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HomeMy WebLinkAboutCO 147Conservation Order Cover Page XHVZE This page is required for administrative purposes in managing the scanning process. It marks the extent of scanning and identifies certain actions that have been taken. Please insure that it retains it's current location in this file. L ~ '~- Conservation Order Category Identifier Organizing RESCAN [] Color items: [] Grayscale items: [] Poor Quality Originals: [] Other: NOTES: DIGITAL DATA [] Diskettes, No. [] Other, No/Type OVERSIZED (Scannable with large plotter/scanner) [] Maps: [] Other items OVERSIZED (Not suitable for plotter/scanner, may work with 'log' scanner) [] Logs of various kinds [] Other BY: .,/~ MARIA Scanning Preparation TOTAL PAGES .,,,,._.~¢ Production Scanning Stage I PAGE COUNT FROM SCANNED DOCUMENT: -- PAGE COUNT MATCHES NUMBER IN SCANNING PREPARATION: YES NO Stage 2 IF NO ~N STAGE 1, PAGE(S) DISCREPANCIES WERE FOUND: ~ YES NO (SCANNING IS COMPLETE AT THIS POINT UNLESS SPECIAL ATTENTION IS REQUIRED ON AN INDIVIDUAL PAGE BASIS DUE TO QUALITY, GRAYSCALE OR COLOR IMAGES) General Notes or Comments about this Document: 5/21/03 ConservOrdCvrPg.wpd STATE OFALASKA DEPARYMENTOFNATLRRA~SO~CES DMSION OF OIL AND GAS CONSERVATION Alaska Oil and Gas Conservation Committee 3001 Porcupine Drive Anchorage, Alaska 99501 THE APPLICATION OF UNION OIL. ) CQMP~ OF CALIFORNIA for an ) order allowing the commingling ) of production from the Trading ) Bay Middle Kenai "D" Oil Pool ) and the Trading Bay Hemlock Oil) Pool in Trading Bay State A-2 ) and A-32 well bores. ) Conservation Order No. 147 Trading Bay Field Middle Kenai "D" Oil Pool Hemlock Oil Pool September 22, 1977 IT APPEARING THAT: le The Oil and Gas Conservation Committee published anotice of public hearing in the Anchorage Daily News on August 10, 1977, pursuant to Title 11, Alaska Administrative Code, Section 22.215. . Apublic hearing was held August 23, 1977 at the above address, at which time the applicant was heard. e At the hearing the operator withdrew the referenced request in so far as it applied to the Trading Bay State A-32 well. FINDINGS: lo Approximately 75% of the ultimate recovery of the Trading Bay Field has been produced todate. . The last usable platform slot for drilling is currently being utilized to drill the Trading Bay A-20 well. 3. Mechanical efforts to separate the production streams have been 'unsuccessful .due to tubingerosion. . It is not economically feasible to correct the tubing erosion problem and mechanically separate the Middle Kenai "D" and Hemlock Pools in well A-2. 0 Pressures are similar in the Middle Kenai "D" and Hemlock Pools and crossflow would not be anticipated. Conservation Order No. 147 Page 2 September 22, 1977 CONCLUSION: . Con, mingling of the production from the referenced pools in the referenced wellsmay result in the recovery of hydrocarbons which otherwise would not be recovered. NOW, THEREFORE, IT IS ORDERED THAT: 1. Union Oil Company of California be permitted to conmLingle production from the referenced pools in the referenced well. DONE at Anchorage, Alaska and dated September 22, 1977. Thos. R. Marshall, Jr., Executive Secretary Alaska Oil and Gas Conservation Conm%ittee Concurrence: O. K. Gilbreth, Jr., fg~airman Alaska Oil and Gas conservation cc~mittee Public Hearing Conservation File No. 147 Tuesday, Aug. ust 23, 1977 9:30 AM Alaska Oil and Gas Conservation Ccra~ittee LIST Name O. K. Gilbreth, Jr. Thos. R. Marshall Gary Carlson Steve Schreiber Hoyle H. Hamilton Larry Varva Representing State DOC/2 State DOGC Union Oil Company Union Oil Company State DOCKS Union Oil Company Location Anchorage Anchorage Anchorage Anchorage Anchorage Anchorage Initials in the transcription following indicate those speakers above. Public Hearing - Conservation File No. 147 Tuesday, August 23, 1977 9:30 AM Alaska Oil and Gas Conservation Committee OKG: This meeting will ccme to order. This m~eting this morning is for a hearing on an application by Union Oil Company for commingling of the Middle Kenai, the Hemlock Oil Pools in the Trading Bay State A-2 and Trading Bay State A-32 well bores. This application has been tabbed as Conservation File No. 147 and the notice of the public hearing was published in the Anchorage Daily News on August 10, 1977, advising of a public hearing to be held here today at 9:30 AM on August 23. For the record, my name is O. K. Gilbreth, Jr., Chairman of the Oil and Gas Conservation Committee. To my right is Thomas R. Marshall, Jr., Chief Petroleum Geologist, Executive Secretary of the Cc~mittee, and to his right, Hoyle H. Hamilton, Chief Petroleum Engineer, member of the Committee. On my left is Lonnie C. Smith, Petroleum Engineer in the Division of Oil and Gas Conservation. Our recorder is Barbara Morgan. Before we get started I might just set out just for the record, the order of procedure. It doesn't look like we have an overflowing audience today so it probably won't amount to much, but before the witnesses present the testimony we will ask that they be sworn, and then should anyone wish to make a presentation of testimony after the applicants we listen to that or any other statements. The Con~ttee then will ask questions upon cc~pletion of this. At the end of the hearing we'll announce how long the record will be open. lm Those are all the opening remarks I have. Is the applicant ready to present their case? Would you please identify yourself for the record and when you get ready to present your witness we'll have Mr. ~rshall swear him in. LV: I'm Larry Varva, representing Union Oil Cc~pany here, and basically I don't plan to present any