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Home My WebLink About2011 Schrader Bluff Oil Pooleni April 10, 2012 Commissioner Cathy Foerster Alaska Oil & Gas Conservation Commission 333 West 7th Avenue, Suite 100 Anchorage, AK 99501 Re: Annual Reservoir Surveillance Reports Nikaitchug Schrader Bluff Oil Pool Nikaitchuq Unit, North Slope Alaska Dear Commissioner Foerster: eni us operating eni us operating co. inc. 3800 Centerpoint D -., Suite 300 Anchorage, AK 99503 — U.S.A. Tei. 907-865-3300 Fax 907-855-3380 P ec ti eR��91D1 G,GG P The Alaska Oil and Gas Conservation Commission (AOGCC) approved pool rules for the Schrader Bluff oil pool within the Nikaitchuq Unit as Conservation Order 639. Rule number 12 of the order requires tha filing ui annual surveiiiance reports, which are attached hereto. Please let us know if you have any questions or require additional information regarding these reports. Sincerely, —9. �- Robert A. Province Land Manager -Alaska Attachment us operat*ong 2011 Annual Reservoir Surveillance Report Schrader Bluff Pool Nikaitchuq Field 2011 Annual Reservoir Surveillance Report 4/9/2012 Table of Contents 1.0 Well Drilling and Enhanced Recovery ....................................................................... 2 Figure 1 - 2011 Well Placement Schedule at Nikaitchuq Field ................................... 2 2.0 Reservoir Pressure Map, Results and Analysis of Reservoir Pressure Surveys with the Nikaitchuq Schrader Bluff Pool.................................................................................. 3 3.0 Review of Pool Allocation Factors and Issues over the Year 2011 ........................... 3 4.0 Reservoir Management Summary ............................................................................. 4 5.0 Results of Tracer Surveys Conducted in the Year 2011 ............................................4 Figure 2 - 0111-01 DTS Data vs. Depth...................................................................... 5 Figure 3 -Oil 1 -01 Therma Cool Back Injection Solution ............................................ 6 Figure 4 - 0107-04 DTS Data vs. Depth...................................................................... 6 Figure 5 - 0107-04 Therma Cool Back Injection Solution ............................................ 7 6.0 Voidage Balance by Month of Produced Fluids and Injected Fluids on a Standard and Reservoir Volume Basis with Yearly and Cumulative Volumes ................................ 7 Figure 6 - Pattern 0111-01 Voidage Balance at Year End 2011 ................................. 8 Figure 7 - Pattern 0107-04 Voidage Balance at Year End 2011 ................................. 8 Figure 8 - Pattern 0I-02 Voidage Balance at Year End 2011 ..................................... 9 Figure 9 - Pattern 0106-05 Voidage Balance at Year End 2011 ................................. 9 7.0 Future Development Plans, Including an Estimated Development Schedule, Progress Report and Basis of Timeline for the complete Pool development.................10 List of Attachments: Attachment A - Nikaitchuq Development Pattern Attachment B - 2011 Reservoir Pressure Report for Schrader Bluff Attachment C - Simulation Pressure Map at December 31, 2011 Attachment D - Voidage Balance by Month of Produced Fluids and Injected Fluids in 2011 Attachment E - Adding Injection Wells in the OPP Area in 2012; Full Injection Pattern Complete by July 2012 Attachment F - Simple Drilling Schedule 2011 Annual Reservoir Surveillance Report 1.0 Well Drilling and Enhanced Recovery 4/912012 During 2011, a total of eighteen wells (12 oil producers, 4 water injectors, one source water well and a disposal well) were placed in service at Nikaitchuq field (see Figure 1 - 2011 Well placement schedule at Nikaitchuq