SDM S DocI D 00022206 1 . 5 . S



### EXPLANATIO N O F SIGNIFICAN TDIFFERENCE S



### FO R TH E NORWOO D PC B SUPERFUN D SIT E NORWOOD , MASSACHUSETT S

February 200 5

U.S . Environmenta l Protectio n Agenc y Regio n 1 - NewEnglan d Boston , M A

### Norwoo d PC B Superfim d Sit e Explanatio n o fSignifican t Difference s

Februar y200 5 Tabl e o fContent s

I . Introduction......................................................................................... . 1 II . Summar

yo f Sit e History , Contaminatio n Problems , an d Selecte d Remedy......... 3 III . Basi s fo rESD....................................................................................... . 1 1 IV . Descriptio n o fSignifican t Differences........................................................ . 1 2 V . Supportin g Agenc yComments................................................................ . 1 3 VI . Statutor

yDeterminations........................................................................ . 1 3 VII . Publi cParticipation.............................................................................. . 1 4 VIII . Declaration......................................................................................... . 1 4 Table s Tabl e 1 - Revise d Groundwate rCleanu p Standard s Tabl e 2 - Compariso n o fGroundwate rStandard s fro m 198 9 RO D an d ne wRBAL s Appendice s Appendi xA- Applicabl e o rRelevan t an d Appropriat e Requirement s (ARARs ) Table s Appendi xB - MADE P Concurrenc e Lette r Appendi xC - Administrativ e Recor d Inde xfo rth e Explanatio n o fSignifican t Difference sI . INTRODUCTIO N



### A . Sit e Nam e an d Locatio n Sit e Name : Norwoo d PC B Superfun d Sit e (Site ) Sit e Location : Norwood , Norfol k County , Massachusett s B . Lea d an d Support Agencie s Lea d Agency : Unite d State s Environmenta l Protectio n Agenc y(ERA ) Suppor t Agency : Massachusett s Departmen t o f Environmenta l Protectio n (MADEP ) C . Lega l Authority Unde rSectio n 117(c) o f th e Comprehensiv e Environmenta l Response , Compensation , an d Liabilit

yAc t (CERCLA) , 4 2 U.S.C . § 961 7 (c) , Sectio n 300.435(c) o f th e Nationa l ContingencyPla n (NCP) , 4 0 C.F.R . § 300.435(c)(2)(l) , an d Offic e o f Soli d Wast e an d EmergencyRespons e (OSWER ) Directiv e 9355.3-02 , i f EP Adetermine s tha t difference s i n th e remedia l actio n significantl ychang e bu t d o not fundamentall yalte rth e 

### remed yselecte d i n th e Record o fDecisio n (ROD ) wit h respect t o scope , performance , o rcost , EP Ashal l publis h a n Explanatio n o fSignifican t Difference s (ESD) . Th e ES D shal l explai n th e difference s betwee n th e remedia l actio n bein g undertake n an d th e remedia l actio n se t fort h i n th e RO D an d RO D Amendment , an d th e reason s suc h 

### change s ar e bein g made . D . Summary o fCircumstance s Necessitatin g thi s Explanatio n o f Significan t Difference s Th e 198 9 RO D an d th e 199 6 RO D Amendmen t fo rth e Sit e specifya remed ytha t addresse s groundwater , soil , sediment , an d buildin g materia l contamination . I n accordanc e wit h th e 198 9 ROD , EP Acomplete d th e constructio n o f a 6,000-squar e foo t groundwate rtreatmen t plan t a t th e northeaster n edg e o f th e Sit e i n Novembe r1995 . Th e plan t operate d fro m Marc h 199 6 throug h Jun e 200 0 an d remove d approximatel y 26 2 pound s o f groundwate rcontaminants . Groundwate rclean-u p level s wer e originall y base d o n drinkin g wate rcriteria . I n accordanc e wit h EPA' s 199 6 Fina l Groun d Wate rUs e an d Valu e Determinatio n Guidance , i n Ma y2001 , MADE P recommende d a "lo wus e an d value " determinatio n fo r th e groundwate ra t an d i n th e vicinit yo fth e Site . Th e determinatio n wa s mad e base d o n th e aquifer' s classificatio n a s a low-yield , non-potentia l drinkin g wate rsourc e are a a s wel l a s th e fac t tha t nearb yresidentia l o rcommercia l propertie s are supplie d b ypublic , municipa l drinkin g wate rsources . A s a resul t o f MADEP' s "lowus e an d value " determination , ne wcontaminan t exposur e pathway s wer e evaluate d base d o n curren t an d potentia l futur e us e an d revise d 

### -2 -exposur e assumptions . Accordingly , supplementa l ris k assessmen t activitie s wer e initiate d i n 200 1 an d were complete d i n 2004 . As th e resul t of thes e ris k assessments , revise d groundwate rclean-u p levels , hereafte rreferre d t o a s risk-base d actio n level s 

### (RBALs) , wer e calculate d fo rth e Sit e groundwate ri n Marc h 2003 . ERA , b yissuin g thi s ESD , ha s determine d tha t thes e RBAL s wil l becom e th e ne wgroundwate rclean-u p level s fo rthi s Site . Thi s ES D wil l als o documen t mino rchange s t o th e soil , sediment , an d buildin g materia l component s o f th e remed ytha t deviate d fro m th e 199 6 RO D Amendment . E . Availabilit y ofDocument s Thi s ES D an d supportin g documentatio n shal l becom e par t o f th e Administrativ e Recor d fo rth e Site . A n inde xo f informatio n bein g adde d t o th e Administrativ e Record fo rthi s ES D i s attache d a s Appendi xC . Th e ful l Administrativ e Record , includin g it s index , i s availabl e t o th e publi ca t th e followin g location s an d mayb e reviewe d a t th e time s listed : U.S . Environmenta l Protectio n Agenc y Record s Cente r 

### On e Congres s Stree t Boston , M A0211 4 

### (617)918-144 0 Mondaythroug h Friday9:0 0 a.m . t o 5:0 0 p.m . Morril l Memoria l Librar

y 3 3 Walpol e Stree t Norwood , M A0206 2 

### (781)769-020 0 Mondaythroug h Thursda y9:0 0 a.m . t o 9:0 0 p.m . Frida y10:0 0 a.m . t o 5:0 0 p.m . Saturda y9:0 0 a.m . t o 5:0 0 p.m . Sunda y1:0 0 p.m . t o 5:0 0 p.m . II . SUMMAR YO F SIT E HISTORY . CONTAMINATIO N PROBLEMS . AN D SELECTE D REMED Y A . Sit e History an d Contaminatio n Problem s Th e Sit e i s comprise d o f approximatel y2 6 acre s o f mainl ycommercia l an d industria l propert yan d i s bordere d b yRout e 1 an d th e Dea n Stree t acces s roa d t o th e east ; residentia l area s t o th e nort h (acros s Meado wBrook ) an d wes t (adjacen t t o Pellan a Road) ; an d Dea n Stree t t o th e south . Th e Sit e consist s o f severa l parcel s o f land , includin g th e forme rGran t Gea rfacility ; KerryPlace ; an d portion s o f Meado wBrook . I n 1979 , th e Sit e wa s subdivided . Th e northeaster n portio n o f th e Site , approximatel y9 acres , wa s purchase d b yGran t Gea rRealt yTrus t an d lease d t o Gran t Gea rWorks , Inc . Th e souther n an d wester n portion s o f th e Sit e wer e furthe rsubdivided , a majo rportio n -3 -o fwhic h wa s name d Kerr yPlac e an d no wi s comprise d o fcommercia l an d ligh t industria l buildings . Beginnin g i n th e 1940s , previou s owner s o roperator s o f th e Gran t Gea rfacilit yuse d polychlorinate d biphenyl s (PCBs ) i n th e productio n o f electrica l 

### transformer s an d othe relectrica l components . Man yo fthes e operation s resulte d i n th e contaminatio n o f sit e soil , groundwater , buildin g surfaces , an d Meado wBroo k 

### sediments . Groundwate rwa s contaminate d wit h PCBs , volatil e organi ccompound s (VOCs ) suc h a s trichloroethylen e (u p t o 1,70 0 ppb ) an d viny l chloride , an d semivolatil e organi c compound s (SVOCs) . Soi l an d sediment s wer e contaminate d wit h PCB s (u p t o 26,00 0 ppm) , polycycli caromati chydrocarbon s (PAHs) , an d heavymetals . I n 1983 , afte rMADE P detecte d hig h level s o f PCB s i n th e soi l o n th e Site , EP A conducte d a n EmergencyRemova l Actio n whic h resulte d i n th e remova l o fove r50 0 ton s o f highl ycontaminate d soil . I n 1986 , MADE P installe d a 4-foo t hig h wir e mes h 

### fenc e aroun d a 1.5-acr e portio n o fth e Sit e an d constructe d a protectiv e line rmad e o f grave l an d fabri cbehin d th e Gran t Gea rbuildin g t o limi t acces s t o remainin g area s wit h significan t concentratio n o f PCB s i n surfac e soils . EP Aplace d th e Sit e o n th e Nationa l Prioritie s Lis t i n 1986 , makin g th e Sit e eligibl e fo r Superfun d clean-u p funds . EP Asubsequentl ycomplete d th e Remedia l Investigatio n an d Feasibilit

yStud y(RI/FS ) an d selecte d th e remed yi n a 198 9 ROD . Th e selecte d remed yinclude d th e excavatio n an d subsequen t treatmen t o f soils/sediment s b ysolven t extraction ; decontaminatio n o f th e Gran t Gea rbuilding ; an d th e constructio n an d 

