SU P ERFUND SIT E C L O SE OUT REPO RT JACKSON STEEL S U P E RFUN D S I TE VILLA GE O F MINEOL A NASSA U COU N T Y, N EW YO R K I. I NTRODUCTION The 

# u.s. Envir onme n tal Pro te c tion Ag e ncy (E P A) has determi ned that all appropriate re s po nse actions f o r the Jac k s on S teel Superfu n d site have bee n successfully implemented i n a c c o rdance with Clo se Out P roc edure s f or Na ti onal Prior i t ies L ist Sites ( OSWER Directive 9320
. 2

- 22 , May 2011 ). Specifical ly, based upon fie l d observ atio ns as so c iate d with EPA oversight and the results o f a final inspection of the s i te o n July 13 , 20 16 , i t h a s been determined that the remedy has been implemented i n accordance w ith the 2004 Reco rd o f Decision (ROD ), as modified b y 2 00 7 and 2016 Explanations of Significant Differen ces (E S Ds)
. It has bee n determined that no further res p o n se, other than the continued op eration o f vapor intrusion mitigation s y stems at 

## a day c are center located adjacent to the former Jackson S tee l building, institutional controls ( ICs ) v erific atio n and five

- year reviews , is antic i pated. Human exposures and contaminated ground w ater rel eas es are under contr o l
. II. SUMMARY OF SITE COND I T I O N S Site Background The 1.5-acre site contains a one-sto ry, 43 , 000- s qu are - foot buildi ng formerl y used as a metal

forming facil i ty and an ap p roximate ly 10,0 0 0 -s quare foot p aved parking area. T he site is bordered to the north by commercial and sin g le -family dw el li ngs , to the east by a two - story apartmen t co mpl ex , to the so u th b y a day c are ce n ter , and to the we s t by an off ic e building and restau r an t . The property w as used b y Jackson S tee l I n c . f r o m the mid

- 1 9 7 0 s until 1991 as a "roll form metal shapes" manufacturing f acili ty . D eg reas er s , including tetrach l oroethylene ( PCE ), trichloroeth y lene ( TC E) and 1, 1 , I -tric hlor oeth an e (I, 1 , 1

- TCA), were u s ed at the facility until 1985. Sludges from de greas i ng equipme n t w ere s to red in drum s and in an o n - property 275-gallon tank. The anal ytical result s from samples c oll ec te d by the N ass au County Dep artment of He alth ( NCHD ) in the earl y 1 990s from within , ar o u n d , and below thre e on - pro p erty dry wells i ndicated the presence of PCE , TCE, 1 ,1, I -TCA , 1, 2-dic hl o ro e thy le ne (I, 2- DCE) and 1,1

- dichloroethane (I , l-DCA ) at depths do w n to 40 feet be l o w th e gr ound surface. PCE , TCE , l ,l, l

- TCA , 1, 2

- DCE and 1 ,I -DCA w ere also detected i n gro un d w ater s amp les coll ected from mon i toring wel l s l ocated downgradient of the dry w e lls
.2

The contamination f

o un d at the site was likely c au sed by the discharge of wastes into the dry w e lls, an d spi ll s and le ak s f

rom drums containing vari o u s chemicals during Jackson Steel ' s operation s. T he site w as l isted on EPA's Superf und Nation al Priorities List on February 4,2000. F oll owing th e commencement of the remedi al investigation ( RI) in October 2001, NCHD performed air sampling inside the day care cen ter's building because of its proximity to the site . The air samples detected PCE at levels belo w the New York State Department of Health' s (N YSDOH's ) guide l ine for indoor PCE exposure . Given the sensitivity of the population expo sed (p reschool children ), NCHD collected addition al samples in December 2001. At that time, indoor testing was al so c on ducte d i nside the Jackson S te el building and at the restaurant located adjacent t o th e site. T h e resu l ts i ndicated that PCE l eve l s in the indoor air of several rooms in the day care c enter were abo v e NYSDOH's guideline for P CE
. l As a result, in January 2002, a sub s lab depressurizati on system ( i
. e . , vapor intrusion mi ti gation system) wa s installed by EP A
. In addi tion, a v enti l ation s y stem w as instal led b y the day care c enter's contractor . Samples collected to assess the effec tiveness of the imp l emented measures showed that the PCE levels in the air were significan tly be l o w NYSDOH's guideline and b elow EPA's acceptable noncancer risk level s . Becausee l e v ate d PCE levels were also detecte d i n a billiards club that shared common walls with the site bu il ding an d the
. day care center , EPA i n s talled a vapor intrusion mitigation system under th e c oncrete slab of

thi s building, as w el l
. The b il liards c lub was subsequently occupied as a re tail st ore , an d recen tly the daycare center expan d e d to occupy this space . The vapor intru s ion mitigati on s yste ms w ere replaced b y the property owner ' s contractor in May 2016
. Remedial Investi ga tion and Feasibility Study R esults The resu l ts o f th e RI , w h i c h w as completed i n 2 002 , indicated that volatile organic compounds ( V OCs ) , semi