testimony, however, I will introduce our witnesses. On n~7 left is Steve Schreiber, representing Union Oil Ccmpany, and Gary Carlson, representing Union Oil Company. We're here today basically, I guess basically, to introduce to you Gary_ Carlson who is our ~rt in this particular area. Let me tell you basically a little about Gary backgroundwise. He graduated with a B.S. in petroleum enginering frcm Montana Tech in 1968. He attended graduate school University of Southern California and Montana Tech obtained a M.S. in petroleum engineering in 1971. His experience consists of 8 years of engineering with the majority in reservoir engineering with 2 1/2 years in Alaska. Gary is going to speak for us here with some testimony and then will be available to answer questions and I believe Steve has done the mapwork if there are any .questions regarding locations. C~D ahead Gary. ~T~4: We' 11 go through the swearing operations. Please stand Gar~./ and raise your right hand. In the matter now at hearing do you swear to tell the truth, the whole truth and nothing but the truth, so help you God? testimony in written form and I'd like to pass it out. when I refer to the well diagram. I do. Be seated. Thank you. My. name is Gary Carlson. I was introduced by Larry Varva. I have my. It will be easier 2 GV: I' 11 go into a very brief histo~3 of the Trading Bay Field mainly ,, concerning our problem here and then explain the problem and requ_~ est. The Trading Bay Field has reached the stage of cc~pletion where every. possible means of exploitation should be considered to insure maximum ultimate recovery during the econc~%ic life of the field. It is estimated that approximately 75 percent of the ultimate recovery has been produced to date. The last usable undrilled slot is being employed to drill Trading Bay State A-20 currently in progress. Therefore, it is imperative that careful consideration be given to maximizing the utility and effectiveness of each wellbore. The recent drilling and workover program on the Monopod was designed with the aforementioned goals in mind. .Wells TBS A-13, TBS A-2, TBS A-16, and TBS A-32 were all fracture stimulated in the Hemlock Zone in order to increase the field wide Hemlock Zone productivity and provide sufficient incentive to reinstate the Hemlock waterflood. Also, in each of the four wells, attempts were made to improve the vertical conformance and areal sweep efficiency in the existing waterfloods. Erosion, corrosion and sand problems have increased significantly with increased water production and it has become evident that there is and will be cases where mechanical separation will not be economically feasible, thus re .quiring wells to either be shut-in prematurely or the elimination of one of the zones in a dually completed well. In either case, the ultimate recovery will be decreased. 3 A specific case is the current problem of Trading Bay State A-2, a dual string producer. It is recc~mended that the "D" Zones and the Hemlock Zone be cc~mingled in TBS A-2. It becam~ evident through production testing and logging that the Hemlock and the "D" Zones were not mechanically separated as designed. A plug was set in the long tubing string below suspected holes in the tubing opposite the "D" Sands. The rate changed significantly in both tubing strings, thus indicating that the "D" Zone was being produced frcm both tubing strings. An accurate estimate of the Hemlock Zone contribution to the total well's production was obtained in this manner. It was suspected that sand and gas production from the "D" Sands eroded through the long string. Two prior attempts were made to eliminate the gas entry without success. The ultimate recovery of the field would be reduced through abandonment of a zone or deferred production fr~m one of the zones, if the zones cannot be cc~tningled. There is a diagram of the comple- tion of Trading Bay State on ~e following page. TBS A-32 was ccmpleted with the capability of conm%ingling the "D" and the Hemlock with the ability to test each one separately with the opening and closing of sleeves. The "D" Zones failed to test significant volumes of oil and therefore cc~mingling of intervals. is not critical at this time. w GC: Basically that covers it. Do you have any questions that I can answer? OKG: Mr. Marshall? TRM: Is your completion diagram what is proposed or what is presently installed on the final page here? GC: The one on Trading Bay State A-2 is representative of what is in the hole currently. OKG: Could you give us any depth with regard to your packer and perforation? GC: I'd be going frc~ memory and just estimating, probably Hemlock would be sc~ewhere in the range of 6000 feet, so the packer would be somewhere around 6050 feet. The packer above the "E" sands would be .approximately 5800 feet and the packer above the D pool would be approximately 5200 feet. TRM: Likewise is your cc~pletion diagram on Trading Bay State A-32 a proposed or as is presently in effect? GC: The mechanical setup is as in effect right now, however, when designed we were looking for the con~ningling of the D and the He~lock and the D sands did not test enough oil to justify a completion and currently it is cc~pleted with the C zone producing frcm the short string and Hemlock frcm the long string. TRM: What mechanically would be done on A-32 to effect this commingling? Would you do different downhole work or can you wireline this thing into production con~ngling? GC: You can open a sleeve opposite the D sands in the long string and produce them together. TRM: You can do that with a wireline on them. GC: That' s correct. And I notice an error in the diagram. The short string does not go to the second packer in A-32. 