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HomeMy WebLinkAbout1986-08-27 COUNTY SANITATION DISTRICTS OF ORANGE COUNTY, CALIFORNIA �s P.O. BOX 8127, FOUNTAIN VALLEY,CALIFORNIA 02728-8127 qy� WF 10844 ELLIS,FOUNTAIN VALLEY,CALIFORNIA 927D 7018 (714)982-2411 August 20, 1986 NOTICE OF ADJOURNED REGULAR MEETING DISTRICTS NOS, 1, 2, 3, 5, 6, 7, 11, 13 & 14 AUGUST 27, 1986 - 7:00 P.M. 10844 Ellis Avenue Fountain Valley, California �.r Pursuant to adjournment of the regular meeting of August 13, 1986, the Boards of Directors of county Sanitation Districts Nos. 1, 2, 3, 5, 6, 7, 11, 13 and 14 will meet in an adjourned regular meeting at the above hour and date. secretary II BOARDS OF DIRECTORS County Sanitation Districts apr, Offi. B. 8127 of Orange County, California 10844 Ellis Avenue Fountain Valley, Calif., 92708 Telephones: A. Code 774 JOINT BOARDS 962-2411 AGENDA ADJOURNED REGULAR MEETING AUGUST 27, 1986 - 7 :00 P. M. (1) Pledge of Allegiance and Invocation ( 2) Roll call ( 3 ) Briefing by the State Department of Health Services on a draft report entitled "Stringfellow Facility Remedial Investigation/Feasibility Study: Development and Initial Screening of Alternatives" ( 4) Other business and communications, if any ( 5) Consideration of motion to adjourn MANAGER'S AGENDA REPORT Post Offiu Box 9127 County Sanitation Districts 10844 Ellis Avenue of Orange County, California Fountain Volley, Calif., 92708 Tekph"nes: Area Code 714 JOINT BOARDS 96124111 ADJOURNED JOINT MEETING AUGUST 27, 1986 - 7:00 P.M. Briefing by the State Department of Health Services on a draft report entitled "Stringfellow Facility Remedial Investigation easibl ity tudy: Development of Initial Screening of Alternatives." On May 30, 1986 the State Department of Health Services (DOHS) issued a Draft Report entitled "Stringfellow Facility Remedial Investigation/Feasibility Study: Development and Initial Screening of Alternatives". The purpose of the report is: (1) to formulate alternative long-term remedial actions to prevent or minimize migration of contamination from the Stringfellow Hazardous Waste Site; (2) to prevent or minimize the impact of the contaminants which have already migrated from the site; and (3) to screen the alternative remedial actions for technical feasibility environmental/public health impact and cost. The report is termed a "working document" and will be used for discussion at future community meetings involving the DOHS, EPA, and the public. The report represents an intermediate step in the complete long-term feasibility study and review process. The staff prepared a Summary Report on the Stringfellow Long-Term Remedial Plan and reviewed it with the Executive Committee in June. A copy of the summary was provided to each Board member with the agenda material for the regular July Joint Board Meeting. At the July meeting the Directors were polled and August 27, 1986 at 7:00 p.m. was selected for a briefing on the report for the Directors by DOHS representatives. Enclosed is a copy of the Summary Report on the Stringfellow Long-Term Remedial Plan prepared by staff. Any Director that would like a copy of the full report, please contact Blake Anderson, the Districts' Director of Operations at (714) 962-2411, Extension #350. + COUNTY SANITATION DISTRICTS w ORANGE COUNTY. CAUFORNIA +LMa E . S avEMUE June 20, 1986 wuwrux vx,_cr =wEc"wa MMn '27 mu xa.z9lo SUMMARY REPORT STRINGFELLOW LONG-TERM REMEDIAL PLAN The purpose of this report is to update the Directors on the status of the Stringfellow site and provide a preliminary review of the California Department of Health Services (DOHS) recently completed draft report entitled "Stringfellow Facility Remedial Investigation/Feasibility Study: Development and Initial Screening of Alternatives". The report was prepared by their consultant, Science Applications International Corporation, and issued on May 30, 1986. PURPOSE OF OOHS REPORT - DEVELOPMENT AND INITIAL SCREENING OF ALTERNATIVES The purpose of the DOHS report is to formulate broad alternative long-term remedial actions to prevent or minimize the migration of contaminated groundwater from the Stringfellow site, and to prevent or minimize the impact of contaminants which have already migrated from the site. The report screens the alternative remedial actions for technical feasibility, environmental/public health impacts, and environmental suitability. The report is tensed a "working _ document" and will be used for discussion at future community meetings involving the OOHS, EPA, and the public (a meeting in Orange County is planned for this summer). The report represents an intermediate step in the complete long term feasibility process. STRINGFELLOW BACKGROUND The Stringfellow hazardous waste site was operated as a hazardous waste disposal facility from 1956 to 1972. It is located in the middle of a narrow box canyon one-half mile north of Highway 60 in Riverside County near Glen Avon (see Attachment 1). Approximately 34 million gallons of liquid industrial waste from Los Angeles, Orange, and other surrounding counties were deposited at the site. Included in this amount were spent acids, caustics, solvents, pesticides, cyanides, and metal compounds. The site was eventually closed when it became apparent that liquid waste was percolating from the waste pits and into the groundwater and that a down-canyon plume of contaminated groundwater was advancing toward the community of Glen Avon and into the Chino Basin. Mitigation measures began in 1980 with the draining and minor excavation of the open disposal pits and covering them with a clay cap. Also included were concrete diversion channels that intercept surface flows and divert them away from the site. 1 INTERIM REMEDIAL PLAN The Sanitation Districts became involved in the project when the Santa Ana Watershed Project Authority (SAWPA) approached us for authorization to permit contaminated groundwater extracted from the Stringfellow site to be discharged to the Districts' sewerage system after pretreatment to Districts' standards. Conditional permission was granted in late 1984 by the Boards of Directors after having considered the suitability of the project for discharge to the Districts' sewer system. In December 1985, the interim remedial plan was executed when discharge commenced from the treatment plant constructed by the California Department of Health Services and operated by the EPA. Daily analysis of the treated groundwater has shown that the discharge is consistently in full compliance with the stringent limitations of the discharge permit issued by SAWPA as authorized by the Districts. The plant is currently operating at approximately 25,000 to 40,000 gallons per day. The interim permit allows up to 187,000 gallons per day. LONG-TERM REMEDIAL ALTERNATIVES The long term solution to the clean up of the Stringfellow site falls into three broad categories (see Attachment 2). ° The first is the interception of the clean surface water and groundwater prior to its entry into the Stringfellow site. This alternative would prevent the ongoing contamination of groundwater and its movement down-canyon and into the groundwater basin adjacent to the Santa Ana River. ° The second alternative is to excavate all the contaminated soil and waste mixture from the Stringfellow site, and then either treat it on-site and rebury it or remove it to an off-site location. ° The third major alternative is to intercept the contaminated groundwater after it leaves the Stringfellow site, treat it, and provide final disposal to a POTW (presumably our facilities through the SARI line) or by on-site solar evaporation. All of these alternatives have received preliminary evaluation within the DOHS report. Key to their final evaluation is the development of a groundwater model and completion of the final remedial investigation report which is due in late 1986. According to the OOHS report, the following conclusions have been made regarding the three major alternatives: Intercept Clean Water Prior to Entering Site: The first major alternative, the interception of clean water prior to its entrance into the Stringfellow site, appears to be both economically and technically feasible. Wells would be drilled up-canyon from the site and the clean water would be pumped to a creek bed. Its only apparent v 2 _ v limitation is the inability to completely eliminate the problem. That is, even with an interceptor system completely in service, it appears that the migration of contaminated groundwater into the Stringfellow site will continue. This is because full interception of the up-canyon water is not possible. The effect of intercepting the clean groundwater would be to significantly decrease the amount of contaminated groundwater necessary for interception, treatment, and disposal . The report estimates that the existing mid-canyon extraction rate of contaminated groundwater would decrease approximately 50%. Excavate and Treat or Haul Contaminated Soil/Waste: The second major alternative, excavation of the contaminated waste and soil material and either treat it and rebury it or haul it away, does not appear to be feasible according to the consultant. The estimated volume of material necessary for removal is approximately 1 million cubic yards. This is equivalent to a football field 570' deep. The volume itself is significant but other problems also exist. Assuming that the material is removed off-site for ultimate disposal with or without some kind of stabilization step, the likelihood of obtaining local permits and community permission is doubtful . The problem with the McColl Dump is an example of the near impossibility of transferring Superfund waste from one site to another. Excavation followed by on-site treatment and reburial was also considered. The sail would first be treated utilizing incineration or chemical stabilization. Several technologies were examined and all have been judged to be unsuitable because decontamination would not be to a degree which would render the soil non-hazardous. The report does conclude that it is feasible to leave the contaminated material in place if effective dewatering is accomplished. Pretreatment and Disposal to SAWPA/Districts' System or Solar Evaporation: The third major alternative, down-canyon interception of the contaminated groundwater followed by treatment and disposal to a POTW (presumably the SAWPA/Districts' SARI system) or through solar evaporation, is an alternative or a sub-alternative found in all of the recommended alternatives appearing within the OOHS report. In all of the Stringfellow remedial alternatives identified by the consultant in the report, there apparently will exist the need for the