- vo l atile organic compounds (S VO C), pesticides and metals contamination were present in the surface soil and VOC contaminati o n was present at several subsurface soil locations. In addition , con t amination was found in a trench an d sumps located inside the building and dry wells lo c ated under th e parking l ot at the site. Gr ou n d wate r f

rom th e three hydrogeolog i c uni ts underl y ing the site

- the Upper Glacial Aquif er (u pper aquifer ), Mago thy Confining Bed ( a low p ermeability, clay layer separating the upp er and d eep aquifers ) , and the Magothy Aquifer ( deep a quifer)

- w ere also sampled. VOC contamin ation above state an d federal standards was detected b oth in the Upper Glacial Aquifer and Magothy Aqu ifer
. Based upon th e res ult s o f the RI, a base l ine hum an health risk assessment (HHRA ) was conducted to e v al uate the po tential for current and future i mpacts of site

- related contaminants on receptors using the site. U nder baseline conditions , the hu man health risks posed by the groundwater and th e s u rface soil at the site, as well as the contaminants on the floor of the on-property building,

1 NY SD OH ' s g u i d e lin e at that time w as 100 micro g rams pe r cubic meter (ug/nr' ) ; the current guideline is 3 0 u g/ rrr'
.

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were fou n d to b e unacceptab l e . Cancer ri s k s e x c e e ding the ri s k range were identified for a future adult inside i n du strial w orker ( 7.9 x 10- 3 ) , 2 fu ture a dult outsid e industrial worker (7.3 x 1 0

- 3 ) and future adult

/c h ild resident (2. 5 x 10 -2 )
. Th e p ri mary c ontributor to the s e risks was exposure to the g r ound w ater . Noncan cer hazards e x ceedin g the h a zard index (H I )3 were identified for the future adult inside i ndustri al w orker ( HI of 30 ), f u ture adu l t outside i ndu strial worker (HI of 23) , future adult resident ( HI of 5 1) and futu re chil d resid ent ( HI o f 158). Th e pri mary con tributor to these His was expos ure t o the g round w ater . A scre e ning of eco l ogical ri s ks w as perform e d
. B e c ause th e property includes a mos tly paved industrial/co mmercial f ac il ity, there is mi n i m al h abitat available for ecological receptors on th e property. Due t o the suburban/commerc i al se tti n g , the pote ntial for exposure to receptors and ecological ri sk is min i mal in th e area su rr o un din g the property a s well
. Record of Decision F i ndings Following the comp l etio n of the reme dial inv e sti g ati on/feasibility study ( RI l FS ), on September 24 , 2004 , EPA selected a rem e dy for the si te i n a R O D
. The RO D outl i ned the following remedial action objectiv es (RAOs ):

• minimize or eliminate c o ntaminant mi g r ati o n from contami nated soi l s and dry wells to th e groundwater ;
• mi n imize or el i minate any contamin ant mi gr ati o n from con taminated so i ls and groundwater to i ndoo r air;

• restore g r oundwater to l evels which meet st ate and federal s t andards within a rea s onab l e time frame ;
• mitigate the migration of the affecte d g rou n d water; and

2 Cance r ri sk is expressed as a p r obability . F or e x amp l e , a 10

- 4 c an ce r risk represents a "one in 10 , 000 excess cancer risk ," or an increased risk of an i n d i vi du al developin g can c er o f one in 10,000 as a re s ult o f exposure to Site contaminants u n der the con di tions u se d i n th e Ex pos ure As s e ss ment . Under the federal Superfund program, as o u tl i ned in the NCP , E PA ' s g o al o f p r otection i s an exces s canc e r risk of 1 0

- 6 or less for the RME i nd i vidual. The NC P acceptab le canc e r ri s k range is 10

- 4 to 10

- 6 ( corresponding to one i n 10 , 000 to one i n 1 ,0 0 0 , 000 e x cess can ce r ri sk)
.
3 The potenti al for noncancer heal th effec ts i s ev alu ate d b y compari n g an e xpo s ure level over a specified time peri od (e
. g . , 7 y ears or more) w ith a re feren c e d o s e ( R ID) derived for a similar exposure pe ri o d
. An RID rep rese n ts a l e v el th at an in d i vi dual may be e x p o se d t o that is not e xpecte d to cau s e any adverse effects
. The ratio of e x posure to t ox icity is e x press e d a s a Ha zard Quotient (HQ)
. An HQ le s s than 1 i s not of concern . An i ll represents the s um o f th e ind ivi dual h azard quotient s for different chemicals and d i fferen t media
. A non cancer i ll of less than 1 is not o f con c ern .4

