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Home My WebLink About2015 Greater Point McIntyre Area Lisburne Oil Pool Page 1 ASR for Apr ’15 – Mar’16 Prudhoe Bay Unit Lisburne Oil Pool 2016 Annual Reservoir Surveillance Report This Annual Reservoir Report for the period ending March 31, 2016 is submitted to the Alaska Oil and Gas Conservation Commission for the Lisburne Oil Pool in accordance with commission regulations and Conservation Order 207A. This report covers the period from April 1, 2015 through March 31, 2016. A. Reservoir Management 1. Summary Oil production and reservoir management activity in the Lisburne Oil Pool continues under gas cap expansion supported by gas injection at LGI pad and water injection at L5-29. In the Central area, pressure support is supplemented by weak aquifer influx. Pilot seawater injection projects have been on-going in the central Alapah (NK-25), the southern periphery Wahoo (04-350) and the mid-field Wahoo (L5-13 & L5-15) areas. Production and injection volumes for the 12-month period ending March 31, 2016 are summarized in Table 1. Oil production volumes include allocated crude oil, condensate and NGL production. 2. Reservoir Pressure Surveys W ithin the Pool A summary of reservoir pressure surveys obtained during the reporting period is shown in Table 2. 3. Results and Analysis of Production Logging Surveys There were two production logs obtained from Lisburne wells during the reporting period. Production logs for April 1, 2015 through March 31, 2016 are shown in Table 3. B. Development 1. Enhanced Recovery Projects a. L5 Gas Cap Water Injection Surveillance (C.O. 207A) The L5 GCWI pilot project commenced injection in July of 2008. The initial injection rate was 2 mbd, and over time has been gradually increased to approximately 17 mbd. As of March 31, 2016, the cumulative Lisburne Oil Pool Page 2 ASR for Apr ’15 – Mar’16 volume of seawater injected in L5-29 was 22,072 mbbls. The L5-29 pilot injection to date has demonstrated positive results with likely injection water breakthrough occurring in three offset producer wells (L5-28, L5-33 & L5-36). Pressure response has also been observed in offset wells. Three pressure fall-off (PFO) tests have been conducted in the L5-29 gas cap water injection well. The PFO analyses show a constant pressure boundary, and skin values of between -3.6 and -3.8. Based on these results, it is inferred that no fracture extension is occurring. Offset well annuli pressures are reported monthly to the Commission by the BP North Slope Well Integrity Engineer via the Monthly Injection Report sent to the AOGCC. b. Waterflooding Pilot Projects A review of the Lisburne development plan identified water injection as a mechanism to provide additional pressure support in the Lisburne reservoirs. A grass roots injection well, 04-350, was completed on the southern periphery of the Wahoo Formation in November 2011 and has injected 3,476 mbbls of seawater as of March 31, 2016. Seawater production has been observed in offset L3-22 during the reporting period. Another pilot water injection project has been undertaken in the mid-field area. Wahoo production wells L5-15 and L5-13 were converted to seawater injection service in March 2013. As of March 31, 2016 the cumulative volume of seawater injected in both these wells was 5,597 mbbls. No confirmed offset producer well response has been observed to date. In addition, a pilot water injection project into the Alapah Formation has been initiated from the Niakuk Heald Point pad. Alapah producer NK-25 was converted to seawater injection service in March 2013 and has injected 4,208 mbbls of seawater as of March 31, 201 6. Offset producer well pressure response and seawater production have been observed during the reporting period. 