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82. APPENDIX C COMMITTEE ON DEEP DISPOSAL SUMMARY MINUTES OF MEETING OF SEPTEMBER 1 1, 1955 Called to order at 11:00 a.m. by Dr. M. King Hubbert, Chairman of Committee. ATTENDANCE For full names and affiliations consult List of Participants. Full-time attendance PROCEEDINGS 1. . Part-time attendance Christy Hedrnan RusseD Bass Culler Heroy Seal B down Deacon Hess Thurston Curtiss Ferris Hollow Triplett Fuller Garrels Hubbert Varnes Griggs Gi~uly Joseph Watkins Hunter Gorman ~ Kidney Zumwalt Lieberm~ Hawkins Morgan Piper Renn Dr. Hubbert started the discussion by diagramm~ng two types of geologic structures mentioned ~ previous conferences: A synclinal basin of sedimentary rocks, the lower porous strata contaz~g brine. Sedimentary rocks of uniform, low regional dip, i" which the water might be static or might be in motion, e . g., sedimentary rock sequence of ~ continental shelf. L Discussion of hazards lead to conclusion that safety was to be primary concern, taking precedence over cost. 2. Mr. Ralph Hunter described the geology of that portion of the Michigan Bash with which the Dow Chemical Company is con- cerned. ~ One of He producing horizons contra saturated brine in the center of the basin but the margins near the outcrop area 6

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83. Weld potable waters. Another producing horizon is the Sylvania limestone at a depth of 5,000 feet; 40 feet of the limestone has 10 percent porosity and the remaking 80 feet is very dense. The brom~ne-bear~ng brine is pumped out and waste brie pumped back at a rate-of 350 gallons per minute; it took 30 years for the acti~r- ities at one wed to affect those at another well one and one-quarter miles away. Br~es are also extracted from a deep bed of salt. The salt i-B dissolved by circulating water; after a cavern estimated to be 750 to 800 feet in size is formed, there is a strong likelihood that the roof ~H fracture ant! brined will be drayed in from o~rer- ly~mg beds. 3. Salient pouts of the general discussion. Specific gravity of radioactive wastes ranges from I. ~ to ~ . 3, and the more general types are about I . 20- ~ . 25. (T. ;ndecy} A bed of sedimentary rock having the Kept ~d structural con- figuration deemed acceptable for waste storage is very likely to be below the zone of potable water -- to be fired why brine -- the flow of deep waters (whether potable or salty} is probably very slow - - diffusion is probably slow. AH these characteristics need to be determined before waste is Ejected into a particular horizon. Heat derived from Hsaion ~ the waste cast be dissipated by dilu- tiQU. The vogue of waste is smog enough A that caution rabos ranging from I:l to I,000:l are feasible. The boiling point for Me given solution at the storage depth should not be exceecled so as to avoid fracturing the roof. Hea~g~would be local ~d the rate of brine circulation would be acceferate&, thereby dissipating file heat -- a self-defeating cycles The gentle evolution of vapor would ai80 speed up the tra~- fer of heat. Permeability of a storage bed can be Creased by standard operating procedures of the of] fields, e.g., fracturing and eased Ejection.; -The contact surface between "aquifer" and waste solu- tion can be enormously ~creased, any plugged well-bottoms re- opened Cynthia memo. Pressures used In fracturing are commonly less than that due to the weight of the overburden, so that it seems hardly possible,

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~-1 - 84. mechanically, that the overburden is being lifted. A far more likely result is that vertical or high-age fractures are formed. Might an oil pool have to be sacrificed at some place, some time, to profile a disposal site ? This is mo st ~ ikely if t he disposal Hulas are made more dense than the displaced ground waters. In that case the wastes wad remain in the lowest places, whereat; oil or gas, being lighter than water, are trapped in the high places. Many unproductive structures are known already. In In any fields operators are working on different strata at the same time; it is conceivable that oil might be Other awn from one or more horizons while waste was being injected into deeper hori- zons In the structure e - - I=unch recess - - Meeting reconvened at 2:00 p . m . 4. Pos sidle geologic structural basks ~ the United States . 4. ~ Inspection of "Tectonic Map of the United States" disclosed that there are numerous large basins scatterer] across the country, many of which are known to contain br~ne-bearing strata at depth; some are not sufficiently weU known to be sure of Me nature of the deep waters but they may be fresh- water bearing. Basins of uncertain potability Major br~ne-bearing basing Michigan Basin various Appalachian synclines Northeastern Louisiana Southcentral Oklahoma Illinois Basin various West Texas basins Denver Basin, Colo . Powder Stirrer Basin, Wyo . Bighorn Bask, Wyo . 4 . Z Coastal plain areas offer an alternative method: Introduction of wastes into br~ne-bearing permeable sedimentary forma- tions that dip gently seaward, and pass beneath the continental 5

