) 151991 '- *

SUBSURFACE \ RELIMINARY ASSESSMENc^SSMENTT

ERA PROJECT 190043

Prepared For LEHMAN SUNOCO

B* EARTH RESOURCE ASSOCIA* 335 South Eighth Street Lebanon, Pennsylvania 1.. (717) 272-2177

tfully .ubmitted: Respec

~" Thompso8 P n* * Geologist 0043.RPT fage rfl

INTRODUCTION

In respons n Octobea , 199o t e17 r 0 lette re Pennsylvani th fro f o m a Department of Environmental Resources (DER) an assessment of hydrocarbon contamination associated with leakag unleadef eo d gasoline fro a formem r underground storage tank (UST thein )o r propertn i y Lehman, Pennsylvania, Lehman Sunoco contracted Earth Resource Associates, Inc. (ERA). The following report has been prepared by ERA n behalo , f Lehmao f n Sunoco o present , l findinge al t th f o s required assessment. Specifically addressed by the report are:

o Background information including site locatiod an n setting; soils; geology; hydrogeology; circumstances concernin e discoverth ge th f o y leaking UST; and, a review of available information concerning a prior hydrocarbon release at a former gasoline station located on an adjacent property.

o Procedures use instalo t d networa l eighf k) ^p (8 t shallow gr,QUndwate.fvi^monJ.^o^jing^^oints 4#*° *A« unconsolj_dated 'aqtjife d procedurean r s useo t d collect groundwater samples from these points.

o Procedures used to collect groundwater samples from the existing, on-site leak detection monitoring wells whic beed hha n previously installe Lehman di n both the old UST field and the new UST field*

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Procedures use colleco dt t groundwater samples from Lehman Sunoco 's on -site bedrock drinking vater suppl frod yan m fj^yJs.^(S) "nearby bedrock domestic: drinking water supply wells.

o Procedures use colleco t d surfacta e water sample fro a smalm l pond located east-southease th f o t ^ Sunoco Station.

o Analytical resultl surfacal groundwated f o san e r samples collected. '

SITE LOCATION AND SETTING

-*, I'Lehman Sunoco operates a gasoline service station and garage on an .{approximately i-acre site, alon soute gth h sid Statf eo en i Rout 8 e11 * .. ' ... rthe Tow f Lehmanno , Lehman Township, Luzerne County, Pennsylvania - • » -" * H> properte $ (FigurTh . situates 1) ei y "thet da " head "6"f *smala l northeast '•OilS^aa^trending valley, which vas artificially backfilled prior to i^ - , u constructio statioe th f 1959n o ni . Becaus topographie th f eo c relief of the area, the fill area drops off quickly in the form of steep embankment n botso e eas th ht 'and sout he stationsideth f o s , before merging wit naturale hth , gentl moderatelyo yt , eastward sloping land surface. Elevations range from approximately 1,300 feet above mean sea level (AMSL) in the vicinity of the station to approximately 1,275

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;et AMSL in the vicinity of the small pond and area located ,. >proximately 500 feet east of the station.

Surface Drainage

3 the site is situated immediately eaat-of- a .majorrregiohal^aurface" ater drainage. divJLde_i surface drainage from the property is in an easterl nortlieastlo t y y direction, with most flow dischargina o gt ;etland area and snail pond. This wetland area forms the headwaters of in unnamed to The Huntsville Reservoir. Flow from the reservoir is southeast to Huntsville Creek, which flows into » which in. turn flows into the just south of Kingston, PA. 0 Cultural Setting

The Lehman Sunoco site is situated in a rural- village setting, with much of the surrounding area consisting of farmland, open undeveloped [land, forested land, private residences , and small commercial J facilities. To the North, the site is bordered by several small 1 commercial and residential properties, one of which used to be a Sinclair- gasoline service station; to the East, the isite^ia bordered ,-• ^t-t* ...-..-..-. 'primaril undevelopey yb d scrub-shrub fores wetlandsd tan Wese th t , o ;t 7 the site is bordered by residential properties; . and to the South, by 7 open grass covered fields* residential properties, and forested land. i .. f - 5 .