5~ GC: That was the proposed design and I sul~itted it to do it that way but we did not. With "D" sand not testing production we saw no reason to ever produce the "D" sand diesel through the short strings and currently it' ccmpleted with C short strings. OKG: Any more questions Mr. Marshall? TRM: No. OKG: Mr. Hamilton. H}{H: MI. Carlton, could you elaborate a little bit on your fractured stimulation work in the Hemlock zone and also you mentioned 4 wells where you attempted to improve your vertical performance and your sweep efficiency? GC: This fracturing was more or less experimental as far as the Trading · Bay Field went and we fractured Trading Bay State A-2 first and Hemlock was not producing prior to fracture treatment and is averaging between 3 and 4 hundred 'barrels a day of oil now from fracture stimulation. The designs of the fracture treatments were restricted by the amount of equi~t we could get on board the platform. With apparent success in A-2 we fractured A-16 and A-13. Both had been producing from Hemlock prior to this. These are round numbers. A-16 had produced a couple hundred barrels a day in Hemlock just prior to recompleting. Essentially now it is producing be~en 3 and 4 hundred barrels per day. A-13 was pro- ducing approximately 200 barrels a day from the Hemlock and immediately after fracture it increased to about 1200 barrels a day. A-32 was fractured upon completion and it increased prior to this point. We have reperforated it and it doesn't appear to be making any appreciable amount of fluid considering the additional stimulation . . . (cannot hear) . . . reasonable production rate out of it we're now... (cannot hear) 6 GC: During this same workover program and most of the justifications were rather, for this rather large expense was to repair shallow producing . . . (cannot hear) A-2 was completed in the D sands. It had not been cc~pleted before in the D sands. (cannot hear) . . . by 600 barrels a day, thus improving our area sweep efficiency there. A-16 was completed in the C sands shallow string and we were producing a signifi- cant amount of water. We cemented off one of the suspected water entries to hope to inprove our vertical performance in that well, thus making best use of our water injections. A-13 we treated two of the D sands, shallow D sands cc~pletions, we treated two of the D sands with polymer to reduce the water production there, thus improving our vertical performance in that well. A-32 was completed and was perforated and tested in the C and D zones is currently producing a~Droximately 150 barrels a day frcm tt~eC sands. I think that covers it. 'Are there any more questions? HHH: These rates ~hat you obtained after fracturing, have they been on long enough to be called sustained rates? GC: Yes, I believe so and with this increase in production for Hemlock we feel that we can justify, for the engineering work that is currently being done, to justify reinstatement of the water flood, The rates of the wells prior to this time were low and we believed a minor water influx was offsetting us, small withdrawals. But with this increased production our water influx will not keep up with it and we' re hoping that we can justify a reinstatement of the water flood. HH~: Could you review for me once again the wells where you want to commingle the middle Kenai and the Hemlock. What are the rates frcm the Middle Kenai and Hemlock in these two wells? C~: In A-2 the short string interval, or excuse me, the D sands are pro- ducing approxin~tely 600 barrels a day of dry oil, Hemlock approximately 7 350 to 400 barrels a day. H}{H: Is that also low...? GC: Right. This was determined by setting a plug in the long string, having a cGmbined rate for both tubing strings, setting a plug in the long string, thus isolating the Hemlock frc~ the D, the suspected holes and getting the rate on the D sands only, and inferring the difference would be the Hemlock production. HHH: How about the A-327 GC: A-32 as previously requested was to be a D commingle zone but with ,, the D not proving productive we have never opened it up and it's just a Hemlock producer. Currently it's making very little fluid and we' re watching to design additional stimulation treatments. There are no current plans to cc~ingle the D and Hemlock in this well. This has occurred since our request' for cc~ningling. This is the data we've learned in the meantims. H}{H: Your request now just pertains to the A-2. Are you planning any stimulation work for the D also in this well? GC: No, we, in the workover or completion program we did make attempts at stimulating production frcm the D and were unsuccessful. We have no plans for any production right now. HHH: Are all of your wells currently on gas lift? GC: The only one that is not is A-2, the one we' re discussing today. It is flowing now. HHH: Do you plan on producing wells on gas lift down to the economic limit? GC: Presently, that is, economics indicate that that is the proper way to go, however we are considering possibly trying some high volume pumping scme high cut wells late in~ the life, some attempts at engineering design for this have been done in the past. Right now gas lift looks like the most econc~ical way. 8- HHH: If you were allowed to conm%ingle ~ddle Kenai and Hemlock in well A-2 you would still have the capability of shutting off the water entry if it became significant if one or the other... GC: Yes, we could shut off the Hemlock zone, the D zone with the holes being in the long string and production coming frc~ the short string. In order to shut off the D zone we would have