2. Well Activity: Drilling Rig Three wells: L1-23, L3-03 and L3-10, were drilled and completed into the Lisburne Formation during the reporting period. 3. Well Activity: Non-Rig Twenty six Lisburne wells had a total of thirty one rate-adding non-rig interventions performed during the reporting period. These rate-adding Lisburne Oil Pool Page 3 ASR for Apr ’15 – Mar’16 interventions included perforations, acid stimulations, hydraulic fracture stimulations, gas-lift work, profile modifications, tubing patches, casing repairs and surface component repairs. 4. Other Activity Work was completed in April 2015 that allowed for L5 production to be rerouted through the Niakuk commonline, returning the pad back to full service due to line wall loss in the L5 production export line. L1 crude heater repair work began in 2015 and is expected to be completed in 2016. Other various scheduled plant and pipeline repairs and modifications were completed to protect or enhance production. Support Facilities Lisburne shares North Slope infrastructure with the Point McIntyre and Niakuk Fields. Six wells from the IPA can produce to the LPC as part of the L2 Re -route Project: L2-03A, L2-07A, L2-08A, L2-11A, L2-13A and L2-18A. Production Allocation The production of oil and gas, including those hydrocarbon liquids reported as NGLs, is allocated to the Lisburne Participating Area in accordance with conditions approved by the Alaska Department of Natural Resources, Alaska Department of Revenue, and Alaska Oil and Gas Conservation Commissi on. There is a test separator at each Lisburne Drill Site. 5. Future Development Plans (C.O. 207) Lisburne Pool oil is predominantly processed at the Lisburne Production Center which began permanent operation in December 1986. There are currently 83 development wells in the Lisburne Oil Pool. Future development plans are discussed in the 2015 Lisburne Plan of Development filed with the Division of Oil and Gas of the Alaska Department of Natural Resources, which the Commission received on June 30, 2015. T he Commission will be copied when the 2016 update of the Lisburne Plan of Development is filed with the Division. Lisburne Oil Pool Page 4 ASR for Apr ’15 – Mar’16 Tables & Figures Oil + NGL Gas Water Oil + NGL Gas Water Monthly Cum Monthly Cum Date mstbo mmscf mbw mstbo mmscf mbw mmscf bscf mbw mbw 4/1/2015 175.06 3,897 148 176,997 1,925,441 57,144 4,768 1,937,117 3,001 40,625 5/1/2015 131.34 2,850 92 177,128 1,928,291 57,236 3,496 1,940,613 3,092 43,716 6/1/2015 129.90 2,925 119 177,258 1,931,216 57,355 2,838 1,943,452 1,910 45,627 7/1/2015 70.94 1,408 41 177,329 1,932,624 57,396 2,037 1,945,489 2,249 47,876 8/1/2015 78.43 1,900 94 177,408 1,934,524 57,490 2,609 1,948,098 2,737 50,613 9/1/2015 101.84 2,816 30 177,510 1,937,340 57,521 3,405 1,951,503 1,920 52,533 10/1/2015 109.11 3,616 79 177,619 1,940,956 57,600 3,222 1,954,725 2,636 55,169 11/1/2015 193.75 3,851 185 177,812 1,944,807 57,785 5,095 1,959,820 2,191 57,360 12/1/2015 315.90 4,987 336 178,128 1,949,794 58,121 4,609 1,964,429 2,757 60,117 1/1/2016 340.60 5,899 357 178,469 1,955,693 58,478 3,913 1,968,342 2,733 62,849 2/1/2016 247.95 4,219 208 178,717 1,959,912 58,686 4,510 1,972,852 2,851 65,701 3/1/2016 243.98 4,560 159 178,961 1,964,472 58,846 4,523 1,977,374 2,860 68,561 Table 1 - Lisburne Monthly Production& Injection Volumes Monthly Production Cumulative Production Gas Injection Water Injection Table 2 - Lisburne Pressure data April 1, 2015 to March 31, 2016 Well Name Survey Date Pressure (psi) (Datum = 8900' SS) L2-28 4/14/2015 3483 L2-24 4/15/2015 2586 NK-26 4/26/2015 2647 L3-10 5/4/2015 2961 L5-08 5/23/2015 3144 L5-23 5/25/2015 3686 L5-28A 7/7/2015 3732 L5-05 7/9/2015 3265 L5-36 7/26/2015 3816 L1-01 