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Procedures use colleco dt t tfroundvater samples from

V Lehman Sunoc s oon-sit' e bedrock drinking water suppl frod yan m JfiX£,.f,5J "nearby T bedrock\domcstic: drinking water supply wells.

o Procedures use colleco t d a surfact e water sample fro snaia m l pond located east-southease th f o t Sunoc' o Station.

o Analytical resultl surfacal d £roundwatef o san e r samples collected.

SITE LOCATIO D SETTINNAN L G t - '. - • - • : • i••Lehma: n Sunoco operates a gasoline service station and garage on an japproximately |-acre site, along the south side of State Route 118 in fthI e Town of Lehman, Lehman Township, Luzerne County, Pennsylvania ) (Figure 1). The property is situated at the" head "o'f"a. small northeast " ' ' •-••:- valley, which was artificially backfilled prior to 'constructio statioe th f n1959o n n i * Becaus topographie th f eo c relief . : •'"•'•• - : -•I ' of the area, the fill area drops off quickly in the form of steep embankments on both the east and south sides of the station, before merging wit naturale hth , gentl o moderatelyt y , eastward sloping land surface. Elevations range from^approximately 1,300 feet above mean sea level (AMSL) in the vicinity'of the station to approximately 1,275

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the earth's surface. The matrix material containing the coarse rock fragments usually ranges from clayey to sandy; however, overall textur dependens i e t upopercentage nth coarsf eo e fragmentsa s a d ,an result n rangca i e from claye o stonyt y n thiI .s portio f Luzerno n e County equal amounts of clay, silt, and sand normally comprise the matrix* The color of Olean till is strongly dependent on local bedroc rangn k ca typ ed ean fro m yellowis h5/6R Y brow reddiso )0 t (1 n h R 4/4)browY 5 .( n Lateral differences base n coloro d , matrix composition, and pebble content are also common (Growl and Sevon, r 1980).

In additio tilo t n l deposits, other type unconsolidatef so d sediments whicaree exisy th ahma n i tinclud e various sand, mixture gravelf so , pts*t, clad alluviayan l deposits.

Bedrock Geology

Bedrock underlying the Lehman Sunoco site has been mapped by the f Pennsylvania Topographi d Geologian c c Surve * the^Deyorii'aa y n aged c*,*iyAL^.Fprmation (Figure 3) (Hollowell and Koester, 1975) * The Catskill Formatio complea s ni x unit consistin darf go k grayiso t d hre reddish brown shale, claystone siltstoned ,an ; greenish gradard yan k grayish red, fine to medium "grained sandstone; and yellowish to . •*-*•.•*•"*•••«••———..- ". . ———^•^.__———«.- - • - •• **..!. .

I greenish gray* medium to coarse grained sandstone and conglomerate. it. ? Small amounts of grayish brown calcareous conglomerate and greenish gray conglomeritic mudston n alsca eo occur. Siltstone predominates within the lower portion of the Catskill clastic suite and quartz is tne predominant minera thin i l s formation e rocTh k. colo d graian r n

EARTH RESOURCE ASSOCIATES, INC. ARIQ0006 lunlley Mtn. Formotion

BBS i•JTTP^^f?^^ * ' ' *- «™KIKKK " Formation BS

— LEHMAN SUKOCO Hydrocarbon Contamination Assessment *• L

size alternate frequentl a typica n i y l e sectioCatakilth d an s ni l believed to be approximately 8,000 feet thick. Both the thickness and the abundance of red beds decrease in a westward direction (Hollowell and Koester, 1975)*

Sedimentary features common in the sandstone and conglomerate units include crossbedding, channeling, and cut and fill features, with fossils also common. The shale portion of the Catskill Formation disintegrates rapidly when exposed to moisture, weathering to small, platy, triangular fragments; while the sandstone, siltstone, and conglomerate units are moderately resistant to weathering and weather to medium and large-sized blocks* The mantle created by weathering is thickes n glaciatei t df variablo area d an s e thickness elsewhere. Surface drainage is moderate to good for unglaciated portions of the Catskill and poor in glaciated regions (Geyer and Wilshusen, 1982).

