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Home My WebLink About2011 Oooguruk UnitPIONEER NATURAL RESOURCES ALASKA April 2, 2012 Commissioner Cathy Foerster Alaska Oil and Gas Conservation Commission 333 W. 7th Ave., Suite 100 Anchorage, AK 99501 Dale Hoffman, CPL Senior Staff Landman Pioneer Natural Resources Alaska, Inc. 700 G Street, Suite 600 Anchorage, AK 99501 (907) 343-2108 • Fax (907) 343-2193 dale.hoffman@pxd.com APR 0 2 2012 Alaska Oil & Gas Cana. Canmissicn Annual Reservoir Surveillance Reports — Oooguruk Unit Ooocturuk-Kuparuk, Oooguruk-Nuigsut & Oooguruk-Torok Oil Pools Dear Commissioner Foerster: The Alaska Oil and Gas Conservation Commission (AOGCC) approved pool rules for the Oooguruk-Kuparuk, Oooguruk-Nuiqsut and Oooguruk-Torok pools within the Oooguruk Unit as Conservation Orders 596, 597 and 645, respectively. Rule 9 of the orders requires the filing of annual surveillance reports, which are attached hereto. Please let us know if you have any questions or require additional information regarding these reports. Sincerely, f Attachments PIONEER RECEIVED APR 0 2 Z02 Alaska Oil & Gas Cana. Commission Aqcharsge Annual Reservoir Surveillance Report Oooguruk-Kuparuk Oil Pool Oooguruk Field April 1, 2012 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 .....................1 3.0 Results and Analysis of Production and Injection Log Surveys, Tracer Surveys, Observation Well Surveys and Any Other Special Monitoring..................................1 4.0 Review of Pool Production Allocation Factors and Issues Over the Year................2 5.0 Reservoir Management Summary................................................................................ 2 Attachments A. Voidage Balance by Month of Produced Fluid and Injected Fluids 2011 B. Map of Kuparuk Well Locations C. Form 10-412 Pressure Report for Kuparuk D. Kuparuk Reservoir Pressure Map — July 2011 Annual Reservoir Surveillance Report Pioneer Natural Resources Alaska, Inc. Oooguruk-Kuparuk Oil Pool Oooguruk Development Project 1.0 Progress of the Enhanced Recovery Project During 2011, activities within the Kuparuk Pool were extended to two additional fault blocks. One well (ODSK-13) was drilled in the Oooguruk-Kuparuk Oil Pool within the Ivik Fault Block, and is currently shut-in pending stimulation treatment. One well (ODSN-40) had rig workover operation, converting the well to injection within the Colville Delta fault block. The ODSK-14, ODSK-33 and ODSK-41 wells continued to produce throughout 2011. Water breakthrough occurred in ODSK-35i prior to conversion to injection. The ODSK-38i well continued on injection throughout the year and ODSK-35i was converted to injection late in the year, after period of pre -production. Both injectors are performing as expected in replacing off take, as of December 2011. Injection well ODSK-42i was active for part of the year. The ODSK-42i well could not maintain consistent injection at the water injection header pressure post gel treatment in 2010. The locations of these wells are shown on Attachment B. Average daily Kuparuk production for 2011 was 3,578 BOPD. Cumulative oil production from the Oooguruk-Kuparuk Oil Pool during 2011 was 1,306 MBO and 6,919 MBO since field start- up. No additional drilling for the pool is planned for 2012. Average daily Kuparuk water injection for 2011 was 6,149 BWPD. Cumulative water injection in the Oooguruk-Kuparuk Oil Pool during 2011 was 2,244 MBW and 7,966 MBW since the start of the project. 2.0 Results and Analysis of Reservoir Pressure Surveys within the Pool Pressure build up tests were completed in ODSK-33, ODSK-35 and ODSK-41 during 2011, the results of which are presented in Attachment C. In addition, pressure fall off tests were performed on ODSK-38i and ODSK-42i during the year. The pressure build up in ODSK-33, ODSK-41, AND ODSK-35 indicate reservoir pressure was being drawn down around the wellbores compared to original static pressure. Water injection support is evident in the ODSK-33 pressure and production results. ODSK-41 is still not seeing much support from injection in ODSK-38i. The pressure fall off in ODSK-38i indicates elevated pressures around this wellbore due to extensive water injection. The pressure in ODSK-42i indicates pressure drawdown in this area of the reservoir as the well has been shut in from injection since the gel squeeze to shut off thief zones. 