8/25/2015 3113 04-350 9/12/2015 3412 L5-12 10/7/2015 3259 L3-10 10/23/2015 3080 L1-23 10/24/2015 3562 L3-11 10/30/2015 2559 L3-03 11/7/2015 3247 L1-09 12/31/2015 3362 L1-15A 1/15/2016 3398 L3-24 1/16/2016 3412 L4-10 1/16/2016 2868 Lisburne Oil Pool Page 5 ASR for Apr ’15 – Mar’16 Table 3 - Lisburne Logging Comments/Interpretation Production logs obtained for the following wells: L3-03 L3-10 Lisburne Oil Pool Page 6 ASR for Apr ’15 – Mar’16 Figure 1 - Lisburne Location and Status Map Niakuk Oil Pool Page 1 ASR for Apr ’15 – Mar ‘16 Prudhoe Bay Unit Niakuk Oil Pool 2016 Annual Reservoir Surveillance Report This Annual Reservoir Surveillance Report is submitted to the Alaska Oil and Gas Conservation Commission for the Niakuk Oil Pool in accordance with commission regulations and Conservation Order No. 329A. This report summarizes the period from April 1, 2015 through March 31, 2016. A. Reservoir Management 1. Summary Oil production and reservoir management activity in the Niakuk Oil Pool continues under waterflood. Reservoir management activity in the Niakuk Oil Pool includes: 1) selective perforating and profile modifications to manage conformance of the waterflood, 2) production and injection profile logging to determine current production and injection zones for potential profile modifications, material balance calculations, and effective full field modeling, 3) pressure surveys to monitor flood performance and 4) analysis of production, Gas Oil Ratio, and Water Oil Ratio trends to highlight poorer performing wells for possible intervention activity. Production and injection volumes and resultant voidage data by month for the 12-month period ending March 31, 2016 are summarized in Tables 1 and 2. 2. Reservoir Pressure Surveys Within the Pool A summary of reservoir pressure surveys obtained during the reporting period is shown in Table 3. 3. Results of Production Logging, Tracer and Well Surveys (C.O. 329A Rule 9d) No production logs were run during the reporting period. No tracer surveys were performed during this reporting period. B. Development 1. Enhanced Recovery Projects a. Progress of Niakuk Waterflood Project Implementation and Reservoir Management Summary (C.O. 329A Rule 9a) The Niakuk waterflood was started in April 1995, in conjunction with the commissioning of permanent facilities at Heald Point, using water from the Niakuk Oil Pool Page 2 ASR for Apr ’15 – Mar ‘16 Initial Participating Area Seawater Treatment Plant. Produced water from the Lisburne Production Center was used between August of 2000 and May 2004. Conversion to seawater injection was completed in September 2004 , and s eawater injection continues throughout this reporting period. All producing segments (1, 2/4, and 3/5) are receiving pressure support from water injection. There are 6 active injectors in the Niakuk Pool with an average total injection rate of approximately 25 mbd for the reporting period. The current injection strategy is to maintain balanced voidage replacement in each segment. b. Voidage Balance of Produced and Injected Fluids (C.O. 329A Rule 9b) Tables 1 and 2 detail hydrocarbon production, water injection and resultant voidage data by month for the reporting period. c. Analysis of Reservoir Pressure Surveys Within the Pool (C.O. 329A Rule 9c) Table 3 shows results from the 2015/2016 reservoir pressure surveys. The pressures in Segments 2/4, 1, and 3/ 5 are generally managed with the original reservoir pressure of approximately 4500 psi as a target/maximum, and the bubble point pressure of 4200 psi as a minimum. 