• reduce or eliminate any di re ct co n ta ct , i n gesti o n , or i nh alati o n threat a ssociated with contaminated soils, soil vapor, contami n ated surf a ce s i n th e o n - p r op erty building, and groundwater
. The s elected rem e dy includ e d th e followin g acti o ns:

• decontaminati o n of the Jackson Ste e l buildi ng floor;

• in-situ soil vapor extraction (ISVE)4 to tre at the contami nated s ub s urface s oil i n on-property source areas ; • excavation and off

- site disposal of the co nt aminate d s urface soil an d co n tami nated material in on - site sumps , a trench, and dry w e ll s c o ntaminated wi th VOC s , S VO Cs , metals , and pesticides;

• in

- situ chemical oxidation 5 to treat the c o n t aminated gro u n dwater in the Up per G l ac i al Aquifer;
• extraction and treatment of the contamin ate d gro undw ater in th e d eep a quif er if con f

irmatory groundwater s ampling indicate s that th e s i te i s a p rincipal so u rce of the groundwater contamination to the aqu i fer underlying the si te;
• if it is determined that the si te is a p ri ncipal sou rc e of th e gro u nd w ater c o n tamination to the deep aquifer underlying the site , the sel e cte d re medy would be expanded, as necessary , t o include off

- property groundwater contaminati o n ; and

• l ong - term groundwater monitoring
. At the time of the ROD, the daycare center and b il liards cl ub bu il dings w ere uno ccupied , so the ROD indicated that if these buildings were reoc c u pie d, mon itoring t o ass u re that no u nacceptable v apor exposure takes place would be in s tituted , an d the ven ti l ati o n s y s tems in s t all e d du ring the Rl would be operated and appropriately maintain e d. The soil cleanup objectives were est ablish e d pu r suant to N e w Y ork State Tec hnical and Admini s trative Guidance Memorandum (TA GM) No. 94

- HWR- 40 46 obj ectiv es ( Di v ision Technical and Administrativ e Gu i dance M emo r an dum: D e terminati on of So il Cl eanup O bjecti v es and Cleanup Levels , Division of Hazardous Was te Re mediati o n , J anuary 24, 1994)
. Th es e l eve l s were the more stringent cleanup level b e tween a hu m an-he alth p r o te c ti on value and a v al ue based on protection of groundwater . Th e groundwater c l e anup goal s w ere the more stringent of the s t ate or federal promu l gated standards.

4 ISVE involves drawing air throu g h a series of w e l ls t o v o latiliz e th e so lv en t s i n the s oil s. T he extracted vapors are then treated
. 5 Un der this techno l og y , an oxidizing agent i s inj e c te d in t o the co n t aminate d groundwater. A n ox idizing agent uses oxygen to degrade VOCs
.5

Reme dial A ctiv itie s Pe rfo rm e d Bu ildi ng Decontamination The design spe ci f

ic ations for the bu il ding d eco n t aminati o n w ere compl e ted by EP A' s c ontr ac t or , .

. CH2MHill , in Oc t ober 200 5. T he buil d in g decon t amin atio n w as performe d by E n vironmental Was te Minimi zati o n , In c . ( EWM I )
. Of

f i ce e quip me nt and con s truction m aterial w ere remo v ed fr o m the interior o f the Jac k so n Stee l bui l ding on Oct o ber 15 , 2005
. T h e cleanup of the buildi ng floor comme n ced o n January 6 , 2 0 0 6. Broo m s w eepi ng an d pre ss ure w a shing w as used to remo v e res i dual w aste . O n c e the initial c le aning was comp l ete , the b ui l din g f l o o r wa s de co nt aminated using a floor scrub ber . All ri nse w ater w as col lecte d using s ho p v a cuu m s and sto red in 55