### operatio n o fa groundwate rtreatmen t system . Th e Groun d Wate rTreatmen t Plan t (GWTP ) bega n operatin g i n 1996 . Du e t o highe rtha n anticipate d solven t extractio n cos t 

### estimates , logistica l problem s associate d wit h inadequat e spac e t o locat e thi s system , an d base d o n th e likel yreus e o f thi s propert yfo rcommercia l o rindustria l use , EP A change d th e selecte d remed yi n a Ma y199 6 RO D Amendment . Th e RO D Amendmen t calle d fo rth e demolitio n o f th e Gran t Gea rbuildin g an d th e excavatio n an d consolidatio n o fcontaminate d soils/sediment s unde ra n asphal t ca p an d grave l cove rareas . EP A als o agree d t o restor e portion s o fMeado wBroo k excavate d a s part o fth e remedy , t o specification s determine d b yth e Tow n o fNorwoo d a s part o fthei rfloo d contro l project withi n th e area . Betwee n 199 1 an d 1998 , ther e hav e bee n seve n settlement s wit h curren t an d forme r owners/operator s an d wit h th e Tow n o f Norwoo d a t th e Norwoo d PCB s Superfun d Site . On e o fth e settlement s (i n 1997 ) wa s a Consen t Decre e tha t wa s entere d betwee n Cornel l Dubilie rElectronic s (CDE ) an d Federa l Pacifi cElectri c(FPE ) Compan y(Settlin g Parties ) an d th e Unite d State s an d Commonwealt h o f Massachusetts . Thi s Consen t Decre e require d th e Settlin g Partie s t o perfor m th e followin g remedia l actions : buildin g demolition , soi l an d sedimen t excavation , an d cap/cove ractivities . Groundwate r treatmen t an d Meado wBroo k restoratio n activitie s wer e le d b yEP Ausin g fund s fro m th e Superfun d Trus t Fund . Remedia l Constructio n Activitie s -4 -

### Thre e separat e remediatio n phase s wer e complete d - on e byER A(Phas e 1 ) an d two by

th e Settlin g Partie s (Phase s 2 an d 3) . EP Aals o complete d Meado wBroo k restoratio n 

### activitie s a s part o fPhas e 3 . Th e remediatio n an d restoratio n phase s ar e describe d 

### below . Phase

1 - Groundwater

Treatment EP Acomplete d th e constructio n o fa 6,000-square-foo t groundwate rtreatmen t plan t a t th e northeaster n edg e o f th e Sit e i n Novembe r199 5 unde rth e constructio n managemen t o fth e U.S . Arm yCorp s o fEngineers (USAGE) . EP Aan d MADE P performe d a pre-fina l inspectio n o f th e plan t o n Januar y11 , 1996 , afte rwhic h th e treatmen t plan t bega n operating . Durin g constructio n o f th e groundwate rtreatmen t plan t foundation , PCB-contaminate d soi l wa s excavated , relocated , an d stockpile d on-site . PCB-contaminate d soi l fro m fou r outlyin g area s wa s als o excavated , relocated , an d stockpile d on-site . Thes e soil s (approximatel y2,00 0 cubi cyards ) wer e subsequentl yconsolidate d o n sit e unde r cap/cove rarea s (se e Phas e 3 a activitie s below) . Aserie s o fnin e extractio n well s locate d i n th e northeas t portio n o fth e Sit e collecte d contaminate d groundwater . Onc e collected , th e wate rwa s pumpe d int o th e plan t an d inorgani ccontaminant s wer e remove d i n a precipitatio n proces s wher e metals , i n th e 

### for m o fparticulates , settl e ou t o fth e water . Afte rmetal s wer e remove d vi a precipitation , th e remainin g solid s wer e remove d vi a filtration . Th e sludg e wa s the n presse d an d th e resultin g filte rcak e dispose d a t a n off-sit e disposa l facility . Organi ccontaminants , includin g PCBs , wer e remove d i n a n ai rstripper/carbo n adsorptio n system . Durin g thi s 

### proces s VOC s wer e transferre d fro m th e wate rt o th e ai rstream . Acatalyti coxidatio n uni t the n destroy s th e VOC s i n th e ai rstrea m befor e bein g discharge d t o th e atmosphere . Wate rexitin g th e ai rstrippe rwa s the n force d throug h tanks containin g activate d carbo n tha t adsor b remainin g organi ccontaminant s an d serve s a s a las t polishin g ste p befor e th e treate d wate rwa s teste d an d discharge d t o Meado wBrook . Betwee n Marc h 199 6 an d Jun e 2000 , approximatel y16. 3 millio n gallon s o f groundwate r wer e treate d an d abou t 26 2 pound s o f chlorinate d VOC s wer e remove d fro m th e groundwate rbeneat h th e Site . Th e treatmen t plan t wa s constructe d fo ra cos t o f approximatel y$1 1 millio n (includin g sit e preparation , construction , an d initia l stage s o f operation ) an d wa s operate d an d maintaine d fo ra cos t o f approximatel y$500,00 0 pe r year . Monitorin g an d extractio n well s wer e sample d quarterl yan d hav e bee n sample d o n 2 7 occasion s sinc e startup . Operatio n o fth e groundwate rtreatmen t plan t wa s suspende d i n Jun e 200 0 whil e EP A considere d th e effec t o f MADEP' s "lo wus e an d value " determinatio n fo rsit e groundwater . Base d o n thi s determination , groundwate rbeneat h an d i n th e vicinit yo f th e Sit e wa s n o longe rconsidere d t o b e a potentia l drinkin g wate rsourc e an d unde rth e stat e program , th e GW- 3 standard s woul d apply . Th e GW- 3 designatio n consider s th e impact s an d risk s associate d wit h th e discharg e o f groundwate rt o surfac e water . A t th e -5 -

### tim e th e GWT P operation s wer e suspended , groundwate rconcentration s wer e belo w

MADE P GW- 3 standard s fo ral l contaminant s excep t fo r1,2,4-trichlorobenzen e (TCB ) an d PCBs . Th e origina l cleanu p level s i n th e 198 9 RO D wer e base d o n drinkin g wate r criteria , namel yth e Maximu m Contaminan t Level s (MCLs) ; however , n o MC L existe d fo r PCB s a t tha t time . Moreover , th e 198 9 RO D conclude d that , du e t o th e continue d presenc e o fPCB s i n th e saturate d soil s tha t i t woul d b e technicall yinfeasibl e t o reduc e PC B level s i n groundwate rt o a health-base d groundwate rcleanu p level . Thus , n o clean-u p leve l wa s establishe d fo rPCBs . Thi s ES D doe s not alte rthat determinatio n and , thus , n o PC B cleanu p leve l ha s bee n set . Ris k t o exposur e t o PC B contaminatio n i n groundwate rwil l continu e t o b e controlle d vi a institutiona l control s restrictin g th e us e o fgroundwater . EP Aals o conducte d Site-specifi cris k assessmen t activitie s i n respons e to th e revise d groundwate rclassificatio n an d propose d redevelopmen t plans . Ris k assessmen t activitie s evaluate d huma n exposur e t o VOC s volatilizin g fro m groundwate ran d th e vados e zon e int o th e indoo rai ro fa potentia l buildin g o n th e Sit e an d ecologica l exposur e t o groundwate r contaminant s tha t maydischarg e int o Meado wBrook . Othe rtha n th e inactiv e groundwate r treatmen t plant , ther e ar e currentl yn o building s a t th e Sit e locate d abov e area s o fgroundwate r contamination . A s th e resul t o fthes e ris k assessments , risk-base d actio n level s (RBALs ) wer e calculate d fo rth e Sit e groundwate ri n Marc h 2003 . Becaus e exposur e t o contaminant s a t o r belowthes e RBAL s wil l no t presen t a n unacceptabl e ris k t o huma n healt h an d th e environment , thes e level s hav e becom e th e ne wgroundwate rperformanc e standard s fo rth e Site .

Tabl e 1 : Revise d Groundwate rCleanu p Standard s

Contaminan t o f Potentia l Concer n Tota l 1 ,2-Dichloroethene s (DCE ) Trichloroethen e (TCE ) Tetrachloroethen e (PCE ) Viny l Chlorid e 1,2,4-Trichlorobenzen e (DCB ) 1 ,4-Trichlorobenzen e (TCB ) Ris k Base d Actio n Level s (RBALs) : Ne w Groundwate rCleanu p Standard s Establishe d b y thi s Explanatio n o f Significan t Difference s

(mg/L ) 3,66 0 108 3 7 31 0 3 4 4. 6 

### Becaus e n o groundwate rcleanu p leve l fo rPCB s wa s established , a n evaluatio n o fth e potentia l impact s o fresidua l PC B groundwate rcontaminatio n o n Meado wBroo k wa s necessary . Thi s evaluatio n wa s complete d i n Jul y200 4 an d summarize d i n a repor t entitle d Phas e I I Ecologica l an d Huma n Healt h Ris k Summar yReport . Base d o n a n analysi s o fth e residua l groundwate rconcentration s o fVOC s an d PCBs , n o huma n healt h concern s base d o n discharg e t o Meado wBroo k wer e identified . I n addition , th e surfac e wate rAmbien t Wate rQualityCriteri a (AWQC ) fo rPCB s wa s exceede d a t th e -6 -

### midstrea m an d downstrea m station s i n th e 26t h samplin g round . Notwithstandin g thes e

exceedances , th e result s o fa site-specifi cecologica l ris k assessment , unde rexistin g conditions , i t wa s determine d that th e level s ofPC B i n MeadowBroo k surfac e wate ran d sedimen t d o no t represen t a ris k t o th e environment . Periodi csurfac e wate ran d sedimen t monitorin g i n Meado wBroo k wil l continu e t o b e conducte d t o evaluat e long ter m complianc e wit h AWQC s an d t o ensur e tha t the yd o no t increas e t o a leve l tha t 