2. Special Monitoring: NK-43 Well (C.O. 329A Rule 9e) NK-43 is a commingled producer which produces from both the Kuparuk and Sag River reservoirs. The AOGCC approved co-mingled production in NK-43 with production allocated to each reservoir via geochemical analysis in Conservation Order 329B on December 7 , 2006. An oil sample was taken from NK-43 during the reporting period, for geochemical analysis to confirm production allocation splits between the Sag River and Kuparuk reservoirs. This analysis shows that 100% of oil production in NK -43 is from the Kuparuk. 3. Well Activity: Permanent production facilities at Niakuk were commissioned in March 1995. There have been 29 development wells drilled into the Niakuk Oil Pool through the end of the reporting period. Niakuk Oil Pool Page 3 ASR for Apr ’15 – Mar ‘16 During the reporting period NK-07A was repaired with a quick-connect liner latch system deployed without a rig to repair a casing leak. The packer leak on NK - 20A was repaired with a packer squeeze. An extended coil campaign was completed to mill scale on NK-08A, NK-09, NK-29, and L5-34. 4. Future Development Plans (C.O. 329A Rule 9f) Future development plans are discussed in the 2015 Niakuk Plan of Development filed with the Division of Oil and Gas of the Alaska Department of Natural Resources, which the commission received on June 30, 2015. The commission will be copied when the 2016 update of the Niakuk Plan of Development is filed with the Division. Niakuk Oil Pool Page 4 ASR for Apr ’15 – Mar ‘16 Tables and Figures Table 1 - Niakuk Monthly Production & Injection Summary Produced Produced Produced Injected Injected Injected Cum Prod Cum Prod Oil Gas Water Gas Water MI Oil Gas mstb mmscf mstb mmscf mstb mmscf mstb mmscf Apr-15 30 41 40 765 0 785 0 94,135 83,983 May-15 31 42 107 781 0 690 0 94,177 84,091 Jun-15 30 40 73 758 0 624 0 94,217 84,164 Jul-15 31 5 12 117 0 1,024 0 94,222 84,176 Aug-15 31 15 20 192 0 860 0 94,237 84,195 Sep-15 30 34 66 464 0 625 0 94,271 84,262 Oct-15 31 39 79 609 0 1,018 0 94,310 84,340 Nov-15 30 27 55 539 0 792 0 94,337 84,395 Dec-15 31 49 101 825 0 754 0 94,386 84,496 Jan-16 31 46 90 769 0 812 0 94,432 84,586 Feb-16 29 24 35 372 0 644 0 94,456 84,621 Mar-16 31 43 90 804 0 572 0 94,498 84,711 Apr-11 0 0 0 0 0 0 0 0 0 Year 366 405 767 6,996 0 9,200 0 0 0 Table 2 - Niakuk Monthly Voidage Balance Produced Produced Produced Injected Injected Injected Net Res. Oil Gas Water Gas Water MI Voidage mrvb mrvb mrvb mrvb mrvb mrvb mrvb Apr-15 30 54 8 773 0 793 0 41 May-15 31 55 53 789 0 697 0 200 Jun-15 30 52 31 765 0 630 0 217 Jul-15 31 7 6 118 0 1,034 0 -903 Aug-15 31 19 7 194 0 869 0 -649 Sep-15 30 44 29 469 0 631 0 -89 Oct-15 31 51 35 615 0 1,029 0 -328 Nov-15 30 35 25 545 0 800 0 -195 Dec-15 31 64 45 834 0 762 0 181 Jan-16 31 60 39 777 0 820 0 56 Feb-16 29 31 13 375 0 650 0 -231 Mar-16 31 55 41 812 0 578 0 331 Apr-11 Year 366 526 332 7,066 0 9,292 0 -1,368 Note: Negative Net Reservoir Voidage indicates IWR>1 Note: Monthly Production/Injection/Voidage/Pressure data (Tables 1 & 2) do not include the production results from NK-38A well drilled to the Ivishak (Raven) Formation or injection from the NK-65A injector which supports NK-38A. They are subject to a separate Raven Oil Pool Annual Reservoir Report. Niakuk Oil Pool Page 5 ASR for Apr ’15 – Mar ‘16 Table 3 – 2015 – 2016 Pressure Survey Data Table 3 - Niakuk Pressure data April 1, 2015 to March 31, 2016 Well Name Survey Date Pressure (psi) (Datum = 9200' SS) NK-09 7/6/2015 4450 NK-27 7/7/2015 4382 NK-61A 7/9/2015 4367 L5-34 7/19/2015 4383 NK-22A 7/25/2015 4823 NK-42 7/28/2015 4631 NK-21 8/21/2015 4511 Point McIntyre Oil Pool Page 1 ASR for Apr ’15 – Mar ‘16 Prudhoe Bay Unit Pt. McIntyre Oil Pool 2016 Annual Reservoir Surveillance Report This Annual Reservoir Report for the period ending March 31, 2016 is submitted to the Alaska Oil and Gas Conservation Commission for the Pt. McIntyre Oil Pool in accordance with Commission