to shut in the well. HH~: But you could make periodic tests if you were getting water entry_ to determine which zone it was coming from? GC: That is correct. We can do it either from production logging or setting a plug in the long stream and testing the short string. There is a measure of risk in setting a plug in the long string that it is possible you won't get the plug back. We~ had quite a bit of difficulty in retrieving the plug on initial tests here a month or so ago. HHH: You have the stinger far enough down below you could set the plug and if it stuck you could still perforate above it? GC: Yes, we could cut it off. But once we cut it off, we'll have diffi- culty setting the plug. We' 11 have .to set it up higher. That is correct. And if we set it up higher we've lost this capability of cutting off and there's a possibility we'd get a little sand production and lose the Hemlock permanently without pulling the well. HHH: That's all the questions I have at the present time. OKG: I have 2 or 3 questions. You indicated from the depths of the packers and the approximate intervals that probably have sc~ething in the order of about 800 feet between the D and the Hemlock or the top at least which would lead me to believe there's 400 lb. differential pressures originally. What's your pressure communication problems look like? B GC: The Hemlock, %~ believe, frcm what little pressure history we have of the Hemlock, has leveled off in the range of 2000 psi. OKG: What was saturation pressure in the Hemlock originally? Is it around that? GC: No, it's quite a bit higher, guess around 2900 lbs. The D sands have been under flood for several years now, about 5 years, and from injection profiles we see that the water has not entered the sands proportionately and we feel have somewhat depleted sands and somewhat pressured in the D sands themselves. We have no way of determining these structures indepen- dently but the average pressure in the D sands would be somewhat less than 2000 lbs. but very close so we don't anticipate any problems as far as cross flow between the D and the Hemlock. At least not any more problems that we already have with the D sands now. OKG: With the insulation that has taken place in the past and the diagram _ you've shown, is it going to be possible to deplete the Hemlock by gas lift or are you always going to have several hundred feet of submergence from your lowest gas lift valve? GC: Presently the Hemlock is flowing with the help from the D sands so essentially we are lifting the Hemlock from the holes in the tubing at roughly 5700 feet, so this would be, cut down a little some of that foot interval. We have other wells on the platform with our dual cc~pletions that we're having to lift significantly higher up the hole and it has not posed a problem in the past. A-16 we talked about a few minutes ago is a C Hemlock producer and we're having to lift from the sea and our effi- ciency is scmewhat lower, but due to the mechanics of it we don't have a choice in that case. -10 OKG: You gave us several rates there which resulted frcm your fracturing and I notice several of them there w~re in the order of 200 barrels a day. Is this pretty close to your economic limit? GC: Not presently. I 'm not sure what our average well productivity is out there, but in the floods we have rates averaging from 1200, 200 barrels of oil per day up to in the 1500 barrel a day range. In Hemlock itself would probably be very close to the econc~ic limit in this 200 to 400 barrel a day range but in cc~plete conjunction with the other water floods, the 200 barrels a day is econcmic. The incremental cost of lifting the well is less than that. OKG: If the application is approved, in your opinion, will it result in recovery of additional oil that couldn't otherwise be recovered? GC: That's correct. We feel that we would have a significant increase in areal sweep efficiency by cc~pleting the Hemlock at this point. It would be the highest structural well, and with the installation of flood, should be the final withdrawal point. This would also be the case in the D sands. It is possible that A-2 will be the final withdrawal point in the D sands. OKG: Is this, I'm not familiar with the geology, is it in some limited fault block, or is it for a large portion of the field .you're speaking of being higher structurally? GC: This is in the main fault block, what we call the 2A fault block. This is where both previous floods have been installed in the 2A fault block and Steve Schreiber has a map and we can show you the map right now. 11- TRM: Please raise your right hand, Steve. In the matter now at hearing, do you swear to tell the truth, the whole truth, and nothing but the truth so help you God? SS: I do. TRM: Thank you. OKG: Mr. Schreiber, in my line of questioning I 'm wondering at this stage how significant a problem this is, or if it is something that is going to apply over large areas. Late in the life of the field, is it scmething that we want to lay the groundwork to commingle everything in the future or sc~ething like that? That is why I was asking about the economics in the area and so forth.' I was wondering how serious this problem is. GC: Could I speak on that matter? This is something we have looked at recently. We become more aware of it everytime we pull tubing on a well we're seeing eroded holes in the tubing that we didn't know were occurring. OKG: Is this the result of sand production or corrosion or what? GC: Both. We see scme of them that have been eroded, son~ of them due to corrosion. We have seen holes created by erosion and then filled with scale where you have a pressure drop across them. With this recent group of workovers it became more evident that this was. going to be a serious problem, there are not sufficient shale intervals to separate some of these sands. It would be very difficult in some cases to eliminate an erosion problem without sacrificing reserves. In the well that we dis- cussed, we tried twice to squeeze off the gas. In both cases, after returning to production, after testing squeeze, sufficient pressures, we still had our problem. The problem is most of these wells that are in the intervals that are completed are perforated essentially from top to bottem just leaving the small shale intervals out. Makes it very difficult to work with mechanically. 