interception of down-canyon contaminated groundwater. This is because upstream interception cannot prevent 100% of the water movement onto the site and, even given the feasibility of excavation, significant quantities of contaminated material would be left behind in the hard decomposed granite and in fractures in the bedrock. The 30 year present worth of the various alternatives examined range from S97-334 million. Attachment 3 summarizes five alternatives presented in the report. The report states that these are not meant to be a comprehensive 3 representation of the potential alternatives. These five are simply a combination of the more promising technologies that can be applied to the problem. The report points out that there are literally hundreds of possible combinations of technologies that can be potentially applied to the alternatives. All alternatives identify the long term operation of the treatment plant and all identify disposal of some volume of waste to a POTW (presumably the Santa Ana River Interceptor and ultimately the Districts) and/or to on-site solar evaporation ponds. REMAINING TASKS OF FEASIBILITY STUDY The alternative ultimately recommended may include the use of the SARI line for the long-term disposal of some of the extracted groundwater after having received suitable, treatment. This will be determined after the long-term remedial action plan has been completed. Attachment 4 is the Executive Summary and the Table of Contents of the DOHS report. Directors interested in obtaining a copy of the report can contact Blake Anderson, the Districts' Director of Operations, who will request extra copies from the DOHS. A public meeting is planned this summer to receive comment on the report. Page ES-3 of the Executive Summary outlines the remaining tasks that must be performed to complete the planning process. rr 4 ATTACIIMENT l NOTHERN Stringfellow Site Plan PITAREA .. MID-CANYON • ,l WELL NO. 114 fl '. • ,.SOUTHERN •a _ • • ;"' PIT AREA LOWER CANYON WAMINUe • • • —MID CANYON • LOWER CANYON WELL NO. MW-178 • GLEN AVON • ``�`. PYRITE �= CHANNEL COMMUNITY GLEN AVON WELL NO. FC-211A2 ELEMENTARY SC)IOOL Figure 3-1 . Location of Wells Selected as Representing Average Contaminant Concentrations for Mid-Canyon, Lower Canyon, and Coomouity. Takeo frum Draft Report: Stringfellow Facility Remedial Investigation/Feasibility Study; May 30, 1906; 0011S ATTACHMENT 2 Excavate Contaminated Intercept Clean Water Soil/Waste Mixture _ Extract Contaminated Groundwater _ YplJl... (rwNYYr Surf[[.W W 4461.[rWIrYY M SIu Lmmrlu pr Wru9rnl WYLrI.{ 5.11 WY9rl.l WruY+rnl Da.nyyl.[Irl LrtunJ.Yr Ilrr Wu9rr.l Vl�b Y,II _ MII WEI SYtlr SYLL1 [YlulY1N 1.-Slm 4.ur16r11 r 911rl1$, .. [r1r1Y1N [r(rlYYe Ibw.6nlrrlJ .IiUu.anl.r DI,Jul✓ 1 [.[rtllr Ir ital oil r�WI IUtlr.l a 14f t y DI ul 1 1 f.•hu I SY.Ir e f/•SII. ,�L_ ' �� t � YlrcWr9. S LL4-11�IIY Off-f1U h-SII. Off-fll. K q1Y UIJ—[11 K4 41Ur[tl Wl1°� MIN f.lJ K4 .CIIIIY MNI jILn11Y glm•9. WcrO.d.W WJI fJ1111y Srrrla. WUr � DIIF IS.a 1 1 Y.[r' IYW Sur4°� YrIn11Y11M1 _ IIOW.1 41nIW.{ 114-9 W IrirWa Cnu. r DIuYr9. D4 JI _�c DIIp�.I [..(41.11J 1 Y Ou tw [a.1rlYlr. - Yminllul U. KW at 1 irwMnpr IJ Ix1Yrllir .JIIU DU�uI 9.1MI1r I.If.lttr 4lnctM WII 4Ur11 b. WII 119Y1 Y .eu1rl11Lll.o frlr�Y1J S Yr. IYIYmIIr fY111. Ll.uWIW J 1U.11.. DI. W 4-SIY [Iw 11 Lllllq W Y111r Fii,w-e 2-5. TLeliu)logy C"birtatim Fluxlwrt Taken from @-aft Report: Stringfellow Facility Remedial Investigation/reasibility Study; May 30, 19116; MIS ATTACHMENT 3 STRINGFELLOW SITE LONG TERM REMEDIAL PLAN FIVE REPRESENTATIVE COMBINED ALTERNATIVESI) CAPITAL ANNUAL 30 YEAR COST O&M PRESENT 'NORTH ALTERNATIVE 1 Extract On-Site Contaminated Groundwater wells, tanks, treatment plant, POTW disposal, monitoring S 2,900,000 $ 4,200,000 $ 42,600,000 Extract Downcanyon Contaminated Groundwater Hid-canyon (existing) wells, freeway wells and community wells; either traaNent and POTW disposal or solar evaporation 8,200,GOD 5,700,000 61,900,000 TOTAL $ 11,100,000 $ 9,900,000 $104,500,000 ALTERNATIVE 2 Intercept Clean pater Groundwater interceptor system, recap the site, improve surface water collectors, monitoring S 25,300,000 S 400,000 S 29,400,000 Extract On-Site Contaminated Groundwater Wells, tanks, treatment plant, POTW disposal, monitoring 3,100,000 3,300,000 20,800,000 Extract Ocwncanyon Contaminated Groundwater Mid-canyon (existing) wells, freeway wells and community wells; either treatment and POTW disposal or solar evaporation 26,300,000 2,900,000 46.400.000 TOTAL S 54,700,000 $ 6,600,000 S 96,600,000 ALTERNATIVE 3 Excavate Soil and Intercept Clean pater Groundwater interceptor system, excavate digabte soil, on-site neutralization, reburial, improve surface water collectors,_ monitoring $ 79,000,000 $ 500,000 S 84,200,C00 Extract On-Site Contaminated Groundwater Wells, tanks, treatment plant, POTW disposal, monitoring 3,ID0,000 3,300,000 20,800,000 Extract Oawncanvpn Contaminated Groundwater Hid-canyon (existing) wells, freeway walls and community wells; either treatment and ROTH disposal or solar evaporation 26,300,000 2,900,000 46,400,000 TOTAL $100,400,000 S 6,700,000 $151,400,000 Draft Report: Stringfellow Facility Remedial Investigation/Feasibility Study, ifornia Department of Health Services, May 1986, data from tables 6-2 through 6.6. ATTACHMENT 3 , (CONT'D) .. CAPITAL ANNUAL JO YEAR COST O&M PRESENT 'WORTH ALTERNATIVE 4 Excavate Sail and Intercept Clean Water Groundwater interceptor system, excavate digable soil, omits neutralization, omits incineration, reburial, improved surface water collectors, monitoring $264,000,000 $ 300,000 $266,000,000 Extract On-Site Contaminated Groundwater Wells, tanks, treatment plant, POTW disposal, monitoring 3,IDO,000 3,300,000 20,800,000 Extract Downcenyon Contaminated Groundwater Mid-canyon (existing) wells, freeway walla and community walla; either treatment and POTW disposal or solar evaporation 26,300,000 2.900,000 46,400,000 TOTAL $293,400,000 $ 6,500,000 $334,000,000 ALTERNATIVE 5 Excavate Sail and Intercept Clean Water Groundwater interceptor system, excavate ... digable sail, transport to offsits RCRA location, improve surface water collectors, - monitoring 218,300,000 400,000 222,400,000 Extract On-Site Contaminated Groundwater Wells, tanks, treatment plant, POTW disposal, monitoring 3,100,000 3,300,000 20,800,000 Extract Oowncanyon Contaminated Groundwater Mid-canyon (existing) wells, freeway walls and community wells; either treatment and POTW disposal or solar evaporation 26,300,000 2,900,000 46,400,000 TOTAL $247,700,000 S 6,600,000 $289,600,000 ..r ATTACHMENT 4 MESCUTIVE SUMMARY 1.0 0TRODUCTION The Stringfellow Hazardous Waste Site, located in .Riverside County, California was operated as a hazardous waste disposal facility from 1995 to 1972. About 34 million gallons of liquid industrial wastes were disposed of at the site, including spent acids, caustics, solvents, pesticides, cyanides , and metal compounds. During the course of operation it became apparent that liquid wastes were percolating from the waste pits into the groundwater and contami. nation was detected downgradienc. The site is situated on the southern slopes of the Jurupa Mountains within a box canyon known as Pyrite Canyon. Approximately one mile southwest of the site lies the community of Glen Avon. The original disposal site covers approximately 17 acres and is located at the head of Pyrite Canyon. A contami- ... nacad groundwater plume extends downgradienc throughout Pyrite Canyon with con- taminanc concentrations decreasing with increasing distance from the anginal disposal site. A plume of contaminated water has been located which axtands southerly into Glen Avon, and threatens drinking water wells. During 1981-1982 interim construction was done at the or'_;'iral sita tc reduce pollutant migration, including removal of surface waste, erasion con- crol, capping, and barrier wall construction. In addition, concam:nated groundwater has been routinely extracted downgradient of the Bice from :930 :c present. As an interim measure a mid-canyon treatment planc for craacmer.t a - che extracted groundwacer was placed in operation is December 1995. nary analysis indicates chat these interim sceps have reduced, but not e':Gmi- nated, the migration of pollutants downgradienc from the site. The California Department of Health Services (OHS) , with funding through a cooperative agreement with the U.S. EPA Region LK, contracted with Science Applications International Corporation (SAID) in March 1984 to compre- hensively evaluate the Stringfellow Site, perform a :emedial investigation (R:) ES-1 and conduct a feasibility study (FS) to investigate the extent of contamination and evaluate methods for mitigating the spread of contaminants from rho Size. The RI process at the Stringfellow Site includes investigation of site geology, hydrology, water quality, and air quality. In addition, contaminated groundwater and sails are being sampled and analyzed. The field work in. esti- gation is virtually complete. The do" generated are being used to develop a groundwater model and an RI report, both scheduled for completion in lata 1986. This report is part of the FS process. The FS process evaluates tech- nologies and develops and evaluates specific remedial alternatives which are applicable at the Site. Figure ES-1 shows the steps in the FS process sche- matically. The alternatives are screened and analyzed at several points in the RI/FS process. A "Draft Interim Report on Development and Screening of Reme- dial Technologies and Alternatives-, issued an July 30. 