regulations and Conservation Order 317B. This report summarizes the period between April 1, 2015 and March 31, 2016. A. Reservoir Management 1. Summary Production and injection volumes for the 12-month period ending March 31, 2016 are summarized in Table 1. Total Pt. McIntyre hydrocarbon liquid production (oil plus NGL) averaged 15.4 mbd. Current well locations are shown in Figure 1. The dominant oil recovery mechanisms in the Pt. McIntyre Oil Pool are waterflooding and miscible gas injection in the down-structure area north of the Terrace Fault and gravity drainage in the up-structure area referred to as the Gravity Drainage (GD) Area. Gas injection commenced in the gas cap with field startup to replace voidage and promote gravity drainage. The waterflood was in continuous operation during the reporting period with 16 wells on water injection. 2. Progress of Enhanced Recovery Project Implementation and Reservoir Management Summary (Rule 15 a) During the 12 month period from April 2015 – March 2016, a total of 17.5 BCF of MI (miscible injectant) was injected into P2-16 (5.4 BCF), P2-28 (1.2 BCF), P2-29 (1.5 BCF), P2-42 (3.2 BCF), and P2-46 (6.2 BCF). Ten of the 15 waterflood EOR patterns have had MI injection to date. 3. Voidage Balance by Month of Produced and Injected Fluids (Rule 15 b) Monthly production and injection surface volumes are summarized in Table 1. A voidage balance of produced fluids and injected fluids for the report period is shown in Table 2. As summarized in these analyses, monthly voidage is targeted to be balanced with injection. 4. Analysis of Reservoir Pressure Surveys within the Pool (Rule 15 c) Point McIntyre Oil Pool Page 2 ASR for Apr ’15 – Mar ‘15 Reservoir pressure monitoring is performed in accordance with Rule 12 of Conservation Order 317B. A summary of reservoir pressure surveys obtained during the reporting period is shown in Table 3. 5. Results and Analysis of Production & Injection Logging Surveys (Rule 15 d) There were two production logs and no injection log obtained from Pt McIntyre wells during the reporting period. Production and injection logs for April 1, 2015 thru March 31, 2016 are shown in Table 4. 6. Results of Any Special Monitoring (Rule 15 e) No special monitoring was performed during the reporting period. B. Development (Rule 15 f & g) 1. Well Activity: There currently are a total of 26 well penetrations drilled from DS -PM1 including sidetracked, P&A and suspended wells. There are a total of 76 well penetrations drilled from DS-PM2. An additional water/MI injector (P1-25) is located at the West Dock staging area. During the reporting period, the scale management program continued for Pt Mac wells and included regular scale inhibition treatments. P1-14 was restored to injection with a rig work-over. 2. Other Activities a. Pipelines i. Figure 2 shows the existing pipeline configuration together with the miscible injectant distribution pipelines from LPC and CGF to the Pt. McIntyre drill sites. ii. Pt. McIntyre production is processed at the LPC, and between March of 2004 and November 2011 was also processed at the GC- 1 Gathering Center facilities via a 36” three phase line from PM2 to GC-1. PM1 wells can only flow to the LPC. During this period all wells at drillsite PM2 could be flowed to either the LPC (high pressure system) or to GC-1 (low pressure system). As a result of this connection, wellhead pressures were lowered for the PM2 wells flowing to GC-1 by approximately 400 psi and utilized approximately 80 MB/D of available water handling capacity at GC - 1. On November 12th 2011, the 36” line from PM2 to GC-1 was shut-in due to the integrity status of the line. Production is currently Point McIntyre Oil Pool Page 3 ASR for Apr ’15 – Mar ‘15 limited