3.0 Results and Analysis of Production and Injection Log Surveys, Tracer Surveys, Observation Well Surveys and any Other Special Monitoring No special logging or monitoring program was initiated. Page 1 of 7 4.0 Review of Pool Production Allocation Factors and Issues Over the Year Production from the Oooguruk-Kuparuk and Oooguruk-Nuigsut pools is commingled at the surface into a common production line. Allocation between the pools is based on ratio of total production for a pool to the total production for the Oooguruk Unit. The pool allocation factors for 2011 are: Oooguruk-Kuparuk Pool: 50.3% Oooguruk-Torok Pool: 6.6% Oooguruk-Nuigsut Pool: 43.1% Theoretical production for individual wells for both pools is calculated on a daily basis. During 2011 wells were produced with chokes at 100% the 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: MinutesproducedxDailyRate(BOPD) wellte, = TheoreticalDaily Production 1440 Minutes day 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 2011 was 0.92. 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 Oooguruk-Torok, Oooguruk-Kuparuk and Oooguruk-Nuigsut reservoirs, respectively. Subsurface development of the Oooguruk Unit is done with dedicated development wells to the Oooguruk-Torok, Oooguruk-Nuiqsut and Oooguruk-Kuparuk oil pools with no subsurface commingling. Unitized substances produced from the Oooguruk-Torok , Oooguruk-Nuiqsut and the Oooguruk-Kuparuk oil pools are commingled on the surface. Area injection orders authorizing the injection of fluids for enhanced oil recovery in the Oooguruk-Kuparuk and Oooguruk-Nuiqsut reservoirs were issued by the AOGCC as Area Injection Orders No. 33 and 34, respectively. Pioneer commenced injection into both reservoirs in 2009. As of January 2012, there are four active producing and three active injecting Kuparuk wells. Kuparuk production has exceeded expectations from ODSK-33, ODSK-41 and ODSK-14 due to possible non -matrix flow into these wells. Kuparuk injection commenced in 2009, into ODSK- 38i with excellent injection rates. Kuparuk injection commenced in 2011 into ODSK-35i and ODSN-40 (converted from Nuiqsut completion to Kuparuk completion). Injection rate into ODSK-35i is very good, with rate into ODSN-40 good, considering the pay thickness at that location. Page 2 of 7 The better than expected water injection rate has arrested the gas/oil ratio (GOR) increase in the ODSK-33 and has stabilized the flowing bottom hole pressure. The ODSK-33 experienced water breakthrough in August 2010. This was approximately the timing that reservoir simulation had suggested for breakthrough. The water cut increased relatively rapidly and reached approximately 82% by the end of, 2011. ODSK-41 is much further away from injection and has not yet seen a dramatic response to water injection in ODSK-38i. Injection logging confirmed that water injection in the K-38i well was limited to the perforated Kuparuk section. Injection was initiated in ODSK-42Ai in January 2010. Unfortunately, this resulted in a very early water breakthrough event in the ODSK-41 well. The ODSK-42Ai was shut in and the water injection rate quickly decreased from the producing well. It is possible a fracture system connects the two wells together. This was not unexpected based on the high productivity from the ODSK-41 wells originally. In 2010, ODSK-42i was squeezed with a combination of gels to attempt to seal up the fracture connection. Those are polyacrylamide gels that set up to a "ringing gel" at reservoir conditions. The ODSK-42Ai was placed back on injection and was injecting just under 1,000 BWPD for about 30 days. Then, after an upset event from the Kuparuk River Unit Seawater Treatment Plant, continuous injection could not be sustained. Some solid materials may have