- gal lon drums . So l i d deb ri s was also sto red in separate 55-gall on dru ms . In t o tal, 10 drums of ri nse w ater waste and 18 dru ms of so l id w aste w ere tran s p o rte d t o a n onhazardo u s waste faci l ity for di sp o s al
. Soil E x c avatio n a nd D isposal The design s p ecificati o ns for th e soi l ex c avatio n w ere completed in Octo b er 2005
. The e x cav ati on an d di s pos al o f th e co nt ami n ated surface soi l, the contami nated materi al in th e bu i lding sumps and tre nch , and th e con taminate d material in the dry we ll s w as performed f rom October 2005 to February 20 0 6. C&Z C o n stru c ti o n , Inc ., perfo rm e d the excavation of the surface soil along the eastern b ou n dary o f the s i te . EWM I perf ormed the excav ati on and rem ov al o f so il from all other areas and the remo v al and di s p o s al of the contami nated materials from th e sumps and the tre n ch inside th e bui l di ng , and f ro m the dry wel l s . A tot al of 170 c ubic y ards of material was e x cav ated and di sposed of at an EP A

- app r o v e d off

- site facility. The anal y ti cal resu lt s f r o m po st-e xcav ation s o il s amples c ollected from the excavati on l imits i ndicate d th at the residu al l e v e ls ofV O C s were b e l o w the ROD soil cleanu p objecti v es . In-Situ So i l Vapo r E

xtractio n ISVE w a s impl eme n te d in two p h ase s , a Pha s e 1 p ilot test, and Pha s e 2 f ul l -scal e imple m e nt ati o n . The design specifications fo r the Pha s e 1 and Ph a s e 2 ISVE were completed i n February 20 0 5 and May 2005 , respective ly. The pi l ot tes t w as conducted i n M arc h 2 005 to e v al uate the effectiv e ness ofISVE i n treati ng VOCs in the subsurface soi l and so i l gas at the site an d to e s t ablish th e design parameters fo r the f ull

scale s y stem . The pi l ot tes t, w hich was imple m e nte d by CH2MHill , c ons i sted of the in st all ation of four I SV E w e l ls an d eight v apo r monitorin g probes
. Sin c e the resul t s of thi s test sh o w e d promise , the f

u l l-scale s y stem ISVE sy s tem w a s c o n structed in July 2005
. This inc l u d ed the i nstallation o f a total of fi v e additional I SV E we l l s an d three a dditio nal vapor monitoring probes. The co v er age area i nc l uded a section o f th e p arki ng lot and the s ecti on of the bui l ding where historic sou rces w ere lo cated
. A ll of the pr o c e s s e quipment , excep t the g r anular acti v ated c arb o n6

( GAC ) vessels , were housed in an insulated, ful l y enc l osed trailer
. The trailer an d the GAC vessels w ere lo cate d in s i de ofthe J ackson Stee l building
. A dischar ge vent was install ed along the outside w all o f th e building
. Pip in g i n si d e th e buildin g w as install ed abo v e grade on the concrete floor s lab
. Th e vacuum blow er o perate d t o re mov e m ore than 1,0 0 0 cubic feet per minute of vapor from the sub s urface and main tain e d a net negativ e pres s u re i n the subsu rface whi l e operati ng. Th e ISVE s y s tem operate d f rom 2 00 5

- 2 00 8. B ased o n the resu l ts of the soi l gas sampling, it wa s d e te rmined that the oper ati o n o f the I SVE s y stem ha d met the ROD soi l c leanup objectives. Althou g h th e s oil cleanup obj ec tiv es w ere m et , b ecause v apors con tinued to b e recovered , it was decided that the ISVE sy stem would continue t o oper ate until the v apors w ere reduced to levels that ach i ev e d the remedial action obj ec ti ve o f mi n imizing o r eliminating migration to indoor air
. Based on the continued vapo r re covery by the IS V E sy s tem and the persiste n t el evated levels of PCE and TCE in soil gas s ampl e s collecte d fr o m be low th e c oncrete s l ab o f the Jackson Steel building , from J anuary 24 , 201 2 to February 1 5 ,2 0 12 , a M e mbrane I nterfa ce Pro b e ( MIP ) and soil samplin g investigation was p erform e d to d e l ine ate the l ateral and v ertical extent of PCE and TCE in the so ils a s a potential sourc e of so il ga s con c e ntrations
. T he MIP tec h n ology i denti f ied three potential shallow subsurfa ce (2 to 6 fe e t b el o w g r ade ) ho t spots w here c o n f irm at ory soi l samples were collected using conv en tion al drilling an d s oi l samplin g methods. Det ail s re l ate d to this effort are des c ribed in the "Monit orin g R es ul ts " se c ti on, b el o w . Based on the res u lts o f the MIP investi gation and confirmato ry s oil samples , e nhan c ements were made t o the ISVE system . Sp e cifi c ally, in June 201 2 , ni ne n ew v apor e x tr a ction w e l ls w ere install ed in the three discrete hotspot area s in s ide the buildin g . E PA continue d t o operate the ISVE system u nti l June 12 , 2013, when the levels of vapor re mov al were determi ne d t o be too l ow f or the s y ste m t o continu e to be effectiv e . The I SVE system , which oper ated for a tot al o f 5 5,8 7 1 hou rs , rem ov e d an e sti m ate d 8 3 po u nds of VOCs from the subsurface
. The ISVE system was decommi ss ioned in Ap ri l 2016. In-Situ Chemical Oxidation The design specifications for th e in