### ma ypos e a n unacceptabl e ris k t o huma n healt h o rth e environment . A s outline d i n Appendi xA , Ambien t Wate rQualityCriteri a (AWQCs ) hav e bee n adde d a s action specifi cstandard s fo rmonitorin g wate rqualit yi n Meado wBrook . A s par t o fth e evaluatio n o fPCB s i n Meado wBroo k surfac e wate ran d sedimen t wer e collected ; elevate d concentration s o f PCB s wer e detecte d i n on e surfac e soi l sampl e collecte d fro m a woode d are a adjacen t t o th e Tow n o f Norwoo d Municipa l Ligh t Department' s substatio n o n Dea n Street . Thi s dat a poin t containe d 2 4 pp m o fPCBs . A secon d dat a poin t i n th e vicinit ycontaine d 4. 2 ppm . Th e 199 6 RO D Amendmen t se t a surficia l soi l cleanu p leve l fo rPCB s i n th e woode d are a nort h o f Meado wBroo k at 1 0 ppm . Thi s concentratio n represente d a n incrementa l carcinogeni clifetim e ris k o f 5 x 10~ 6 , base d o n exposur e assumption s associate d wit h a n olde rchil d (ag e 6 -16 ) playin g i n thi s area . Applyin g a simila rexposur e scenari o t o th e off-sit e are a adjacen t t o th e sub-statio n dictate s a n incrementa l carcinogeni clifetim e ris k o f 1 x10~ 5 fo rth e maximu m concentratio n detecte d i n thi s area . Sinc e thi s fall s withi n EPA' s 10" 4 t o 10~ 6 acceptabl e ris k range , n o furthe rinvestigatio n o ractio n i n thi s are a a s par t of th e Norwoo d PC B 

### Superfun d Sit e i s believe d t o b e necessary . EP Aconducte d quarterl ygroundwate rmonitorin g fro m Apri l 199 6 unti l Octobe r2002 . Surfac e wate rsample s wer e als o collecte d fro m Meado wBroo k durin g th e las t nin e quarterl ysamplin g rounds . EPAi s i n th e proces s of completin g a n additiona l roun d of groundwate rmonitorin g befor e th e en d o f 2005 . EP Awil l us e th e monitorin g result s t o furthe rasses s th e hydrologica l impact s sinc e th e shu t down , an d ma yus e thes e result s t o determin e whethe ran yadditiona l (future ) groundwate rremediatio n wil l b e necessary . I fth e result s o f th e monitorin g lea d EP At o determin e tha t additiona l activ e groundwate r extractio n an d treatmen t i s not necessary , th e groundwate rtreatmen t pla n wil l b e decommissioned . Additiona l groundwate rdat a wil l b e collecte d periodicall ya s part o f overal l Operatio n an d Maintenance activitie s performe d b yth e Settlin g Partie s an d wil l b e evaluate d durin g eac h Five-yea rRevie wfo rth e site . Phase 2 - Building Demolition I n accordanc e wit h th e 199 6 RO D Amendmen t an d th e 199 7 Consen t Decre e betwee n EP Aan d th e Settlin g Parties , th e 90,000-square-foot , slab-on-grad e Gran t Gea rbuildin g wa s demolishe d (rathe rtha n bein g decontaminate d i n accordanc e wit h th e 198 9 ROD) . 

### Th e one-stor

ybuildin g wa s originall yconstructe d i n 194 2 an d containe d a subgrad e boile rroo m an d two smal l secon d floo rmezzanin e areas . Th e buildin g consiste d mainl y o fa larg e ope n productio n are a wit h severa l smalle rarea s sectioned-of f fo rus e a s offic e an d storag e space . Demolitio n activitie s too k plac e betwee n Octobe r199 6 an d

- 7

### Februar

y199 7 an d wer e performe d b yGZAGeoEnvironmental , Inc . fo rth e Settlin g Parties . USAG E provide d on-sit e constructio n oversight . ER Aan d MADE P performe d a fina l inspectio n o n Februar y6 , 1997 . Th e followin g activitie s wer e complete d durin g th e buildin g demolitio n phase :

_inventory , consolidation , an d off-sit e disposa l o f wast e remainin g fro m th e forme r facilit yoperations ;

_abatemen t an d off-sit e disposa l o f asbestos-containin g material s fro m th e building ;

_closure o f buildin g drainag e syste m includin g remova l an d disposa l o f fre e liquid s an d sedimen t fro m on-sit e manhole s an d groutin g o f buildin g drai n lines ;

_remova l an d off-sit e disposal/recyclin g o fexterio rstee l siding ;



### _remova l an d shreddin g o fcontaminate d woode n roo fdeckin g (dispose d on-sit e unde rcap/cove rarea s durin g phas e 3) ;

_remova l an d crushin g o f brick , concrete , an d wallboar d (dispose d on-sit e unde r cap/cove rarea s durin g phas e 3) ;

_disposa l o f remainin g facilit yequipmen t an d certai n buildin g materials/debri s i n th e subgrad e boile rroom , fillin g th e remainin g voi d space s wit h "flowabl e fill" , an d constructin g a 14-inc h thic k structura l sla b ove rth e boile rroo m area ;

_remova l an d off-sit e recycling/disposa l o ftw o 275-gallo n an d on e 750-gallo n empty 

### abovegroun d condensatio n collectio n tanks ; an d

_remova l an d disposa l i n th e boile rroo m o f a 1,000-gallo n empt yundergroun d tan k (10 0 gallon s o f wast e oi l dispose d off-site) . O n January20 , 1999 , ER Agrante d conditiona l approva l o f th e buildin g demolitio n Remedia l Constructio n Repor t (RCR) . Fina l approva l wa s grante d o n Augus t 8 , 2001 . Phase 3 - Soil/Sediment

Remediation

Phase 3a - Cap/Cover I n accordanc e wit h th e 199 6 RO D Amendmen t an d th e 199 7 Consen t Decre e betwee n ER Aan d th e Settlin g Parties , PCB-contaminate d soi l an d sedimen t wer e consolidate d o n sit e unde rca p an d cove rarea s (rathe rtha n bein g treate d vi a solven t extractio n a s require d b yth e 198 9 ROD) . Cap/cove ractivitie s too k plac e betwee n Apri l 199 7 an d Augus t 199 8 an d wer e performe d b yGZAGeoEnvironmental , Inc . fo rth e Settlin g Parties . USAG E provide d on-sit e constructio n oversight . ER Aan d MADE P performe d a fina l inspectio n o n Augus t 11 , 1998 . Th e followin g activitie s wer e complete d durin g th e cap/cove rphase :

_Consolidatio n o f approximatel y2,00 0 cubi cyard s o f PCB-contaminate d soi l stockpile d on-sit e b yER Afro m groundwate rtreatmen t plan t constructio n an d outlyin g area s excavate d durin g Phas e 1 ; 

### Consolidatio n o fapproximatel y1,60 0 cubi cyard s o fPC B contaminate d soi l stockpile d o n th e adjacen t Reardo n property ;

_Excavatio n o f PCB-contaminate d sedimen t i n Reac h 1 , 2 , an d 3 o f Meado w Broo k (t o th e excavatio n grade s establishe d i n USAGE' S restoratio n plans ) an d consolidatio n o n site ;_Remova l o f additiona l staine d sedimen t i n Reac h 1 an d consolidatio n o n site ;

Excavatio n o f o n an d off-sit e PC B contaminate d soil s an d consolidatio n o n site ;

_Excavatio n o f "hot spot " soil s belowwate rtabl e an d disposa l o n sit e abov e th e wate rtable ;

_Remova l an d disposa l o f on e 10,000-gallo n an d on e 20,000-gallo n undergroun d fue l oi l tanks ; Installatio n o f stor m wate rrunoff control/drainage ; an d

_Installatio n o fasphal t ca p (approximatel y4. 5 acres ) an d grave l cover s (approximatel y1. 6 acres) .



### _Constructio n o fstor m wate rdetentio n basi n (fo rbot h remedia l an d redevelopmen t purposes) ;

_Installatio n o f subsurfac e drainag e structures ; Cap/cove rremediatio n activitie s wer e conducte d i n coordinatio n wit h certai n propose d redevelopmen t activities . Redevelopmen t plan s hav e no t bee n finalized . Th e followin g 

### redevelopmen t activitie s wer e als o complete d durin g thi s phase :

_Constructio n o ftw o retainin g walls ; an d

_Installatio n o f electrica l condui t an d ligh t pol e bases . ER Areceive d th e fina l Soil/Broo k Remediatio n RC R i n Septembe r2003 . I n accordanc e wit h th e Consen t Decree , th e Settlin g Partie s wil l b e responsibl e fo r1 ) performin g al l O& M activitie s i n orde rt o maintai n th e integrityan d effectivenes s o f ca p an d cove rareas , an d 2 ) conductin g appropriat e monitorin g activitie s t o asses s th e protectivenes s an d performanc e o f th e remedy . Thes e activitie s ar e documente d i n O& M an d environmenta l monitorin g wor k plan s finalize d i n Novembe r2004 . Th e Settlin g Parties ' estimate d cos t fo rcompletin g phase s 2 an d 3 a i s $6. 6 million . Phase 3b - Meadow Brook Restoration I n accordanc e wit h th e 199 6 RO D Amendmen t an d afte rexcavatio n o fcontaminate d Broo k sediment s b yth e Settlin g Parties , EP A(unde rth e constructio n managemen t o f USAGE ) restore d an d stabilize d th e sid e slope s an d botto m o f th e excavate d portion s o f Meado wBroo k

t o th e specification s provide d b yth e Tow n o fNorwoo d a s par t o fthei r floo d contro l project . Althoug h th e sedimen t clean-u p leve l fo rPCB s i n Broo k wa s 1 ppm , th e Broo k

wa s onl yexcavate d t o th e depth s require d t o meet th e contours o f th e floo d contro l project . Th e sid e slope s an d botto m o f th e Broo k wer e the n restore d wit h a laye ro fgeotextil e fabri can d appropriat e restoratio n material s (i.e. , ri p rap , interlockin g concret e blocks , o rprecas t concret e culver t sections ) tha t covere d an yremainin g contaminatio n locate d a t depth s belo wth e floo d contro l contours . Restoratio n activitie s i n Reac h 1 o f Meado wBroo k (adjacen t t o th e Site ) too k plac e betwee n Octobe r199 7 an d Decembe r1997 . Du e t o concern s relate d t o th e us e o f th e interlockin g concret e block s o n th e steepe rslope s withi n Reac h 2 , a decisio n wa s mad e t o utiliz e precas t 

