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Home My WebLink About2019 Oooguruk-Kuparuk Oil PoolAnnual Reservoir Surveillance Report Oooguruk-Kuparuk Oil Pool (OKOP) Oooguruk Field May 15th, 2020 Eni Petroleum - Alaska Development Table of Contents SUBJECT PAGE 1.0 Progress of the Enhanced Recovery Project................................................................ 1 2.0 Results and Analysis of Reservoir Pressure Surveys within the Pool ....................... 2 3.0 Results and Analysis of Production and Injection Log Surveys, Tracer Surveys, Observation Well Surveys and Any Other Special Monitoring................................... 2 4.0 Review of Pool Production Allocation Factors and Issues Over the Year.................. 2 5.0 Reservoir Management Summary ................................................................................. 3 ATTACHMENTS ATTACHMENT A: OKOP Well Location Map........................................................................ 5 ATTACHMENT B: 2019 OKOP Voidage Balance by Month.................................................. 6 ATTACHMENT C: OKOP Pressure Report, Form 10-412...................................................... 7 ATTACHMENT D: OKOP Reservoir Pressure Map – December, 2019.................................. 8 ATTACHMENT E: OKOP Annual Reservoir Properties Report, Form 10-428........................ 9 Eni Petroleum - Alaska Development Page 1 1.0 Progress of the Enhanced Recovery Project Eni US Operating Co. Inc. (Eni) acquired 100% working interest ownership of the producing assets within the Oooguruk Unit (OU) on January 31, 2019; the voluntary OU contraction was approved effective June 1, 2019 and Eni was designated the operator effective August 1st, 2019 following resignation of Caelus Natural Resources Alaska, LLC (Caelus) as operator. The OU was contracted to exclude southern leases. None of the contracted area was producing oil or gas. The locations of the existing Oooguruk Kuparuk Oil Pool (OKOP) wells, the current OU, and Oooguruk Kuparuk Participating Area (OKPA) are shown in Attachment A. The OKOP development includes eight wells: ODSK-13i, ODSK-14, ODSN-29 Kuparuk, ODSK-33, ODSK-35Ai, ODSK-38i, ODSN-40i Kuparuk, and ODSK-41. Currently two producers, ODSK-14 and ODSN-29 Kuparuk, and two injectors, ODSK-35Ai and ODSK- 38i, are active. The ODSK-33 well is inactive due to high water cut, the ODSK-13i well remains shut-in for long term pressure fall-off monitoring, the ODSK-41 well is shut-in due to a failed ESP (failed October 17, 2018), and the ODSN-40i Kuparuk is currently shut-in due to limited injection capacity. ODSK-14 production has been limited since the ESP failed in February, 2017 due to a non-competitive total gas oil ratio on gas lift. No rig workovers nor new drilling were conducted in the OKOP in 2019. However, Eni initiated rig repairs, maintenance and material purchases in preparation for future OU workover and drilling programs. Currently all OKOP production wells rely on gas lift for artificial lift. ODSN-29 Kuparuk accounted the majority of OKOP production in 2019.While the ODSN- 29 Kuparuk production has temporarily shut-in Nuiqsut production from the ODSN-29 wellbore, the long-term plan, which requires AOGCC approval, is to commingle production from the two pools at this OU location or alternate production from each zone as the Kuparuk is much more prolific and is at a higher pressure than the underlying Nuiqsut in the area. Annual average daily OKOP production for 2019 was 896 BOPD. Total oil production during 2019 was 326,900 barrels for a total 9,685,661 barrels since field start-up. The 2019 annual average producing gas oil ratio and watercut were 2,878 SCF/STBO and 49%, respectively. When available* seawater injection continued in ODSK-35A and ODSK-38. OKOP water injection was limited to 170 days. Average daily water