caused some near wellbore plugging. ODSK-35 and ODSK-14 were both drilled during 2010. The total thickness of the Kuparuk was less than expected in these wells to the north and northwest of the ODSK-33. The wells had very high initial productivity from good reservoir quality, but have declined due to the thinner nature of the reservoir. ODSK-35i was converted to injection in late, 2011. With ODSK-35i and ODSK-38i both injecting, reservoir voidage replacement is maintained, pressure in the reservoir is increasing, and GORs are decreasing. ODSK-13 was drilled in late 2011 as horizontal producer completed to test the thickness and productivity of the Ivik fault block. Unfortunately, the well currently is awaiting stimulation treatment prior to production. ODSN-40, a Nuiqsut horizontal completion, had rig workover in 2011 to convert to dedicated Kuparuk injection. This well was completed and is injecting into the Kuparuk formation within the Colville-Delta fault block in an attempt to aid with pressure support and oil recovery into the ODSK-33 producer within the Kalubik fault block. Page 3 of 7 ATTACHMENT A Voidage Balance by Month of Produced Fluids and Injected Fluids 2011 Produced Fluids Month Oil, MRP Free Gas, MRB Water, MRB Total Voidage, MRB Year Cum, MRB Cum since start-up, MRB Cum Since Start -Up Cum, Total Year since Gas, 23253 Jan -11 141 34 76 251 251 23504 Feb -11 147 31 85 263 515 24019 Mar -11 141 32 64 237 752 24770 Apr -11 183 66 129 377 1129 25900 May -11 184 86 106 376 1505 27405 Jun -11 156 86 113 355 1861 29265 Jul -11 143 88 136 367 2227 31493 Aug -11 112 68 128 308 2535 34028 Sep -11 122 51 147 320 2855 36883 Oct -11 115 49 161 325 3181 40064 Nov -11 96 44 159 299 3480 43543 Dec -11 93 28 167 288 3767 47311 2011 Totals 1633 664 1471 3767 0 2267 Injected Fluids Page 4 of 7 Net Injection (Injection - Production) Cum Net Cum. Formation Import Cum, Total Year since Gas, Gas, Water. Injection, Cum, start-up, MRB MRB MRB MRB MRB MRB -1318 -316 -681 -1634 -245 2546 0 -95 0 193 193 193 2739 0 -66 0 52 52 245 2791 0 -48 0 142 142 387 2933 0 33 0 61 61 448 2994 0 0 131 131 579 3125 0 0 261 261 840 3386 0 0 70 70 910 3456 0 0 242 242 1151 3697 0 0 225 225 1376 3922 0 0 277 277 1654 4200 0 0 293 293 1946 4492 0 0 321 321 2267 4813 0 0 2267 2267 Page 4 of 7 Net Injection (Injection - Production) Cum Net Year since Injection, Cum, start-up, MRB MRB MRB -953 -58 -58 -1011 -211 -270 -1223 -95 -365 -1318 -316 -681 -1634 -245 -926 -1879 -95 -1021 -1974 -297 -1318 -2271 -66 -1384 -2337 -95 -1479 -2432 -48 -1527 -2480 -7 -1533 -2486 33 -1501 -2454 -1501 ATTACHMENT B Map of Kuparuk Well Locations Page 5 of 7 ADL389956 \ADL389955 R5 Of ;r- ADL379301 ADL387 ADL389959 ADL38 58`�,, L-4-1 ODS•K-13 54 ADO8953 ADL3899 � obSk,-35 OD D ADL3899 ADL349949 ADL355037 A D 6 N K- OD ADL38\995� ADD 51 VN Legend ADL355039 Kuparuk PA ADO 038 N Unit Boundary W Lease Boundary Township Boundary 7 Miles 0 .5 1 2 Page 5 of 7 ATTACHMENT C Form 10-412 Pressure Report for Kuparuk Page 6 of 7 STATE OF ALASKA ALASKA OIL AND GAS CONSERVATION COMMISSION RESERVOIR PRESSURE REPORT 1. Operator: Roneef Natural Resources Alaska 2. Address: 700 G Street, Suite 600, Anchorage, AK 99501 3. Und or Lease Name: Oooguruk 4. Fell and Pool. 5. Datum Reference: Oooguruk-Kuparuk 6050 6. Oil Gravity 25 7. Gas Gravity 0.7 8. Well Name and 9. AR Number Number: 50XXXXXXXXXXXX NO DASHES 10. Type See Instructions 11. AOGCC Pool Code 12. Zone 13. Perforated 14. Final Test 15. Shut -In 16, Press, 17. B.H. 18. Depth Intervals Date Time, Hours Surv. Type Terry. Tool TVDSS Top - Bottom (see lVDSS instructions for codes) 19. Final Observed Pressure at Tool Depth 20. Datum TVDSS (input) 21. Pressure Gradient, psi/ft. 22. Pressure at Datum (cal) ODSK-33 50703205620000 O 576100 Kuparuk 5990-6043 8/23/11 135 PBU 166 5946 2085 6050 0.39 2,126 ODSK-35 50703205600100 O 576100 Kuparuk 6039-6057 8/23/11 135 PBU 1 158 5793 1460 6050 0.39 1,560 ODSK-41 50703205850000 O 576100 Kuparuk 5980-6034 8/23/11 1135 PBU 157 5653 921 6050 0.39 1,076 ODSK-38 50703205840000 WI 576100 Kuparuk 5950-5981 9/4/11 95 PFO 