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t .~ 85 ~ shelf; the contained waters are not static but move slowly dot Hap. The Atlantic Coastal Ply appears generally unfavorable at this time because the known sedimentary section on land is thin, and much potable water is Evolved. ~ the Cape Hatteras region a sequence as much as 10,000 feet thick is known which ~nclucles br~e-bear~ng sancistone formations. The formations of Me shelf slope `;eaward and thicken seaward, and are potentially useful for the clisposition of waste . (De~E;on) .. The Gulf Coastal Plain appears less unfavorable than the Atlantic: here there are tens of thousands of feet of brine- bear~ng `;ediment'; dipping Gulfward. However, in many of Were very high abnormal pres`;ures (as much as 10, 000 feet of anomalous head) prevail. Such wed s are always ~ danger of blowing out. Very careful investigations would therefore be nece';sary in his area. Moreover, the oil fields here, both on land and in the Gulf, are quite closely spaced. 4. 3 The Great Basis Province contend; many potential disposal sites ~ the form of deep gravel-filled topographic basins as well as structural basins in deformed sedimentary rock. The geology of this vast area is so little know, however, that each possible site will have to be investigated extensively. The chances appear high that a renumber of sites cast be found. 4.4 The Columbia Plateau, a section oared 5,000 feet thick of bassets with many porous zones, appears to be an unlikely place to finclauitable disposal sites; ~that area-there is a rapid discharge of enormous quantities of potable water. -5. Salient point`; of the genera] discussion. When the iso-sali~ity lines are parallel to the structural con- tour lines, the brie is static. .. .. .. . I .... ~ . . In west-central Kansas the stupendous quantities of brine from petroleum operations are disposed of by avowing them to OOw (without need of pumping) into "arartite wash" at base of strati- graphic section. The brines are not static but Towing through this

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86. highly permeable layer, and are below any possible productive zone of oil or potable water. A similar "gra~te wash" at Amarillo Ridge is below an potable water ant} Brays northward. It is uncertain whether or not the fresh water farther to the north might be affected if ra- clioactive wastes were introduced into his particular "grate wash" . ''Granite wash" or analogous permeable basal layers may weH exist in grabens of the Great Bash region. 6. Mr. Gorman reminded the group of the immediately urgent prob- lems at the existing AEC installations. It was recognized that the egg ARC Postulations, as weH as the first series of proposed power reactors, present special problems since these seem to have been located without much regard for the waste-disposal problem. ~ each Stance a competent geological renew win have to be macle to finch the least inconvenient waste-disposal site available. In an future taxations the accessibility to a safe disposal site shouic3 be a major consideration ~ determ~g the plant location. The motion was made That waste be disposed of without concern for its recovery, Seconded and pas sed. 8. Mr. John G. Ferris described some conditions obtaining ~ the Michigan Bash ~d elsewhere, and posed severe questions, sum-marizec] as follows: Experience with two, permeable zones between confining beds shows that long-term withdrawal of brine can draw water from confining becis, as evidenced by changes In salinity, hardness, and other data ~ industrial records. In a submarine aquifer the contact between fresh and salt water may be far off shore, as shown by fresh water wells and springs; might radioactive wastes escape to ocean from leaks In the aquifer?

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87. Contact of fresh Id salt water ~ aquifer is ~ ~iyna~nic bal- ance; man captures fresh water-on surface so recharge is im- pened and the contact migrates upward. Ejection of liquid into permeable formation raises pressure. Cracks, faults, unplugged or poorly plugged drill holes (locations in many cases unmowed Louis permit wastes to leak out of for- mation intended for storage and enter formations conta~g valu- able oft or water. Pressure Acreages might induce fracturing any leakage. Deliberate hydro-fractur~g and sanci-fractur~ng might break the coming beds relied on to cont~ the waste. Waste may move out slowly but the pressure wave would move out rapidly: what effect would his have on the contact of fresh and salt water? And con exacting industrial and domestic users? To measure, minimize, arch possibly control Me prea sure effects, the brine to be used as Fluent could be pumped from the same formation the waste is to be Ejected ~to; the "diluent weUs" conic be spaced arour,& the 'injection weld' so as to create a closed system. 9. Crossbed leakage might be monitored any controlled by rings of weHs around injection well. {HoHand) . 10. If the waste solutions are heavy, the leaks win be downward, out of en~nronrnent; using basins means that the disposal of waste wouicI not be taking place ~ structures of present or potential in- terest for petroleum; enormous banks are available ant! small ones will suffice. Waste solutions could be made light for seques- tering ~ anticlines but there are important objections: leaks would be upward, toward the biologic environment, and toward zones of potable water alla possible oil; anticlines are generally small; the of' industry already occupier a great number of anticlines making for competition with disposal ~nsta~ations, an added difficulty for ARC which is unnecessary ~ New of the abundance of basins. . (Hubbert) After Generous attempts to formulate basic principles ~d recom- mendations of policy, the motion was made, seconded, and passed, . . . ~ . .