### -9 -concret e culver t sections . Thi s redesig n effort , a s wel l a s hig h wate rconditions , resulte d i n delay s i n completin g restoratio n activitie s i n Reac h 2 an d 3 . Reac h 2 an d 3 activitie s too k plac e betwee n Apri l 199 9 an d Jul y1999 . ER Aan d MADE P performe d a fina l inspectio n o n Augus t 11 , 1999 . Th e followin g activitie s wer e complete d durin g th e Broo k restoratio n phase :

_Preparatio n o fBroo k sid e slope s an d botto m (excavat e o rbackfill ) consisten t wit h floo d contro l contours an d restoratio n materials ;

_Installatio n o f ri p ra p (upstrea m portion ) an d interlockin g concret e blocks (downstrea m portion ) o n to p o f geotextil e i n Reac h 1 ;

_Installatio n o fprecas t concret e culvert section s i n upstrea m portio n o fReac h 2 ;

_Installatio n of ri p ra p o n to p of geotextil e i n downstrea m portio n of Reac h 2 ;

_Installatio n o f ri p ra p 10 0 fee t int o Dea n Stree t culvert (Reac h 3) ;

_Installatio n o f topsoi l an d see d t o to p o f slop e an d i n void s o f interlockin g 

### concret e blocks ;

_Encasemen t o ftw o sewe rsypho n line s acros s th e Brook ;

_Constructio n o fa support structur e fo ra 3 0 inc h sewe rmai n adjacen t t o th e Brook ; an d



### _Restoratio n o fwor k

area s (replac e fencing , hydroseed , plantings) . Meado wBroo k

restoratio n activitie s wer e conducte d fo ra cos t o fapproximatel y $775,000 . Th e fina l Meado wBroo k Restoratio n Repor

t wa s prepare d b yUSAG E an d wa s submitte d t o ER Ao n Februar y1 , 2002 . C . Summar y o f198 9 RO D Th e remedia l decisio n documente d i n th e 198 9 RO D include d th e excavatio n an d treatmen t b ysolven t extractio n o f approximatel y34,00 0 cubi cyard s o f PCB contaminate d soil s an d sediments . Afte rtreatment , th e RO D require d th e on-sit e backfillin g of soil s an d sediment s t o b e covere d wit h asphal t o rclea n fill , an d th e off-sit e incineratio n o f extracte d PC B oils . Th e origina l remed yals o include d th e flushin g an d cleanin g o f th e Gran t Gea rbuildin g an d drainag e system . Th e RO D als o calle d fo rth e remediatio n o fgroundwater . I n particular , th e RO D require d contaminate d groundwate rt o b e collecte d wit h extractio n wells , treate d i n a n on-sit e treatmen t plant , an d discharge d t o Meado wBrook . Groundwate rtreatmen t include d carbo n absorptio n fo rPCBs , ai rstrippin g fo rVOCs , an d precipitation/filtratio n fo rmetals . Wetlan d restoration , lon g ter m monitoring , an d institutiona l control s restrictin g groundwate rus e wer e als o require d i n th e 198 9 ROD . D . Summary o fth e 199 6 RO D Amendmen t I n orde rt o addres s highe rtha n anticipate d solven t extractio n cost s an d logistica l problem s wit h th e citin g o fsolven t extractio n equipmen t an d i n consideratio n o fth e likel y commercial/industria l reus e o fth e Site , EP Aissue d a RO D Amendmen t i n Ma y1996 . Th e RO D Amendmen t include d th e demolitio n o fth e Gran t Gea rbuildin g an d -10 -excavatio n an d consolidatio n o f PC B contaminate d soil s an d sediment s unde rasphal t

ca p an d grave l cove rareas . Th e amende d remed yals o include d remediatin g a "ho t spot " o f soi l contaminate d wit h TC B belowth e wate rtable . Th e groundwate rremed y remaine d unchange d fro m th e 198 9 ROD . Long-ter m monitoring , ca p an d cove r maintenance , an d institutiona l control s wer e als o requirement s o f th e RO D Amendment . III . BASI S FO R ES P Thi s ES D document s EPA' s decisio n t o modifyth e groundwate rclean-u p level s originall yestablishe d i n th e 198 9 ROD . I n addition , thi s ES D wil l als o documen t mino r change s t o th e soil , sediment , an d buildin g materia l component s o f th e remed yspecifie d i n th e 199 6 RO D Amendment . A . Reclassificatio n o fGroundwate r Groundwate ri s no t currentl yuse d fo rdrinkin g wate ri n th e vicinityo fth e Site . I n May 2001 , MADE P submitte d a "lowus e an d value " determinatio n fo rth e groundwate ri n th e vicinityo f th e Site . Th e Unite d State s Geologica l Surve yha s classifie d th e aquife ra s low-yiel d an d MADE P n o longe rconsider s groundwate rbeneat h thi s sit e t o b e use d a s a drinkin g wate rsource ; thi s i s a significan t chang e i n statu s fro m th e previou s drinkin g wate rclassificatio n i n effec t a t th e tim e th e 198 9 RO D wa s prepared . A s a result , drinkin g wate rstandard s ar e n o longe rappropriat e a s groundwate rcleanu p standards . Instead , RBAL s hav e bee n calculate d whic h ar e protectiv e o fcurren t an d futur e expecte d groundwate ruse . A s a resul t o f th e revise d groundwate rclassification , site-specifi cris k assessmen t activitie s wer e conducte d t o ensur e tha t revise d groundwate rcleanu p level s woul d no t pos e a n unacceptabl e ris k t o huma n healt h an d th e environment . Additiona l ris k assessmen t activitie s wer e require d t o evaluate d th e following : • huma n exposur e t o VOC s volatilizin g fro m groundwate rand/o ron-sit e contaminate d soil s int o th e indoo rai ro f a potentia l buildin g o n th e Site , • huma n exposur e t o contaminate d soi l an d groundwate rwhic h ma yaris e fro m a constructio n worke rexposur e scenario , an d • ecologica l exposur e t o groundwate rcontaminant s tha t ma ydischarg e int o Meado wBrook . Othe rtha n th e inactiv e groundwate rtreatmen t plant , ther e ar e currentl yn o building s a t th e Sit e locate d abov e area s o fgroundwate rcontamination . However , base d o n th e update d assessment , i t wa s determine d tha t a vapo rbarrie r(o rothe rmean s o f mitigatin g indoo rvapors ) woul d b e require d i fa structur e wer e buil t o n site . An yspecifi c 

### redevelopmen t proposa l woul d nee d t o compl ywit h restriction s outline d i n th e Institutiona l Control s fo rth e Sit e calle d fo ri n th e RO D an d Amende d ROD . Regardin g th e ecologica l effect s o f contaminant(s ) dischargin g t o Meado wBrook , RBAL s wer e calculate d base d i n th e expecte d attenuatio n o fgroundwate rcontaminatio n acros s th e sit e (prio rt o discharge ) an d th e dilutio n o f an ydischarg e wit h th e remainde ro fth e stream . Wit h th e exceptio n o f PCBs , fo rwhic h a clea n u p ga l ha s no t bee n

proposed , al l contaminant s mee t th e RBALs . Thes e ne wRBAL s ar e appropriat e 

### becaus e the yd o no t presen t a n unacceptabl e ris k t o huma n healt h o rth e environment , ar e cos t effectiv e becaus e activ e treatmen t wil l no t b e necessary , resultin g i n $500,00 0 

### saving s pe ryear . A s note d above , sit e groundwate ra s wel l a s Meado wBroo k surfac e 

### wate ran d sedimen t wil l continu e t o b e monitore d t o ensur e tha t th e remed yremain s protectiv e i n th e long-term . ER Awil l als o continu e conductin g Five-yea rReview s o f th e remed yt o ensur e tha t i t remain s protectiv e an d t o evaluat e complianc e wit h th e Applicabl e o rRelevan t an d Appropriat e Requirement s (ARARs ) outline d i n Appendi xA t o thi s BSD . B . Soil , Sediment , Buildin g Materia l Componen t Change s Th e 199 6 RO D Amendmen t require d tha t th e undergroun d storag e tan k (LIST) tha t serve d th e Gran t Gea rbuilding' s boile rb e decommissione d i n accordanc e wit h applicabl e regulations . Asecon d LIS Twa s discovere d durin g th e 199 7 buildin g demolitio n phas e o f remediation . Therefore , bot h UST s wer e remove d an d dispose d off-sit e a s directe d b yth e Stat e Fire Marshall . Staine d soil s belo wth e tank s wer e excavate d an d als o dispose d o foff-site . Th e Settlin g Partie s complete d thi s wor k fo r approximatel y$118,000 , a minima l amoun t whe n compare d t o th e tota l cos t o fth e Sit e remedia l action . Th e 199 6 RO D Amendmen t require d tha t Meado wBroo k sediment s b e remove d onl yt o th e elevatio n require d fo rth e restoratio n o f th e botto m an d side-slope s o f th e Brook . However , staine d sediment s i n Meado wBroo k i n th e are a o fth e forme rGran t Gea r buildin g roo f drai n outfal l wer e discovere d durin g th e 199 7 soil/broo k phas e o f remediation . Additiona l staine d soi l wa s identifie d durin g detentio n ber m constructio n activities . Th e Settlin g Partie s excavate d th e staine d sediment s an d soil s an d the n 