1985, contains informa- cion on the Site configuration, geological and hydrological features of the Pyrite Canyon area, a characterization of environmental impacts associated with the present Site condition, and standards and criteria applicable to potential remedial actions. Information presented in the Interim Report is relevant to this report, and, for the most part, is included here by reference only. Both volumes comprise the Task XI/XII report. The purpose of this repot: is to: 1. Formulate broad alternative remedial actions to: (1) pre- vent or significantly minimize migration of conramination from the Site and (2) prevent or minimize impacts from contaminants which have already migrated from rho Size. 2. Screen the alternative remedial actions for technical feasibility, arvironmental/public health impacts and cost. A subsequent Task XIO report will provide a detailed technical, envi. ronmental, public health, institutional and cost analysis of the remedial alcernatives which survive the screening presented in this report. ES-2 FEASIBILITY STUDY PROCESS CONTRACT TASK VJMBERS Characterize Problem and Identl:- General Resaonse Ae t!ons ULY 1985 81=11 Formulate and Develop REPORT [Alternative Saecifie Technolo iea - Screen Scecifie Techrolo !es TASK 11/12— — Formulate Broad Remedial Action Alternatives Environmental and Public Health Screening THIS DOCUMIT Cest Sc:een!n Eliminate Inaaarooriate Alrernatives � 11, Identify Remaining Remedial STA=S Action Alternatives TASK Treatabillcj 13 1 Studies Detailed Analysis o: Al ternat8�es Technical Institutional Cost Pub llc _nviror�entsl Hoal c4 Analysis Analysis Analysis Analysis Aralvss TASXIL 14 Summary a: Alternatives Evaluation (Draft Seas ib i'_i c� 6C_dv� TASK Concep+I'- Desi 13 TASK Final FeasibilirF Report and Responsiveness Summar, 1 16 Figure 3-1. Schematic Diagram of Feasibili—f Study Process and its Relationship to this Stac-us Report. and the Project Contract Task N"-hers ES-3 2.0 TECHNICAL FEASIBILITY SCREEPLYc OF CANDIDATE RElEDL1L ALTER-`TATIVES Development of remedial alternatives is the process of compiling suit- able technologies into feasible systems to manage and control the source waste material and the migrating contaminant plume at the Stringfellow Site. The process is accomplished in three steps: • First, the treatment and disposal options are defined in very broad corms. Figure ES-2 illustrates the full range of treatment and disposal options which could be employed in solving Stringfellow Site problems. • Second, the specific treatment, mitigation, and disposal technologies are related to the general options in Step One above. • Third, specific remedial alternatives are developed. Treatment and disposal technologies are combined to create remedial alternatives to manage the source material and migrating plume at the Stringfellow Site. Remedial action is required to control and manage four primary types of materials: (1) uncontaminated surface water runoff from surrounding drainage areas; (2) uncontaminated groundwater from areas upgradient of the Site; (3) the contaminated sail/waste mixture; and (4) contaminated groundwacers from beneath the Site and from the downgradient plume. Individual technologies for each of the four primary material types were evaluated, and then selectively combined into potentially suitable technology combinations and alternatives. The results of this screening process are summarized in the following subsections. `Sanagement of Clean Surface later Uncontaminated surface water should continue to be diverted around the Site. Diverting clean surface waters is more effective and less expensive than managing and treating waters which have contacted the contaminated material. Additional run-an and run-off control structures are required, such as new storm drains and improvement of existing drains. The existing cap over the Site is not an adequate seal to prevent surface water percolation into the ES-4 l ( 1 IMcanWluteO Sur Wler NIWW 1 IP. Slrinyf.l loll SIW Onimag. bale I a-Sit. $n Flpun g-t for Disposal detail. of Specific Getu.Y.Wr option& For bnaye- UKenlWluleJSrounJuWrUpyraJiut W(racllu UPpr�Iwt.nfilo .l..or Of the WIn9l.11oa Site I off-Site — olaposal III MlaKp IO 11.fO-r1pI.P.. L HYJSeIWnWl l nc "I'a" R.Utingl Sea figure 1-1 for Dawl, cut Speclfl— c S Water — 4tl.n. for Nawye- W-SIW nl of Wales 1.4 0.-514 olsppw Lon(u1w WY Soils l IW.WaI [o.WnlutJ Soll/Yaat. Nlatur. LKWaW Nm off-Site LrKWWt Illspos.l a J a-sua fn.t OLLpoWI .t O.-Sit. lrulmul OIL SIW See #'lure 3 a tar pispuul pel.11t ma S'c"o' LIP l Iona I., Nanya. ItanbdwleJ 9rumu6", W1. SiteIerlaalmleJ l IlwcPa te) anJ Do.agraJl.nl IPlune) I U dllel 1111 Wla lrin4 Ym DwayaJleat - Irw We.t II lll#MllelI li1Nl'na.J Figure IS-2. Schia'rll.ill U)sgn9n of 11ro;ul Dul !,Als Well amild lie lkilul To Minapp SI-rlogfol lend WaeLlu :1Lltmle: contaminated material on-site. Any remedial action which involves leaving the waste material in-place should include installation of a new multi-layer can . Management of Clean Groundwater Clean groundwaters from upgradienc areas will become contaminated i. they contact the contaminated soil/waste mixture on-sice. It is desirable to intercept this clean groundwater before it contacts the contaminated material. Two apparently feasible technologies for lncercepting clean groundwacers are extraction well barriers and an adit/gallery system. An extraction well bar- rier could consist of an undetermined number of wells arranged in two rings along the periphery of the Site. Wells in the outer ring would extract un- contaminated groundwaters, which would be dischazged to surface drainage (e.g. , Pyrite Creek) or reinjected for groundwater recharge. Wells placed in the inner ring would be used to extract contaminated leachace from 'oeneath the Site. The contaminated leathers, would require further treatment and/or manage- ment. Groundwater pumping operations would need to be controlled to ensure that the slope of the groundwater was always towards the on-eite area, prevent. ing clean groundwater extraction wells from becoming contaminated with leathers. - An adit/gallery system could consist of a tunnel, approximately 6,000 ft in length with an 11 ft diameter, drilled through bedrock around the perim- eter of the Site and at elevations lower than that of the contaminated solid waste materials. Separate drain holes would be drilled into off-site soi'_s to intercept clean groundwacers and into on-site soil/wastes to remove contami. named leachace. Clean groundwaters would be collected and discharged off-site, whereas the contaminated leachace would require further treatment or restricted disposal. This technology is hydrologically feasible. Detailed requirements for a possible extraction well barrier system and/or adi❑/gallery await completion and analysis of on-going water modeling and geological studies. ES-6 Subsurface passive groundwater barriers, slurry walls or grout cur- cains, will not provide an adequate seal to prevent the migration of upgtadiant groundwacers into the contaminated sail/waste mixture. However, the use of such barriers in conjunction with an adic/gallery drainage system is pocan- cially feasible. Additional subsurface field work scheduled for mid 1986 is expected to provide additional data to evaluate interception and extraction of claan groundwater. Management of the Sail/f7asta Mixture It is not passible to excavate all of the on-site contaminated mate- rial using conventional excavation techniques. Following excavation a sigri- ficanc quantity of contamination would be left in the hard decomposed granite (DG) and fractures in the bedrock. She excavatable portions of on-site contami- nated material comprise the alluvium and -digable- DC with an estimacad in- place volume of 908,000 cubic yards. After excavacion the material would expand (fluff up) to approximately 1,180,000 cubic yards. Off-site transport and disposal to a remoce location of over one million cubic yards of excavated contaminated material is nor feasible. It would be virtually impassible to obtain necessary approvals from all the pcli- cical entitles and regulatory agencies involved. In addition, the cost would be very high and, finally, a significant quantity of contaminazion would be left on-site in the hard DO and fractured bedrock. Off-site treatment of the excavated soil/waste mixture would not be feasible because no adequate facility can be idencified. On-site treatment, including neucralizacion, rotary kiln incineration, and/or stabilization, of excavated contaminated material would be technically feasible. However none of chase treatment techniques is expected to decon- taminate on-site soils to a degree which would render them a non-hazardous •wasce. For example, incineration does nor destroy the heavy metals, and stabi- SS-7 lization and neutralization do not destroy either organics or heavy metals, but reduce their mobility to various degrees. Therefore redisposal of created residues must be to a RCRA approved site whether located on-site or off-sice. In-situ treaccenc of contaminated on-sice material is not technically feasible because of the heterogeneous distribution and variation in depth of chemicals ac the Site. Excavation of digable contaminated on-site material and redisposal of the material into newly constructed RCRA approved calls on-sice would be tech- nically feasible. Treatment of excavated soil using neutralization, incinera- tion and/or stabilization prior to redisposal on-sita into RCRA cype cells would also be technically feasible. It is technically feasible cc leave the contaminated on-site material in place if effective dewacering and isolation of the Site is accomplished. All options for management of on-site waste materials will leave in place the existing contamination in the hard OG and fractured bedrock which is _ not digable by normal excavation methods. Therefore, all remedial alternatives will require perpetual operation and maintenance to some degree because a con- taminanc source will remain. .Nanacement of Contaminated Groundwater Broad options for managing contaminated groundwacers include contain- ment, on-size extraction, and extraction downgradienc. Containment of on-site leachace, or ocher contaminated groundwacers, with subterranean barriers wculd not be feasible because of probable leakage problems. The appropriateness of candidate technologies for treating contaminated groundwaters vary depending on the levels of contaminants present. In general, leachace from the on-site area is characterized as heavily contaminated, whereas the mid-canyon groundwacers are moderately contaminated and groundwacers from the lower canyon and commu- nity areas are lightly contaminated. ES-8 Heavily contaminated and moderately contaminated groundwaters from the on-site and mid-canyon areas must be subjected to treatment prior to any form of disposal, except for disposal to a Class Z &CRA approved dispose: site. Treatment of heavily contaminated groundwaters from the on-sit* and mid-canyon arena to meet surface water discharge standards or reinjection criteria is not technically feasible. Thus, this groundwater will require disposal to a ?07'; or- to solar evaporation ponds after treatment. Treatment of lightly contaminated groundwater in the lower canyon and commmmicy area to meac discharge standards for surface discharge or groundwater reinjection would be technically feasible. Disposal of uncr*aced contaminated groundwater from the lower canyon and community areas to a POT; would also be technically feasible. Extraction well barriers are the only methods considered technically feasible to intercept the contaminated groundwater plume downgradient of the Site. The present status of extraction well barriers is: .. • A mid-canyon extraction well barrier is partially in _ place and operating, and is expected to soon be fully in plate and operating. • A new lower canyon extraction wall barrier near Highway 60 is recommended for early implementation. • An additional excaction well barriers) in the community may be recommended later, depending upon the results of a groundwater modeling study jusc underway. The provision of a permanent alternate water supply to residents of Glen Avon currently receiving bottled water funded by the State will be an element of the long-term remedial actions implemented to manage the downgradient groundwater plume. The alternate water supply program is not addressed in this report but will be discussed in the detailed evaluations of institutional and public health factors which will be included in the Task YT7 iS report. ES-9 3.0 ENVIRONNEINTAL AND PUBLIC HEALTH SCREENING Section 3.0 of this report presents a discussion of the methodology employed in environmental and public health screening of proposed remedial alternatives. Routes of exposure, population exposed, and a toxicity and exposure evaluation are presented. Environmental and public health impacts of specific technologies are presented. No remedial technology combinations were eliminated an the basis of environmental and public health screening. 