injection for 2019 was 515 BWPD. Total water injection in 2019 was 188,118 barrels and 15,376,549 barrels since the start of injection in 2009. (*Refer to Section 5 for additional information regarding seawater availability) Eni Petroleum - Alaska Development Page 2 2.0 Results and Analysis of Reservoir Pressure Surveys within the Pool Ten pressure surveys were reported from eight OKOP wells; the pressure survey results are presented in the OKOP Pressure Report, Form 10-412 (See Attachment C). Overall, the pressures in the Kalubik fault block continue to indicate pressure stabilization due to historical voidage replacement, excluding the ODSK-41 area, which, despite being shut-in since October, 2018 due to a failed ESP, continues to show limited communication to offset wells. Pressures from the ODSK-13i injection and fall off test show the western Ivik block has relatively low transmissibility and is not in hydraulic communication with the main Kalubik block development area. Kuparuk pressures measured in the ODSN-29 Kuparuk eastern Ivik well confirmed communication with the main Kalubik fault block but not to ODSK-13i in the western Ivik fault block. The OKOP Reservoir Pressure Map, Attachment D, depicts the OKOP average pressures for December, 2019 including shut-in and producing wells. As of December, 2019 the average OKOP pressure at 6,050 ft TVDss is estimated at 2,600 psi. The average annual producing GOR is 2,878 SCF/STBO (refer to Attachment E, Kuparuk Annual Reservoir Properties Report Form 10-428). 3.0 Results and Analysis of Production and Injection Log Surveys, Tracer Surveys, Observation Well Surveys and Any Other Special Monitoring A chemical tracer program was initiated in May 2012 and completed in 2014. Tracers were injected into ODSK-35Ai and ODSK-38i. Within 20 months of initial injection tracer concentrations were observed in ODSK-33 and ODSK-14 from ODSK-35Ai. To date, ODSK-38i tracer has only been seen in minor amounts in ODSK-33. Produced water samples for ODSN-29 Kuparuk have not shown signs of either tracer. No additional studies or tracer monitoring has been conducted recently. 4.0 Review of Pool Production Allocation Factors and Issues Over the Year Production from the Oooguruk-Torok Oil Pool (OTOP), Oooguruk-Kuparuk Oil Pool (OKOP) and Oooguruk-Nuiqsut Oil Pool (ONOP) is commingled at the surface into a common production line. Allocation between the pools is based on the ratio of total production for a pool to the total production for the Oooguruk Unit. The pool allocation factors for 2019 are: ONOP: 86.4% OKOP: 10.8% OTOP: 2.8% Eni Petroleum - Alaska Development Page 3 Theoretical production for individual wells for all pools is calculated on a daily basis. During 2019 wells were produced with chokes at 100% most of the time due to the capacity of the production line. Daily theoretical production for a well was calculated using the data from the most current well test and the amount of time a well was on production for a given day: oductionlDailyTheoreticaBOPDxDailyRate dayMinutes Minutes Welltest produced Pr)( 1440  The daily allocation factor for the unit is calculated by dividing the actual total production for the day by the sum of the theoretical daily production for each individual well. Daily allocated production is assigned to each well by multiplying its theoretical daily production by the daily allocation factor. The average daily allocation factor for 2019 was 1.0261. 