### dispose d thes e material s on-sit e unde rth e asphal t cap . Th e Settlin g Partie s complete d thes e activitie s fo rapproximatel y$63,000 , a minima l amoun t whe n compare d t o th e tota l cos t o f th e Sit e remedia l action . IV . DESCRIPTIO N O F SIGNIFICAN TDIFFERENCE S EP Ai s changin g th e groundwate rclean-u p level s du e t o a chang e i n th e groundwate r classification . Othe rmino rchange s t o th e soil , sediment , an d buildin g materia l component s o fth e remed yar e als o bein g documented . A s a resul t o fthes e changes , EP Aconsider s th e modifie d remed yt o b e adequatel yprotectiv e o f huma n healt h an d th e environment . Adescriptio n o fth e change s follow s below . A . Revise d Groundwate rCleanu p Level s 

### I n respons e t o th e revise d groundwate rclassification , supplementa l ris k assessmen t activitie s wer e conducted . Thes e effort s resulte d i n th e calculatio n o f RBAL s fo rth e Site . Tabl e 2 belo wshow s a compariso n o fth e 198 9 ROD-specifie d groundwate rclean u p level s an d th e ne wRBALs . Th e assessment s hav e als o demonstrate d tha t level s fo r th e contaminant s o fconcer n a t th e Sit e ca n b e se t a t th e revise d level s withou t causin g 

### -12 -unacceptabl e ris k t o huma n healt h an d th e environment . Moreover , th e Unite d State s 

### an d th e Commonwealt h of Massachusett s wil l incu ra significan t saving s i n Sit e relate d cost s fro m long-ter m groundwate rextractio n an d treatment . Tabl e 2 : Compariso n o f Groundwate rClean-u p Goal s fro m 198 9 RO D an d ne wRBAL s

Contaminan t o fPotentia l Concer n Tota l 1 ,2-Dichloroethene s (DCE ) Trichloroethen e (TCE ) Tetrachloroethen e (PCE ) Viny l Chlorid e 1,2,4-Trichlorobenzen e (DCB ) 1 ,4-Trichlorobenzen e (TCB ) Groundwate rCleanu p Standard s Establishe d i n 198 9 Recor d o f

Decisio n (mg/L ) 0.17 5 0.00 5 0.00 5 0.00 2 0.3 5 0.00 5 Ris k Base d Actio n Level s (RBALs) : Ne wGroundwate r Cleanu p Standard s Establishe d b ythi s Explanatio n o f Significan t

Difference s (mg/L ) 3,66 0 10 8 3 7 31 0 3 4 4. 6 B . Soil , Sediment , Buildin g Materia l Componen t Change s Durin g buildin g demolitio n an d soil/broo k remediatio n activities , differen t Sit e condition s wer e encountere d tha n wer e originall yanticipated . Tw o UST s wer e identifie d rathe r 

### tha n on e an d additiona l staine d soil s an d sediment s wer e discovered . I n orde rt o preven t th e migratio n o f contaminant s int o groundwate ro rsurfac e water , bot h UST s an d th e staine d soil s an d sediment s wer e remove d an d dispose d o f properl ya t minima l additiona l cost . V . SUPPOR TAGENC YCOMMENT S MADE P ha s participate d wit h ER Ai n developin g thi s BS D an d concur s wit h th e changes . Se e Appendi xB fo rth e MADE P concurrenc e letter . VI . STATUTOR YDETERMINATION S ER Aha s determine d tha t th e selecte d remed yspecifie d i n th e RO D an d RO D Amendment , an d th e change s pursuan t t o thi s ESD , remai n protectiv e o f huma n healt h an d th e environment , compl ywit h Federa l an d Stat e requirement s tha t ar e applicabl e o r relevan t an d appropriate , an d ar e cost-effective . Th e revise d remed yutilize s permanen t solution s an d alternativ e treatmen t technologie s t o th e maximu m exten t practicabl e fo r 

### -13-thi s Site . Alis t o fApplicabl e o rRelevan t an d Appropriat e Requirement s (ARARs ) i s

provide d a s Appendi xAt o thi s ESD . VII . PUBLI C PARTICIPATIO N Thi s ES D an d supportin g informatio n ar e availabl e fo rpubli crevie wa t th e location s identifie d withi n thi s document . I n addition , a notic e o f availabilit yo f th e ES D wil l b e provide d t o a loca l newspape ro f genera l circulation . VIII . DECLARATIO N Fo rth e foregoin g reasons , b ym ysignatur e below , I approv e th e issuanc e o fa n Explanatio n o f Significan t Difference s fo rth e Norwoo d PC B Superfun d Sit e i n Norwood , Massachusett s an d th e change s an d conclusion s state d therein .

jgusarvSfuttfien , /Offic e offSit e i U S ER AReg k frecto r

lediatio n an d Restoratio n Dat e 

### 1

-14 -Appendi xA

Applicabl e o rRelevan t an d Appropriat e Requirement s (ARARs ) Table sAUTHORIT Y REQUIREMEN T

CHEMICA L SPECIFI C ARARs : Federa l Criteria , Technica l Basi s fo r Derivin g Sedimen t Advisories , an dGuidanc e Qualit y Criteri afo r Non-ioni c Organi c Contaminant s fo r

th e Protectio no f

Benthi c Organism s Usin g Equilibriu mPartitionin g (EPA-822-R-93-011 ) cleanu p levels . Clea nWate r

Ac t Sec . 30 4 Federa l Ambien t

Wate r Qualit y Criteri a 3 3 US C 1314;40CF R122.4 4

EP ACarcinogeni c Assessmen t Grou p Potenc y Factor s EP ARis k Referenc e Dose s (RfDs ) STATU S REQUIREMEN TSYNOPSI S T o b e Thi s guidanc e i s use dt o establis hcriteri at o Considere dprotec t

th e aquati c organism s i nstream s an dt o determin e environmenta l ris k withi nth e sedimen t

an dt o se t sediment . Relevan t an dFedera l AWQ C ar e criteri afo r protectio no f Appropriat e huma nhealt han daquati c organism s whic hhav e

bee ndevelope dfo r

carcinogeni c an dBroo k noncarcinogem c compounds . AWQ C ar e develope dunde r th e Clea nWate r

Ac t (CWA ) a s guideline s fro mwhic hstate s develo p wate r qualit y standards . T o b e Potenc y factor s ar e develope db y th e EP Afro m Considere dHealt hEffect s Assessment s o r Evaluatio nb y th e Carcinogeni c Assessmen t

Group . T o b e RfD s ar e doe s level s develope db y th e EP Afo r Considere dnon-carcinogeni c effects . ACTIO NTAKE NT O ATTAI N ARAR s Th e criteri aestablishe dwere use dt o evaluat e risk s t o aquati c organism s expose dt o contaminate dwate r entraine d AWQ C wer e use dt o characteriz e risk s t o fres hwate r

aquati c lif ei nMeado w Broo k

EP ACarcinogeni c Potenc y Factor s wer e use dt o complet e th e individua l incrementa l cance r

ris k resultin g fro m exposur e t o sit e contaminants . EP ARfD s wer e use dt o characteriz e risk s du e t o exposur e t o contaminant s o n site . LOCATIO N SPECIFI C ARAR s Federa l Regulator y Wetland s Executiv eOrde r (E O 11990 ) Applicabl e 4 0 CF RPar t

6 , Appendi x A Floodplain s Executiv e Orde r (E O 11988 ) Applicabl e 4 0 CF RPar t

6 , Appendi x A Clea nWate r

Ac t (CWA ) - Sectio n40 4 Applicabl e Dredg e an dFil lRequirement s (3 3 U.S.C . 1344 , 4 0 CF RPar t 230 ) Unde r thi s regulation . Federa l agencie s ar e require dt o minimiz e th e destruction , loss , o r degradatio no l wetlands , an dpreserv e an d enhanc e natura l an dbeneficia l value s o f wetlands . Federa l agencie s ar e require dt o reduc e th e ris k o f floo dloss , t o minimiz e th e impac t o f floods , an dt o restor e an dpreserv e th e natura l an d beneficia l value s o f

floodplains . N o activit y tha t

adversel y affect s awetlan dshal l b e permitte di f

apracticabl e alternativ e tha t ha s les s effec t i s available . An y redevelopmen t o r O & M wil l includ e al l al lpracticabl e mean s o f

minimizin g har mt o wetlands . Th e remedia l actio nwa s designe dt o kee p al l activitie s ou t

o f th e floodplai nt o th egreates t

exten t practicable . Ongoin g monitorin g an dO& M activitie s i nan d adjacen t t o Meado w Broo k

o r an y othe r Sit e wetland s wil lmee t

thes e standards . 1-is han dWildlif eCoordinatio nAc t 1 6 U.S.C' . 6(> l Applicabl e Befor e undertakin g an y Federa l actio ntha t cause s th e modificatio no f

an y bod y ol " wate r

o r affect s fis han dwildlife . Federa l an dStat e fis han dwildlif eagencie s wil lb e consulte dconcernin g an y monitorin g an dO& M activitie s i nan dadjacen t

t o Meado w Brook . A- lAUTHORIT Y REQUIREMEN T Resourc e Conservatio nan dRecover y Ac t (RCRA ) Locatio nStandard s (4 0 C.F.R . 264.18 ) STATU S REQUIREMEN TSYNOPSI S Relevan t an dThi s regulatio noutline s th e requirement s fo r Appropriat e constructin g aRCR Afacilit y o na100-yea r floodplain . Stat e Regulator y Massachusett s Wetland s Protectio nAc t (M.G.L . c.13 1 Sectio n4 0 :310CM R10.00 ) Massachusett s Waterway s Regulation s (M.G.L . c.2l . Section s 26-53 ; 31 4 CM R9.00 ) Applicabl e Thes e regulation s outlin eth e requirement s necessary t o wor k

withi n10 0 fee t

o f awetland . Applicabl e Regulate s wor k withi nwaterways , includin g wate r qualit y protection . ACTIO N SPECIFI C ARAR s Federa l Regulator y Resourc e Conservatio nan dRecover y Ac t Requirement s (RCRA ) Subtitl e C (4 0 C.F.R . 260-262 )