4.0 COST ESTLYATES Section 4.0 of the report presents capital and operation and mainte- nance (0d11) cost estimates for twenty seven individual treatment and disposal technologies under consideration. Table 4-1 (in the text only) summarizes the costs and supporting detail is presented in approximately 50 pages. The indi- vidual treatment and disposal technologies are combined into technically feasi- ble combinations in Section 5.0. The reader may estimace the cost of other cechnology combinations using Section 4.0, if desired. The accuracy of these estimates may vary within a range of 100 percent above to 50 percent below `•� actual costs. 5 .0 COST OF TEMINOLOGY C0-3I:TATIONS Estimated costs for the various technology combinations are presented in this section of the report. A technology combination is an assembly of remedial technologies applied to contaminant pathways and points of exposure in one area, or one media, only. Because of the complexity of the St^ngfellow Site, technology combinations were first cost estimated and analyzed, and -hen assembled into remedial alternatives for costing in Section 6.0 (below) . The cechnology combinations for downgradient groundwater management are cost estimated for two different scenarios: (1) t-he Site is dewatered, and (2) the Site is not dewacered. The average cost for each condition is then used during later analyses. ES-10 Costs for on-site technology combinations are presented for: 1. No Action. 2. On-site Leachata Management Only; (no dewatering) . 3. Dewatering Only; dewater the Site by means of an adic/ gallery system or extraction wells, with recapping and surface drainage improvements. Minimal excavation of contaminated soil is included. 4. Dewatering, Excavation, Treatment by Neutralization, and RCRA Cell Construction; dewater the Site plus excavation of the digable contaminated soil, neutralization of the soil, and redeposition into on-site RCRA type cells. S. Dewatering, Excavation, Treatment by Incineration, and RCRA­ Cell Construction; dawater the Site, with excavation of the digable soil, neutralization and incineration, and radeposition into RCRA type calls. 6. Dewatering, Excavation Plus Disposal to Off-Site RCR4 Site; dawater the Site, with excavation of the digable soil, transport and disposal to an off-site RCRA per- mitted disposal facility. 6.0 REMEDIAL ALTERNATIVE SELECTION In this section remedial alternatives were developed by assembling technology combinations (5.0 above) into feasible systems to manage and control the source waste material and the migrating contaminant plume at the Stt'_ag- fellow Site. Downgradienc extraction well barriers and extracted water management are included in all Stringfellow remedial alternatives regardless of the speci- fic remedial actions implemented in upgradient or on-sice areas. Estimated costs for general remedial alternatives are presented in Table ES-1. In terms of estimated 30 years present worth costs the temedial alternatives range in cost from $97 to $334 million. Initial capital cost for remedial alternatives ranges from $55 to $293 million. ES-11 Table ES•1. Summary of Socal Capital, Annual 0&11, and 30 Year ?resent Worth Costs for General Remedial Alternatives Including Downgradient Extraction and Management Costs ($1,000) 30 Year Capital Annual ?resent Remedial Alternative at the Site Cosa O&M 'Worth (1) Extraction and treatment of 20 gpm from 11,100 9,912 104,526 on-site wells with no dewatering (2) Adit/gallery installation, and recapping 54,750 6,593 96,831 on-sita area (3) On-site soil excavation with on-site 108.480 6,700 151,390 disposal in RCRA-type cells (4) On-site excavation with neutralization, 293,470 6,450 334,024 incineration, and redisposal to an on-site RCRA type call (5) On-site excavation with off-site disposal 247,750 6,593 289,651 ES•12 In the next step of the Feasibility Study (Task Xi7) a deca_:ad. evaluation of each of these remedial alternatives will be made, excec= fo_ -excavation with off-site disposal', which has been eliminated for cional and cost reasons, and -No .Action- which has been eliminated for public health and environmental reasons. �5-13 Table of Concencs Title EXECUTIVE S➢MIARY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . =5-- 1.0 INTRODUCTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . '1 -1 2.0 TECHNICAL FEASIBILITY OF CANDIDATE R=IAL ALTEMIATIVES. . . . . . . . _-: 2.1 Alternative Screening Approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.1.1 Remedial Alternative Technology Combinations. . . . . . . .2-3 2.1.2 Groundwater Treatment Technology Combinations. . . . . . .2.13 2.2 Management of Clean Surface ;;star. . . . . . . . . . . . . . . . . . . . . . . . . .2-LS 2.3 Management of the Clean Groundwater. . . . . . . . . . . . . . . . . . . . . . . .2-19 2.4 Management of the Soi1/Vasta Mixture. . . . . . . . . . . . . . . . . . . . . . . 2-20 2.4.1 Excavation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-20 2.4.2 Leave in Place. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-21 2.4.3 Excavated Soil Treatment Option. . . . . . . . . . . . . . . . . . . . . 2-24 2.5 Management of Contaminated Groundwater and Leachate. . . . . . . .2-25 2.5.1 Extraction or Containment. . . . . . . . . . . . . . . . . . . . . . . . . . .2-23 ... 2.5.2 Treatment or No Treatment. . . . . . . . . . . . . . . . . . . . . . . . . . .2-28 - 2.5.3 Treatment/Disposal Options for Heavily Contaminated Leachate From On-Site and Immediately Below the Barrier Dam. . . . . . . . . . . . . . . . .2-29 2.5.4 Remedial Actions For Moderately Cancaminatad Groundwater Extracted from the Mid-Canvon Area. . . .2-30 2.5.5 Trea®ent/➢isposal Options for Lightly Contaminated Groundwater Extracted from the Lower Canvon and Community Areas. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.3_ 2.5.6 Extraction Vell Barriers Flow Volume. . . . . . . . . . . . . . . .2-32 3.0 ENVIRONME MA.L AND PUBLIC HEALTH EVALUATION. . . . . . . . . . . . . . . . . . . . . . 3-- 3. 1 Background. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.1- 3.2 Chemical Constituents of Concern at the Stringfellow Sire. . 31-2 3.3 Exposure Evaluation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2 3.3.1 Possible Rau-as of Exposure. . . . . . . . . . . . . . . . . . . . . . . . . 3-2 3.3.2 Populations Exposed. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3 v i Table of Contents (conc'd) Title sa a.. 3.4 Toxicity and Exposure Evaluation. . . . . . . . . . . . . . . . . : . . . . . . . . .3 . 3.5 Environmental and Public Health Impacts of Specific Technologies. . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3.7 3.6 Conclusion. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-7 4.0 COST ESTIMATES. . . . . . .. . . . . . .. . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4.1 4.1 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4.1 4.2 Individual Remedial Action Costs. . . . . . . . . . . . . . . . . . . . . . . . . . .4-2 4.2.1 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . : . . . . . . . . .4-2 4.2.2 Cast of the Adit/Gallery System. . . . . . . . . . . . . . . . . . . . .4.7 4.2.3 Cost of Upgradient Extraction Wells to Dewater the On-Site Area. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4.10 4.2.4 Cost of Improved Surface Water Management. . . . . . . . . . .4.10 4.2.5 Cost of Multi-layar Cap System. . . . . . . . . . . . . . . . . . . . . .4.12 4.2.6 Cost of Excavating Digable On-Site Contaminated Soil. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-14 4.2.7 Cost of Transporting and Disposing Excavated Material to an Off-Site Land Disposal Facility. . . .4-15 4.2.8 Cost for Neutralizing Excavated Material. . . . . . . . . . . .4.16 4.2.9 Cost of On-Site Incineration of Excavated Material. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4.16 4.2.10 Cost of Solidification/Fixacion. . . . . . . . . . . . . . . . . . . . .4-18 4.2.11 Cost of Redisposal of Excavated and Treated Material ac an On-Site Facility Meeting RCRA — Standards. . . . tandards. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-19 4.2.12 Cost of Redisposal of Excavated and Treated Material at an On-Site Facility With a Single Liner. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4.20 4.2.13 Cost of a Mid-Canyon Extraction Well Barrier. . . . . . . .4-21 4.2.14 Cost of a Lover Canyon Extraction Well Barrier. . . . . .4.21 4.2.15 Cost of Downgradient Reinjection Wells. . . . . . . . . . . . . .4-23 4.2.16 Cost of Flow Equalization. . . . . . . . . . . . . . . . . . . . . . . . . . .4.24 4.2.17 Cost of Lime Precipitation. . . . . . . . . . . . . . . . . . . . . . . . . .4-25 4.2.18 Cost of Rotating Biological Contactors. . . . . . . . . . . . . .4.26 4.2.19 Cost of Air Stripping. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-28 4.2.20 Cost of Activated Carbon Contact Beds. . . . . . . . . . . . . . .4-29 4.2.21 Cost of Reverse Osmosis. . . . . . . . . . . . . . . . . . . . . . . . . . . . .4.29 4.2.22 Cost of PACT T:! Treatment. . . . . . . . . . . . . . . . . . . . . . . . . . .4-31 4.2.23 Cost for POTW Sewer Line Disposal. . . . . . . . . . . . . ... . . . .4.34 4.2.24 Cost of Soler Evaporation Ponds. . . . . . . . . . . . . . . . . . . . .4.37 4.2.25 Cost of Disposal of Liquids to Off-Site RCRA Permitted Facility. . . . . . . . . . . . . . . . . . . . . . . . . . .4-37 4.2.26 Cost of Discharge of Treated Liquids to Surface Waters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-29 4.2.27 Costs for Monicoring, Sampling, and Analysis. . . . . . . .4-39 ii Table of Contents (conc'd) Title 5.0 COST OF TECHNOLOGY CONBLTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..i. 5.1 Purpose. . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . 5.11 5.2 Required Downgradient Remedial Actions. . . . . . . . . . . . . . . . . . . . . 5-1 5.2.1 Extraction Well Barriers. . . . . . . . . . . . . . . ... . . . .... . . . .5- 5.2.2 Management of Groundwater From the Hid-Carry Extraction Well Barrier. . . . . . . . . . . . . . . . . . . 5.2.3 Management of Groundwater From Lover Canyon and Community Extraction Well Barriers. . . . . . . . . . . .3.6 5.3 On-site Remedial Actions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-10 5.3.1 Management of Heavily Contaminated Leachate Extracted From the Site. . . . . . . . . . . . . . . . . . . . . . . . . . .5-10 5.3.2 Oewacering of the Site. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-15 5.3.3 Management of On-Site Contaminated Soil. . . . . . . . . . . . .5-'_6 6.0 REMEDIAL ALTERNATIVE SELECTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-1 6.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-' 6.2 Development of Remedial Alternatives of Downgradienc Plume Management as a Constant. . . . . . . . . . . . . . . . . . . . . . . . . . .6-1 6.3 Downgradienc Plume Management Options. . . . . . . . . . . . . . . . . . . . . .6.10 6.4 No Action Alternative. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-13 _ 6.5 Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-16 APPENDICES A A Preliminary Estimate of Stringfellow Site Fxcavac'-on Volume. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .a-1 B Community Soils Characterization. . . . . . . . . . . . . . . . . . . . . . . . . . .3-1 C Objectives and Scandards/Criteria for Stringfellow Size Clean-Up. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D Possible Methodology to Determine Soil Contaminant levels to Meet Clean-Up Criteria at the Stringfellow Size. . . . . E Estimated Contaminant Removal Efficiancies of Trea�ent Technologies When Applied to Stringfellow Wastewater Streams. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E•1 F Estimated Air Emissions From Solar Evaoorarion Ponds at Stringfellow. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .F-1 G Bibliography. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G iii - List of Figures v Title ?aae ES-1 Schematic Diagram of Feasibility Study Process and Its Relationship to This Scatus Report, and the Project Contract Task lumbers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ES-3 ES-2 Technology Combination Flowchart. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ES-: 1-1 Schematic Diagram of Feasibility Study Process and Its Relationship to This Status Report, and the Project Contract Task lumbers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5 2.1 Schematic Diagram of Broad General Options Potentially Used to Manage Stringfellow Waste Streams. . . . . . . . . . . . . . . . . . . . . . . . . 2.2 2-2 Specific Options for Management of Uncontaminated Upgradient Groundwater. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.7 2.3 Details of Specific Options for Management of Wastes and Contaminated Soils. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8 2-4 Specific Options for Management of Contaminated Groundwater. . . . 2.9 2.5 Technology Combination Flowchart. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10 2-6 Treatment and Disposal Options for Heavily Contaminated Ground- water From an On-Site Adit System or Extraction Wells. . . . . . . . 2.15 2.7 Treatment and Disposal Options for Moderately Contaminated Groundwater From the Plume in the Mid-Canyon Area. . . . . . . . . . . . 2-16' 2-8 Treatment and Disposal Options for Lightly Contaminated Groundwater From the Plume in the Mid-Canyon Area. . . . . . . . . . . . 2-17 3-1 Location of Wells Selected as Representing Average Contaminant Concenracions for Mid-Canyon, Lower Canyon, and Communi�y. . . . . 3-6 APPENDICES A-1 Approximate Surface Areas of Site Areas Delineated in this Calculation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-: B-1 Location of Soil Sampling, Zones Along'Pyrite Channel. . . . . . . . . . . 3-2 F-1 Effect of Molecular Weight and Environmental Characteristics on Liquid-Phase Exchange Coefficient. . . . . . . . . . . . . . . . . . . . . . . . . . . F-3 F-2 Effecr of Molecular Weight, Wind Speed and Current on Gas-Phase Exchange Coefficient. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F•4 iv List of Figures Title 'as= F-3 Solubility, Vapor Pressure and Henry's Law Constant for Selec_ad Chemicals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7•3 �.r v List of Tables ..r Title ?axe ES-1 Summary of Total Capital, Annual O&A, and 30 Year Present Worth Costs for General Remedial Alternatives Including Downgradienc Extraction and Management. . . . . . . . . . . . . . . . . . . . . . . E5-12 1.1 Sham and Inn$-Term Clean-Up Objectives for Stringfellow. . . . . . . 1.3 2-1 Candidate Remedial Technologies Remaining After Initial Technical Feasibility Screening. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2--. 2-2 Technologies Eliminated from Further Consideration for Use at Stringfellow. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11 2-3 Remedial Action Technology Chart. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.14 2.4 Assumed Flow Volumes from Extraction Well Barriers Under Present Conditions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-33 3.1 Summary of Potential Environmental and Public Health Impacts of Technologies at the Stringfellow Sice. . . . . . . . . . . . . 3-8 4-1 Cost 5ummary of Various Remedial Actions. . . . . . . . . . . . . . . . . . . . . . . 4-3 4.2 Estimated Capital Cost of the Adit/Gallery System. . . . . . . . . . . . . . 4-3 4.3 Estimated 0 S H Cost of the Adit/Gallery System. . . . . . . . . . . . . . . . 4-8 4.4 Assumed Effect of a Sice Dewatering System (Gallery or Extraction Wells) Installation On Future Quantity and Quality of On-Site Ieachate and Downgradient Extracted Groundwater. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3 4-5 Estimate of Capital Costs for Upgradienc Extraction Wells. . . . . . 4-6 Estimate of Annual 0&1 Cost for Upgradient Extraction Wells. . 4-7 Estimated Capital and Annual OM Costs for a Mulzi-lavered CapSystem. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ­13 4.8 Estimated Capital Cost of Neutralization of Excavated .aterial On-SLte. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -17 4.9 Estimated Capital and OM Costs for Operation of Hid-Canyon Extraction Wells. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 4-10 Estimated Capital and 0&1 Costs for the Installation of a Lower Canyon Extraction Wall Bar-ier. . . . . . . . . . . . . . . . . . . . . . . . . +-22 vi List of Tables (cont'd) v Title Page 4-11 Estimated Capital and O6M Costs for the Installation of a Lower Canyon Extraction Well Barrier and Pumping cc the Mid-Canyon. .: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.22 4-12 Estimated Capital and O&M Costs for the Installation of Downgradient Reinjection Galls. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-23 4.13 Estimated Capital Costs for Flow Equalization. . . . . . . . . . . . . . . . . . 4.24 4-14 Estimated Operation and Maintenance Costs for Flow Equalization. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-25 4.15 Estimated Capital Costs for Lime Precipitation. . . . . . . . . . . . . . . . . 4.25 4-16 Estimated Operation and Maintenance Costs for Lima Precipitation. . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . 4.26 4.17 Estimated Capital Costs for Rotating Biological Contactors. . . . . 4.27 4.18 Estimated Odds Costs for Rotating Biological Contactor Treatment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.27 4.19 Estimated Capital Costs for Air Stripping. . . . . . . . . . . . . . . . . . . . . . 4-28 ..r 4-20 Estimated Odds Costs for Air Stripping. . . . . . . . . . . . . . . . . . . . . . . . . . 4-29 4.21 Estimated Capital Costs for Granular Activated Carbon Treatment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . 4-30 4.22 06M Cost Estimate for Granular Activated Carbon Treament. . . . . . 4.30 4-23 Estimated Capital Costs for Reverse Osmosis Treatment. . . . . . . . . . 4-22 4-24 Estimated O&M Costs for Reverse Osmosis. . . . . . . . . . . . . . . . . . . . . . . . 4-32 4-25 Estimated Capital Costs for FACT I.- Treatment System. . . . . . . . . . . . 4.33 4.26 Estimated OSM Costs for PACT Treatment System. . . . . . . . . . . . . . . . 4.33 4-27 Estimated Capital and 06.4 Costs for Disposal to the SAR: Line (From Extraction Well Barrier Area) . . . . . . . . . . . . . . . . . . . . . 4.35 4-28- Estimated Capital and Odell Costs for Disposal cc the SARI Line (From Mid-Canyon Treatment Plant Area) . . . . . . . . . . . . . . . . . . 4.36 4-29 Capital Cost Estimate or Solar Evaporation Ponds. . . . . . . . . . . . . . . 4-38 4.30 OSM Cost Estimate for Solar Evaporation Ponds. . . . . . . . . . . . . . . . . . 4.38 vii `� List of Tables (cone d) Title ?aze 4.31 Estimated Capital and 0&11 Costs for Liquid Disposal to a RCRA Permitted Facility (From Extraction Well Barrier Area) . . . . . . . 4.4C 4-32 Estimated Capital and 0&1 Costs for Liquid Disposal to a RCRA Permitted Facility (From Mid-Canyon Treatment Plant Area) . . . . + 4.33 Estimated Capital Casts for Discharge of Treated Liquids to Surface Waters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . :-42 4.34 Estimated Operation and Maintenance Costs for Discharging Treated Effluent to Surface Waters. . . . . . . . . . . . . . . . . . . . . . . . . . . 4-42 5-1 Extraction Well Barrier Flow Output and Selected Quality Parameters. . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3 5-2 Estimated Casts for Technically Feasible Treatment and Disposal Combinations for 20 gpm of Extracted Groundwater From Mid-Canyon. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-5 5-3 Estimated Costs for Technically Feasible Treatment and Disposal Combinations for 100 gpm of Extracted Groundwater From the Laver Canyon or Community. . . . . . . . . . . . . . . . . . . . .. . . . . . 5.7 5-4 Estimated Costs for Technically Feasible Treatment and Disposal Combinations for Constant 20 gpm of On-Site _ Leachate, Assumes Site is Not Devatered. . . . . . . . . . . . . . . . . . . . . . 5-11 5-5 Estimated Coscs for Technically Feasible Treatment and Disposal Options for On-Sice Leathers Produced by Dewatering the Site. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-_3 5-6 Comparison of Site Devatering Costs by Two Yachods. . . . . . . . . . . . . 5-_5 5-7 Escimaced Costs for Technically Feasible Treatment and Disposal Combinations for Management of On-Site Concaminaced Soils. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . `-. - 5-1 Cost Range of Downgradient Groundwater Nanagemenc Technology Combinations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 6.2 Cost of Typical Remedial Alternative Involving Extraction and Treatment of a Conscanc 20 gpm From On-Site Wells (Na Dewacering) With Downgradient Groundwater Extraction and Management. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.4 6-3 Cost of Typical Remedial Alternative Involving Inscallacion of Adic/Gallerj System, Recapping of On-Sita Area, and Downgradient Groundwater Extraction and Management. . . . . . . . . . . 6-5 viii List of Tables (cont'd) Title ?age 6-4 Cost of Typical Remedial Alternative Involving On-Site Excavation Followed by On-Site RCRA Type Disposal With Downgradient Groundwater Extraction and Management. . . . .. . . . . . 6-6 6-5 Cost of Typical Remedial Alternative Involving On-Site Excavation Followed by Neutralization, Incineration, and Redisposal to an On-Site RCRA Type Facility With Downgradient Groundwater Extraction and Management. . . . . . . . . . . 6-7 6-6 Cost of Typical Remedial Alternative Involving On-Site Excavation, Followed by Off-Site RCRA Site Disposal With Downgradient Groundwater Extraction and Management. . . . . . . . . . . 6-8 6-7 Summary of Total Capital, Annual O&M, and 30 Year Present Worth Costs for General Remedial Alternatives Including Downgradient Extraction and Management. . . . . . . . . . . . . . . . . . . . . . . .6.9 6.8 Cost of Downgradient Portion of Typical Remedial Alternative (Disposal Option 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-11 6-9 Cost of Downgradient Portion of Typical Remedial Alternative (Disposal Option 2) . . . . . . . . . . . . . . . ... . . . . . . . . . . . . 6-12 6-10 Cost of Downgradient Portion of Typical Remedial Alternative (Disposal Option 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-13 6-11 Cost of Downgradient Portion of Typical Remedial ` Alternative (Disposal Option 4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-14 APPENDICES A-1 Estimated Excavation Volumes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-3 A-2 Core Analysis Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-5 A-3 Average Thickness of Units (£t) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-6 3-1 Community Soils Investigation Results. . . . . . . . . . . . . . . . . . . ... . . . . . 3-3 C-1 Clean-Up Objectives for Stringfellow. . . . . . . . . . . . . . . . . . . . . . . . . . . C-2 C-2 Standards and Criteria Applicable to Stringfellow. . . . . . . . . . . . . . C-4 C-3 National and State Ambient Air Quality Standards (April 1985) . . C-11 C-4 Threshold Limits for Discharges in the South Coast Air Quality Management District. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-12 is .s List of Tables (conc'd) Title 'aze D-1 Preliminary Input Values and Restoration Criteria for Stringfellow. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-3 D-2 Estimated Soil Ingestion by Age Group. . . . . . . . . . . . . . . . . . . . . . . . . . C E-1 Stringfellow Site Contaminated Groundwater Quality. . . . . . . . . . . . . E-2 E-2 Estimated Contaminant Removal Efficiencies of Treatment Technologies from Highly Contaminated Groundwater. . . . . . . . . . . . E-3 Estimated Contaminant Removal Efficiencies of Various Treatment Technologies from Moderately Contaminated Groundwater. . . . . . . . E.4 E-4 Contaminant Removal Efficiencies of Various Treatment Technologies from Lightly Contaminated Groundwater. . . . . .. . . . . E-5 E-5 Selected Discharge Quality Requirements for Specific Disposal Opcions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E.7 F-1 Volatilization Parameters for Selected Chemicals . . . . . . . . . . . . . . . F-5 F-2 Volatilization Rates of Pollutants From a Lagoon. . . . . . . . . . . . . . . :.3 F-3 Concentration of Contaminants in Typical Groundvaters from lower Canyon and Mid-Canyon, Plus Streams and A and S Hixture. . . . . . F-4 Method 2: Determination of Air Quality Criteria from OHS Criteria. . . . . . . . . . . . . . . . . . . . . ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-5 Emission Concentrations from Solar Evaporation During I;orst Lase (Radiation Inversion) and Normal ;eather Conditions . . . . . 9 x j '9.h•�+12 9.� 'to �iaeSc+-a �r Qla� 18� baA Ot �r An Overview of the Stringfellow Project Presented to the Hoard of Directors County Sanitation Districts of orange County August 27, 1986 by Ted Rauh Department of Health Services Representatives Ted Rauh, Stringfellow Project Manager Mark Galloway, Stringfellow RI/FS Project Engineer -1- 'r August 27, 1986 FEASIBILITY STUDY PROCESS Identify General Response Actions I Develop and Screen Technologies W Formulate Remedial Action Alternatives Screen (environ., publ. health, cost) Eliminate Identify Feasible Remedial Action Alternatives Current Status I Public Review Detailed Analysis of Alternatives Technical Public Health Institutional Environmental Cost Risk/Reliability Summary of Alternatives Evaluation Public Review/Response Remedial Action Selection Conceptual Design Final Feasibility Report/ Responsiveness Summary Record of Decision 1966-87 Calendar Year Stringfellow RI/FS Schedule August 27, 1986 1986 1967 4 5 6 7 8 9 10 11 12 1 2 3 4 4 5 6 7 8 9 10 11 Stringfellow Adv. Comm. • i Meetings • • , 1. OTC Field Program ` (Upper Canyon) i--- 2. Drill Cuttings Disposal 7. Air Quality Assessment —� i 1 d. Aquifer Tests b,..} ._.d 5. Phase I GW Modeling a. Additional Comm. Wells 1 6. Remedial Investigation (RI)Report 7. Feasibilty Study (FS) Report S. initial Screening Re t_, , , , ~ 9. Treatability Studies ' --r- } i 10. PMd90/ZI/6N/C10dYXC1(9 �Hf 11. Early Imlementation Actions a. Lower Canyon Extraction b. Site Surf. Drains �r 12. Alternative Water Supply r, n � \ A \ S \ 1 1 , [ a r y v z 2 — Co iw ,• II •� m I Ce r a � Q � • JAf•,� 4 W y a W • E �i c. Z a • e i C 3 • Wt � a as o a � 2 Development and Initial Screening of Alternatives Report o Combines technologies into alternative remedial actions. o Screens these actions for technical feasibility, environmental/public impacts and costs. Alternative Action Combinations o Management of upgradient surface and groundwater. o Isolation of on-site wastes by either containment; treatment and containment or removal. o Cleanup of downgradient surface and groundwater. Potential Stringfellow Water Treatment Effluent Volumes Location Gallons Per Minute On-site Leachate 10-20 V Mid-Canyon 20-30 Lower Canyon 35-50 Community 100 + 165-200 MEETING D-lt Mgust 27, 1986 TIME 7:00 p.m. DISTRICTS 1,2,3,5,6,7,11,13 s 14 ( ^" DISIRL:T I JOINT 90ARDS (SALTARE LL1I...XOESTEREY...�� _ (MANDI:)...... ...BAILEY...... (CRANK)........HANSON...... (MURPHY)..... . .. .BEVERAGE...._ (LUXEMBOURGER).GRI SET......�_ (ZIEGLER)... . ... BUCK........ (KIEDER).......STANTON...... (HOBBY)..........CATLIN...... (RISNER).........CLIFT....... DISTRICT 2 (PERRY)..........CULVER...... (SALTARELLI).....EOGAR....... (NORBY)........CATLIN....... I REESE)..........GRIFFIN....:_ (ZIEGLER)......BUCK........}por (LUXEM90URGER)...GRISET...... (LUXEMBOURGER).GRISET....... V_ (CRANK)..........HANSON...... (SILZEL).......KAVANAMI.... (COX)............HART........ (VEDEL)........MAN~......G (SALTARELL1).....MOESTEREY..._ (BEVERAGE).....MURPHY......JG (SILZEL).........KAVANAMI...._ (SCOTT)........NEAL........L (SALTARELLI).....KENNEDT..... _ (CULVER).......PERRY.......L (VEDEL)..........MAHONEY..... (OVERHOLT).....ROTH........ Ll (COX)............MAURER...... (DETER)........SMITH.......JC _ (AGRAN)..........MILLER...... (VIEDER).......STANTON.....}C'_ (BEVERAGE).......MURPHY...... (NELSON).......SOTMN.......AG— (SCOTT)..........NEAL........� (SUTTON).........NELSON...... DISTRICT 3 (LACAYO).........PARTIN...... (CULVER)..... PERRY....... _ (LACAYO).......PARTIN......J� (COX)............PLUMMER..... (NELSON).......POLIS ....... (NELSON).........POLIS....... (MANDIC).......BAILEY....... _ (OVERHOLT).......ROTH........ _ (NORBY)........CATLIN......JC_ (PACE)...........SAPIEN...... _ (RISHER).......CLIFT......._,_ (WILES)..........SIEFEN...... (PERRY)........CULVER......_{� (BEVER)..........SMITH....... (REESE)........GRIFFIN..... (VIEDER).........STANTON..... (LUXEMBOURG .G RIS ET......_ (NELSON).........SUTTON...... ( )........N ...... (MILLER) .......SWAN ...... (SCOTT .......NEAL........jC ( VAGGI).......SYLVIA ( UTON) .....NELSON.......SC_ _ (FINLEY)......... THOMAR...... (OVERHLT).....ROTH ........yi_ (BREEN) . VAHNER...... (PACE).... . SE ........L _ (]OHNiON ........NpXNER...... (WILES)... .. ..SI EFH .....JC (VIEDER).......STANTON......Lc (SELVAGGI).....SYLVIA......_AC— STAFF: DISTRICT 5 SYLVESTER... V I� CLARKE......!/ (COX)..........HART.......... DAWES.........6C (COX).. . .......MAURER....... ANDERSON....JC (VIEDER).......STANTON..... BUTLER......JC BROWN....... V DISTRICT 6 BAKER....... KYLE........ (]OHNSON I....NAHNER......LG VON LANGEN (COX)..........PLUMMER.....jG _ NINSOR......_ (KIEDER).......STANTON.....JC_ STREED......_ CLAWSON.....J� DISTRICT 7 OOTEN....... LINDER......� (SALTARELLI)...EDGAR....... _ DEBLIEUX...._ (AGRAH)........MILLER...... (LUXEMBOURGER).GRISET......�_ (COX)..........MAURER....... (BEYER)........SMITH........ (KIEDER).......STANTON....._K (GREEH)........VANNER....... DISTRI-T Is (MANOI::.......BAILEY...... A� :f:EDER�.......STANTON..... _ IaINLrvi.......THOMAS...... OTHERS: WOODRUFF..... ATKINS...... y_ /� Row• •IIFLBOM`.......�tliTM...... HOHENER..... HOWARD...... :=vEAMJLT).....ROTH........J�—: HUNT.......... ,BE YER)........SMITH.......JC KEITH....... l ' *w— (VIEDER).......STANTON..... � KNOPF.......L/ LE BLANC.... _ 5:3TRi:T 1E LINCH... ..._ V� LYNCH......._ (MILLER).......MILLER...... J PEARCE...... �APPpMvamq (BEYER)........SMITH..NEDY....._j_ YOUNG....... _ (BEYER)........SMITH....... ✓_ YOUNG....... _ - (VIEDER).......STANTON.....y�_ 09!13Y96 ���Vi $RIG. Rel,ulr AILeXA� NEET)NG DA, ATIg115t 27, 1986 TIME 7:00 p.m. DISTRICTS 1,2,3,5,6,7,11,13 a 14 DISTRICT 1 JOINT BOARDS ISALTARELLI)...MOESTEREY... (MANDIC).........BA "Y; .... (CRANK)........HANSON....... — — (MURPHY).........BE VERAG .... (LUXEMBOURGER).GRISET......L (ZIEGLER)........BUCK........ (NIEDER).......STANTON..... 4 (MOREY)..........CATLIN...... (RISHER).........CLIFT....... DISTRICT 2 (PERRY)..........CULVER...... (SALTARELLI).....EDGAR......._ (NORBY)........CATLIN...... REESE)..........GRIFFIN....:_ (ZIEGLER)......BUCK........