Bedding in the Catskill Formation is generally non-distinct in the shale, claystone, and siltstone units, but is well developed in the sandston conglomeratd ean e units. Bedding thickness ranges from less than one foot in the finer-grained units to between 10 and 16 feet in the coarser-grained units.

Bedrock Structure • * The trend"(strike) of bedr.ock in-this. region generally ranges between N.40'E. and N.50*E. and the (inclination) dip of these bedrock units range s degree5 e 2 southeasbetwee th d o an t s 1 nnorthwestr to e .Th . -ike of the bedrock was measured by ERA on an outcrop adjacent to the site and found to range from N;.39aE..; to^N.SS'E; The dip of the

EARTH RESOURCE ASSOCIATES, INC. ARIQQQQfl 90043 T .RP Pag8 #1 e • • " rocd _i k expose y thib d s outcro s e shallowfounb pwa o t d , ranging from 9* to 12* to the northwest. Based on these measurements, it appears as e situate b e northwes e sity th ith f ma e n o d t flana smal f o kl anticlinal form. ' , ; .

Rupture deformation has produced joints, faults, and certain types of cleavage in all rock units of the Catskill Formation; however, joints are the most common type of fracture observed in this formation. The most common jointing is associated with the stresses which accompany folding and faulting. In addition, loading of sediments can produce fracturing in brittle units sandwiched between more ductile units. In the Catskill Formation, brittle sandstone beds, with interbedded shale and siltatone, were subjected to differential stress during sediment iding and unloading, as a result of associated with the advance and retreat of glacial ice. Jointing in the Catskill Formation is well developed and moderately abundant, with the joints being closely space d regulashale an d th d siltston ean n i r e unitsd ,an moderately spaced and regular in the sandstone and conglomerate units. In most places, these joints for platma blockr yo y pattern opene ,ar , e steeplar d an yi dippin r vertical.o g . Chemical perclpitates, sucs a h * calcium carbonate e founb n d ,ca along joint face n thesi s e fractured r ' • , areas. In this region* joints typically .exhibit two (2) preferred orientations, with one. striking. N.IO'E* .and the second striking nearly east-west. A third and fourth joint set are occasionally present but --•('._- • are usually not as well developed (Hollowell and Koester, 1975).

observe nearba n o d measure yA an d outcroER y b d p revealed joints that were regularly spaced nearla d ;ha y vertical dip; were

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; d smootm Aidha »d plana han r joint surfaces. Thre ) prominen(3 e t .nt sets were found to be present in this outcrop* The first set has strike ranging between N.20*E.rand N,30*E., with a dip ranging tween 82'NW and. strika 90* s e seconha e Th . t rangin dse g between ranginp 15*W di N.20*W.d an .a g d betweean , n ST'NE^'and90e Th *. lird set, which is not prominent, has a strike ranging from N.75*W, \ > N.35'W., and a dip ranging between 80"ME and 90'.

Fracture Traces

racture traces and lineaments are natural linear features visible on lerial photograph s definee e surfacb whic th n s hca a d e expressionf so ligh angle fractures present withi e underlyinth n g rock* Because groundwater d moveoccuran n si s through these fracture zones, their locacion and orientation is important. According to Lattman (1958), fracture traces consist of variable topographic, ve£j&&AiJLanal, or s^ soil-tonal alignments that are primarily visible on aerial photographs e expressear d an d continuousl r lesfo ys than one- -mile, while lineament expressee sar d either continuousl discontinuouslr yo t a r yfo least one mile. Fracture traces do not include linear features that are related to bedding, striation, foliation, and stratigraphic contacts; but are related to individual joints, zones of closely spaced joints, or small scale faults* The most prominent fracture r . trace orientation observe thin i d s regio N.lO'Bis i n secona d ,an d preferred orientation trends roughly east-west. From these measurements it is evident that the preferred orientation of fracture trace jointd s an essentiall e sar samee yth .