118 5840 3413 6050 0.44 3,505 ODSK-42 50703206050100 WI 576100 Kuparuk 5954-5970 9/6/11 131 PFO 141 5625 2809 6050 0.39 2,975 'Recorded reservoir pressure prior to flow ing back w ell 23. All tests reported herein were made in accordance w th the applicable rules, regulations and instructions of the Alaska Oil and Gas Conservation Comaissio n. I hereby certify that the foregoing is true and correct to the best of my know ledge. Signature Title Printed Name Date Page 6 of 7 ATTACHMENT D Kuparuk Reservoir Pressure Map — August 2011 ATTACHMENT D Kuparuk Reservoir Pressure Map —August 2011 40CCOW E, 7 J_ Pioneer Natural Resources Alaska 1:6336�'N August 2011 Kuparuk Reservoir Pressure KILOMETRES VALES, NAD274AIaSka zone 4(EI'SG 24734) Transvtme Wnmtor etarke Ise Sphomw Natural 0091W (l= Ocrw. 54 00 DON) At ARKA ATATF Pt ANP 76NF d Page 7 of 7 PIONEER w' APR 022012 Alaska 411 & Gag Cons. CO"T issiOn Anc c r a g e Annual Reservoir Surveillance Report Oooguruk-Nuigsut Oil Pool Oooguruk Field April 1, 2012 Table of Contents S PAGE 1.0 Progress of the Enhanced Recovery Project.............................................................. 1 2.0 Results and Analysis of Reservoir Pressure Surveys within the Pool......................1 3.0 Results and Analysis of Production and Injection Log Surveys, Tracer Surveys, Observation Well Surveys and any Other Special Monitoring ........ 1 4.0 Review of Pool Production Allocation Factors and Issues over the Year ................. 2 5.0 Reservoir Management Summary................................................................................2 Attachments A. Voidage Balance by Month of Produced Fluid and Injected Fluids 2011 B. Map of Nuiqsut Well Locations C. Form 10-412 Pressure Report for Nuiqsut D. Nuiqsut Reservoir Pressure Maps — July 2011 Annual Reservoir Surveillance Report Pioneer Natural Resources Alaska, Inc. Oooguruk-Nuiqsut Oil Pool Oooguruk Development Project 1.0 Progress of the Enhanced Recovery Project During 2011, two injection wells (ODSN-23i, ODSN-26i) were drilled and pre -produced. One injection well (ODSN-15i) was converted to water injection before year end after a period of pre -production, beginning the first water -flood pattern within the Colville - Delta fault block. ODSN-31, ODSN-37 and ODSN-36 continued to produce throughout 2011. They are supported by water and gas injection in ODSN-32i and ODSN-34i. As part of planned under -saturated water -alternating -gas (USWAG) process, gas injection has continued in ODSN-32i throughout most of the year. At year end, gas injection has also been initiated into ODSN-15i. The locations of all Nuiqsut wells are shown on Attachment B. Average daily Nuiqsut production during 2011 was 3,061 BOPD. Cumulative oil production from the Oooguruk-Nuiqsut Oil Pool during 2011 was 1,117 MBO and is 2,580 MBO since field start-up. During 2011, water and gas injection continued in the Oooguruk-Nuiqsut oil pool. Offset producing wells within the Kalubik Fault Block (ODSN-31, ODSN-36 and ODSN- 37) have seen gas/ oil ration (GOR) stabilization and arrest of production decline. Average daily Nuiqsut injection during 2011 was 2,279 BWPD and 2,113 Mscfd. Cumulative water injection in the Oooguruk-Nuiqsut Oil Pool during 2011 was 832 MBW and 1,595 MBW since the start of the project. Cumulative gas injection in the Oooguruk-Nuiqsut Oil Pool during 2011 was 771 MMscf and 1,101 MMscf since the start of the project. 2.0 Results and Analysis of Reservoir Pressure Surveys Within the Pool An initial static pressure test was completed on the three new Nuiqsut wells. Additionally, various pressure build-up or static tests were completed on the Nuiqsut wells in 2011. These pressures are reported in the attached 10-412 pressure form. The pressure build up tests indicate that pressure is being drawn down around the production well locations and is high around the injection wells. Waterflood injection began in 2009 in the ODSN-32i and ODSN-34i. GOR reduction and production decline stabilization have been observed in the offset producing wells within the Kalubik fault block. The pressure surveys confirm that the Nuiqsut reservoir is low permeability evidenced by the high pressures at the injectors and low pressures at the producers. 