Toxi c Substance s Contro l Ac t (TSCA) , 1 5 U.S.C . § § 260l,e/.«?<7 , 4 0 C.F.R . 761.7 5 Toxi c Substance s Contro l Ac t (TSCA) , (4 0 C.F.R . 760.60 ) C'lea nWate r

Ac t - Sec . 30 4 Federa l Ambien t

Wate r Qualit y Criteri a 3 3 USC ' 1314;40CF R122.4 4 Applicabl e RC'R Aregulate s th e generation , transport , (fo r generate dstorage , treatment , an ddisposa l o f hazardou s wastes)/ ; Wast e CERCI. Aspecificall y require s (i n Relevan t an dSectio n121(d)(3 ) tha t hazardou s substance s Appropriat e fro mrespons e action s b e dispose do f a t facilitie s (fo r closure / i ncomplianc e wit hSubtitl eC o f RCR A pos t closure ) Applicabl e Establishe s standard s fo r PC B landfills , includin g permittin g waiver s fo r

cla y soils , syntheti c liner , 5 0 fee t t o wate r table , an dleachat e collectio n requirement s upo nafindin g b y th e Regiona l Administrator . Establishe s treatmen t

an ddisposa l standard s fo r PC B waste s generate da s par t o f redevelopment , monitorin g o r

O& M activities . Relevan t an dAWQ C ar e develope dunde r th e Clea nWate r

Ac t Appropriat e (CWA ) a s guideline s fro mwhic hstate s develo p

wate r qualit y standards . ACTIO NTAKE NT O ATTAI N ARAR s Hazardou s wast e dispose do f o r generate dwithi nth e floodplai no f

Meado w Broo k

wil l b e manage dt o preven t areleas e o f

hazardou s wast e i nth e even t o f a floo devent . Al lredevelopment , monitoring , o r O& M wor k

withi n area s regulate dunde r

thi s standar dwil l b e conducte d i ncomplianc e wit hthes e regulations . Al lredevelopment , monitoring , o r O& M wor k

withi n o r adjacen t t o Meado w Broo k

wil l compl y wit hthes e standards . Waste s generate ddurin g monitorin g o r O & M activitie s wil lb e characterize d an dhandle di naccordanc e wit happlicabl e RC'R A regulations . Waste s left

i nplac e unde r

th e ca p wil lb e manage di ncomplianc e wit hclosur e an dpost-closur e standards . Closure/pos t

closure s standard s (incorporatin g waiver s invoke dunde r

th e RO D amendment ) fo r th e cappe dPC B waste s wil l b e followed . Treatmen t an ddisposa l standard s fo r PC B generate dwaste s wil lb e satisfied . AWQC ' ar e use dt o monito r wate r qualit y i nMeado w Broo k

t o asses s th e protectivenes s o f th e remed y

Stat e Regulator y Requirement s Guid e o nRemedia l Action s a t Superfun dT o b e Site s wit hPC B Contaminatio n(OSWE Rconsidere d Directiv e 935 5 4-01 , Augus t 1990 ) Massachusett s Groundwate r Protectio nRelevan t an d Regulation s Appropriat e 31 4 CM R6.0 0 Set s fort hguideline s fo r implementin g remedia l action s fo r

PCB s Thes e regulation s establis hth e criteri afo r classifyin g groun dwate r

an dfo r establishin g monitorin g standards . Ongoin g monitorin g an dO& M activitie s wil l b e conducte dconsisten t

wit hth e goal s o f

thi s guidanc e Groundwate r

ha s bee nreclassifie da s Clas s III , designate dfo r

use s othe r

tha na s asourc e o f

potable , wate r supply . Th e regulation s als o se t standard s tha t wil lb e use dlo r

monitoring .



### A- 2AUTHORIT Y RKQUIRKMEN TSTATU S Massachusett s Ambien t

Ai r Qualit y Applicabl e Standard s REQUIREMEN TSYNOPSI S Thes e regulation s specif y emission s standard s fo r particulate s an dlead . ACTIO NTAKE NT O ATTAI N ARAR s Al l redevelopment , monitorin g an dO& M activitie s wil l b e conducte di namanne r t o minimiz e th e generatio no f

dus t o r othe r hazardou s wastes . Massachusett s Ai r

Pollutio nContro l Regulation s 31 0 C.M.R . 7.0 0 Applicabl e Massachusett s Hazardou s Wast e Regulation s Applicabl e 31 0 C.M. R30.0 0 Regulation s specifi c t o contro l o f odo r an d requirement s fo r

handlin g asbesto s waste s an d fugitiv e dus t

emissions . Regulation s governin g th e generation , treatment , storage , an ddisposa l o f

hazardou s waste . An y odor s an dfugitiv edus t generate db y O&M , redevelopment , an dmonitorin g wil l b e controlled , unde r thes e standards . Thes e regulation s wil lb e followe di nconductin g O&M , monitoring , an dredevelopmen t activities . Potion s o f thes e regulations , whic har e specifi c t o on-sit e PCB s ar e no t

applicabl esinc e PC B ar e adequatel y regulate dunde r TSCA . Massachusett s Hazardou s Wast e Regulation s Applicabl e 310C.M.R . 30.125(b ) Massachusett s Hazardou s Wast e Regulation s Applicabl e 31 0 C.M.R . 30.30 2 Requirement s fo r Toxi c Characteristi c Leachin g Procedur e (TCLP) . Requirement s fo r

an y generato r

o f awast e t o determin e i f

th e wast e i s hazardous . Waste s generate dfo r off-sit edisposa l i nconductin g O&M , monitoring , an dredevelopmen t activitie s wil l b e charactenze dan dhandle di naccordanc e wit h thes e standards . Waste s generate dfo r

off-sit e disposa l i nconductin g O&M , monitoring , an dredevelopmen t activitie s wil lb e characterize dan dhandle di naccordanc e wit h thes e standard s



### A- 3Appendi xB MADE P Concurrenc e Lette r

## COMMONWEALT HO FMASSACHUSETT S EXECUTIV EOFFIC EO FENVIRONMENTA LAFFAIR S DEPARTMEN T O F ENVIRONMENTA L PROTECTIO N ON EWINTE RSTREET , BOSTON , M A0210 8 617-292-550 0 MIT T ROMNE Y ELLE NRO Y HERZFELDE R Governo r Secretar y KERR Y HEALE Y ROBER T W . GOLLEDG EJr . Lieutenan t

Governo r

Commissione r 

### February 15,200 5 Ms . Susa nStudlien , Directo r

RE : Explanatio no f Significan t Offic e o f Site Remediatio nan dRestoratio nDifference s fo r Norwoo dPCB s U S EPA , Suit e 1100 (HIO ) Superfun dSite On e Congres s Stree t

Norwood , MA . 

### Boston , M A02114-202 3 Dea r Ms . Studlien : 

### Th e Departmen t

o f Environmenta l Protectio n(th e Department ) ha s reviewe dth e propose d Explanatio no f

Significan t

Difference s (BSD ) date dFebruary 200 5 fo r th e Norwoo dPCB s (Norwood ) Superfun dSite . Thi s BS D amend s th e origina l 198 9 Recordo f Decisio n(ROD ) an d th e 199 6 Amende dROD . Th e Departmen t concur s wit hth e BS D fo r th e Site . Th e purpos e o f

thi s BS D i s principall y t o adop t ne w groundwate r

cleanu p goals . Mino r

change s 

### ar e als o documente dfo r

th e soil/sourc e remed y a s wel l a s fo r th e remed y implemente dalon g Meado w Brook . Th e Departmen t believe s tha t

thes e change s t o th e remed y wil l no t affec t it s 

### overal l protectiveness . Th e Departmen t

ha s evaluate dth e BS D fo r consistenc y withM.G.L . Chapte r 2I Ean dth e 

### Massachusett s Contingenc y Plan(MCP) . Thi s BS D establishe s ne w groundwate r cleanu p goal s base do nth e Department' s revise dregulatory classificatio nfo r groundwate r

at th e site . A t

th e tim e th e RO D wa s finalized , th e groundwate r at th e site wa s classifie da s apotentia l drinkin g wate r sourc e area . I n199 3 th e groundwate r classificatio nwa s revise dwit hth e groundwate r at an di nth e are ao f

th e site n o longer

considere dapotentia l o f

curren t drinkin g wate r

sourc e area . Thi s chang e i nclassificatio ni s discusse di nth e 200 1 Groundwate r Us e an dValu e Determinatio n 