Field). With the exception of oil well SP18-N5 and disposal well SD37-DSP1, which were drilled and placed in service at offshore Spy Island pad (SID), all the wells that were placed in service in 2011 were drilled from Oliktok Point onshore drilling pad (OPP). The disposal well, OP26-DSP2, source water well, OP23-WW02, together with seven oil wells (OP -I2, OP03-05, OPO4-07, OP08-04, OP12-01, OP05-06 & OP17-02) and one water injector, 0I11-01, were drilled in 2010 or earlier. The remaining six oil wells (OP10-09, OP16-03, OP14-S3, OP09-S1, OP18-08 & SP18-N5) and two water injectors (0I07-04 & 0I06-05) were drilled in 2011. Oil producer, OP -I2 was converted from an oil producer to a water injector in November 2011. ATTACHMENT A is a map of the Nikaitchuq Development Pattern and it shows the locations of the wells drilled and green and blue lines for future locations of oil producers and water injectors, respectively. Figure 1 - 2011 Well Placement Schedule at Nikaitchuq Field Service Well Type Placement Date Comments OPO4-07 Oil Producer 30 -Jan -11 OP03-05 Oil Producer 5 -Feb -11 OP12-01 Oil Producer 7 -Feb -ii OP08-04 Oil Producer 7 -Feb -11 OP17-02 Oil Producer 8 -Feb -11 OP -I2 Oil Producer 8 -Feb -11 OP05-06 Oil Producer 9 -Feb -11 OP10-09 Oil Producer 20 -Mar -11 OP16-03 Oil Producer 24 -Apr -11 OP14-S3 Oil Producer 20 -Jun -11 OP09-S1 Oil Producer 24 -Jul -11 OP18-08 Oil Producer 13 -Sep -11 SP18-N5 Oil Producer 24 -Nov -11 First oil well at Spy Island OP11-01 Water Injector 15 -Apr -11 0I07-04 Water Injector 15 -Apr -11 OP -I2 Water Injector 3 -Nov -11 Converted into an injector 0I06-05 Water Injector 20 -Nov -11 SD37-DSP1 Disposal 23 -Oct -11 Spy Island disposal well 2 2011 Annual Reservoir Surveillance Report 4/9/2012 Overall, 2011 was dominated by well drilling at a pace of approximately one well every month and prudent waterflood management. Good reservoir management strategies were used to begin the anticipated long life of waterflood at Nikaitchuq field. 2.0 Reservoir Pressure Map, Results and Analysis of Reservoir Pressure Surveys with the Nikaitchuq Schrader Bluff Pool Prior to placing new wells in service, initial reservoir pressures were measured in all the wells. Additionally, Pressure Build Up (PBU) for some oil producers and Pressure Fall Off (PFO) for one injector analyses were conducted during 2011. ATTACHMENT B - 2011 Reservoir pressure report for Schrader Bluff shows a summary of these pressure surveys. Results from the PBUs indicated that reservoir pressure was being drawn down around the wellbores compared to the original static pressure. Positive water injection support is evident in some oil producers around the water injectors. Development of waterflood patterns at OPP will be completed by July 2012 after drilling and placing injectors OI15-S4, SI29-S2, OI01-1A-06 & 0120-07 in service. Reservoir pressure map of the Schrader Bluff at year end 2011 is shown in ATTACHMENT C. 3.0 Review of Pool Allocation Factors and Issues over the Year 2011 Production from all wells producing from the Schrader Bluff pool is commingled at the surface into a common production line. Theoretical production for individual wells from the pool is calculated on a daily basis by using well test allocation. Daily theoretical production for a well was calculated using the last valid well test and the amount of time a well was on production for a given day. For example, if we had a valid well test on the first of the month and another on the fifth of the month, the allocation factor for that well will be calculated on the first through the fourth of the month using the test on the first. Subsequently, the allocation factor will be recalculated on the fifth using the new valid test measured on the fifth. On the monthly level, our AVOCET Manager Production software sums up the allocated volumes from each time period between valid well tests. (Minutes on production/1440 minutes/day)*Daily Rate (stb/d)welltest=Theoretical Daily Production The daily allocation factor for the field 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 1.03. This confirms that our well allocation method is reasonably accurate. 