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Home My WebLink About2014 Northstar Oil PoolH Hilcorp Alaska, LLC July 24, 2015 Cathy Foerster, Chairman Alaska Oil & Gas Conservation Commission 333 W. 7`h Avenue, Suite 100 Anchorage, Alaska 99501-3539 Post Office Box 244027 Anchorage, AK 99524-4027 3800 Centerpoint Drive Suite 100 Anchorage, AK 99503 Phone: 907/777-8414 Fax: 907/777-8580 dduffy@hilcorp.com RE: NORTHSTAR UNIT, NORTHSTAR FIELD, NORTHSTAR OIL POOL, STATE OF ALASKA, 2014 ANNUAL RESERVOIR REVIEW Dear Commissioner Foerster: In accordance with Conservation Order No. 458A, Hilcorp Alaska, LLC ("Hilcorp"), as Operator, hereby submits for your review the following Annual Reservoir Review for the Northstar Field. This is the 14`h Annual Reservoir Review and corresponds to events during the 2014 calendar year. Note that the Northstar Field has been on production since November 2001. A. Progress of Enhanced Recovery Proiect and Reservoir Management Summary During 2014, no new wells were drilled or sidetracked in the Northstar Unit. Therefore the locations of all the wells in the Northstar Unit have remained unchanged. Production and injection statistics are summarized in Table 1. Average daily oil production from the Northstar field was 7,382 bopd and average daily gas injection was 484.9 mmscfpd. The reservoir voidage balance values reported do not include oil production from satellite well NS34A or Kuparuk zone production from well NS08. During 2014, gas injection was calculated to be 4,369 thousand -reservoir barrels (MRB) more than reservoir voidage. At year end, the reservoir overall cumulative voidage replacement ratio was 1.019. The average of reservoir pressure control for 2014 was 5,087 psia. Hilcorp became the official Operator of the Northstar Field effective November 18, 2014. As a result, the historic reservoir simulation model developed by the previous operator will no longer will be utilized in the enhanced recovery. Hilcorp will commence building a reservoir simulation model, beginning with the Ivishak reservoir. Table 1: NORTHSTAR FIELD 2014 OVERVIEW STATISTICAL SUMMARY WELL STATISTICS Produced Fluids As of 12/31/2014 Full year (1) As of Dec -14 (2) Producers 18 18 Injectors 8 8 NOTES: (1) Well count data reflects ONLY those w ells w hich contributed to productiontinlectlon during the respective year (2) Active wells as of December 2014 PiloOPurge PRODUCTIONIINJECTION STATISTICS Cumulative Start - Up through Production 2014 12/31/14 Oil (BBL) 2,695,231 162,315,290 Gas (MCF) 176,994,009 1,849,915,768 Water (BBL) 3,944,804 53,954,089 Injection Free Gas, Water (BBL) into NS10 & NS32 Disposal Well 6,342,338 60,756,338 Gas (MCF) 189,152,448 2,042,447,448 Balance (excludes satellite well NS,34A and NS08 Kup oil Production) Cum, start-up, Cum Production (MRB) 237,613 1,354,424 Cum Injection (MRB) 241,982 1,379,495 Oner/Under (MRB) 4,369 25,071 DAILY AVERAGE RATE DATA 2014 MRB Gas, MRS Production MRB MRB Oil, BOPD 7,384 MRB Gas, MCF/D 484,915 10,878 Water, BWPD 10,808 11,477 Injection 11,275 478 Water, BWPD 17,376 1,269,134 Gas, MCFPD 518,226 25,712 AVERAGE RESERVOIR PRESSURE 543 9,955 A%erage of surreys obtained in 2014 5,087 psia B. Voidage Balance by Month of Produced Fluid and Iniected Fluids - 2014 Page 2 Produced Fluids Injected Fluids Nethijection (Injection - Pmducdon) PiloOPurge Cum Total Cum since Formation /Flare & Total Year Cum since Net Yew since Free Gas, Water, Voidage, Year clad -up, Gas, Import Injection, Cum, start-up, Injection, Cum, start-up, Month OII. MRB MRB MRB MRB Cum, MRS MRB MRB Gas, MRS MRB MRB MRB MRB MRO MRB Jan -2014 598 10,878 364 11,477 11,477 1,243,422 11,275 478 11,753 11,753 1,269,134 277 277 25,712 Feb -2014 543 9,955 335 10,498 21,975 1,20,920 10,315 443 10,759 22,512 1,279,892 260 537 25,972 Mar -2014 585 10,973 346 11,558 