= _ (LU%EMBOURGER)...GRISET...... (LUKEMBOURGER).GRISET...... W- (CRANK)..........HANSON...... (SILIEL).......KAWANAMI.... (COX)............HART........ (WEDEL)........MANBNET'.l..T (SALTARELLI).....HOESTEREY..._ (BEVERAGE).....MURPHY.M.Z _ (SILIEU.........KAWANAMI...._ (SCOTT)........MEAL........= (SALTARELLI).....KENNEDY..... (CULVER).......PERRY....... (UEDEL)..........MAHONEY..... (OVERHOLT).....ROTH.. (COX)............MAURER...... _ (BEYER)........SMITH.(twv... (AGRAN)..........MILLER...... (WIEDER).......STANTON.....+ (BEVERAGE).......MURPHY..... (NELSON).......4uxzw......?r (SCOTT)..........NEAL........ (SUTTON).........NELSON...... DISTRICT J (LACAYD).........PARTIN...... _ ((LAC AYO).......PRR TIN. ..._ CUL VER).........PERRY.......__ _ CO% ONI.........PLUMMER....._ _ (NELSON)... POLIS (NELS OLIS....... .._V (OVERHOLT).......ROTH........ (NORSY)... ATLIN�p+ + (PACE)...........SAPIEN...... (RISHER)....... .....0 CL IFT. (WILES)..........SIEFEN...... (PERRY)........CULVER...... - (BEYER)..........SMITH....... (REESE)........GRIFFIN.....! (MIEDER).........STANTON..... (LUXEMSOURGER).GRISET...... (NELSON).........SUTTON...... (WEOEL)........ (MILLER).........SWAN........ _ (SCOTT)........N:::::NE At. _ (SELVAGGI).......SYLVIA...... (SUTTON).......NELSON......✓ (FINLEY).........THOMAS...... (OVERHOLT).....ROTH........✓ (GREEN)..........MANNER...... _ (PACE).........SAPIEN...... ✓ (JOHNSON)........MANNER...... (WILES)........SIEFEN......✓ _ (MIEDER).......STANTON yy--. ✓ _ (SELVAGGI).....SYLVIA.i- ..= STAFF: DISTRICT 5 SYLVESTER..._CLARKE...... (CO%)..........HART........ r DAWES....... (COX)..........MAURER...... ANDERSON...._ (RIEDER).......STANTON..... BUTLER...... BROWN....... DISTRICT 6 BAKER....... KYLE........ VON LANGEN MINSOR...... STREED...... CLAWSON..... DOTER....... LINDER...... DEOLIEU%...._ v Dogs led /�avl1 OTHERS: WOODRUFF...._ ATKINS...... nn HOHENER..... U 4 Er _ HOWARD...... HURT........ _ KEITM....... _ KNOPF....... E� LE ..._ LINDSTROM..._ LYNCH. ....._ MARTISO ..._ PEARCE...... l //Tfa r7/ _= WASON......._ YOUNG....... i3rpn U/�e,I Sv"7 - LILI CA August 27, 1986 Adjourned Joint Meeting Notes - 7:00 p.m. SEE ATTACHED SUMMARY REPORT for report of DOHS & EPA. Questions from Directors following DOHS & EPA presentation: Director Ddgar said he was curious re pace of what we are achieving. What number of pounds are involved? What the original volume was compared to what we have taken away. Was answered, don't have any numbers at this time. Should be in remedial study though. we won't be able to document any estimate of how much each element is moving. %s know what we have taken away. Aren't good records of what was put there originally. There were two floods. Are going to do our best to-do what you asked for in remedial investigation. Dort know if we are going to be able to quantify it. Director Catlin asked, how often do you have to recycle if the water doesn't meet standards? Answered, up to now, we have processed about 4 million gallons. Early on there was only one batch that we recycled. This has only happened once. Director PLis asked, will this problem ever be resolved totally or will it be there forever? Answered, don't know whether it is possible to canpletely remove all the contaminants or not. Are attempting to ascertain what we could do. Don't know if we could ever say that. Monitoring will have to go on for a log time. Can develop strategies to protect community. Director Polis commented about receiving bottled drinking water in Glen Avon and asked what they were doing about the swimming pool water? Answered, we are in the process of connecting to Jurupa Community Services District now. Are 400-500 citizens on bottled water now. Are going through construction program V with Jurupa. Reason for going to Jurupa system is based on radiation in water supply not because of Stringfellow. Haven't found contaminants in any of the wells the citizens are using. It is just a protective action. Director Catlin asked, where would you take soils and water to? Answered, it is a problem knowing where to move it to. local citizens in Glen Avon feel the requirement to move it away is not as important to them as being assured that it is treated and contained. Director Stanton stated, sore time back this District was informed that this treatment plant would last 2-3 years. Shortly thereafter it was stated it might last 20 years. were concerned that this situation might last forever. Asked, how many pounds of materials have been removed in the 4 million gallons removed so far? Don't think you really have to have an answer as to how much was dumped in the first place. The number of pounds removed is probably not very significant at all. You are never going to wash it out. If you don't use excavation procedure, will have a permanent process there. Re most economical alternative, what is important to ask is what is the cost per pound of materials removed. If you excavate as much as possible, you are going to have a cheaper cost to remove than if you continue letting clear water wash through and collect at the ed. What is the total cost of material removed?! ! Cost per measure is much cheaper with total excavation. i Answered, could probably com up with a number re how many pounds. Agreed with Stanton. If we evaluate options, that is something we will have to consider. Tfeatmnt plant is to manage groundwater until we complete this study. Were not trying to indicate that flushing contaminants is what we are trying to do. Have to work on soil contamination first and it is going very slowly now. Added that soil washing approach was evaluated but is prohibitively expensive. It was �r eliminated in the beginning. Are getting down to the fine tuning of the containment process. Re digging up contaminants, Glen Avon residents have a good appreciation of the process of removing contaminants from one area to another. We have fast learned that if we take a broader look at hazardous waste, removing it from me area to another is only going to create greater problem in the other area. Don't think that many of these facilities are going to maintain their integrity forever. ERA and the State of California are placing tremendous emphasis on permanent cleanup from a regional perspective. Director asked, where does waste from carbon filter go? Answered, bark to manufacturer for regeneration. Is trucked to Pennsylvania for incineration. Organics can be destroyed. Director Hoesterey asked, are there many sites of contamination downstream? Answered, no, are not finding any evidence in soil samples. Director Hdgar asked, have we seen in 6-8 months of treating the water a change in the concentrations of the treated water? Answered, haven't seen any obvious valid decease. Very difficult. May take years before you see a reduction. Director Stanton commented re excavation, sounds like you are against it. Where can it be taken? What will the problem be like 20-25 years from now if you excavate or leave there? Report should give figures 25 years from now. Director Peer Swan asked, how deep is the aquifer? Where is the barrier and how successful is it? Haw deep are the wells? Answered, sane wells are several hundred feet but don't produce as much as the shallow ones. This is in a box canyon. Peer wondered why the urgency before? Was answered that it was urgent to get the plant built because there wasn't going to be any place to take the water. In fact, the day after the plant was built, there wasn't anyplace to take it anymore. Director Smith asked, are you looking at any other areas in that watershed that are contaminated besides this one? Answered, there is a shall site in the canyon that was reported to have some waste. The State took measures there and it would be dwarfed compared to Stringfellow. Director Hart asked, what are you doing now with waste that is left over? Answered, there are three streams that go out of the plant: (1) treated water goes to OCSD (2) sludge goes to hazardous waste disposal site- Casmalia (3) activate] carbon goes to Pennsylvania. Partin asked, can you Wild a catch basin there? Answered, yes, is in conceptual design now. Asked, are there any financing problem as far as funding? Answered, State and EPA has a Superfund. be are responsible for a 10% share of the ultimate cost of cleanup. Ultimately, we will seek to recover costs from responsible parties. Are in litigation with then now. Citizens in the area have sued responsible parties also and the State. EPA will pay for operation and maintenance for six months to one year. State must show we will have the money to spend for the next 20 years. That money does rat exist at this time. v -2- Asked, who is in charge of cleanup? Answered, State of California. It is a cooperative relationship between the State and ERA. Director Stanton referred to statement in salmon Sumetry Report saying "presumably, the Districts' facilities". Mist happened to the line that goes to o.i L.A. County? Blake Anderson answered, that is our assumption because Orange County is a more likely choice. It is up to their study. DOHS added, we certainly haven't ruled out IA or any other line that might be willing to accept. We haven't dealt with this specific line alternative yet. Should address it later in the report. Joint Chairman Griffin then announced that that will be a public meeting in Orange County relative to this subject. It will be held September 18th at 7:00 p.m. at Mile Square Park Community Center. -3- COUNTY SANITATION DISTRICTS NOS. 1, 22 3, 59 62 72 11, 13 AND 14 OF ORANGE COUNTY, CALIFORNIA MINUTES OF THE ADJOURNED REGULAR MEETING ON AUGUST 27, 1986 - 7:00 P.M. tTATtO& I S'ae� 195e NGE COON` ADMDgISTRA= OFFICES 10844 FT1. AVENUE FOUNTAIN VALLEY, CALIFORNIA ROLL CALL .An adj named regular meeting of the Boards of Directors of County Sanitation Districts Nee. 1, 2, 3, 5, 6, 7, It$ lJ and 14 of Orange County, California, was held on August 27, 1986, at 7:00 p.m., in the Districts' Administrative Office.. Following the Pledge of Allegiance and invocation the roll was called and the Secretary reported a quorum present for Districts gas. 1, 2, 3, 5, 6, 7, ll,,13 and 14 ae follow.: AC[Spe DIRECTORS ALTERNATE DIRECTORS DISTRICT NO. 1: x Ronald B. Hoe.terey, Chairman _Donald J. Saltarelli x Robert Hanson, Chairman pro tam _Oran Creak --a-Dan Driest Robert Luxembourger : Roger Stanton _Rarriect Wieder DISTRICT NO. 2: .Huck Catlin, Chairman _Chris Norby x Richard Buck, Chairman pro tea _George Ziegler e Dan Geiser Robert Luxembourger m Carol Kawavmi _We". Sliest William D. Mahoney x Dorothy Wedel i J. Todd Murphy Michael J. Beverage : Jame. Meet _George Scott : Bob Perry Norm Culver z D. Roth _ a E. Llewellyn Overholt, Jr. x Don Smith Gene Beyer z eo8ex Suntan _Harrlecc Wieder _John R. Sutton .Caney Nelsen DISTRICT NO. 3: z Richard Partin, Chairmen Otto J. Lacayo xRichard Polio, Chairman pro cm _Keith Nelson -7--Ruth Bailey _Robert Mardi., Jr. .Huck Catlin _Chris Morby .Prank Clift _Joyce Risher .Morman Culver _Bob Perry z Dnn Griffin Lester Reese a Dnn Geiser _Robert Luxembourger _William D. Mahoney x Dorothy Wedel -7--Jams Meet _George Scott V .Carrey Nelson _John H. Sutton x Don Roth E. Llewellyn Overholt, Jr. .Sal Sapien _Mike Pace .J.R. "Bob" Siefev Dewey Wiles .Roger Stanton _Harriett Wieder x Charles Sylvia Anthony Selva"i DISTRICT MO. 5: z Evelyn Hart, Chairman _John Cox, Jr. .Philip Hoover, Chairman pro tam Job. Cox, Jr. _:...Roger Stanton Harriett Wieder DISTRICT NO. 6: .Jams Wahnee, Chairman Eric C. Johnson x Ruthelya Plummer, Chairman pro tam John Co., Jr. .Roger Stanton -Harriett Rieder DISTRICT MD. 7: .Richard Edger, Chairman _Donald J. Seltarelli .Sally Anne Hiller, Chairman pro tom _Larry Agean a Dan Grisee Robert Luxembourger z Philip Maurer _John Cox, Jr. x Don Smith _Cane Bayer i Boger Stanton Rarriect Winder x James Wah.ar _Harry Green DISTRICT ND. il: _1.