3.0 Results and Analysis of Production and Injection Log Surveys, Tracer Surveys, Observation Well Surveys and any Other Special Monitoring In three Nuiqsut wells surveillance equipment was placed in the production liner to assess oil and water production conformance along the lateral via target fluid tracers which were monitored and analyzed by collecting surface fluid samples over time. Page 1 of 7 Annual Reservoir Surveillance Report Pioneer Natural Resources Alaska, Inc. Oooguruk-Nuigsut Oil Pool Oooguruk Development Project Initial data indicate adequate tracer concentrations are being returned in the produced fluids. A quantitative analysis is in progress. 4.0 Review of Pool Production Allocation Factors and Issues Over the Year Production from the Oooguruk-Kuparuk and Oooguruk-Nuigsut pools is commingled at the surface into a common production line. Allocation between the pools is based on ratio of total production for a pool to the total production for the Oooguruk Unit. The pool allocation factors for 2011 are: Oooguruk-Kuparuk Pool: 50.3% Oooguruk-Torok Pool: 6.6% Oooguruk-Nuigsut Pool: 43.1% Theoretical production for individual wells for both pools is calculated on a daily basis. During 2011 wells were produced with chokes at 100% the vast majority 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: Minutes produced 1440Minutes xDailyRate(BOPD)�,=TheoreticalDailyProduction day 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 2011 was 0.92. 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 Oooguruk-Torok, Oooguruk-Kuparuk and Oooguruk-Nuigsut reservoirs, respectively. Subsurface development of the Oooguruk Unit is done with dedicated development wells to the Oooguruk-Torok, Oooguruk-Nuigsut and Oooguruk-Kuparuk oil pools with no subsurface commingling. Unitized substances produced from the three oil pools are commingled on the surface. Area injection orders authorizing the injection of fluids for enhanced oil recovery in the Oooguruk-Kuparuk and Oooguruk-Nuigsut reservoirs were issued by the AOGCC as Area Injection Orders No. 33 and 34, respectively. Pioneer commenced injection into both reservoirs in 2009. As of January 2012 there are six producing wells and five injection wells, two of which are currently pre -producing in the Oooguruk-Nuigsut oil pool. Currently, eight of those wells are active production wells and three are active injection wells. Page 2 of 7 Annual Reservoir Surveillance Report Oooguruk-Nuiqsut Oil Pool Pioneer Natural Resources Alaska, Inc. Oooguruk Development Project The ODSN-15i was converted to injection in 2011. During 2011, ODSN-40 had a rig workover that installed injection liner equipment for dedicated Kuparuk injection. Water injection supply has been variable from the Kuparuk River Unit supply system. This has hampered efforts to maximize water injection during 2011. The focus for 2012 will be to maximize water and gas injection and to monitor for pressure and rate response in the offset production wells. ODSN-32i and ODSN-34i both had high pressure breakdown stimulation treatments for enhanced injection rate. Page 3 of 7 ATTACHMENT A V oidage Balance by Month of 1 Produced Fluids Pr 1 Tl • 1 - -� UUUICU 1"1UlUa Q1tU 1IUV%-lCU 1'l Ul UA d.U-L Injected Fluids Year Cum since Total Total Year Cum since Import Gas, Water. Injection, Water, Voidage, Cum, start-up, Month Oil, MRB Free Gas, MRB MRB MRB MRB MRB Cum Since Start -Up -277 1236 0 0 61 1823 Jan -11 109 15 0 124 124 1947 Feb -11 123 15 0 139 263 2086 Mar -11 117 29 1 147 410 2233 Apr -11 106 24 0 130 540 2363 May -11 101 12 2 115 655 2478 Jun -11 98 15 1 114 769 2592 Jul -11 97 17 0 114 884 2706 Aug -11 95 12 0 108 992 2815 Sep -11 113 11 1 126 1117 2940 Oct -11 97 14 1 111 1229 3052 Nov -11 92 12 2 106 1334 3157 Dec -11 126 67 1 194 1528 3351 2011 Totals 1274 244 10 1528 Pr 1 Tl • 1 - -� UUUICU 1"1UlUa Q1tU 1IUV%-lCU 1'l Ul UA d.U-L Injected Fluids Page 4 of 