2011 Annual Reservoir Surveillance Report 4.0 Reservoir Management Summary 4/9/2012 ENI commenced injection into the Schrader Biuff reservoir in 201i. As shown in Figure 1, the first two injection wells (0I11-01 & 0107-04) began injection into the Schrader Bluff Pool on April 15, 2011. Prior to this date, there were eight oil producers (OP03-05, OPO4-07, OP12-01, OP08-04, OP17-01, OP -I2, OP05-06 & OP10-09) already on production. As of January 2012, there were 12 oil producers (11 from OPP and 1 from SID) on production and 4 water injectors (all OPP injectors) on injection. Oil production from wells receiving injection support from both sides of the line pattern (OP17-01, OP12-01, OP08-04) has improved significantly. Wells receiving support from one side of the line pattern (OPO4-07, OP03-05 & OP05-06) has also gained some improvement in oil production. None of the oil producers experienced water breakthrough during 2011 and the timing of water breakthrough suggested from the Nikaitchuq field reservoir simulation is couple of years away. At the end of the year 2011, cumulative water injected into the Schrader Bluff Pool was an equivalent of 18% of the fluid production offtake. However, at the pattern level, well offtake was in balance with water injection. The eventual reservoir management goal for the Schrader Bluff pool will be to infill the entire OPP and SID patterns with water injectors. This will help to inject enough water into the pool and increase reservoir pressure to reasonably high level and help boost oil production as well as overall field oil recovery. 5.0 Results of Tracer Surveys Conducted in the Year 2011 Resman oil & water tracers were installed in OP05-06 & OP17-02. Samples were taken from the wells in September 2011 and analyzed to investigate the effective contribution of sections of the lateral (heel to toe) to overall oil production from the wells. Results from the sample analyses taken from the two wells confirmed that all sections of the laterals were contributing in varying degrees to total oil production. ENI installed Inflow Control Devices (ICDs) and Distributed Temperature Sensing (DTS) using Fiber Optics in two injection wells at OPP, 0I11-01 & 0107-04. The ICDs function by introducing a controlled pressure drop along the entire lateral length of the injectors and compensate for pipe friction drops and/or permeability contrast along the laterals. They are intended to equalize pressure profiles along the entire lateral and encourage oil production from heel to toe of the horizonatal oil producers they provide reservoir support for. Analysis of the DTS data will help to provide a glimpse of the temperature profile of the water injection into the reservoir along the entire lateral of each injector. Interperative DTS data requires a designed shut-in and a restart to measure the transient temperature response required for DTS analysis. ENI took advantage of a field downtime that occurred between 31St August and 2nd September to capture analyzable DTS data. The 4 �l� 2011 Annual Reservoir Surveillance Report 4/9/2012 measured temperature response was analyzed with the help of Schlumberger`s Therma software. Qualitatively, the overall results showed injection profiles from heel to toe for both injectors. However, quantitatively, the results indicated that the inflow profile was not uniform, but