift gas Attachment 6 Tabasco Oil Pool 1998 Annual Reservoir Surveillance Report Well Allocation and Test Evaluation Summary Tabasco production was metered in 1998 through the KRU IDS 2T test separator. A minimum of two well tests per month were taken on production Well 2T-202 except for November. Production down time due to an ice plug allowed completion of one well test in November, 1998. The AOGCC was notified of this problem at that time. Kuparuk PVT correlations were applied to correct Tabasco test rates from separator conditions to standard conditions by accounting for the Oil Formation Volume Factor, the Solution Gas:Oil Ratio and temperature. Use of Kuparuk PVT correlations slightly under estimated Tabasco oil production with less than 5% error. Tabasco PVT correlations were installed and used beginning in March, 1999. Production volumes were tracked through the KDGS and Setcim production monitoring systems. An allocation factor of 1.0 was applied to Tabasco production for 1998. Attachment 7 Tabasco Oil Pool 1998 Annual Reservoir Surveillance Report Tabasco Development Plan One producer was drilled and completed, and an existing well was converted to injection for Tabasco Phase 1A at Kuparuk River Unit Drill Site 2T. Development drilling for additional wells included in Phase 1 B of the Tabasco 2T development commenced in November 1998. Tabasco facilities installed to 95% complete in 1998 included: • Trunk and lateral piping for 5 production wells and 2 injection wells, with provision for up to 20 total wells. • Three-phase well test meter skid (AccuFlow) • Emergency shutdown skid • Relocation of the existing Drill Site 2A Line Heater to Drill Site 2T • Electrical platform for electrical control module, new main transformer, and variable speed drives for up to 12 electric submersible pumps • Electrical control room and variable speed drive units for 5 producers • Upgrade of the CPF-2 to Drill Site 2T electric power line from 13.8 to 34.5 kV • Associated electrical, controls, piping, and structural components to support Tabasco Phase 1 B. Phase 1 B development drilling in 1998 included one slimhole, monobore injector (perforations pending), and the surface holes for three producers (drilled and n cased). Plans for first quarter 1999 include concluding Tabasco Phase 1 B development by completing the wells drilled in 1998 and drilling and completing an additional producer. The producers will be completed with open hole gravel packs and will be equipped with electric submersible pumps for artificial lift. Pending satisfactory reservoir and well performance, additional drilling is planned in late 1999, and beyond. Current plans include drilling 3 additional producers and 2 additional injectors at Drill Site 2T in late 1999, if conventional wells are used. To complete a Tabasco Drill Site 2T conventional well development, development drilling beyond 1999 is currently envisioned as 3 producers and one injector in the year 2000, one producer in 2002, and one producer and one injector in the year 2003. Evaluation of unconventional wells for Drill Site 2T is planned. Development with unconventional wells would yield a different well count than the current conventional well based plan. Screening evaluations indicate that Tabasco development beyond Drill Site 2T is most prospective at Kuparuk River Unit Drill Sites 3H and 3G. Tabasco development beyond Drill Site 2T is dependent on Tabasco performance at Drill Site 2T and further evaluation.