- situ che mi c al o xid ation (I SC O) s y s tem were co mp l eted in June 2005. Redox T ech , LLC, wa s s ub c o ntracte d to p erf orm the I S CO o peration in the Upper G l acial Aquifer
. A bench-scale study was performed in Marc h 2 0 0 5 to evaluate and se l ec t th e ox idant media and dosa ge to be used in th e inj e ctions
. A n i mple m e ntatio n p lan detailing the des i gn o fthe injection system, injection location s , an d s pecific quantiti es of o xidant to b e u se d wa s p repare d in June 200 5. Between July and D e c emb er 200 5 , appr o x i mate ly 1 5 , 000 gallons of ir on-catal yzed sodium per s ulf ate (with small amoun ts of buff eri n g ag en ts ) an d 60 0 gallons o f h ydr o gen peroxide were injected in the aquifer through a n etwork o f 2 0 in j e c ti on w e ll s .7

Oxidation wi th Inje c te d Air Upon review of the post-chemical o x idatio n i nje c tion d at a , it wa s determined that the concentrations of several con t aminants h ad s li g h tl y rebounded af ter a significant initial drop
. As a polish i ng step , air oxidati on was implemen ted i n o rder to fu rth er reduc e the VOC concentrations
. The design specifications for the air oxidatio n s y ste m were d e v elope d in May 2006 by CH2MHill
. The air injection system operated from Ju n e 7 t o 2 6 , 2 006 and Aug u s t 18 to Sep te mber 15,2006
. Vapor Int rusion Mitigati o n After i ssuan c e of the ROD i n 2004 , the v acate d n e i g hboring building s where vapor intrusion concerns had p reviousl y been identified were re - o cc upied by a d ay c are center and a retail store. At present , both buildings are occu p ied by th e d aycare center . The vapor i n trusion mitig ation systems that were installed by EP A operate d u nti l M ay 2016 , w h en the syste ms were replaced with new systems by the property owner ' s con tractor. Remedial Ac ti on Repo rt s and P relimina ry Close-Out Report The Upper G l acial Aquifer remedy was determi ned to be o per atio n al and fu nc ti onal with the approval of a Remedial Action Report on Sep te mber 2 9,2006
. A Re medial Action Report was approved on September 30 , 2008 , documentin g th e co mpleti on o f th e b u ilding d e c on tamination and the determination that the soil excav ation an d I S VE s y stem h ad m et the cl eanu p obj e ctives for the soil. A Preliminary Close-Out Report was ap p ro v ed on Au gust 3 0, 2007. 

### III. MONITORING RESULTS In-Situ Vapor Ext r

actio n Syste m As was noted in the " Remedial Activities Perform e d " s ection, ab o v e , b as ed on th e c o ntinu e d vapo r recovery by the ISVE system and the persistent e l ev ated l e v e l s ofPC E an d TCE in s o i l ga s s amples collected from below the concrete slab of the J a ckson Ste e l b ui l di ng , a MIP an d s o il sampling investigation was performed. I n general, th e c o mpari s on of so il boring log o b servations , soil analytical results and MIP logs showed a general c oncu rre nc e . T h e s oil sample' s analytic al results showed PCE ranging in concentration from 0
. 0 0 5 1 to 14 m g/ kg ( the R O D s oi l c l eanu p obj e ctive is 1.4 mg/kg ) in soils j ust beneath the floor of th e building and TCE c o nc e ntr ati o ns ranging from
" not detected " to 0.0 1 6 mg l kg ( the ROD soi l cl e anu p o bje c tiv e i s 0.7 mg/kg )
. The MIP technology identified three potential shallow subs urface h o t s pots wh ere co nfirm atory so i l sampl e s were collected using con v e n tional drilling and soi l s amp l ing method s. As was note d above , based on the results of the MIP investigation and con f irm atory so i l s amp l es , enh ancements were made to the ISVE system. Upper Glaci a l A quife r M oni tori ng Prior to the remediation of the Upper G l acial A qu if er , c is- l, 2-DC E was dete cted at a maximum8

con c entr ation of 340 mic r o g ram s per liter ( u g/l) and PCE w as de tecte d at a maximum concentration of 63 jlg/l (th e Maximum Contami nant L e v e l s [MCLs] f or ci s- l, 2-DCE an d PCE are both 5 ug/l )
. Nine rounds of Upper Glacial Aquifer post
- ch e mi c al oxid atio n in j ec ti o n gro undw ater performance sampl i n g ( October 2005 thr ough Augu s t 200 6 ) w ere c ondu cted
. Upon re v ie w of the post-chemical oxidation injection data, it w a s noted that the c o n c en tration s o f se v eral co ntami n an ts had slightly rebounded after a significant initi al drop
. A s a p ol is hing s tep , ai r oxidation w a s imp l emented in order to further reduce the VOC concentration s . Groundw ater samp les c oll e c te d in March 2010 only showed cis