rather that there was an interval of higher injectivity between 9,240 - 10,740 ft for 0I07-04. For 0I11-01, the heel area from 6,000 - 6,890 ft and near the toe at 8,900 - 9,800 ft showed higher injectivity. Figures 2-5 show DTS data vs depth and Therma cool back injection solution plots for 0I11-01 & 0I07-04. Figure 2 - OR 1-01 DTS Data vs. Depth 2KM i 116m i OA -2 Injectlon July I.em Start of Sl IYOP _ SI+24hrs SI +4Mrs 116-06 l6m 66x6 `A,....rte s i ono !1 Permafrost 46m xss Horner SI �aShale +o/WpNI ln«m z I-7q,tlrt7alryrm 61 Ispm Y�al A. geothermal I. ,lm InmVJV Gamma Ra Ir I'' , ' k, t:„ti 0.60 1,600.06 1.x.4' ism 4616m 6p06O1 e.01109 1p06Rx 46®6L0 1y1106m I6p00L0 em 5 2011 Annual Reservoir Surveillance Report Figure 3 - OU 1 -01 Therma Cool Back Injection Solution T ac5M OTS Si Therma model DTS I +24hrs I injection Injection Ju u Injection Therma 750° profile model 81 W.0 Geothermal MW Gamma Ray MW -A SIOULM 6,MLW 7j®m Figure 4 0107-04 OTS Data vs. Depth % eni OA -1 x OA -2 OA -3 1pm• E" Shale csa <a —agawaeNM 111 I= M MOOM, MOM -4—RW 4/9/2012 lase IVA Injection July Inm S Start of 51 MAP SI +2b, logo MW saoe Permafrost Horner Sl 3ULW geothermal wm Gamma Ray 210" IAOW % eni OA -1 x OA -2 OA -3 1pm• E" Shale csa <a —agawaeNM 111 I= M MOOM, MOM -4—RW 4/9/2012 2011 Annual Reservoir Surveillance Report Figure 5 - 0107-04 Therma Cool Back Injection Solution 1,WO.W _ . _ ___ _ _t___ .. — __ _ ._.- ___ — J Therma model DTS 1d5ID +Y4hrsl injection Injection I Yw.w 1,5w,w / July IW.W 1,2W.00 vo.W tW.W e6.W 6 MCC ' . ':� W.60 P Injection Therma profile model S! Geothermal � 70.66 30 Gamma Ra Y ! �O0 30, van w ....... ........� ... .._ _... ... _ «� �..�,�....� ... ._. _ .. _r+rv_t-�--`.�'e y:'.•.?F.r-a-..' 60.W l 0.00 5 WO.W 6AWA0 7.WO.W 8,6=00 S WOAD 1$OW.00 11.WO.00 12AW.W 4/9/2012 6.0 Voidage Balance h;; Month of Produced Fluids and Injected :quids on a Standard and Reservoir Volume Basis with Yearly and Cumulative Volumes During 2011, a total of about 2 million barrels of oil were produced from the Nikaitchuq field at an average daily rate of approximately 5500 bopd. Approximately 345 thousand barrels of water was injected during the year. ATTACHMENT D shows a summary of the produced and injected fluids as well as the net injection during the year 2011. Figures 6-9 show a summary of produced and injected fluids at the pattern level. eni 7 2011 Annual Reservoir Surveillance Report 4/9/2012 Figure 6 - Pattern 0111-01 Voidage Balance at Year End 2011 Parameter Value Cumulative Prod Voidage - krb 222 Cumulative Inj Voidage - krb 173 Instantaneous Prod Voidage - rb 866 Instantaneous Inj Voidage - rb 734 Instantaneous VRR 0.85 Cumulative VRR 0,78 Figure 7 - Pattern 0107-04 Voidage Balance at Year End 2011 Parameter Value Cumulative Prod Voidage - krb 177 Cumulative Inj Voidage - krb 148 Instantaneous Prod Voidage - rb 428 Instantaneous Inj Voidage - rb 560 Instantaneous VRR 1.31 Cumulative VRR 0.84 8 2011 Annual Reservoir Surveillance Report Figure 8 - Pattern 0I-02 Voidage Balance at Year End 2011 4/9/2012 Parameter Value Cumulative Prod Voidage - krb 414 Cumulative Inj Voidage - krb 34 Instantaneous Prod Voidage - rb/d 842 Instantaneous Inj Voidage - rb/d 659 Instantaneous VRR 0.78 Cumulative VRR 0.08 Figure 9 - Pattern 0106-05 Voidage Balance at Year End 2011 Parameter alue Cumulative Prod Voidage - krb 139 Cumulative Inj Voidage - krb 24 Instantaneous Prod Voldage - rb 221 Instantaneous Inj Voidage - rb 581 Instantaneous VRR 2.63 Cumulative VRR 0.17 eni 9 2011 Annual Reservoir Surveillance Report 4/9/2012 7.0 Future Development Plans, Including an Estimated Development Schedule, Progress Report and Basis of Timeline for the complete Pool development Nikaitchuq field development strategy consists of OPP