__Ruth Bailey, Chairman _Robert Mandic, Jr. _1.._Roger Stanton, Chairmen pro tea Harriett Wieder a John Threes _Ruth Finley , DISTRICT NO. 13: _John H. Sutton, Chairman x Carrey Nelson x Michael J. Beverage, Chairman pro tem J. Todd Murphy IF-Do. Roth _E. Llewellyn Overholt, Jr. .Don Smith Gene Beyer .Roger Stanton _Harriet Wieder DISTRICT W. 14: x Sally Anne Miller, Chairman _Larry Agran x Peer A. Swan, Chairman pro tm Darryl Miller `/ -:-Ursula Kennedy _Donald J. Seltarelli x D. Smith Gene Bayer n Roger Stanton _Harriett Wieder '2- 08/27/86 STAFF MEMBERS PRESENT: J. Wayne Sylvester, General Manager, Rita Brown, Board Secretary, William N. Clarke, Thomas M. Dawes, Blake Anderson, Bill Butler, Hilary Baker, Corinne Clawson, Judy Bucher, Jim Benzie OTHERS PRESENT: Thomas L. Woodruff, General Counsel, Harvey Hunt, Bill Knopf, Ray Lewis, Ted Rauh, Mark Galloway, Sue Sher, Jerry Clifford, Brian Dllensvang, Sandra Carroll, Robert Shotee ALL DISTRICTS The Joint Chairman introduced Mr. Ted Briefing by the State Department of Rauh of the Department of Health Health Services on a draft report Services (DORS) who then introduced re Stringfellow Facility Remedial other DONS and EPA representatives in Investigation/Feasibility Study: attendance that have been working on the Development and Initial Screening Stringfellow Study: Mark Galloway and Sue Sher from DOHS; Jerry Clifford, Brian Dllenavang, and Sandra Carroll of the Environmental Protection Agency; and Robert Shotee from Science Applications International Corporation. The purpose of the recently completed draft report entitled "Stringfellow Facility Remedial Investigation/Feasibility Study: Development and Initial Screening of Alternatives" is to formulate broad alternative long-term remedial actions to prevent or minimize the migration of contaminated groundwater from the Stringfellow site, and to prevent or minimize the impact of contaminants which have already migrated from the site. The report screens the alternative remedial k.� actions for technical feasibility, environmental/public health impacts, and environmental suitability. The clean-up effort is to protect the underground drinking water basins of the Santa Ana River. The report is a working document and will be used for discussion at future community meetings involving the DOES, EPA and the public. The report represents an intermediate step in the complete long-term feasibility process. Mr. Rauh reviewed the history of the Stringfellow hazardous waste site which was operated as a hazardous waste disposal facility from 1956 to 1972. It is located in the middle of a narrow box canyon one-half mile north of Highway 60 in Riverside County near Glen Avon. Approximately 34 million gallons of liquid industrial waste from Los Angeles, Orange and other surrounding counties were deposited at the site. Mitigation measures began in 1980. EPA looked at interim alternatives for managing the groundwater until a final decision could be made on the ultimate, long-term solution. The interim remedial plan selected was the construction of an on-site pretreatment system to treat the water to Districts' standards prior to discharge into the Districts' sewerage system. Conditional permission was granted in late , 1984 by the Boards of Directors after having considered the suitability of the project. In December 1985 the interim remedial plan was executed when discharge commenced. The pretreatment plant produces three wastestreams: (1) the plant effluent treated to Districts' standards which is discharged to the Districts' facilities via the Santa Ana River Interceptor (SARI); (2) the sludge from the treatment process that is hauled to a Class I dump in Casmalia; and (3) the spent activated carbon in the treatment plant filters that is trucked to Pennsylvania -3- 08/27/86 for regeneration. Daily analyses of the treated groundwater has shown that the discharge is consistently in full compliance with the stringent limitations of the discharge permit issued by the Santa Ana Watershed Project Authority (SAWPA) , as authorized by the Districts. The interim three-year permit allows up to 187,000 gallons per day, however, the plant is currently operating at approximately 25,000 to 40,000 gallons per day and approximately 4,000,000 gallons have been removed since it was started up in December. It is too soon to determine what impact the removal of the contaminated groundwater has had on the overall problem and the DOHS/EPA representatives speculated that it could be some time before a determination could be made. DOHS then reviewed the more apparently feasible long-term remedial alternatives being considered which included: - Interception of the clean surface water and groundwater prior to its entry into the Stringfellow site. (Virtually all of the options include this alternative as an element.) , - Excavation of all the contaminated soil and waste mixture from Stringfellow site, and then either treat it on-site and rebury it or remove it to an off-site location. - Intercept the contaminated groundwater after it leaves the Stringfellow site, treat it, and provide final disposal to a POTW or on on-site solar evaporation. Final evaluation of all of these alternatives is subject to development of a groundwater model and completion of the final remedial report which is due in late 1986. The Directors then entered into a lengthy discussion relative to various alternatives and the important points to be included in the final feasibility study report. In response to questions regarding the volume of waste that had been removed from the site and the remaining volume to be removed, DOHS and EPA representatives stated that they do not have good information on that and it will probably be very difficult to quantify although they are attempting to do so as part of the study. It was also stated that it will be difficult to ascertain over what length of time it will be necessary for clean-up action to take place to remove the contaminants, or if the contaminants can, in fact, be totally removed. However, to a certain degree it will depend upon the remedial alternative selected. Board members pointed out to DOHS and EPA representatives that although the interim remedial solution was to build a treatment plant to pretreat the extracted groundwaters and discharge them to the Districts' sewerage system through the Santa Ana River Interceptor, the study of utilizing this method as a t Long-term alternative should not preclude discharge to a POTW other than the Orange County Sanitation Districts; nor should the alternative of excavating the material and hauling it to another approved site be summarily eliminated because of difficulties encountered at other Superfund sites for this method. Further, in the evaluation of all the various alternatives in the final analysis, considerable weight should be given to the coat per unit-of-measure of clean-up in determining the most economical alternative. .: -4- 08/27/86 In response to a question on funding of the clean-up program for Stringfellow, DONS and EPA representatives explained the program as a cooperative effort between DONS and EPA and reviewed the funding responsibilities of the respective agencies. A public meeting to receive comments on the draft report will be held on September 18,- 1986, at 7:00 p.m. at Mile Square Park Community Center in Fountain Valley. DISTRICT 1 Moved, seconded and duly carried: Adjournment That this meeting of the Board of Directors of County Sanitation District No. 1 be adjourned. The Chairman then declared the meeting so adjourned at 8:35 p.m., August 27, 1986. DISTRICT 2 Moved, seconded and duly carried: Adjournment That this meeting of the Board of Directors of County Sanitation District No. 2 be adjourned. The Chairman then declared the meeting so adjourned at 8:35 p.m. , August 27, 1986. DISTRICT 3 Moved, seconded and duly carried: Adjournment That this meeting of the Board of Directors of County Sanitation District No. 3 be adjourned. The Chairman then declared the meeting so adjourned at 8:35 p.m. , August 27, 1986. DISTRICT 5 Moved, seconded and duly carried: Adjournment That this messing of the Board of Directors of County Sanitation District No. 5 be adjourned. The Chairman then declared the meeting so adjourned at 8:35 p.m. , August 27, 1986. DISTRICT 6 Moved, seconded and duly carried: Adjournment That this meeting of the Board of Directors of County Sanitation District No. 6 be adjourned. The Chairman then declared the meeting so adjourned at 8:35 p.m. , August 27, 1986. DISTRICT 7 Moved, seconded and duly carried: Adjournment That this meeting of the Board of Directors of County Sanitation District No. 7 be adjourned. The Chairman then declared the meeting so adjourned at 8:35 p.m., August 27, 1986. DISTRICT 11 Moved, seconded and duly carried: Adjournment That this meeting of the Board of , Directors of County Sanitation District No. 11 be adjourned. The Chairman then declared the meeting so adjourned at 8:35 p.m., August 27, 1986. DISTRICT 13 Moved, seconded and duly carried: Adjournment That this meeting of the Board of Directors of County Sanitation District No. 13 be adjourned. The Chairman then V declared the meeting so adjourned at 8:35 p.m., August 27, 1986. - -5- 08/27/86 DISTRICT 14 Moved, seconded and duly carried: Adjournment That this meeting of the Board of Directors of County Sanitation District No. 14 be adjourned. The Chairman then declared the meeting so adjourned at 8:35 p.m. , August 27, 1986. e r Secretary, Dire V County Sanitation Districts Nos. 1, 2, 3, 5, 6, 7, 11, 13 and 14 -6-