- l,2

- DCA marginally exceedin g the MCL at 5. 6 u g/l. D uring the f i n al s ampling event in September 2011, the only contaminant d etected wa s PC E at 1. 3 ug/l , Deep Aquifer Investig a tion A supplemental groundwater investigation w a s c o n du cted f r o m Marc h 20 0 5 t o Sep tember 2006 to d etermine th e so u rce of the Magothy Aquifer co nt amination undern eath th e Jackso n S tee l Si te and to establ i sh whether there is a relationship betw e e n the c o n tamin atio n at th e Site and the VOC contamination detected in Vill a ge of Mineola S u p p ly Well #4
. As p art of this i n v estigation , six monitoring wells were installed
. Three wells w ere installed i n the M agothy Conf ining Bed at the l ocation ofthe on - site dry wells where the dump in g of chemi c als occ u rre d
. Thre e a d diti onal wells were in s talled off

- site into the Magothy Aquif er ( at app r ox imate l y 455 f eet )
. O ne w e ll is l ocated approximatel y 300 feet northw e st of the si te . T h is w e ll i s considered u p g radien t u nder regional flo w conditi o ns and s i degradient when Villa g e o f Mineol a S u pp ly Well #4 i s pu mping. The second monitoring well is locate d southwest o f the site
. T h i s well is c onsi dered downgradient u nder regional flow conditions and sidegr a di e n t when V i ll age of M in e ola Supply We ll #4 is pumping
. The third well is located between th e s ite and Vi l lage o f M i n e ola S u p ply W ell #4 , approximately 1,20 0 feet southeast of the s ite . T h i s well i s cons id ere d si d e gradi e nt under regional flow conditions and downgradi e nt when Vill ag e o f Mineola Supp ly We ll #4 i s pu mping
. The results of the investigation, which are s u mm ari ze d in the Su pp lemental Gro undwater Invest iga t ion, CH2MHill , October 2 006, an d Findings of the Sup p lemental Gro undw a te r Inves t igati on, EP A, Septemb er 2006, indic ate th at multipl e so u rc es ap pear to co ntri b u te to the contaminati on in the Mago thy Aquifer undern e ath the site . B a se d on the i n ves ti gation , i t was concluded that the s ite is n ot a current so u rc e of con taminati o n in th e Ma gothy Aquifer
. Therefore, EP A decided not t o impl e ment th e M a g othy Aqui fer g rou nd w ater remedy
. An ESD was i s sued on August 28 , 200 7 , documenting th i s decision
. Va por Intrusion Moni toring After issuance of the ROD in 2004, the v a cate d ne ighbori n g bu i ldi ngs where v apor i n tru sion concerns had pre v iously be e n identified were re - o c cupied by a daycare ce n ter and a retai l store. At pre s ent, both buildings are occupied by th e d aycare c enter . Th e existing v apor i ntrusio n mitigation systems are currently operating in th e o ccupied buildi n g.

### 9

The day care c en ter i s regu l ate d b y th e New Y o rk State O f fic e of Children and Fami ly S erv ices ( OCFS )
. O n Sep tember 8 , 20 0 9, the f ac ility e ntered into an agreement with OCFS such that i t would continue to a d dress vap or intru s i on as a c on di tion of maintaining its daycare center li cense . Annual subs lab and i n doo r ai r testi n g indicate s that w hi l e v apors are still present beneath the daycare center and J ackso n S teel bui l din gs, th e i n d oor air in the daycare ce n ter is in the acc eptab l e range ( the indoor air i s n ot sampled at the J ac k s o n Steel bui l ding a s it i s not occupied and man y o f the building ' s windo w s are not intac t)
. E P A d e termined that various ongoing/future vapor intrusion mitigation actions are neede d to pre v e n t current (i n the case of the occupied b u ilding ) and potential future ( in the case of the J ac ks on S te el property) ex po sures to VOCs inside occupied building , and that thes e actio n s w ill be nee ded u n ti l the subslab vapor leve l s final l y dissipate. A June 2016 ESD documents th is determin ation
. 