7 Net Injection (Injection - Production) Net Year Cum since Total Year Cum. since Formation Import Gas, Water. Injection, Cum, start-up, Gas, MRB MRB MRB MRB MRB MRB -47 -192 -778 -86 -277 1236 0 0 61 61 61 1297 0 0 58 58 119 1355 0 0 100 100 219 1455 31 0 13 44 263 1499 55 0 15 70 333 1569 80 0 15 95 428 1665 43 0 103 146 575 1811 6 0 127 133 708 1944 67 0 102 169 877 2113 99 0 88 187 1064 2300 69 0 81 150 1213 2449 89 0 78 167 1380 2616 540 0 840 1380 Page 4 of 7 Net Injection (Injection - Production) Net Year Cum since Injection, Cum, start-up, MRB MRB MRB -587 -63 -63 -650 -81 -144 -731 -47 -192 -778 -86 -277 -864 -45 -322 -909 -19 -341 -928 32 -309 -896 25 -284 -870 43 -241 -827 75 -165 -752 44 -121 -708 -27 -148 -735 -148 ATTACHMENT B Map of Nuiqsut Well Locations Page 5 of 7 ADL389956 ADL38995 AE� 9301 ADL389960 ADL38996 OMDDSN-26 ADL38!4158 06�-31 L389954 DL389 3 'o W3 OD N-340IDS ODSN-36 -'ODSN-1 A �38995 389949 ADL389949 DS -2 7 \IN 9 ADL389951 0 -17 Legend ADL355039 Nuiqsut PA N A Unit Boundary WE + ' S Lease Boundary Township Boundary Miles 0 0.5 1 2 4 Page 5 of 7 ATTACHMENT C Form 10-412 Pressure Report for Nuiasut Page 6 of 7 STATE OF ALASKA ALASKA OIL AND GAS CONSERVATION COMMISSION RESERVOIR PRESSURE REPORT 1. Operator: Pioneer Natural Resources Alaska 2. Address: 700 G Street, Suite 600, Anchorage, AK 99501 3. Unit or Lease Name: Oooguruk 4. Field and Pool: Oooguruk-Nuiqsut 5. Datum Reference: 6350 6. Oil Gravity: 20 7. Gas Gravity: 0.7 8. Well Name and Number: 9. AR Number 50� NO DASHES 10. Type See Instructions 11. AOGCC Pool Code 12. Zone 13. Perforated Intervals Top - Bottom TVDSS 14. Final Test 15. Shut -In 16. Aess. Date Time, Hours Surv. Type (see instructions for codes) 17. B.H. Temp. 18. Depth Tool TV DSS 19. Final Observed Pressure at Tool Depth 20. Datum TV DSS (input) 21. Pressure Gradient, psi/ft. 22. Pressure at Datum (cal) ODSN-18 50703206240000 O 576150 Nuiqsut 6207-6232 1/10/11 Initial SBHP 166.9 6,160 3253 6350 0.40 3,329 ODSN-23 50703206390000 O 576150 Nuiqsut 6178-6555 7/25/11 Initial SBHP 147 5,594 2885 6350 0.40 3,187 ODSN-16 50703206200000 O 576150 Nuiqsut 6192-6235 8/23/11 135 PBU 173 6,049 1923 6350 0.40 2,043 ODSN-17 50703206220000 O 576150 Nuiqsut 6122-6305 8/23/2011 1 135 PBU 1 173 6,064 2038 6350 0.40 2,152 ODSN-31 50703205650000 O 576150 Nuiqsut 6074-6263 8/23/2011 135 PBU 164 5,762 1387 6350 0.40 1,622 ODSN-23 50703206390000 O 576150 Nuiqsut 6181-6221 8/25/2011 135 PBU 151 5,577 1 2259 6350 0.40 2,568 ODSN-32 50703205660000 WAG 576150 Nuiqsut 6161-6314 8/28/11 237 PFO 138 5,969 4564 6350 0.44 4,732 ODSN-15 50703206180000 WAG 576150 Nuiqsut 6170-6210 9/6/2011 458 PFO 135 5,416 2899 6350 0.40 3,273 ODSN-40 50703205710000 WAG 576150 Nuiqsut 6100-6337 9/6/11 131 PFO 119 5,857 4451 6350 0.40 3,230 ODSN-26 50703206420000 O 576150 Nuiqsut 6056-6226 11/29/11 Initial SBHP 164 5,922 1 3294 6350 0.40 3,465 23. All tests reported herein were made in accordance w ith the applicable rules, regulations I hereby certify that the foregoing is true and correct to the best of try knowledge. Signature Printed Name and instructions of the Alaska Oil and Gas Conservation Commssion. Title Date Page 6 of 7 ATTACHMENT D Nuiqsut Reservoir Pressure Map — August 2011 ATTACHMENT D Nuiqsut Reservoir Pressure Map— August 2011 4CIIIIIIIIIII � �OCO ,, 111WOOF t 41XM, I KADVIAInka zone 4(EV$G w34) TfaftSvOr" V*MDIOr Name lase Sphomw NAtUMI 00910: (l" 00 OQW. 54 00 OQN) A Page 7 of 7 tvl..UW N f'114,�UfP 1. hMOW �, t�:,�>>,V N Pioneer Natural Resources Alaska 1:63360 August 2011 Nuiqsut Reservoir Pressure KILOMETRES KADVIAInka zone 4(EV$G w34) TfaftSvOr" V*MDIOr Name lase Sphomw NAtUMI 00910: (l" 00 OQW. 54 00 OQN) A Page 7 of 7 tvl..UW N f'114,�UfP 1. hMOW �, PIONEER RECEIVED APR Q 2 2012 Alaska Gii & Gas Cons. ComTnission Anchoraue Annual Reservoir Surveillance Report Oooguruk-Torok Oil Pool Oooguruk Field April 1, 2012 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 .....................1 3.0 Results and Analysis of Production and Injection Log Surveys, Tracer Surveys, Observation Well Surveys and Any Other Special Monitoring..................................1 4.0 Review of Pool Production Allocation Factors and Issues Over the Year................2 5.0 Reservoir Management Summary................................................................................ 