33,533 1,265478 11,361 492 11,853 34,365 1,291,745 295 832 26,268 Apr -2014 453 8,336 318' 8,789 42,321 1,274,266 8,636 381 9,017 43,382 1,300,762 228 1,061 26,496 May -2014 491 10,119 365' 10,610 52,931 1,284,876 10,444 3 10,441 W,,823 1,311,203 -169 892 26,327 Jun -2014 451 9,312 347 9,763 62,694 1,294,639 9,611 -1 9,611 63,434 1,320,814 -153 740 26,175 JuIQ014 450 9,343 362 9,793 72,487 1,304,432 9,641 -2 9,639 73,073 1,330,453 -154 586 26,021 Au9-2014 445 9,427 347 9,672 82,360 1,314,305 9,722 -1 9,722 82,795 1,340,175 -150 435 25,871 Sep -2014 444 9,623 343 10,067 92,426 1,324,371 9,917 -1 9,916 92,711 1,35Q092 -150 285 25,720 Oct -2014 437 9,182 341 9,620 102,046 1,333,991 9,472 -13 9,460 102,171 1,359,551 -160 125 25,560 NO,2014 474 8,185 311 8,658 110,704 1,342,649 8,499 4 8,495 110,666 1,368,046 -164 -38 25,397 Dec -2014 663 11,022 375 11,685 122,389 1,354,334 11,462 -7 11,455 122,120 1,379,501 -230 -269 25,166 2014 Totals'. 8,034 116,355 4,154 122,389 1 120,356 1,765 122,120 1 -269 Page 2 C. Summary and Analysis of reservoir pressure surveys within the pool Static bottom hole pressures collected in 2014 are summarized below. These pressures have been included with the historical Ivishak reservoir pressure data and are graphically represented in the next figure. Page 3 STATE OF ALASKA ALASKA OIL AND GAS CONSERVATION COMMISSION RESERVOIR PRESSURE REPORT 1. Opnalor: lilcoep Alaska, LLC 2. Address: 3800 Cod! o...int Or, Anchorage AK99W3 3. bettor Lease W. Ibrl Wit 4. Rod and Pod: Northster FieldiNorthslar Ql Pool S. WMm Refaonce : A1,100 6. Q1 Quity: 7. Gas QaMty: 42 Bd9 8. 0CI1 Nacre and Weber: e. AN horber SowWIXBxxxxBH W lAtRE5 10 Type See Insured. 11. AOGCO Pod WeriewaR 13. perforated Top Bdbmwm id.(dTest Wte 15.Shubm IIoe,Hoae 16. Ress. Surv.Type (see nsbucWrs for codes) IL B.R Terry. 18. Wplh TooINC6S 19. first Observed Resaure of Tod cope, 20. We. 2LBessme TeWtihnpu6 Qefterd,11t. 22.Ressrreat WMm(ea9p,l9 NSW 50029232440000 O 5901110 1096741085 3110/14 37 SBHP 255 11000 5046 111011 0.11 505] NSW 5X29223080000 O 590100 dKupawk 10900-11099 WW14 28 SBHP 255 11X0 5048 11100 0.10 5058 NS08 5W2923W8WW O 590100 8924-8962 V20/14 48 Other 191 WU 4023 WW 0.26 41W NS08 5X2923W8WW O 5W100 8924-8962 6122/14 48 Other 187 86M 3948 WW 0.26 4034 NS08 SX2923W6XX O 50100 Kupamk 8924-6962 8131114 46 Other 167 M34 $914 00 0.26 4" NS11 5X2923303WW O 5W100 INshak 10980-11050 NW14 31 SBHP 256 11X0 5014 111W 0.43 5057 NS18 5X29231021)(IX O 5W100 INshak 10971-11047 NW14 40 SBHP 254 11000 5W3 111W 0.10 51W NS21 5X2923126WW O 5W100 Mshak 10998-11110 3/5/14 62 SBHP 252 11X0 5073 111W 0.11 5064 NS28 5X2923248X0 O 50100 Idshak 11052-11095 3131114 300 Other 242 10480 4972 111W 0.10 5,199 NS28 I 5X292324800 O SW100 I INshak 1 11052-11095 6/25/14 X24 Other 1 242 10480 4975 111W 0.10 5102 NS28 6X2923248WW O 5W100 Ishak 11052-11095 9122114 8160 Other 242 10480 4972 111W 0.10 5X9 NS30 5(102923293C)CX O 5W100 INshak 10857-11021 9117114 30 S8HP 257 1100 4971 411W 0.33 5X3 NS33A 5W292332501X O 5W100 INshak 11027-11070 3/4/14 26880 SBHP 261 11X0 5022 111W 0.24 5048 NS34A 5X2923X101X O 50101) Idshak 11049-11091 9/18/14 31 SBHP 257 111W 4953 111W 0.43 4953 W—eats: 23.A1 testa reputed herskiwers breds It accordancew Br the appicade rvbs,reg0ster, artl molester, of Me Alsebe 01 and Gas C ssrvaten Confessiot. thereby c ertty Mat Ne f we9on0 4 true and cwreat to M e best of" krow kNOe. Slenabes TO. forted Nana Chris Kanyer Wm NoNM1star ResenOir Enline,r July 13, 2015 These pressures have been included with the historical Ivishak reservoir pressure data and are graphically represented in the next figure. Page 3 5250 5225 5200 a 5175 5150 E 5125 y 5100 w 5075 a .0 5050 5025 W 4975 NSO6 New x 11316 x New • N312 ♦ NS13 IIS14 NSIS • 11516 11317 . NSte N810 New x NS21 • Hem • NS23 NSN Men - NSU • Hem • N331 • NSW • NSR • N311 • New • NS3 TAveWePres 111111111111! Percentage of Now from/to interval. Blank intervals are not perforated. Well Name Well Type Date Log Type 11111111111111111111111111111111111111111111 IHshak Zone C1 kishak Zone B NS09 Producer 3121/2014 S/T/P/Gradio 0 0 80 20 NS13 Producer 3123/2014 S/T/P/Gradio 0 0 0 1 100 l I11lli��li�l�siillll1111111111111111111111111111111111111 l l l l l l l l l l l �;� 111111111111111111111111111111111111111111 I111I11��''Ol�ill Illlli�lll 111111 lllllllll ll11111111111 111 lllllllillllllil Illllll�llllll 111 lllliil1111111111 IIIIIIIIILIIIiill0�l1!^li�i ��i�lll�ll��N�llil!�IILisllill Illllllllllllllllll��»l�l11i1111��liliE'il►ill111111111::1 Illllllllllllllllliiiillilillliillllllllllliliiiiiii01d111 IIIIIIIIIIIIIIIIIIIIIIIIIII111111111111111111111111111111 Illllllllllllllllllllllllllllllllllllllllllllllllllllllil 11111111111111111111111111111111111111111111111111111111 The data shows a decrease of reservoir pressure during 2014. The average Northstar field reservoir pressure for 2014 is 5,087 psia, down 22 psia from the 2013 average. Please note that well NS -34A is a satellite well to the main field and the reservoir pressures reported from NS08 during 2014 are from the Kuparuk Reservoir. D. Results and Anatysis of Production and Iniection log surveys, tracer surveys, observation well surveys and any other special monitoring Two new production profiles were obtained in 2014. The following table summarized these profile results. The gas tracer program, initiated in 2004, was concluded in 2008 and there are no further updates for this reporting period. E. Review of pool production allocation factors and issues over the prior year Theoretical production is calculated for each Northstar producing well on a daily basis. January 1, 2014 through October 31, 2014 Allocation Method (Prior Operator's Allocation Method) A well's theoretical production is calculated using average wellhead flowing pressure and hours on production as follows: Page 4 Percentage of Now from/to interval. Blank intervals are not perforated. Well Name Well Type Date Log Type IHshak Idshak IHshak kishak Shublik D Zone E Zone D Zone C3 Zone C2 IHshak Zone C1 kishak Zone B NS09 Producer 3121/2014 S/T/P/Gradio 0 0 80 20 NS13 Producer 3123/2014 S/T/P/Gradio 0 0 0 1 100 The gas tracer program, initiated in 2004, was concluded in 2008 and there are no further updates for this reporting period. E. Review of pool production allocation factors and issues over the prior year Theoretical production is calculated for each Northstar producing well on a daily basis. January 1, 2014 through October 31, 2014 Allocation Method (Prior Operator's Allocation Method) A well's theoretical production is calculated using average wellhead flowing pressure and hours on production as follows: Page 4 hoursproduced _P X I—(-fl-ov X `c'aof — aheore(ical 24 Pvhsi Where: hoursprodoeed = hours on line Pwhf= average wellhead flowing pressure Pwh:1= shut-in wellhead pressure n = flow exponent % f = absolute open flow of well with Pwhf = 0 psi Qtheoreticai = theoretical production The input parameters (n, Qaof and Ph1;) for each well are determined from well test data and systems analysis and are reviewed each time new test data becomes available. The actual total production for a day is divided by the summation of the theoretical production from each well to calculate a daily allocation factor. This allocation factor is then multiplied by each well's theoretical production to calculate allocated production. November 1, 2014 through December 31, 2014 Allocation Method (Hilcorp's Allocation Method) A well's theoretical production is calculated using metered field volumes and hours on production as follows: Gas Allocation Gross Produced Gas = total return metered at test separator. Net Produced Gas = Gross Produced Gas - Gaslift