### IV. ATTAINMENT OF GRO U NDW A TER RE STORATION CLEANUP LEVELS Sampl i ng w as con duc ted in th e Up per G lacial A qu ifer fo l lo w ing th e comple tion of the air i n jecti on polishing in September 2006. Ground water s amples col l ected in March 2 010 only showed cis

I,2-DCA m arginall y e x ceed in g i t s MCL at 5. 6 u g/l
. Sampling conducted i n Septe mb er 2011 showed onl y PCE at 1
. 3 u g/l
. Samplin g i n the Up p er Glacial Aquifer was discontinued af ter this sampling e v en t . As is discussed abo v e , because it w a s con c l u ded that the site w as n o longer a so u rce of contamination in the M agoth y A quifer , ground w ater monitoring was suspended
. 

### V. OPERATION AND MA I NTENANCE No operatio n and mai ntenance ( O&M ) ac tivi tie s related to th e I S CO injecti on s were needed. O&M activities related to the ISVE s y stem and v apor mi tigation s ystems included :

• recording w ell flo w rates , vacuum rea din gs , an d s y s tem performan c e read i ngs
• collec tin g field s c reeni n g data at v ari ou s p o i nt s of the system
• record i ng vapo r monito rin g w ells and ISVE w el l s pressure re ading s
• col l ec ting sampl es from th e IS V E s y stem infl u e n t and effluent for laboratory anal y s i s fo r contami n an ts of co n cern t o assess the n e e d f o r G AC c hange

- o ut
• GAC change-outs

• annual subslab , subs lab vent , i ndoor ai r sampl es The abo v eground ISVE infrastructure w as re m o ve d by CH2MHill i n June 2013. From March 21 , 2016 to Ap ri l 19 , 20 16 , E arth Data Northe a s t, Inc
. remov e d three Westbay groundwater monit o ring w el l s y stems . During that perio d o f ti me , AARCO Environmental Services Corp. decommissioned 15 standard groun dw ater mon i to ri n g well s , 20 ISVE wells, 1 1 vapor monitoring wells , 20 ISCO injection wells and fi v e I SC O monitoring w e ll s. Each loc ation was restored 

### consistent wi th NYSD E C ' s decommiss i o ning p o l i c y .1 0

Althou g h EP A s uccessfu ll y re mediated the s oil and th e gro und water a quif er immediately u nd e rly ing the site, residual le v e ls o f VOC s re m ain. VOC s , ev en at l o w l e v e l s , c an migrate as v apors through the soil into building s . This p r o ce ss , which i s c al le d v ap or intru s io n , can result i n u nacceptable human exposures to VOCs in si d e o c cupied buildin g s . This p athw ay is c u rrently incomplete at the site, because the bui l ding on th e s ite is currently uno ccup ied an d subs l ab vapor intrusion mitigation systems prevent the mig r ati o n of vapor s int o an ad jac en t o c cup ied bu il ding. Because the residual l evels of VOCs are ex p e cte d to di ssi pate s lowly, E PA co nc lu ded that preventing human exposure to VOCs at the occ u p i ed buildin g will be needed for a number of y ears to ensure the protectivene s s of the remedy. Therefore, th e ex isti n g v apo r miti g ation systems wi ll nee d to conti nue t o operate and additional a c ti ons, from moni t ori ng to the in s t allation o f an add i tional v apor mitigation system, may be n e e d ed should the c u rre n tly u n o c cu pied bu i lding be occupi e d or rep l aced w ith another structure in th e future. EP A d e termin e d that ICs re qu i ring the continued operation o f subslab vapor intrusion mi tigation sy s tem s w ere n ee ded
. In a d di tion , EP A d etermined that I Cs requiring vapor intrusion s ampling and/or mitig ative mea s ures w ere neede d s hould the u noccupied building be occupied or replaced with another stru c ture in th e f u tu re. E P A al so determine d that a Vapor I ntrusion M an agement Plan (VIMP) to describe the n e c essary moni t oring and mainte n ance a s sociated w ith the e xi s ting and any future vapor intru si o n mitigati on s y stems , and an I nstitutional Control Implem e n t ation and As s uranc e Plan (ICIAP) , to i dentify a p rocess and sche dul e by which the I Cs w o u l d be implemente d and maintained, s houl d be dev e lo ped for the site . EP A issued an ESD o n June 20 , 2016 , docu me nting its determination to incorpo rate into the remedy ICs to pre v ent exposure through v apor i n tru s ion , to remain in place until th e res idu al VOCs f ull y dissipate i n the subsurface
. The ESD al s o n o ted th at a V IMP an d ICIAP w o u ld be prepared to e nsure that the IC s w ere appropriate ly imple m e nte d and maintained
. In addition, th e E SD n ote d th at EP A w ou l d c o mmunicate direc tly w ith the V illage of Mi ne o l a Sup erin te ndent of Bu il dings , requ esting that EPA and NYSDEC be notified i f th e existing building i s to be refurbi s he d an d used fo r human o c c u p anc y or demolished and a new s tructure con s truc ted
. The correspond e n ce w oul d al s o requ est th at th e Village not issue a Certific ate of Occupancy until necessary vapor i n tru s i o n re l ated a ctio ns i de n tified b y EP A and NYSDEC are carried out . A VIM P an d ICI A P were completed on June 2 0 , 20 1 6. On Ju ne 2 0 , 2 01 6 , EPA sent a letter t o the V i llage of Mi n eola Sup erintendent of B uild ings , requ e s ting th at EPA and NYSDEC be notified i f th e existing building is to be refurb i s h e d an d use d for human oc cu panc y or demoli s hed and a new s tru c ture co ns tru c te d an d re que s ted the Vi ll age not i ssue a Certi f