by both gas and water handling limits at the LPC facilities. Production from some areas of the field is also limited by injection well capacity and reservoir management constraints. Repair of the pipeline is underway. b. Produced Water During the 12-month reporting period, the LPC continued to provide produced water for injection at Point McIntyre. Additional produced water is provided from FS1 to LPC for injection at Pt. McIntyre. c. Support Facilities Pt. McIntyre will continue to share North Slope infrastructure with the Lisburne Participating Area ("LPA") and the Initial Participating Areas to minimize duplication of facilities. 3. Future Development Plans (C.O. 317B) Permanent production facilities at Pt. McIntyre were commissioned in 1993. There have been 97 development wells drilled into the Pt. McIntyre Oil Pool through the end of the reporting period. Future development plans are discussed in the 2015 Pt. McIntyre Plan of Development filed with the Division of Oil and Gas of the Alaska Department of Natural Resources, which the Commission received on June 30, 2015. The Commission will be copied when the 2016 update of the Pt. McIntyre Plan of Development is filed with the division. Point McIntyre Oil Pool Page 4 ASR for Apr ’15 – Mar ‘15 Tables and Figures Table 1 - Pt McIntyre Monthly Production & Injection Summary Produced Produced Produced Injected Injected Injected Cum Prod Cum Prod Oil Gas Water Gas Water MI Oil Gas mstb mmscf mstb mmscf mstb mmscf mstb mmscf Apr-15 30 441 5,815 2,630 3,994 3,198 1,272 455,878 1,286,511 May-15 31 427 5,318 2,627 4,081 3,387 1,667 456,306 1,291,829 Jun-15 30 389 4,481 2,177 3,531 3,095 1,646 456,695 1,296,310 Jul-15 31 469 5,642 3,480 4,130 2,368 1,134 457,163 1,301,952 Aug-15 31 412 4,590 2,743 3,541 1,822 950 457,576 1,306,542 Sep-15 30 488 5,729 3,180 3,789 3,013 1,070 458,064 1,312,271 Oct-15 31 480 5,309 3,227 4,335 3,054 1,058 458,544 1,317,580 Nov-15 30 434 6,300 2,471 4,669 2,743 1,472 458,978 1,323,880 Dec-15 31 432 4,521 2,762 5,058 3,285 1,988 459,411 1,328,401 Jan-16 31 446 4,115 3,092 5,241 3,563 1,776 459,857 1,332,516 Feb-16 29 408 5,180 2,986 4,533 3,675 1,878 460,265 1,337,696 Mar-16 31 406 5,453 2,894 4,980 3,773 1,607 460,671 1,343,149 Apr-11 0 0 0 0 0 0 0 0 0 Year 366 5,234 62,453 34,268 51,883 36,976 17,518 0 0 Table 2 - Pt McIntyre Monthly Voidage Balance Produced Produced Produced Injected Injected Injected Net Res. Oil Gas Water Gas Water MI Voidage mrvb mrvb mrvb mrvb mrvb mrvb mrvb Apr-15 30 614 3,739 2,669 2,725 3,246 789 262 May-15 31 594 3,407 2,666 2,785 3,437 1,034 -588 Jun-15 30 541 2,856 2,210 2,409 3,141 1,021 -965 Jul-15 31 652 3,607 3,532 2,818 2,404 703 1,866 Aug-15 31 574 2,918 2,784 2,416 1,849 589 1,422 Sep-15 30 679 3,656 3,227 2,586 3,058 664 1,256 Oct-15 31 668 3,374 3,275 2,958 3,100 656 603 Nov-15 30 604 4,074 2,508 3,186 2,784 913 303 Dec-15 31 601 2,861 2,803 3,452 3,335 1,233 -1,754 Jan-16 31 621 2,576 3,138 3,576 3,616 1,101 -1,958 Feb-16 29 568 3,323 3,031 3,093 3,730 1,164 -1,066 Mar-16 31 565 3,510 2,937 3,398 3,830 996 -1,212 Year 366 7,280 39,900 34,782 35,402 37,531 10,861 -1,832 Note: Negative Net Reservoir Voidage indicates IWR>1 Point McIntyre Oil Pool Page 5 ASR for Apr ’15 – Mar ‘15 Table 3 - Pt. McIntyre Pressure data April 1, 2015 to March 31, 2016 Well Name Survey Date Pressure (psi) (Datum = 8800' SS) P2-40 4/12/2015 4068 P2-35 4/16/2015 4050 P2-13 4/27/2015 3851 P2-31A 4/30/2015 4011 P2-18 5/1/2015 4050 P2-04 5/27/2015 3859 P2-45B 6/21/2015 4371 P2-58 11/26/2015 3911 P2-42 12/4/2015 3952 P1-21 1/23/2016 3884 P1-05 1/24/2016 3945 P2-08A 1/25/2016 4116 P2-21 1/26/2016 3953 P1-13 1/31/2016 3941 P1-20 2/1/2016 3769 P2-36A 2/10/2016 4170 P1-24 3/27/2016 3946 Table 4 – Pt McIntyre Logging Comments/Interpretation