### prepare db y th e Departmen t an dreflecte di nth e "lo w us e an dvalue " determinatio nassigne dt o th e site groundwater . I nconsideratio no f th e ne w classification , EP Are-evaluate dth e potentia l groundwate r

exposure s an drisk s an drevise dth e cleanu p goals . Th e ne w cleanu p goal s 

### containe di nth e ES D reflec t update dris k

informatio nincludin g huma nhealthan dth e environment . Thi s Informatio nI s availabl e i n alternat e format . Cal l Apre l McCabe , AD A Coordinato ra t1-617-556-1171 . TD D Service - 1-800-298-2207 . DE P o n th e Worl d Wid e Web : http://www.mass.gov/de p

£ J Printed o n Recycled Pape r

### Th e Department appreciate s th e opportunit

y to provide input

o nthi s BS D an dlook s forwar dto th e continuin g implementatio no f th e remedy at

th e Site . I f

yo u hav e an y question s pleas e cal l 

### Danie l Keefe , Projec t

Manager fo r th e Site , at

(617 ) 292-5940 . Sincerely , 

### RichardChlalpin , Assistant

Commissione

r Burea u o f Wast e Sit e Cleanu p e-copy:Bob Ciaciarulo , U S EPA e-file : 05.00 Recordo f

Decision/DEPConcurrenc e Lette r Norwoo dPCB s BS D 200 5Appendi xC

Administrativ e Record Inde xfo rth e Explanatio n o f Significan t Difference s

# Norwoo dPCB s

NPLSite Administrativ e Record Explanatio no f

Significan t

Difference s 

# Operabl e Uni t

1 Inde x Prepare db y EP ANe w Englan d 

# Offic e o f Sit e Remediatio n& Restoratio nIntroductio n to th e Collectio n

Thi s i s th e Administrativ e Recordfo r th e Norwoo dPCB s Superfun dsite , Norwood , MA , O U 1 , Entir e Site , Explanatio no f Significan t

Difference s (BSD) , release dFebruary 2005 . Th e fil e contain s site-specifi c document s an dalis t o f guidanc e document s use db y EP Astaf f i nselectin g arespons e actio nat

the site . Thi s fil e includes , b y reference , th e administrativ e recor dfile s fo r th e Norwoo dPCBs , O U1 Recor do f Decision , issue dSeptembe r 29 , 198 9 an dO U 1 Recor do f Decisio nAmendment , issue dMay 17 , 1996 . Th e administrativ e recordfil e i s availabl e fo r revie w at : Morril l Memorial Librar y Walpol e Stree t Norwood , M A0206 2 (781)769-020 0 (phone ) http://www.ci.norwood.ma.us/librarv/index.htm l EP ANe w Englan dSuperfun dRecord s & Informatio nCente r 1 Congres s Street , Suit e 110 0 (HSC ) Boston , M A0211 4 (b y appointment ) 617-918-144 0 (phone ) 617-918-122 3 (fax ) http://www.epa.gov/region01/superfund/resource/records.ht m Question s abou t

thi s administrativ e recordfil e shoul db e directe dt o th e EP ANe w Englan dsit e manager . A nadministrativ e recordfil e i s require db y th e Comprehensiv e Environmental Response , Compensation , an dLiabilit y Ac t (CERCLA) , a s amende db y th e Superfun dAmendment s an d Reauthorizatio nAc t

(SARA) .A RCollection : 207 7 ES D A RCollectio n Q A Repor t ***Fo rExterna l Use** * 2/23/0 5

03 : REMEDIA L INVESTIGATIO N (RI ) FINA^ Author : FOSTE RWHEELE RENVIRONMENTA LCOR P Addressee : u § ARM Y CORP S O FENGINEER S Do c Date : 04/01/200 0 #ofPages : 12 2 Do cType : REPOR T 4569 p ^;;'FlB|^;1i;C»pW<^'JM^pI^^I ^ DEVELOPMENT OF : RISK-BASED ACTION LEVEL S FORTH E e ; Si:ftift|^ ^ CONCER N IN . 

## ItiSllli ^ " I 2? t•';"''• ••' . " ' ; •-• . . : , . \ ...'.. ' Author : FOSTE RWHEELE RENVIRONMENTA LCOR P Addressee : u s ARM y CORP S O FENGINEER S Do cDate : 03/01/200 2 #o f Pages : 4 0 Do cType : REPOR T ;El|:<p^

^ ''." ? : V. : ; \ w Author : FOSTE RWHEELE RENVIRONMENTA LCOR P Addressee : u s ARM Y CORP S O FENGINEER S Do c Date : 05/01/200 2 #o f Pages : 1 0 Do cType : REPOR T

Author : FOSTE RWHEELE RENVIRONMENTA LCOR P Addressee : u § ARM Y CORP S O FENGINEER S Do c Date : 05/01/200 2 #o f Pages : 12 8 Do cType : REPOR TA RCollection : 207 7 ES D A RCollectio nQ A Repor t ***Fo rExterna l Use** * 2/23/0 5

03 : REMEDIA L INVESTIGATIO N (RI ) t£^Q ^ Author : TETR ATEC H F WIN C Addressee : Do c Date : 07/01/200 4 #o f Pages : 5 2 U S ARM Y CORP S O FENGINEER S - NE WENGLAN D DIVISIO N Do cType : REPOR T 05 : RECOR D O F DECISIO N (ROD )

Author : U S EP AREGIO N1 Addressee : Do cType : REPOR T Do cType : RECOR D O FDECISIO N

Author : U S EP AREGIO N1 Addressee : Do cType : REPOR T

Author : RICHAR D J CHALPI NM ADEP T O FENVIRONMENTA LPROTECTIO N Addressee : SUSA N STUDL i E Ny s E p AREGIO N1 - OFFIC EO FSIT EREMEDIATIO N& RESTORATIO N Do cType : LETTE R Do c Date : 09/29/198 9 #o f Pages : 30 6

Do c Date : 05/17/199 6 #o f Pages : 8 7

Do c Date : 02/15/200 5 #o f Pages : 2A RCollection : 207 7 ES D A RCollectio nQ A Repor t ***Fo rExterna l Use** * 2/23/0 5

05 : RECOR D O F DECISIO N (ROD )

Author : U S EP AREGIO NI Addressee : Do cType : EXPLANATIO NO FSIGNIFICAN TDI P Do cType : REPOR T Do c Date : 02/23/200 5 #o f Pages : 2 3

07 : REMEDIA L ACTIO N (RA )

Author : GZ AGEOENVIRONMENTA LIN C Addressee : Do cType : REPOR T Do cDate : 11/11/199 7 #o f Pages : 22 5

Author : GZ AGEOENVIRONMENTA LIN C Addressee : Do cType : REPOR T Do c Date : 11/11/199 7 SofPages : 50 7

Author : GZ AGEOENVIRONMENTA LIN C Addressee : NORWOO D PC B SUPERFUN D SIT EREMEDIATIO NTRUS T Do cType : REPOR T Do c Date : 09/01/200 3 #o f Pages : 49 1A RCollection : 207 7 ES D A RCollectio n Q A Repor t ***Fo rExterna l Use** * 2/23/0 5

07 : REMEDIA L ACTIO N (RA )

Author : GZ AGEOENVIRONMENTA LIN C Addressee : NORWOO D PC B SUPERFUN D SIT EREMEDIATIO NTRUS T Do cType : REPOR T Do cDate : 09/01/200 3 # o f Pages : 32 4

Author : GZ AGEOENVIRONMENTA LIN C Addressee : NORWOO D PC B SUPERFUN D SIT EREMEDIATIO NTRUS T Do cType : REPOR T Do c Date : 09/01/200 3 #o f Pages : 66 7

Author : GZ AGEOENVIRONMENTA LIN C Addressee : NORWOO D PC B SUPERFUN D SIT EREMEDIATIO NTRUS T Do cType : REPOR T Do c Date : 09/01/200 3 #o f Pages : 53 6

i5*Jl|Sl^a«fjrte^JT»VD'l^ :E n^ W Author : GZ AGEOENVIRONMENTA LIN C Addressee : NORWOO D PC B SUPERFUN D SIT EREMEDIATIO NTRUS T Do cType : REPOR T Do c Date : 09/01/200 3 #o f Pages : 45 0A RCollection : 207 7 ES D A RCollectio nQ A Repor t ***Fo rExterna l Use** * 2/23/0 5

07 : REMEDIA L ACTIO N (RA ) PHASE , VOLUME 5 Author : GZ AGEOENV1RONMENTA LIN C Addressee : NORWOO D PC B SUPERFUN D SIT EREMEDIATIO NTRUS T Do cType : REPOR T

Author : Addressee : GZ AGEOENVIRONMENTA LIN C

NORWOO D PC B SUPERFUN D SIT EREMEDIATIO NTRUS T Do c Date : 09/01/200 3 #o f Pages : 48 8

Do cDate : 09/01/200 3 #o f Pages : 45 9 Do cType : REPOR T

Author : GZ AGEOENVIRONMENTA LIN C Addressee : NORWOO D PC B SUPERFUN D SIT EREMEDIATIO NTRUS T Do cType : REPOR T

Author : TETR ATEC H F WIN C Addressee : U S ARM Y CORP S O FENGINEER S - NE WENGLAN D DIVISIO N Do cDate : 09/01/200 3

Do cDate : 07/01/200 4 #o f Pages : 39 8

#o f Pages : 5 5 Do cType : REPOR T Do cType : SAMPLIN G& ANALYSI S DAT AA RCollection : 207 7 ES D A RCollectio n Q A Repor t ***Fo rExterna l Use** * 2/23/0 5

08 : POS T REMEDIA L ACTIO N

Author : FOSTE RWHEELE RENVIRONMENTA LCOR P Addressee : y s ARM Y CORP S O FENGINEER S - NE WENGLAN D DIVISIO N Do c Date : 01/01/200 3 #o f Pages : 4 7 Do cType : REPOR T