icate o f O ccupancy until nece ssary v apor intru s ion

- related a c tions iden ti fied by EP A and NYSDEC are carried out . Periodic reminder s will be i ss u e d to the Village to h e l p e nsu re the e ffe ctive n ess o f this meas u re . Th e daycare c enter i s regulated by OCFS
. O n S epte mber 8, 2 009 , th e facility entere d i nto an ag re eme nt wi th O CFS such that it would conti nue to addres s vapor intrusion as a conditio n of maint ai ning it s d aycare c e nter l icense
.11

The record owner of the two parcels occupied by the daycare center (both parcels are covered by the same deed) signed a deed notice on June 23, 2016 , but could not notarize his signature. With his consent , a successor in title notice was placed on the deed of the property on July 27, 2016. The notice provides perpetual notice that the subslab vapor intrusion mitigation systems must be operated as long as elevated levels of vapors remain under the buildings and said buildi ngs are occupied. Because the owner of the Jackson Steel property is defunct , on July 27 , 2016 , a successor in title notice was placed on the deed of the property to alert any potential purchaser , lessee or other user of the property that EP A and NYSDEC must be notified if and when a determination is made that the existing building will be refurbished and used for human occupancy or demolished and a new structure constructed. EP A will effect an environmental easement on the Jackson Steel property in the future once a new owner takes contro l ofthe property.
VI. DEMONSTRATION OF QAlQC FROM CLEANUP ACTIVITIES RA activities at the site were undertaken in a manner cons i stent with the ROD (as modified by the ESDs) and the design specifications. All applicable EPA and State quality assurance and quality control (QA l QC) procedures and protocols were incorporated into the design specifications. EP A analytical methods were used for all validation and monitoring samples during all RA activities. All procedures and protocols followed for groundwater and soil sample collection and analyses during the RA are documented in the plans , specifications , and design reports and the sample analyses were performed at state-certified laboratories. The QA l QC program used throughout the groundwater and source contr ol RAs was rigorous and in conformance with EP A and State standards ; therefore , EP A and the State determined that all analytical results are accurate to the degree needed to assure satisfactory execution of the RAs, consistent with the 2004 ROD , as modified by the two ESDs , and the design plans and specifications.
VIII. FIVE-YEAR REVIEW The first five-year review , was completed in August 2012. The review concluded that the remedy was functioning as intended by the decision documents and was protecting human health and the environment. Subsequent to the 2012 five-year review , EPA determined that rcs were necessary to ensure the protectiveness of the remedy, as discussed above. Five-year reviews will be conducted as long as residual VOC levels remain that perpetuate the vapor intrusion concerns described above. The next five-year review will be conducted by August 2017.12



### IX. SITE COMPLETION CRITERIA The site meets all the completion requirements as speci f ied in OSWER Directive 9320.2-22 , Close-Out Procedures for National Priorities List Site s. Specifical l y, all areas of concern have been adequately addressed , the implemented remedy achieves the degree of cleanup specified in the ROD, as modified b y the two ESDs , for all pathways of exposure , and no f u rther Superfund response is needed to protect human heal th and the environment. The only continuing efforts at the site are the ongoing operation and maintenance of the vapor intrusion mitigation systems at the daycare center , periodic vapor intrusion monitoring , insuring that the institutional controls remain in place and effective and five-year reviews to ensure the remedy remains protective.

Approved: Walter E
. Mugdan , Director

Emergency and Remedial Response Di vi sion Date