2 Attachments A. Map of Torok Well Locations B. Voidage Balance by Month of Produced Fluid and Injected Fluids 2011 C. Form 10-412 Pressure Report for Torok D. Torok Reservoir Pressure Map —August 2011 t. Annual Reservoir Surveillance Report Pioneer Natural Resources Alaska, Inc. Oooguruk-Torok Oil Pool Oooguruk Development Project 1.0 Progress of the Enhanced Recovery Project During 2011, one well, ODST-46 was drilled, completed and hydraulically fracture stimulated in the Oooguruk-Torok Oil Pool (OTOP). A second well, ODST-39, was drilled in 2011, completed in January 2012, and is awaiting hydraulic fracture stimulation. Sustained production from ODST-46 was initiated in May of 2011 with plans to convert the well to injection for enhanced recovery once production is established from ODST-39 and an Area Injection Order has been issued. An application for an Area Injection Order will be submitted in April 2012, with the intent to begin injection for enhanced recovery later the same year. The locations of the existing OTOP wells are shown on Attachment A. Average daily Torok production for 2011 was 467 BOPD. Cumulative oil production from the OTOP during 2011 was 170 MBO and is 306 MBO since field start-up thru 2011. No water or gas was injected into the OTOP during 2011. Attachment B details the 2011 monthly voidage for the OTOP. 2.0 Results and Analysis of Reservoir Pressure Surveys within the Pool An initial pressure of 2,397 psig (-5,000 TVDSS) was measured in the ODST-46 well on March 24, 2011 prior to fracture stimulating the well on March 28, 2011. A review of the data indicates the pressure was declining at approximately 10 psi per day following the end of the drilling and rig completion operations on March 20, 2011. Subsequently, ODST-46 was shut-in following the initial fracture stimulation and flowback on April 2, 2011 providing a stable initial pressure build up of 2,249 psig (-5,000 TVDSS) after 447 hours. This pressure is consistent with the original OTOP pressure of 2,250 psig (-5,000 TVDSS). Additionally, an approximate six day pressure build up (PBU) test was completed in both ODST-45A and ODST-46 in August of 2011 yielding very similar final pressures, suggesting similar levels of depletion in this initial development area. Attachment C details the surveys and relevant data. 3.0 Results and Analysis of Production and Injection Log Surveys, Tracer Surveys, Observation Well Surveys and any Other Special Monitoring Surveillance equipment was placed in the production liner of ODST-46 to assess oil and water production conformance along the lateral via target fluid tracers which were monitored and analyzed by collecting surface fluid samples over time. Initial data indicate adequate tracer concentrations are being returned in the produced fluids. A quantitative analysis is in progress. Page 1 of 6 4.0 Review of Pool Production Allocation Factors and Issues Over the Year Production from the Oooguruk-Torok, Oooguruk-Kuparuk and Oooguruk-Nuigsut pools is commingled at the surface into a common production line. Allocation between the pools is based on ratio of total production for a pool to the total production for the Oooguruk Unit. The pool allocation factors for 2011 are: Oooguruk-Kuparuk Pool: 50.3% Oooguruk-Torok Pool: 6.6% Oooguruk-Nuiqsut Pool: 43.1% Theoretical production for individual wells for all pools is calculated on a daily basis. During 2011 wells were produced with chokes at 100% most of the time. 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: Minutesproduced 1440 Minutes day xDailyRate(BOPD) welten = TheoreticalDaily Production 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 2011 was 0.92. 