Gas. Theoretical Produced Gas = all well tests Net Produced Gas prorated by the month. (Proration calculation will include adjustments for shut in or downtime periods) Field Gas Injection = metered prior to injection Total Net Produced Gas = Field Gas Injection + Fuel Gas + Flare Gas + PPA Gas - Buy Gas (Buy Gas = imported or Caribou Crossing acquired gas). Total Net Produced Gas Theoretical Produced Gas = Gas Allocation Factor Gas Allocation Factor x Theoretical Produced Gas (individual well) = Allocated Gas (individual well). Oil Allocation Actual Field Oil Production = oil volume metered by LACT (sold/delivered to Northstar crude oil pipeline) (Adjusted for BS&W, temperature, and AN gravity in accordance with API standards and BSEE regulations.) Gross Produced Oil = total return metered at test separator. Theoretical Well Oil Production = all well tests Gross Produced Oil prorated by the month. (Proration calculation will include adjustments for shut in or downtime periods) Theoretical Field Oil Production = Sum of Theoretical Well Oil Production Field Natural Gas Liquid (NGL) Production = metered prior to commingling with oil Actual Field Oil Production - Field NGL Production Theoretical Field Oil Production = Oil Allocation Factor Oil Allocation Factor x Theoretical Well Oil Production = Allocated Oil Production (individual well). Water Allocation Page 5 Actual Field Water Production= water volume metered prior to injection disposal Net Field Water Production = Actual Field Water Production — Metered Grey Water Gross Produced Water= total metered at test separator. Theoretical Well Water Production = all well tests Gross Produced Water prorated by the month. (Proration calculation will include adjustments for shut in or downtime periods) Theoretical Field Water Production = Sum of Theoretical Well Water Production Net Field Water Production Theoretical Field Water Production —Water Allocation Factor Water Allocation Factor x Theoretical Well Water Production =Allocated Water Production (individual well). Northstar field allocation factors for November and December 2014 averaged 0.82 for oil, 1.02 for water and 1.01 for gas. Oil allocation factor was low due to increased Field NGL production in winter months. F. & G. Future Development Plans & Review of Annual Plan of Operations and Development Hilcorp will pursue increased unit production through well intervention projects, infrastructure and facility repairs, and other optimization opportunities as they arise, including the evaluation of shut-in wells for potential return to service or utility No drilling activities are planned at Northstar within the 2015 calendar year. The mobilization of a workover rig to the Northstar Island during the 2015 summer barging season is currently under evaluation for the NS -18 recompletion project. Projects planned for the 2015 calendar vear: • Fix surface casing leak in the NS -22 well; • Abandon the Ivishak reservoir in the NS -18 and recomplete to the Kuparuk sand; • Abandon the Ivishak reservoir in the NS -24 well and test the Sag reservoir; and • Convert NS -28 into a gas injector in the Ivishak reservoir. This project will reduce injection pressure in the field and allow for compressor horsepower optimization. Hilcorp will conduct a full field study of the Northstar Unit. This may include re -mapping all productive and potentially productive horizons, building complete well histories for every well in the Unit, reviewing all production and injection data, material balance calculations, and researching all past engineering, geological, and geophysical work. A reservoir simulation model will be developed, beginning with the Ivishak reservoir, in order to optimize injection by contacting under -swept pore volume. Sincerely, /�[/�/j+, Chris Ka yer i� Reservoir Engineer- Northstar Page 6