Author : U S EP AREGIO N1 Addressee : Do cType : FIVE-YEA RREVIE WREPOR T Do cType : REPOR T Do c Date : 12/29/200 4 #o f Pages : 8 1

09 : STAT E COORDINATIO N

Author : JA Y NAPARSTE K M ADEP T O FENVIRONMENTA LPROTECTIO N Addressee : DANIE LCOUGHLI NU S EP AREGIO N1 Do cType : LETTE R Do c Date : 05/11/200 1 #o f Pages : 6

Numbe ro fDocument s i n Collection:2 3

### GUIDANC E DOCUMENTS

ER Aguidanc e document s mayb e reviewe d a t th e ER ARegio n I Superfun d Record s Cente ri n Boston , Massachusetts . TITL E EVALUATIO N O F TH E B.E.S.T . SOLVEN TEXTRACTIO N SLUDG E TREATMEN TTECHNOLOGY . TWENTY-FOU R HOU R TEST . DOCDAT E OSWER/EP A I D DOCNUMBE R ___________EP A 600/2-88/051____C027____________________________________________________

_ TITL E NATIONA L OI L AN D HAZARDOU S SUBSTANCE S POLLUTIO N CONTINGENC YPLAN . DOCDAT E OSWER/EP A I D DOCNUMBE R ___________________________C063____________________________________________________

_ TITL E PROTECTIO N O F WETLANDS : EXECUTIV E ORDE R 11990 . 42 FED . REG . 2696 1 (1977) . DOCDAT E OSWER/EP A I D DOCNUMBE R 5/24/1977____________________C003____________________________________________________

_ TITL E APPLICABILIT

YO F PC B REGULATION S T O SPILLS WHIC H OCCURRE D PRIO R T O TH E EFFECTIV E DAT E O F TH E 197 8 REGULATIO N DOCDAT E OSWER/EP A I D DOCNUMBE R 8/3/1979____________________C057____________________________________________________

_ TITL E DEVELOPMEN TO F ADVISOR YLEVEL S FO R POLYCHLORINATE D BIPHENYL S (PCBS ) CLEANUP . DOCDAT E OSWER/EP A I D DOCNUMBE R 5/1/1986_____EP A600/6-86/002____C019____________________________________________________

_ TITL E HANDBOO KFO R STABILIZATION/SOLIDIFICATIO N O F HAZARDOU S WAST E DOCDAT E OSWER/EP A I D DOCNUMBE R 6/1/1986_____EPA/540/2-86-00 1 2308____________________________________________________

_ TITL E SUPERFUN D REMEDIA L DESIG N AN D REMEDIA L ACTIO N GUIDANC E DOCDAT E OSWER/EP A I D DOCNUMBE R 6/1/1986_____OSWE R #9355.0-4 A2011____________________________________________________

_ TITL E DRAFTGUIDANC E O N REMEDIA L ACTION S FO R CONTAMINATE D GROUN D WATE R A TSUPERFUN D SITES . DOCDAT E OSWER/EP A I D DOCNUMBE R 10/1/198 6 OSWE R #9283.1- 2 C022____________________________________________________

_ TITL E SUPERFUN D PUBLI C HEALT H EVALUATIO N MANUA L DOCDAT E OSWER/EP A I D DOCNUMBE R 10/1/1986_____OSWE R#9285.4- 1 5014____________________________________________________

_ TITL E COMPREHENSIV E ENVIRONMENTA L RESPONSE , COMPENSATION , AN D LIABILIT YAC TO F 1980 . AMENDE D B YP L 99-499 , 10/17/86 . DOCDAT E OSWER/EP A I D DOCNUMBE R 10/17/1986___________________C018____________________________________________________

_ TITL E INTERI M GUIDANC E O N SUPERFUN D SELECTIO N O F REMED Y DOCDAT E OSWER/EP A I D DOCNUMBE R 12/24/198 6 OSWE R #9355.0-1 9 900 0

Thursday , Januar

y20 , 200 5 Pag e 1

### GUIDANC E DOCUMENT S

ER Aguidanc e document s mayb e reviewe d a t th e ER ARegio n I Superfun d Record s Cente ri n Boston , Massachusetts . TITL E DATAQUALITYOBJECTIVE S FO R REMEDIA L RESPONS E ACTIVITIES : DEVELOPMEN TPROCES S DOCDAT E OSWER/EP A I D DOCNUMBE R 3/1/198 7 EPA/540/G-87/00 3 210 1 TITL E PC B SEDIMEN TDECONTAMINATIO N - TECHNICAL/ECONOMI C ASSESSMEN TO F SELECTE D ALTERNATIV E TREATMENTS . PROJEC T SUMMARY . DOCDAT E OSWER/EP A I D DOCNUMBE R 3/1/1987_____EPA/600/S2-86/11 2 C077_____________________________________________________

_ TITL E CHEMICA L DESTRUCTIO N O F HALOGENATE D ALIPHATI C HYDROCARBONS . DOCDAT E OSWER/EP A I D DOCNUMBE R 6/23/1987____________________C014_____________________________________________________

_ TITL E INTERI M GUIDANC E O N COMPLIANC E WIT H APPLICABL E O R RELEVAN TAN D APPROPRIAT E REQUIREMENTS . DOCDAT E OSWER/EP A I D DOCNUMBE R 7/9/1987_____OSWE R #9234.0-0 5 C055____________________________________________________

_ TITL E COMPENDIU M O F TECHNOLOGIE S USE D I N TH E TREATMEN TO F HAZARDOU S WASTE S DOCDAT E OSWER/EP A I D DOCNUMBE R 9/1/1987_____EPA/625/8-87/014____2300_____________________________________________________

_ TITL E COMMENT S O N TH E PC B CONTAMINATION-REGULATOR YAN D POLIC YBACKGROUN D MEMO . DOCDAT E OSWER/EP A I D DOCNUMBE R 10/14/1987___________________C050____________________________________________________

_ TITL E PC B SEDIMEN TDECONTAMINATIO N PROCESSE S SELECTIO N FO R TES TAN D EVALUATIO N (TAKE N FRO M HAZARDOU S WAST E & HAZARDOU S MATERIALS , VOL . 5 , NUMBER , 3 , 1988) . DOCDAT E OSWER/EP A I D DOCNUMBE R 1/1/1988____________________C068____________________________________________________

_ TITL E APPLICATIO N O F INTERI M SEDIMEN TCRITERI AVALUE S A TSULLIVAN' S LEDG E SUPERFUN D SITE . DOCDAT E OSWER/EP A I D DOCNUMBE R 4/11/1988____________________C049_______________________________________________

_ TITL E COMMUNIT

YRELATION S I N SUPERFUND : AHANDBOO K(INTERI M VERSION) . INCLUDE S CHAPTE R 6 , DATE D 11/03/88 . DOCDAT E OSWER/EP A I D DOCNUMBE R 6/1/1988_____OSWER#9230.0-03 6 7000_______________________

_ TITL E SEDIMEN TQUALIT

YVALUE S REFINEMENT : 198 8 UPDAT E AN D EVALUATIO N O F PUGE TSOUN D AET . DOCDAT E OSWER/EP A I D DOCNUMBE R 9/1/1988____________________C095____________________________________________________

_ TITL E INTERI M FINA L GUIDANC E FO R CONDUCTIN G REMEDIA L INVESTIGATION S AN D FEASIBILIT YSTUDIE S UNDE R CERCLA . DOCDAT E OSWER/EP A I D DOCNUMBE R 10/1/198 8 OSWE R#9355.3-0 1 200 2

Thursday , Januar

y20 , 200 5 Pag e 2

### GUIDANC E DOCUMENTS

ER Aguidanc e document s mayb e reviewe d a t th e ER ARegio n I Superfun d Record s Cente ri n Boston , Massachusetts . TITL E BASI C EXTRACTIV E SLUDG E TREATMEN T(B.E.S.T. ) DEMONSTRATE D AVAILABL E TECHNOLOGY . DOCDAT E OSWER/EPAI D DOCNUMBE R 12/16/1988___________________COOS_______________________________________________________

_ TITL E LAN D DISPOSA L RESTRICTIONS . SUMMARYO F REQUIREMENTS . DOCDAT E OSWER/EP A I D DOCNUMBE R 6/1/1989_____OS-520__________C123______________________________________________________

_ TITL E SUPPLEMENTA L RIS KASSESSMEN TGUIDANC E FO R TH E SUPERFUN D PROGRAM . DRAFTFINAL . DOCDAT E OSWER/EP A I D DOCNUMBE R 6/1/1989_____EP A901/5-89-001____C104_______________________________________________________

_ TITL E GUIDANC E O N REMEDIA L ACTION S FO R SUPERFUN D SITE S WIT H PC B CONTAMINATION . DOCDAT E OSWER/EP A I D DOCNUMBE R 8/1/1990_____OSWE R #9355.4-0 1 2014_______________________________________________________

_ TITL E GUID E O N REMEDIA L ACTION S A TSUPERFUN D SITE S WIT H PC B CONTAMINATION . QUIC KREFERENC E FAC TSHEET . DOCDAT E OSWER/EP A I D DOCNUMBE R 8/1/1990_____OSWE R #9355.4-0 1 F S C254______________________________________________________

_ TITL E GROUNDWATE R US E AN D VALU E DETERMINATIO N GUIDANCE . ARESOURCE-BASE D APPROAC H T O DECISIO N MAKING . FINA L DRAFT . DOCDAT E OSWER/EP A I D DOCNUMBE R 4/3/199 6 C27 3

Thursday , Januar

y20 , 200 5 Pag e 3