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* flecture trace analysis was completed for the site by ERA to letermine preferential groundwater flow directions and to identify >otential contaminant migration pathways withi e bedrocth n k mass. 'his was accomplished by examining several aerial photographs of afferent vintages coverin e siteth g . This analysis showed fiv) (5 e poorly defined fracture traces in the vicinity of the site* Two (2) af these traces strike approximately N^3*W., while the other three (3) strike approximately 'Jf,\5§jJWVj which agrees quite well with regional fracture trace measurements previously mentioned* Fracture traces are poorly defined in much of this area due to the abundancejof surficial glacial materials deposited on top of the bedrock. Figure 4 is a map of the area graphically showing structural measurements (joints and ' Iding) and fracture traces in the vicinity of the site.

HYDROGEOLOGY

Groundwate n Luzerni r e County occurs under both Water table (unconfined) and artesian (confined) conditions. Water table condition those sar whicn i e h groundwate unconfines i r uppee th rd an d surfac watee th s fre I f reo o ris t e r fall o e . Arfesi'an^conditibns exist wheretthe groundwate confines ri permeable-formatioa n i d n that is overlain by a relatively impermeable formation* The upper surface is not free to rise or fall, and the water is under enough pressure to rise abov containine eth g aquife welln i r s that penetrate Th . it e Wr-ginary surfac whico t e h water will ris welln i e s tappinn a g artesian aquife calles i r potentiometrie th d c surface (Newport, 1977).

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Tne occurrence and movement of groundwatf r^is in and through interconnected openings whic e eithear h r primar r secondaro y n i y nature. Primary opening e voidar s s betwee e individuath n l grainf so material, such as in sandstone and shale. In a coarse-grained sandston openinge th e e relativelar s y largea shal e grain I th e. n size openingd san e versar y small e largeTh . r interconnected openings allow more groundwater movemen e smallet th tha o d nr ones. Secondary openings are those formed after the deposition and consolidation of the formations* In Luzerne County they result from the fracture or solutio rocf consisnd o kan Jointsf to , faults, cleavage solutiod ,an n cavitie e aquiferTh s. n Luzerni s e Count e composear y f boto d h unconsolidated formation d consolidatean s d rock formationsn I .

' . . "^consolidate(• d aquifers e wateth , r occur n pori s e e spaceth f o s unconsolidated material n consolidatei d an ; d bedrock aquiferse th , water occurs primarily withi e fracturesth n , bedding planesd an , solution cavitie e roc a th lessek o f t o smass rd degrean , porn i e e spaces between the individual mineral grains. Wells drilled into either type of aquifer will yield water if they intersect saturated i " . 5= • ' , ,,- - openings, althoug e greateth h e numbee saturate th rth d siz an f ro e d openings penetrated highee ,th re yield th wil e .lb

Unconsolidated Aquifer

The primary unconsolidated deposit within the vicinity of the Lehman Sunoco site is unstratified drift or glacial till. Groundwater within the unstratified sediments is confined to the interstitial area etween individual grains of sediment, and in general, yields little water to wells because of the presence of clay and silt* This fine-

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grained material reduce e por th e siz eth f so espace d retardan s e th s flo f wateo w r throug e formationw permeabilitth hlo e Th . f theso y e unstratified deposits results in steeply sloping and localized cones of depression and slow recovery of water levels in wells tapping these materials.

Well yields in Luzerne County unstratified drift sediments typically range from less tha 1 gallon r minutpe n e (gpm0 gpm1 o t ,) witn a h average yield of less than 3 gpm. Well depths typically range from 5 feet to 90 feet. Also, in unconsolidated formations of this type, & significant saturated thicknes s normalli s y necessar o develot y a p good well, and most high yielding wells are thought to penetrate some stratified unconsolidated materials. Based on observations made by ERA during drilling and sampling activities within the shallow aquifer e believw i e thae overalth t l permeabilit f thio y s aquifes i r moderatel o moderatet w lo y , although some gravelly layers exist which probably provide discrete zone f increaseo s d permeability. However, the lateral extent of these gravel zones is not known. In addition, occurrence baseth n o d nearbf eo y bedrock outcrop d nearbsan y domestic well information t doet i appea, no s r tha a significant t thicknesf o s saturated unconsolidated material occurs in the immediate vicinity of the site; however, this cannot presently be confirmed. It is likely that suatainabl eo permi t yield w tlo sclassificatioo coulto e b d f o n this zone as a true aquifer.