12- SS: We feel that this is going to be the case in the future as we get closer to the econcmic limit in some of these wells it would be very difficult to justify pulling them to eliminate some of these problems. While scme of the wells are producing at higher rates, in the past we haven't had this problem, we've been able to justify pulling the tubing and repairing them. I believe in the future that's going to be very difficult and in the later stages of depletion. OKG: With our regulations the way they are, the regUlations provide that the first ccmmingling between two pools we have to have a public hearing and after that we can do it administratively. Can you show us what kind of an area we're looking at? SS: I have structure contour maps. On the top is 57-2 sand which is a D zone sand and a structure contour map on the top of the Hemlock formation. Note the locations, A-2 at this point intersects the top of this sand. OKG: Can you describe that point for the record here? SS: Approximately a measured depth of 5800 feet and the A-2 well. The red dot designates the well location of the newly drilled A-32 well as it inter- sects the top of this thing. The area that we're describing is bounded on 2, possibly 3, sides by faults, the West Trading Bay fault, our Northwest One fault, and our Trading Bay fault which is the main accumulation barrier on the east side of the field. The rest is structurally trapped. OKG: Frc~ the map here it would indicate that there are several wells that go through this area. Do most of the wells outside of the A-2 well penetrate both the D and the Hemlock? Or produce in them, I should say. GC: Of the roughly ten wells that penetrate the D sands and were producing from the D sands at one time, approximately half of them went through the Hemlock and were produced frcm the Hemlock. 13- OKG: OK, if this order were approved, then it would open up for administra- tive approval on any other w~lls like this. How many other wells in the area here are equipped in such a manner that you may have something like the diagram you presented? GC: Okay, there are, with the exception of 32, which at this point in time, cc~mingling is not a critical item, there are 2 other wells that are pro- ducing frc~ the D and the Hemlock, the D being the short string and the Hemlock being the long string, those are A-13 and A-8. A-16 is completed in it, but it is a C zone in the short string, Hemlock in the long string. H}~q: My understanding, this, wasn't the rate very low on this new well you are drilling, A-327 GC: That' s correct. HHH: What do you think that's caused from? Is it qualit~v of the reservoir rock in that location? GC: It could very possibly be, low permeability due to the close association with the faulting, close proximity to major faulting. We .haven't reasonably assured ourselves what the problem is. We anticipated much better pro- duction frc~a all zones there. I guess the consensus of Union Oil Company is that we have fault damaged rock. HHH: Originally you discussed this 'program with us. I thought you men- tioned at that time you hoped maybe that would be your last withdrawal point or so. It looks as though now you'll have to have it downstructure some. GC: That's correct. In A-2, completed in the D sands during this recent workover program, early 1977 could easily be the final withdrawal point. And in both the deep flood and if the Hemlock flood is installed, we're going to reinstate it and it should be the final withdrawal point. 14- TRM: Would you explain why this well would be the final withdrawal point, , ,, the A-2 rather than this? This is a well ccmpletion location, is it not? GC: That's the D sands which we were hoping to have a good producing area and after extensive testing we have come to the conclusion the D sands are not productive at that location, probably from the fault damage. TRM: Oh, I see, it's a stratigraphic type of lithological damage there. One question. In your A-2 well in your D zone you mention in your application about gas entry which has been difficult to control, but didn't I also hear you say that this gas entry was acting as a gas of a natural gas lift to produce your Hemlock zones? GC: It has worked out that way with holes eroded in the tubing to where we're lifting the D sands from both strings and it's being lifted by itself and we're presently more efficient in our production because of that but not by design. And we have essentially 7 sands in the D sands that we have had most of our ~lls completed in and we believe one of them is as secondary gas cap and that's contributing the gas currently. TRM: You mentioned the erosion of the gas in the D zone in the tubing and I believe Easy asked questions something like this, but do you believe this is a corrosive agent in the gas, if so it's not known, is it, you don't have hydrogen sulfide or? GC: No, what we believe to be the cause of our holes in our tubing is from erosion from high velocity