Production logs obtained for the following wells: P2-18 P2-58 No gas cap monitoring logs were obtained Point McIntyre Oil Pool Page 6 ASR for Apr ’15 – Mar ‘15 Figure 1 Pt. McIntyre Well Location Map Unit Boundary Point McIntyre Oil Pool Page 7 ASR for Apr ’15 – Mar ‘15 PM2 Approximate Scale 0 1Miles Prudhoe Bay Existing Pipelines Pipelines for EOR PM1 LG1 L1 CCP CGF L2 L3 L5 NK L4 LPC Figure 2. Drill Site and Pipeline Configuration GC1* * GC1 location not to scale Figure 3 Raven Oil Pool Page 1 ASR for Apr ’15 – Mar ‘16 Prudhoe Bay Unit Raven Oil Pool 2016 Annual Reservoir Surveillance Report This Annual Reservoir Report for the period ending March 31, 2016 is submitted to the Alaska Oil and Gas Conservation Commission for the Raven Oil Pool in accordance with Commission regulations and Conservation Order 570. This report summarizes the period between April 1, 2015 and March 31, 2016. A. Reservoir Management 1. Summary Raven is a small oil and gas field in the Permo -Triassic interval (Ivishak and Sag River) located beneath the Niakuk Field (Kuparuk reservoir). Two oil wells, NK-38A (Ivishak producer) and NK-43 (commingled Kuparuk and Sag River producer), produce from the Raven Oil Pool. NK-65A is the only injector in the Raven Field and it provides injection support for the Ivishak producer, NK-38A. Production from the Raven Field started in March 2001 with the completion of the Sag River in NK-43. The Sag River NK-43 was subsequently isolated with a cast iron bridge plug (CIBP), and the well was perforated in the Kuparuk reservoir and produced until 1/2/06 when the CIBP was removed and the Sag River commingled with the Kuparuk. production from NK-38A began in March 2005 from the Ivishak reservoir. Water injection in NK-65A, providing pressure support in the Ivishak reservoir, started in October 2005. The NK-38A producer exhibits good communication with injector NK-65A. Oil Production from the Raven pool averaged 0.13 mbd for the reporting period. The reservoir management plan is to generally replace the voidage created by hydrocarbon production with water injection and keep reservoir pressure at levels that will optimize oil production. A time of decreased voidage replacement was utilized at the end of the reporting period to optimize production. No conversions of producers and injectors are currently planned. 2. Analysis of Reservoir Pressure Surveys Within the Pool Static pressure surveys have been conducted on the wells in the field. Table 3 shows results of static reservoir pressure surveys conducted on the wells sinc e Raven Oil Pool Page 2 ASR for Apr ’15 – Mar ‘16 March 2005. The most recent static reservoir pressure of 3,386 psi, in NK-38A, was taken in July of 2015. It has been shown that with extensive shut-in periods, pressure will continue to build in NK-38A. It is inferred from this response that baffling exists between the injector and producer. 3. Results of Production Logging, Tracer and Well Surveys No logs were indicated to be obtained in Raven during the reporting period. B. Development 1. Progress of Enhanced Recovery Project Implementation and Reservoir Management Summary W aterflood at Raven began in October 2005, using water from the Initial Participating Area Seawater Treatment facilities. From the beginning of the reporting period until March 31 st, 2015 , seawater was used in NK -65A to prov ide injection support for the Ivishak reservoir at an average rate of 2 .8 mbd . Raven Oil Pool Page 3 ASR for Apr ’15 – Mar ‘16 2. Voidage Balance of Produced and Injected Fluids Tables 1 and 2 detail the production, injection and calculated voidage by month for the reporting period. 