and SID. The onshore development contains dedicated multiphase processing facilities with capacity of 40 Kbopd whereas the SID development is mainly a drilling location from which offshore production will be imported via a sub -sea flowline bundle to OPP. Total production from the Nikaitchuq facility will be exported through a 14 -mile pipeline tied -in to the Kuparuk pipeline, which exports oil to the Trans Alaska Pipeline (TAPS) system. As summarized below, some project milestones were completed in 2011 and others remain to be completed in the coming years. At the end of 2011, the construction of OPP, and the drilling of 11 oil producers, four water injectors, one source water well and one disposal well, were completed at OPP. Also completed at end of 2011, was the construction of SID and drilling of one oil producer and one disposal well, at SID. In 2012, we plan to drill two more source water wells to provide additional water for water injectors at SID and OPP. Additionally, we intend to drill five more water injectors at OPP (two already drilled and put in service at the time of writing this report) to completely infill all the OPP patterns with enough water injectors to support reservoir pressures. ATTACHMENT E is a pressure map at the end of 2011 showing current and future locations of water injectors in the OPP area. Full pattern development with water injectors in the OPP area should improve field balance and stabilize oil production. It is scheduled to be completed in July 2012 with the drilling of northwest outboard injector OP -IIA -I06. We also plan to drill seven oil producers in 2012 (SP27-N1 & SP23-N1, already drilled and put in service), and four water injectors (SI29-S2 already drilled but not put in service at the time of writing this report). Drilling will continue on SID through Octobert 2014 and we plan to drill five oil producers and five water injectors in 2013. In 2014, we will complete drilling by adding five water injectors and an oil producer. ATTACHMENT F shows a simple drilling schedule for the Nikaitchuq field development showing the completion of drilling activities at OPP and SID on August 2012 and October 2014, respectively. lanl 10 Attachment A - Nikaitchuq Development Pattern Nikaitchuq Development Pattern echeader Sluff OA devq(Q pmeni n aom 4= WE emu •.o= 13� ** eni vs operating Ana Attachment B - 2011 Reservoir Pressure Report for Schrader Bluff STATE OF ALASKA ALASKA OIL AND GAS CON SEWATION COMMISSION RESERVOIR PRESSURE REPORT I. OPOa:or. ey 1;e 07a'ati1cc be. 2.kddreas: 3806 CenterPaia RmT. Suite 337, Rnchon a AK 99533 7r LmseNarne: 'l:bcJsty 4. FS®y aid Fw: tJ=atehu-stfrrader BluSSGi: 5. Dater, Pelemgq 3793 & 01 Srayk,: 1s 7. Gas Gravity: .87 'a✓a.3 ama9.A :dux, r. :I:Nnmw MOD000C000M :1.7 7AEr:cS ype 9Re lna:ructioa 11. pool ado n• .c+a:es ;�itavas -aP_ 2ma^."L455 14. a! Teat a mrt-.. r--e,+oars a. um. Type;We `:ts7'uC'atu 1w codes-aoiaa -ero. t Pth o4 TVD SS rna. Umoved pressure to h atun: 1. racun WDS6 l_Vutb Gredlm.. psY1= sues Dawn lea; OP -12 50029233260000 O 561100 Schrader Bluff 3579-3599 02/05/11 Initial SBFP 76 3512 1582 3765 .407 1683 OP -12 50029233260000 0 561100 SchEilderBluff 3679-3599 09101111 42 215L 76 3512 693 3763 437 116132 1 OP03-05 53x29233960000 0 561100 Schrader Bluff 3686-3836 02/05111 Initial SBKp 76 3436 1573 3760 .437 1701 OP03-35 50029233960000 0 561100 Schrader Bluff 3666-3636 09101111 43 PBL 76 3436 8499 3760 .407 1563 - 7 �MM234090000 0 561100r 6 01 It3Q;1 I Initial SBPP 76 3626 1640 .407 1695 OP34-37 50029234393333 0 561100 Schrader Bluff 3780-3901 :9131111 43 PBC: 75 3626 966 3763 .407 1640 01205-06 50029234090000 O 561100 Schrader Bluff 3831-3994 3213x1111 Initial SBHP 77 3717 1889 3760 .437 1706 - 3618-3622 11 Initial HP 74 3059 