gas and sand particles and we pulled the well one time to solve this problem and we saw that it was eroded from mechanically and we found sand in the tubing. We repaired it or thought we had and placed it back on production and ran blast joints in there to prolong the life of it and it still carved holes in the .tubing in a relatively short time. 15- OKG: If this applicaton is approved, I understand you to say that you will probably go back in to restart your injection program. GC: Our engineering design is in progress and we feel that there is a very good chance that frcm initial indications of additional recoveries that we will want to start this and probably soon. OKG: That will be in the Hemlock? GC: That' s correct. OKG: How about the D zone? Is it under? GC: It's under flood right now. OKG: You would continue the D zone and hopefully restart the Hemlock? GC: That' s correct. OKG: That's all the ~questions I have. S_~S: I have some handouts of these maps in reduced form for your files. HHH: Where would you locate your additional injectors in the Hemlock if you want to put more water in the wells? GC: We would try to approach the original oil water interface and make a peripheral flood out of it with 1 or probably 2 injectors. Probably in the range of the original bottcm hole location of A-17 and probably down structure from where A-30 is presently located so we would probably have 2 injectors to improve sweep efficiency, even if one injector will match withdrawals. HHH: Would these be recc~pleted wells since you are running short on slots? C~: One would be deepened, one would be redrill if those are the two wells. A-17 is currently idle, and A-30 is approaching the econc~ic limit if it hasn't already reached it. 16- HHH: You have the injection capacity to add additional water to Hemlock with the addition in equipment? GC: That's correct. LCS: I'd like to ask a question, Gary. On A-2, do I understand that the E pool is shut in and you're producing the D through the short string there? GC: That's correct. D pool has been our gas supply %~11. In the past we had several sands open in that pool and to squeeze them off in their entirety would be very difficult, so we 'ye isolated the packers. With the packer, roughly 6050 isolating the E frcm the Hemlock and the packer at 5800 isolated the D fr~n the E. LCS: But both diagrams, the short string doesn't go through the second packer, is that it? GC: Yes, it does on A-2. The original design was set to where two, any cc~bination of 2 zones could be produced frc~ both tubing strings. We could produce either the D or the E from the short and the long or E in the Hemlock from the short and the long. LCS: Okay, then on your testing the long string for the tubing leak in the D, what assurance do you have that you don't have a leak in the E interval? GC: We set the plug below the E so it's possible that we had holes in the tubing between those two factors, you could have an entry of gas from there, but we used a spinner survey to locate the holes and there was no change in the rate between the end of the tubing and where we located the holes to start with and, in addition, the pressures and the rates from the high GOR gas and oil cc~aing from the D do not approach what we were getting out of the E. The E is much lower preSsure and much lower rate. 17- LCS: Okay, fine. That was another question, is what kind of gas volume , you're getting frc~ the D versus the Hemlock. You've mentioned the oil rates, what kind of gas rates are you attributing to each zone? GC: The gas rate changed very little when we set the plug, indicating that Hemlock oil production was very close to solution GOR and the D was producing the majority of the gas and at the time, fr~m m~nory, I don't have the figures in front of me, but the GOR was about 6000, pro- ducing approximately 600 barrels a day, so we're talking about 3500 to 4000 MCF a day frc~ the D. LCS: That's all the questions I have. HHH: I have a couple more. In your application your testimony you men- tioned approximately 75% of the ultimate recoveries probably going to produce to date. Do you have som~ rough idea what the remaining life GC: Again this is dependent upon oil pricing and operating costs. But in cc~ing to this conclusion of roughly three quarters of our production has been produced today, we felt that we would be reaChing the economic limit in its range frc~ 1984 to 1986. HH~: Earlier when the platforms were originally built up here, there was some question that maybe the platform life itself might determine the life of the field. Is there any possibility in this case, or do you see the platform deteriorating in any way that' could shorten the life? GC: That doesn't prove to be a factor now. They've been able to install wear plates and, this is not my field of expertise, but from conversations with people that are involved with this, that if the econc~ics of the times justified it, the platform could be shored up to maintain production. HHH: That's all the questions I have. 18- LCS: Let me ask you Gary, have you had any, I know that Texaco is an affected operator, have you had concurrence frc~n them on this cc~mingling or anything at all frcm the affected operators? GC: As far as I know we have received no ~cation at all frc~ Texaco. They have an interest in two of our wells which are not located in the fault where A-2 is to where anything that we do mechanically to any of the wells in the 2-A fault block would not affect the wells in which they have an interest. LCS: That's all. OKG: That concludes the questions the cc~mittee has. Do you have any final sunm~nry statement you want to say or