3. Special Monitoring NK-43 is a commingled producer which produces from both the Kuparuk and Sag River reservoirs. The AOGCC approved co -mingled production in NK-43 with production allocated to each reservoir via geo -chemical analysis in Conservation Order 329B on December 7, 2006. One oil sample was taken from NK-43 during the reporting period for geochemical analysis to confirm production allocation splits between the Sag River and Kuparuk reservoirs. Production allocation splits from the previous geochemical analysis were used for allocation. This analysis shows that 100% of oil production in NK-43 is from the Kuparuk. 4. Future Development Plans (C.O. 570) Permanent production facilities that Raven utilizes were commissioned in March 1995. There have been 3 development wells drilled into the Raven Oil Pool through the end of the reporting period. Future development plans are discussed in the 2015 Raven Plan of Development filed with the Division of Oil and Gas of the Alaska Department of Natural Resources, which the Commission received on June 30, 2015. The Commission will be copied when the 2016 update of the Raven Plan of Development is filed with the division. Raven Oil Pool Page 4 ASR for Apr ’15 – Mar ‘16 Tables and Figures Table 1 - Raven Monthly Production & Injection Summary Produced Produced Produced Injected Injected Injected Cum Prod Cum Prod Oil Gas Water Gas Water MI Oil Gas mstb mmscf mstb mmscf mstb mmscf mstb mmscf Apr-15 30 5 52 100 0 178 0 3,090 16,640 May-15 31 5 66 101 0 137 0 3,095 16,706 Jun-15 30 5 23 91 0 120 0 3,100 16,729 Jul-15 31 1 6 24 0 73 0 3,101 16,735 Aug-15 31 1 6 22 0 69 0 3,102 16,741 Sep-15 30 0 0 0 0 51 0 3,102 16,741 Oct-15 31 1 7 26 0 88 0 3,103 16,748 Nov-15 30 5 137 102 0 86 0 3,108 16,885 Dec-15 31 9 244 181 0 88 0 3,117 17,129 Jan-16 31 4 42 69 0 88 0 3,121 17,171 Feb-16 29 2 17 29 0 35 0 3,123 17,188 Mar-16 31 8 132 114 0 0 0 3,131 17,321 Apr-11 0 0 0 0 0 0 0 0 0 Year 366 46 732 859 0 1,012 0 0 0 Table 2 - Raven Monthly Voidage Balance Produced Produced Produced Injected Injected Injected Net Res. Oil Gas Water Gas Water MI Voidage mrvb mrvb mrvb mrvb mrvb mrvb mrvb Apr-15 30 8 35 101 0 180 0 -36 May-15 31 8 46 102 0 138 0 18 Jun-15 30 7 14 92 0 121 0 -8 Jul-15 31 2 4 24 0 73 0 -44 Aug-15 31 2 3 22 0 70 0 -43 Sep-15 30 0 0 0 0 52 0 -52 Oct-15 31 2 4 26 0 89 0 -56 Nov-15 30 8 101 103 0 87 0 125 Dec-15 31 14 178 183 0 89 0 287 Jan-16 31 6 29 70 0 88 0 17 Feb-16 29 2 12 29 0 35 0 8 Mar-16 31 12 95 116 0 0 0 222 Apr-11 Year 366 71 521 868 0 1,022 0 438 Note: Negative Net Reservoir Voidage indicates IWR>1 Note: Monthly Production/Injection/Voidage for the Ivishak formation. Raven Oil Pool Page 5 ASR for Apr ’15 – Mar ‘16 Table 3 – Raven Ivishak Pressure Survey Data Since March 2005 Sw Name Test Date Pres Surv Type Datum Ss Pres Datum NK-38A 3/29/2005 SBHP 9850 4973 NK-38A 8/1/2005 SBHP 9850 4237 NK-38A 8/7/2005 SBHP 9850 4273 NK-65A 8/9/2005 SBHP 9850 4463 NK-65A 8/15/2005 SBHP 9850 4295 NK-38A 12/24/2005 SBHP 9850 4210 NK-65A 5/24/2006 SBHP 9850 4414 NK-38A 7/26/2006 SBHP 9850 4155 NK-65A 7/26/2006 SBHP 9850 4400 NK-38A 1/23/2007 SBHP 9850 4104 NK-38A 7/6/2007 SBHP 9850 3758 NK-65A 8/16/2007 SBHP 9850 4827 NK-38A 8/24/2007 SBHP 9850 4370 NK-38A 10/30/2007 SBHP 9850 4379 NK-38A 6/9/2008 SBHP 9850 3543 NK-65A 8/17/2008 SBHP 9850 4379 NK-38A 9/2/2008 SBHP 9850 3507 NK-38A 4/29/2009 SBHP 9850 3537 NK-38A 5/18/2009 SBHP 9850 3928 NK-65A 8/8/2009 SFO 9850 4525 NK-38A 8/31/2009 SBHP 9850 4165 NK-65A 6/5/2010 SFO 9850 4534 NK-38A 7/6/2010 SBHP 9850 4090 NK-65A 6/4/2011 SBHP 9850 4468 NK-38A 6/6/2011 SBHP 9850 4402 NK-65A 6/27/2012 SFO 9850 4497 NK-38A 7/14/2012 SBHP 9850 3976 NK-65A 7/13/2013 SFO 9850 4429 NK-38A 12/26/2013 SBHP 9850 3549 NK-38A 6/26/2014 SBHP 9850 3564 NK-65A 7/13/2014 SFO 9850 4674 NK-43 3/12/2015 SBHP 9850 4057 NK-38A 7/31/2015 SBHP 9850 3386