14 .407 1990 OP 12-31 50029234260000 0 561100 Schrader Bluff 3615-3622 39/31111 43 PBU 74 3059 690 3760 .407 1416 OPOU-34 53a292342700QD O 561100 Scrader Bluff 3629-3706 2Q3 11 I SBHP 76 3483 1527 3760 _437 1708 - MOM 1 4D P d � 1 7 " OP 17-02 50029234310330 O 561100 Schrader Bluff 3523-3555 02105/11 Initial SBHP 77 3465 1559 3760 .437 1739 7-34 500292N3530ap 0 .561100 SchMder B1 3626-3673 SIMI1 66 F 7 3-433 1667 OP 15-09 53023234393300 O 561100 Schrader Bluff 3667-3533 1 31,113111 Initial SBFP 76 3529 1567 3760 .407 1566 01310-09 60329234390030 0 561100 Schrader Bluff 3667-3533 09131!11 40 PBL; 78 3529 960 3760 .407 1562 P1F- 7 3614-3815 06/151 1 Initial SBFP 61 3533 15 7 .407 OP 16-33 50029234473330 O 561100 Schrader Bluff 3614-3615 09/01111 40 PBL 81 3593 956 3760 .407 1461 0P14 -S3 50029234470030 O 561100 Schrader Bluff 3613-3696 06122111 Initial SBFP 82 3593 1592 3760 .437 1695 P_P14-SZl 50529234470330 0 _0111100 uff M1 3-3095 09/01111 43 PB 3593 927 3760 .407 1592 01309 -Si 50029234480000 0 5611DO Schrader BI 3732-3682 07/23111 Initial SBHP 83 499 1562 3760 .407 1688 0pp9_S1 SQ329234480GOD 0 5611 3732-3852 39 31111 40 PLt 83 3499 1592 3760 .437 1688 OPIS-08 50329234,490000 0 515111ppluR 6- __3WUWIIJ Initial SBFp 75 3227 1447 37 1 SP16-N5 53629234530000 0 561100 Schrader Bluff 3B16-3949 11122/11 initial SBFP 94 3900 1783 3760 0.407 172E 23.A:;:es=reported heron were rradelq axarlwee whh tate app:itg6R rum regu;edoatt end,ventotea� aithe l hereby mtiiylha: ate 1dra9019 't:7uaand nrrsc :a the basral ny knaw'ed9e. Sgnatwe Y;.ne3 "tams A'aaka 09 end 13494anasvaYon Ca-iu'On. Tkle 3210 We n Attachment C — Simulation Pressure Map at December 31, 2011 MikaitchLiq Development Pattern 464000 0D= .Mao 490D00 www 5040m S06000 5120w0 546[00 MGM 5:-000 52&M 53'x00 5 00 4 600 1 .,4 1600 11400 T 1300 1_00 1100 l 4 .0 '1.#ka.PTOss�rt hTap At— TF?* e n eno us operating Attachment D -- Voidage Balance by Month of Produced Fluids and Injected Fluids in 2011 eni us operating Produced Fluids Injected Fluids Net bjection. 2011 Cumulative Oil - Free Cas, Water - Total Monthly Fluid Production Voidage - Water Injection - 2011 Cumulative Water Net Water Injection -zou Cumulative Net V M W I 1 O O O O Jan -11 126 O O O Feb -11 134 134 -134 -134 193 0 1 0 0 Mar -11 204 338 -204 -338 152 O 3 22 22 Apr -11 162 500 -141 -478 0 1 36 57 May -11 201 212 712 -176 -655 0 28 85 Jun -11 191 202 914 -174 -829 0 2 38 123 Jul -11 211 223 1137 -185 -1,014 0 2 39 162 Aug -11 196 208 1345 -169 -1,183 0 2 36 198 Sep -ii 173 183 1528 -147 -1330 0 3 41 239 Oct -11 185 197 1726 -156 -1,486 0 5 59 298 Nov -11 163 177 1903 -118 -1,604 0 3 76 374 Dec -11 218 211 21 -1 -1,76o 011 Totals 2 010 O 23 29134 -1 60 eni us operating Attachment E - Adding Injection Wells in the {SPP Area in 2012 Full Injection Pattern Complete by July 2012 Pressure [a? YE201 New injectors; should improve field balEince and stabilize production ImaWn eni1 eno us ®Hestina Nikaitchuq: CP Development i 498000 5®00 502m0 _-0M SOB.= SOB.= 510000 512000 5144WO Me= 516000 0.20000 MM 524000 \ OP09S1 Q� \ 1 2 OP14$2 }} . n 301 OP10-08\ S SEL F2j OPtls-04 V .1 1 DY qp� � 2Q ,9b 7-02 888 j J ON 8.08 xpi\ \ k OP08 OPUS 2QiZ � � '�� 0111-01 12047 [P141 �. \ \O 2 } g 1lb S ! P i) O 4' 1800 1700 PB." 1e05 1500 t 1400 1900 1200 1100 i 1000 $$$ 900 700 am 408000 @00000 MM 804000 SOB000 506000 910000 �T 512000 514000 518000 5,8000 ^SOW mi'0 524= Nikaltehuo Pressure Distribution Maas 0 70°0 MM X065 4M MM ar�.n,e Pr..�.o�r. .:z:sae AI®ke ne Team 12r3112011 Pressure [a? YE201 New injectors; should improve field balEince and stabilize production ImaWn eni1 eno us ®Hestina Attachment F- Simple Nikaitchuq Drilling Schedule eni us operating ..:z �r.. - r aoff C I �..'M�N:y$uL".. _ a 'Op f eni us operating