conclude? GC: Yes, I guess I'd like to add one additional cc~ment and it has to do with your cc~m~_nt earlier of the possibility of this occurring in the future with other zones. We do feel this is going to be the case and there will be times where it will be infeasible econc~ically to try to isolate zones when the wells are approaching their economic level and expensive pulling of them cannot be justified and we feel that this would be a good time to note that this is going to be a problem that could affect the ultimate recovery. OKG: Thank you. Larry? LV: I 'd like to state that any cc~ments made regarding econcmic limits should be construed specifically regarding wells as discussed and not regarding the entire Cook Inlet of production. OKG: I think we would take that in the context of the hearing. OKG: All right, if there are no further cc~ments then... H}{H: Are you going to consider leaving it open or closed? 19- OKG: I was going to ask if there's any objection to leaving the record open for say 2 or 3 days. HHH: I would say that w~uld be a good idea. I would be in favor of it _ in case we have sc~e additional questions. OKG: Is there any objection to leaving the record open through this Friday afternoon the 26th? GC: Union Oil would have no objection. OKG: We will keep the record open then until 4:00 PM on August 26th .., in the event the Committee should have sc~e other questions. With that we will close the hearing then. 20- ,rYERTISING /ORDEr: NOTICE TO PUBLISHER :, INVOICE MUST BE IN TRIPLICATE SHOWING ADVERTISING ORDER NO., CERTIFIED AFFIDAVIT OF PUBLICATION (PART 2 OF THIS FORM) WITH ATTACHED COPY OF ADVERTISE- MENT MUST BE SUBMITTED WITH INVOICE. Divisim of Oil and Gas Cc~serva~ VENDOR NO. 2 PUBLISHER DEPT. NO. DATE OF A.O. A.O. NO. 4Q09 8/10/77 DATES ADVERTISEMENT REQUIRED: ASA~ ,~.L...~'.x ~ / .~ THE MATERIAL ~ETWEEN THE DQUBLE LINES MUST BE PRINTED IN ITS ENTIRETY QN THE DATES SHOWN. BILLING ADDRESS: 3001PorcupineDrive, ~ra~e, Alaska 99501 AFFIDAVIT-OF-PUBLICATION TED STATES OF AMERICA ,TE OF Alaska [ ss ird DIVISION. ORE ME, THE UNDERSIGNED, A NOTARY PUBLIC THIS DAY SONALL. Y APPEARED 'Mary 'L. Russell WHO, ~IG FIRST DULY SWORN, ACCORDING TO LAW, SAYS THAT SHE IS 'THE Legal C,l~.r]~ OF ;LISHED AT . Anchorage IN SAID DIVISION ['rd AND STATE OF. A~aska AND THAT THE /ERTISEMENT, OF WHICH THE ANNEXED IS A TRUE COPY, ~ PUBLISHED IN SAID PUBLICATION ON THE 10thaDAYOF ,~.st .19 7_Z, AND THEREAFTER FOR. no 4SECUTIVE DAYS, THE LAST PUBLICATION APPEARING ON ' 10thDAY OE August 19 77AND THAT THE FE CHARGED THEREON IS NOT IN EXCESS OF THE RATE kRGED PRIVATE INDIVIDUALS. tSCRiBED ANSSWORN TO BEFORE ME $--'---t_~th DAY OF &,,~,,~- 119_~.2, FARY PUBLIC FOR STATE OFA!2Sk2 COMMISSION EXPIRES 'n¢¢¢m'k~ 1-~- I C~I __ 'MINDER- 'ACH INVOICES AND PROOF OF PUBLICATION,, NOTICE OF PUBLIC HEARING STATE OF ALASKA DEPARTMENT OF NATURAL RESOURCES Alaska Oil and Gas Conservation Cc~nittee Conservation File No. 147 Application of Union Oil Company of California for an order allowing the ccnmtingling of production frc~ the Trading Bay Middle Kenai "D" Oil Pool with the production frcm the Trading Bay Hemlock Oil Pools in the well bore of the Trading Bay Unit State Well No. A-2 and Well No. A-32. Notice is hereby given that the Union Oil Ccmpany of California has petitioned the Alaska Oil and Gas Conservation Conmittee for an order allowing cc~mingling of production in the well bore in the referenced wells. Pursuant to Title 11, AAC 22.215, the cc~mittee will hold a hearing on this matter at 3001 Porcupine Drive, Anchorage, Alaska 99501, at 9:30 AM, August 23, 1977. Thcmas R. Marshall, Jr. Executive Secretary Alaska .Oil and Gas Conservation Cc~mittee 3001 Porcupine Drive Anchorage, Alaska 99501 Publish: August 10, 1977 Robert T. Anderson District Land Manager Union Oil and Gas .~vision: Western Region Union Oil CompanyXbT California P.O. Box 6247, Anchorage, Alaska 99502 Telephone: (907) 276-7600 Telex: 90-25188 . July 26 State of Alaska Oil and Gas Conservation Committee 3001 Porcupine Drive Anchorage, Alaska 99504 Attention: Mr. T. R. Marshall, Jr. Executive. Secretary TRADING BAY FIELD State of Alaska Application for Commingling of the Middle Kenai "D" and Hemlock Oil Pools in the Trading Bay State Am2 andTrading BaY State A-'32 Well Bores Gentlemen: Union Oil Company of'California, on behalf of itself as Operator and Marathon Oil Company, hereby requests the waiver 9fR~ule3~Conservation Order 57 providing for the commingling of the Middle Kenai Oil Pools with the Hemlock Pool in the well bores of TBS A-2 and the TBS A-32. %he Trading Bay Field has reached the stage of development where every possible means of exploitation should be considered to insure the Maximum ultimate recovery during the economic life of the field. The recent recomple- tion of TBS A-2 and drilling of TBS A-32 are examples of attempts to do just that. TBS A-2 was recently recompleted in the "D" Pool to insure maximum areal sweep efficiency at the top of the structure, The Hemlock Zone was fracture stimulated in A-2 in an attempt to increase the well's productivity. The Hemlock Zone was fracture stimulated in TBS A-13, TBS A-16 and TBS A-32 this year to increase the zone's total productivity, thus possibly justifying reinstatement of the Hemlock pressure maintenance project. TBS A-32 was drilled to provide the final withdrawal point in the "C", "D" and Hemlock Pools. It is recommended that the "D" and Hemlock Zones be commingled in both TBS A-2 and TBS A-32. Recent testing has indicated that the "D" and Hemlock are currently in communication with e~ch other through holes in ~':~I:: ~ LT'[ V ~! D' JUL 2 ? 