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88. . . - .~ ... .. A. ...' that a small group make the formulation and present it to the Committee for discussion.~d action. Messrs. -I. B. Heroy, D. J. Varnes, arch H. D. Hogans! were appointed the Subcommit- tee on Resolutions. See item 14. 12. In order to obtain a clearer idea of the magnitude of the waste- disposal problem, the following calculation was made: Suppo se that beginning ~ 1 960, nuclear paws r were produced at a rate equal to the present entire power output of the Unitec~ States, and the waste products, diluted to the extent of 50 gallons of water per gram of fission products, were injected underground into a sancistone 100 feet thick, having 20 percent porosity, what would be the area of the sane! that would be fillet! with waste prod- ucts by the year 2000? At the meeting an approximate calculation was made, and the following are the slightly reprised results: the present power output of the United States is about 4.8 x lOlikw- hr/yr (108 kw at a load factor of 0.54~. The quantity of U-235 required would be 84 metric tons per year, ~d We diluted wastes would amount to 100 million (42-gal} barrels per year. By the year 2000 the area occupied by the wastes would be 40 square miles, or a square of 6.3 miles to the side -- the size of a large oil fielci. For comparison, in the East Texas oil field, 100 million barrels of water per year are currently being Ejected through 58 welts with 7-~ch casings. Eight wells take over 10,000 bar- rels per day each without pumping. Since structural basins this size ~ or much larger are abun- dant, it is conclucled that the creep underground disposal of wastes for a long time to come would Evolve operations which are small as compared with those of the petroleum ~nclustrye 3 . Salient pouts of the general discus sign. If the waste solution were to interact with either the rock c ons ticket s o r the contains ~ b rme a, p r e cipitate s might fo rm which would clog the pores of the reservoir rock. Compatibility of the waste with the rock and water wouic! have to be determined in advances it win be necessary to treat the waste so it win be compatible .

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89. The possibility should be considered that some or aH of the fission products; may tend to be-captured by the clays and other mineral components of the reservoir rock near the wed bore and hence create ar, undesirable local "hot-~;pot." This contingency needs prior investigation in order that it may be avoided. The total volume of waste, at ten-fold dilution, produced by a 100,000 megawatt power economy (as';urning 5 gal/gmU235) is IT or less of the Dual extraction of petroleum in the United States . Most of the fission heat is generated in the first 100 days to one year, and tank cooling is feasible. Strontium ~d cesium produce 99 of the heat, and the calculations ~ item 12 allow for Sr and Cs so the figures are realistic and conservative. Strontium and cesiu$n can be removed from the waste, concen- trated to small volume, ~d given special handing and storage, if necessary, such as sequestering za a deep, dry mine. There unaoubte~y wiO be problems ~ designing the Ejection wed equipment but there is no reason to fear that they wan be beyond the realm of established engineering sciences. (GiDuly) Dyer recess Meeting reconvened at 8: ~ 5 p. m. 14. Mr. Heroy reacithe formulation of the Subcommittee on Resolu- tions; after discussion and modification, the motion was made, seconded, and pas sea that the formulation be adopted as the con- clusions and recommendations of his Committee, as follows: . - The committee has accepted as premises the following: A. That the nuclear waste, if stored undergrounci, shout} be isolated as permanently as possible from contact Offs ring organisms; B. That the nuclear waste may be stored under conditions where it need not be recovered; C. That the disposal of waste is a special problem for each particular installation. 6

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; - ~ ; 90. It is conclude" that these general principles should guide the selection of methods of disposal: I. That the liquids containing the nuclear waste, shall have a greater specific gravity when introduced into the res- ervoir titan the liquids air eady present in the reservoir; 2. That the liquids shad be stored uncergrouna preferably where Obey will remai" under essentially static conditions; 3. That the introduction of the flu~cis Etch the bottom of struc- tural basins is one means of satisfying effectively this condition; 4. That adequate monitoring of the distribution of nuclear waste we r the reservoir be provided by appropriate Observation weHs, which could Moo serve as sources of giluent; 5. That, prior to the introduction of nuclear waste liquids into the reservoir, the problems of heat dissipation, clogging of reservoir space, and chemical reaction tenth the reservoir rock and nabs be evaluated.