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 Oooguruk-Torok, Oooguruk-Kuparuk and Oooguruk-Nuiqsut reservoirs, respectively. Subsurface development of the Oooguruk Unit is done with dedicated development wells to the Oooguruk-Torok, Oooguruk-Nuiqsut and Oooguruk-Kuparuk oil pools with no subsurface commingling. Unitized substances produced from the three oil pools are commingled on the surface. As of January 2012, there are two producing Torok wells, one of which, ODST-46 is a pre - produced injector. One additional producer, ODST-39 has been drilled and completed, and will be completed and placed on production in 2012. Injection will commence into ODST-46 after review and approval of an Area Injection Order for the OTOP. Page 2 of 6 ATTACHMENT A Map of Torok Well Locations Page 3 of 6 ADL379301 ADL389956 ADL389955 ADL389960 ADL389959 ADL389958 ADL389954 ADL389953 ADL389950 ADL389949 ODST OD T-39 ADL355037 ADL35 6 r S 5A i � Ll ADL389952 ADL389951 Legend DL355039 ADL355038 Torok PA j LW+- Unit Boundary 0 Lease Boundary 1:3 Township Boundary Miles 0 0.5 1 2 4 Page 3 of 6 ATTACHMENT B Voidage Balance by Month of Produced Fluids and Injected Fluids 2011 Produced Fluids Injected Fluids Net Year Total Total Year Cum since Import Gas, Water. Injection, Water, Voidage, Cum, start-up, Month Oil, MRB Free Gas, MRB MRB MRB MRB MRB Cum Since Start -Up -17 0 0 0 0 634 Jan -11 9 0 2 12 12 646 Feb -11 14 3 6 23 35 669 Mar -11 12 0 4 16 51 685 Apr -11 6 6 5 17 68 702 May -11 18 21 6 45 113 747 Jun -11 26 46 6 78 191 825 Jul -11 22 56 5 82 273 907 Aug -11 14 35 1 50 323 957 Sep -11 18 37 4 59 382 1016 Oct -11 19 37 7 63 445 1079 Nov11 16 28 6 50 495 1129 Dec -11 13 23 4 40 535 1169 2011 Totals 187 291 57 535 Injected Fluids Page 4 of 6 Net Injection (Injection - Production) Net Year Total Year Cum since Formation Import Gas, Water. Injection, Cum, start-up, Gas, MRB MRB MRB MRB MRB MRB -669 -16 -51 -685 -17 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Page 4 of 6 Net Injection (Injection - Production) Net Year Cum since Injection, Cum, start-up, MRB MRB MRB -634 -12 -12 -646 -23 -35 -669 -16 -51 -685 -17 -68 -702 -45 -113 -747 -78 -191 -825 -82 -273 -907 -50 -323 -957 -59 -382 -1016 -63 -445 -1079 -50 -495 -1129 -40 -535 -1169 -535 ATTACHMENT C 2011 Form 10-412 Pressure Report for Torok (Revised) Page 5 of 6 STATE OF ALASKA ALASKA OIL AND GAS CONSERVATION COMMISSION RESERVOIR PRESSURE REPORT 1. Operator Pioneer Natural Resources Alaska 2. Address. 700 G Street. Suite 00-0, Anchone e, AK 995C1 3. Unitor Lease flame. Ocoguruk 4. Field and Pool S,. Datum Reference 000uruk-7orok Undefined 5000 0. 011 Gravity 29 7. Gas Gravay 0,7 E. Well Name and 9. API Ilumlter Number SOXYI*OCXX)OOOC,X NO DASHES 10. Type 11. AOGCC 12, Zone 13. Perforated 14. Final Test 15. Shut -In 18. Press.17, B.N. laDepth See Poolcode Intervels Date 'Time, Hours Surv. Type -amp. Too, TVDSS Instructions Top - Bottom see TVOSS instructions for codes) 19. Final Observed Pressure at Tool Depth 20. Datum 21, Pressure 'VOSS flnpult Gradient.pvft. 22. Pressure at Datum (eali OBST-46 50703206310000 0 57817E Torok 4919-5005 324/11 InHlal SBHP' 124 4682 2242 6000 0.49 2,317 ODST-46 50703206310000 0 Ela, 175 Torok. 4911-5005 420111 Initial PBU 129 411.82 2141 1000 1 03° 2,232 ODS7-4EA 50703205770100 0 576176 Torok 4944.5117 &'23/11 141 PBU 131 401€ 1100 6000 035 1,58` ODST-4cs 50703206310000 0 576175 Torok 4911-5005 8123111 135 PBU 121 4M 1447 5000 035 1,56,0 `Recorded reservoir pressure prior to flowing back well; declining 10 p%Vcay; 9A ppg completion brine in •well. 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. Signature Title Printed Name M Theresa Williams Date Staff Operations Enijineer Page 5 of 6 ATTACHMENT D Torok Reservoir Pressure Map — August 2011 ATTACHMENT D Torok Reservoir Pressure Map —August 2011 4.4 `T CIL F f- 4boomr E. 470000F f 4#ot40f F, s 01_11`KIIII N 0030000F N U01COOPFNm 44 Pioneer Natural Resources Alaska 1:63360 August 2011 Torok -4 Reservoir Pressure KILOMETRES I L.;�1 I I DOF F UGUGOF F 1111L.W1,,,a,, 11 1_.._,. � NAD2T 1 Alaska zone 4 (E PSG 26734} Transverse Mercator Clarke 18116spharoid Nah,ral oog in; 11" OD COW. 54 DO CON) ALASKA RTATF PI..ANF 70NF 4 Page 6 of 6 095000OF N vtl.*.r,)UO K