5.0 Reservoir Management Summary The Alaska Oil and Gas Conservation Commission (AOGCC) issued pool rules under Conservation Orders No. 645, 596 and 597 for the OTOP, OKOP and ONOP, respectively. While there is no subsurface commingling, unitized substances produced from the three oil pools are commingled on the surface. Area Injection Order No. 33 authorizing the injection of fluids for enhanced oil recovery in the OKOP was issued by the AOGCC in 2008 and injection commenced in 2009. A simulation model has been maintained and updated to assist in reservoir and flood management decisions in the OKOP OKOP 2019 production was primarily associated with the ODSN-29 Kuparuk in the eastern Ivik fault block. Performance to-date suggests a significant associated pore volume with support from the Kalubik fault block injection wells, ODSK-35A and ODSK- 38, but not with the ODSK-13 well in the western Ivik fault block (refer to Attachments C and D). Since initiating Kuparuk production from ODSN-29 there has been no change in the fall-off trend in the ODSK-13 well. Future development plans of the expanded area are contingent on the longer term performance from the well and evaluation of alternatives to further develop this area of the OKOP. Because the main Kalubik fault block development area is a mature flood, in a dual porosity system, with highly variable matrix permeability and open fracture networks, voidage replacement has been purposely reduced, currently at 63% cumulative voidage replacement, to minimize waterflood by-pass while stabilizing the reservoir pressure and GOR, refer to Attachment B. As a result, the producing OKOP water oil ratio increases have slowed and oil production has remained relatively stable. Continued flood throughput and reliable water supply are critical to long-term OKOP recovery. Effective Eni Petroleum - Alaska Development Page 4 July 2019, KRU converted the 3-HAMI water injection line from seawater to produced water. This removed the OU seawater supply access point at DS-3A. No seawater was injected at ODS from July 4, 2019 through December 31, 2019. Consequently, Eni moved forward with a seawater injection supply (SWIS) enhancement project. The SWIS project will bypass KRU CPF-3 and consistently supply ODS with up to 25,000 bpd of seawater, increase water injection reliability, and avoid produced water injection at ODS. SWIS pipeline and pump module components were installed in 2019, and start up is planned in May, 2020. In association with the SWIS project, water injection supply pressures will be boosted from 2,800 psi to 3,700 psi. High-pressure injection testing to 3,300 psi in 2018 on four Oooguruk Nuiqsut injection wells, ODSN-26i, ODSN-27i, ODSN-32i and ODSN- 34i, demonstrated an average four-fold increase in injectivity with no containment or well integrityconcerns, which is consistent with historical performance and modeling. Typically higher pressures are not needed for Kuparuk reservoir injection; however, one well ODSN-40 with limited injectivity, may benefit. The AOGCC has confirmed increasing the pressure limit to 3,700 psi from 2,800 psi for both the Nuiqsut and Kuparuk pools is consistent with the Pool Area Injection Orders in that the increased pressure will not fracture the confining zones or migrate injected fluids out of the approved injection stratum. Eni Petroleum - Alaska Development Page 5 ATTACHMENT A. OKOP Well Location Map Eni Petroleum - Alaska Development Page 6 ATTACHMENT B 2019 OKOP Voidage Balance by Month Month Oil, MRB Free Gas, MRB Water, MRB Total Voidage, MRB Year Cum, MRB Cum since start-up, MRB Gas, MRB Water. MRB Total Injection, MRB Year Cum, MRB Cum. since start-up, MRB Net Injection, MRB Year Cum, MRB Cum since start-up, MRB CumSince Start-Upthru 2018 >> 22,577 CumSince Start-Upthru 2018 >> 15,188 -7,389 Jan-19 36 52 28 116 116 22,693 0 42 42 42 15,230 -74 -74 -7,463 Feb-19 35 89 29 153 269 22,846 0 40 40 82 15,270 -113 -187 -7,576 Mar-19 39 95 27 161 430 23,007 0 26 26 108 15,296 -135 -322 -7,711 Apr-19 35 79 25 139 569 23,146 0 31 31 139 15,327 -108 -430 -7,819 May-19 37 94 25 156 725 23,302 0 25 25 164 15,352 -131 -561 -7,950 Jun-19 31 104 28 163 888 23,465 0 22 22 186 15,375 -140 -701 -8,090 Jul-19 32 99 29 160 1,048 23,625 0 2 2 188 15,377 -158 -860 -8,248 Aug-19 22 68 19 109 1,157 23,734 0 0 0 188 15,377 -109 -969 -8,358 Sep-19 33 111 27 171 1,328 23,905 0 0 0 188 15,377 -171 -1,140 -8,528 Oct-19 38 109 27 173 1,501 24,078 0 0 0 188 15,377 -173 -1,313 -8,702 Nov-19 35 103 24 162 1,663 24,240 0 0 0 188 15,377 -162 -1,475 -8,864 Dec-19 36 108 27 171 1,834 24,412 0 0 0 188 15,377 -171 -1,646 -9,035 2019 Totals 409 1,110 315 1,834 0 188 188 -1646 Produced Fluids Injected Fluids Net Injection (Injection - Production) Eni Petroleum - Alaska Development Page 7 ATTACHMENT C OKOP Pressure Report, Form 10-412 6. Oil Gravity: 21 - 26 8. Well Name and Number: 9. API Number 50XXXXXXXXXXXX NO DASHES 10. Type See Instructions 11. AOGCC Pool Code 12. Zone 13. Perforated Intervals Top - Bottom TVDSS 14. Final Test Date 15. Shut-In Time, Hours 16. Press. Surv. Type (see instructions for codes) 17. Temp.18. Depth Tool TVDSS 19. Final Observed Pressure at Tool Depth 20. Datum TVDSS (input) 21. Pressure Gradient, psi/ft. 22. Pressure at Datum (cal) ODSK-13 50703206070000 WI 576100 Kuparuk 6117 - 6195 12/15/2019 52,084 PFO 163 6,102 3,754 6,050 0.45 3,731 ODSK-14 50703206100000 O 576100 Kuparuk 6123 - 6163 1/23/2020 8,061 SBHP 168 6,014 2,817 6,050 0.40 2,831 ODSK-14 50703206100000 O 576100 Kuparuk 6123 - 6163 12/15/2019 7,111 PBU 72 -13.5 1,507 6,050 0.22 2,870 ODSN-29 50703206610000 O 576100 Kuparuk 6083 - 6121 8/18/2019 236 PBU 159 5,936 2,350 6,050 0.44 2,400 ODSK-33 50703205620000 O 576100 Kuparuk 5990 - 6043 12/15/2019 51,412 PBU 65 -13.5 466 6,050 0.35 2,588 ODSK-35A 50703205600100 WI 576100 Kuparuk 6085 - 6126 12/15/2019 5,988 PFO 53 -13.5 687 6,050 0.40 3,112 ODSK-38 50703205840000 WI 576100 Kuparuk 6013 - 6041 12/15/19 4,080 PFO 145 5,839 2,503 6,050 0.44 2,597 ODSN-40 50703205710000 WI 576100 Kuparuk 5926 - 5940 4/7/18 54,629 PFO 63 -13.5 20 6,050 0.40 2,445 ODSK-41 50703205850000 O 576100 Kuparuk 5980 - 6034 1/18/20 10,984 SBHP 151 5,664 1,549 6,050 0.36 1,688 ODSK-41 50703205850000 O 576100 Kuparuk 5980 - 6034 12/15/19 10,152 PBU 55 -13.5 917 6,050 0.12 1,668 23. All tests reported herein were made in accordance with the applicable rules, regulations and instructions of the Alaska Oil and Gas Conservation Commission. I hereby certify that the foregoing is true and correct to the best of my knowledge. Oooguruk Oooguruk-Kuparuk 6050 0.7 3. Unit or Lease Name: 4. Field and Pool: 5. Datum Reference: Production Engineer May 1, 2020 Eni US Operating Company Inc. (Eni US) 3700 Centerpoint Drive, Suite 500, Anchorage, AK 99503 7. Gas Gravity: Keith Lopez Signature Printed Name Title Date Eni Petroleum - Alaska Development Page 8 ATTACHMENT D OKOP Reservoir Pressure Map – December, 2019 Eni Petroleum - Alaska Development Page 9 ATTACHMENT E OKOP Annual Reservoir Properties Report, Form 10-428 3. Field and Pool Code: 4. Pool Name 5. Reference Datum (ft TVDSS) 6. Temperature (°F) 7. Porosity (%) 8. Permeability (md) 9. Swi (%) 10. Oil Viscosity @ Original Pressure (cp) 11. Oil Viscosity @ Saturation Pressure (cp) 12. Original Pressure (psi) 13. Bubble Point or Dew Point Pressure (psi) 14. Current Reservoir Pressure (psi) 15. Oil Gravity (°API) 16. Gas Specific Gravity (Air = 1.0) 17. Gross Pay (ft) 18. Net Pay (ft) 19. Original Formation Volume Factor (RB/STB) 20. Bubble Point Formation Volume Factor (RB/STB) 21. Gas Compressibility Factor (Z) 22. Original GOR (SCF/STB) 23. Current GOR (SCF/STB) 576100 Kuparuk 6050 160 13 - 32 50 - 100 30 2 - 4 2 - 4 3150 2600 2600 21 - 26 0.7 3 - 50 1 - 40 1.26 1.24 0.7 450 2878 5/1/2020 STATE OF ALASKA ALASKA OIL AND GAS CONSERVATION COMMISSION ANNUAL RESERVOIR PROPERTIES REPORT 1. Operator: 2. Address: Eni US Operating Company Inc. (Eni US) 3700 Centerpoint Drive, Suite 500, Anchorage AK 99503 Printed Name Keith Lopez Date Production Engineer I hereby certify that the foregoing is true and correct to the best of my knowledge. Signature Title