1977 Oil a~Id G:,,',,s Co~servati( State of Alaska Oil and Gas Conservation Committee - 2 - July 26, 1977 tubing string in A-2. Two unsuccessful attempts have been made to eliminate the gas entry in the "D" Zone which has caused the tubing erosion. It appears that A-2 would be recompleted as a Hemlock producer with deferred "D" Zone production if the zones cannot be produced together. This would result in a lower "D" Pool ultimate recovery. The "D" and Hemlock Zone reservoir pressures are close enough to each other as to not cause adverse effects due to commingling. The recent well tests provide data to allocate production to each zone. The "D" and Hemlock Pools would also have to be commingled in TBS A-32 to develop all of the Pools from this location, thus maximizing the effectiveness and utility of the well and optimizing the oil recovery. Following the drilling of TBS A-20, there will be no usable undrilled slot on the Monopod. A-32 will be completed with a packer between the "D~ and Hemlock Pools to allow testing separately to accurately allocate the production to each zone° It is believed that the ultimate recovery of the Trading Bay Field will be reduced significantly without the State's permission to commingle the "D" and Hemlock Pools in TBS A-2 and TBS A-32. Texaco, Inc, the only other affected operator, has been supplied a copy of this application. Your favorably consideration of this application is requested. Very truly yours, RTA: j b c c: Texaco, Inc. PROPOSED COMMINGLING OF POOLS TRADING BAY FIELD The Trading Bay Field has reached the stage of depletion where every possible means of exploitation should be considered to insure maximum ultimate recovery during the economic life of the field. It is estimated that approximately 75 percent of the ultimate recovery has been produced to date. The last usable undrilled slot is being employed to drill TBS A-20. Therefore, it is imperative that care- ful consideration be given to maximizing the utility and effectiveness of each wellbore. The recent drilling and workover program on the Monopod was designed with the aforementioned goals in mind. Wells TBS A-13, TBS A-2, TBS A-16, and TBS A-32 were all fracture stimulated in the Hemlock Zone in order to increase the field wide Hemlock Zone productivity and provide sufficient incentive to reinstate the Hemlock waterflood. Also, in each of the four wells, attempts were made to im- prove the vertical conformance and areal sweep efficiency in the existing water- floods. Erosion, corrosion and sand problems have increased significantly with increased water production and it has become evident that there is and will be cases where mechanical separation will not be economically feasible thus requiring wells to Commingling of Pools Trading Bay Field August 23, 1977 either be shut-in prematurely or the elimination of one of the zones in a duallsr completed well. In either case, the ultimate recovery will be decreased. A specific case is the current problem of TBS A-2, a dual string producer. It is recommended that the "D" Zones and the Hemlock Zone be commingled in TBS A-2o It became evident through production testing and logging that the Hemlock and the "D" Zones were not mechanically separated as designed. A plug was set in the long tubing string below suspected holes in the tubing opposite the "D" Sands. The rate changed significantly in both tubing strings, thus indicating that the "D" Zone was being produced from both tubing strings. An accurate estimate of the Hemlock Zone contribution to the total well's production was obtained in this manner. It was suspected that sand and gas production from the "D" Sands eroded through the long string. Two prior attempts were made to elimina~te the gas entry without success. The ultimate recovery of the field would be re- duced through abandonment of a zone or deferred production from one of the zones, if the zones cannot be commingled. TBS A-32 was completed with the capability of commingling the "D" and the Hemlock ~vi'~h the ability to test each one separately with the opening and closing o~' sleeves. The "D" Zones failed to test significant volumes of oil and therefore commingling of intervals is not critical at '[t'~is time. GEC/sk Suspected holes in ~ong String [emlock Pool COMPLETION DIAGRAM - TBS A-2 "D" Pool "E" Ppol Hemlock Pool o. tEMLOCK COMPLETION DIAGRAM - TBS A-32 RI3W TS}4 NOTE' EVIDENCE FOR WEST TRADING BAY NORMAL FAULT IS WET HEMLOCK HIGH TO FIELD O/W'S IN TB.~2 E~ WTB #1 CORRELATIONSDOUBTFUL INW'T'B ~ 32 '33 / A-12 L T~O ~4~S A-6 A-18 F4UL/- T 9 N / / A-19 A-29 1,4- A-17 ~r A-14 A-27 ,," ,, ,/ THIS SAND WAS ENCOUNT~RlrO uNEX~EC:TEOLY WE:T IN TBS A-30 Df~ILLED SUSPECT WATER INJECTICe~ C. HANN~LING FROM OOWNDtP WELLS II -A BLK ORIG O/W -~822(A'Ig) llt-A BLK OTB -5512 (A-4) I-B ~LK WET '5106(A'13) ;0 COMPL THIS SAND I ' "t"i .... 4 TRADING BAY FIELD 1 ' ...... TOP 57-2. SAND. I [... i ~ .l. f.'.iiii£] ~' ........ ~ ~ .... ' .... " o ...... ,.-o o 0 © @ WELL HEAD PLAN ~*, ~, . , ,, u,, ,..,,.,,,= ' - RI3W NOTE EVIDENCE FOR WEST TRADING BAY NORMAL FAULT IS WET HEMLOCK HIGH TO FIELD O/W'S INTB¢2 & WTB#I CORRELATIONS DOUBTFUL IN WTB ~ .32 .33 I I I A-30 ..... A- '/ --' .'" ?MO 84'1h 633° A-21 '/ OIW ', // ,// / // ~-A 8LK o/w APPARENTLY CONCAVE OOWNWARO - FROM - TO -63'~0' (A-10 8, t3) P0$S O/W - 57.52 (A-15) DATUM CODE. $,$, DEPTH/NET VERT, OTBA01L TO BASE t, '500' 'OOO' _ .,'.' I~....~:N~ ~?,~-..:,-~:¥.t / ...... ' !'":' / TRADING BAY FI ELD /, [~i'i,'"'i . L .... STRUCTURE CONTOURS e"; ....... CONGLOMERATE · :. .:. - :::: ,....~-:=::_=::= :.::~_ :::::=:::.-::.~__~,~,~_ : .,, ................. ~ .... :: :. : ........ :.: -=. -:::- :::: :: .1 ¥=