The quality of water derived from unstratified deposits in Luzerne County contains very little dissolved mineral matter, is very soft, and generally of good quality;'however, shallow aquifers of this type

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.•e highly susceptible to near surface pollution sources (Newport. 977). Base n surfaco d e drainage patterne topographith d an s c osition of the site, generalized groundwater flow within the shallow roundwater system beneath the site is believed to in an •asterly direction toward adjacene sth t pond/wetland area,

Bedrock Aquifer

Groundwater within the Catskill Formation is found in both the primary and secondary openings within the formation. The size and shape of the primary and secondary openings which occur between the grains differ wite degreth h f sortine originao e th f o g l materia d witan l h the amoun f cementatioo t n that bind e grainth s s together* Where _y trials are finer grained and well cemented, water moves primarily 1 : ,-•••' through secondary openings such as Joints, cleavage, and bedding planes. '•"•.-'

Within Luzerne County the(depth bedrocf o s k wells completee th n i d Catskill Formation typically range 0 feetfro 58 4 fee 2 m,o t wit a h i . ; ' median well depth of 160 feet. Well yields range from 2 to 325 gpm, with the median yield being 12 gpm. Normally, if a yield of 25 gpm or greater is desired, the well depth must be greater than 200 feet (Newport, 1977). _ ; « Tabl providee1 s some general informatio bedrocr nfo ke wellth n i s vicinity of the site and Figure 5 shows the location of these wells with s Importan i respece site t th I . o o not t t Tabln i e tha, e1 t - ' • ' 'ells 500, 499, 1009, 1010 d 153 ,havl an 5al e recorded water levels tha highee bedrockf o ar t p rto tha.e th nThes e records suggest that

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TABLE 1

Summary of Available Well Construction Information for Bedrock Supply Wells Near the Lehman Sunoco Site

DER TOTAL DEPTO T H DEPTH OF DEPTO T H VEIL KU DEPTH BEDROCK CASING KBZ's YIELD VATEft BEDROCK ID OVNER IFT) (FT) (FT) (FT) (CPU) IFT! AQUIFER

500 Coolbaugh 176' 78' 80' tio' 30 45' CatSkill 170' (Sandstone)

sot Krupsha US' 3' 21' 87' 26 48' Catskill 140' (Shale)

502 Cosgrove tH1 5V 21' 35' 25 57' Catskill 107* (Shale)

505 Martin 221' 23' 24' 85' 10 130' Catskill 215' (Sandstone)

499 Coolbaugh JO1. 34' 26 19' Catskill 102' IP (Sandstone) 156' 667 Hozeapa 206' 41' 43' 168' 9 « Catskill 204' (Sandstone)

1009 Sholtes 185' 75' 92* 165' 15 40' Catskill

1010 RoRanchick 225' 78' 95' 125' 12 50' Catskill 280*

1535 Sutton 225* 75' 118' 150' 15 35' Catskill 200' (Sandstone)

GPU - Gallons Per Hinuti KBZ's - Hater Bearing Zones SOURCE: Pennsylvania Geologic Survey Hater Veil Inventory Database.

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W fa /7^,*'-"*'^

the bedrock aquifer in the vicinity of these wells and possibly the sit s artesian.ani e d exhibit a positivs e head, which would help protect the deep bedrock aquifer from near surface contamination.

Groundwater derived froe Catskilth m l Formatio s generalli n f gooo y d quality d hardnesan , d dissolvean s d solid e lowar s. Occasionally, salt wateproblea s i r thin i m s formation d irod manganes,an an n n ca e also exceed EPA recommended drinking water standards.

Because of an inability to access most wells in the vicinity of the o theit site e r du ; burial below grade, having structures built over them, or not being able to obtain permission from their respective owner o chect t possibls no ks themo wa definitivelt e t i ; y establish e directioh f groundwateo n r flow withi e bedrocth n k underlyine th g site. However, deep groundwater flow beneat e siteth h , which wile b l influenced by fracture patterns and other structural components of the bedrock e topographi th wels ,a s a l c positio e sitth e f wito n h respect to regional drainage systems expectes i , east-southeaste b o t d .

OCCURRENCE OP HYDROCARBON CONTAMINATION AT LEHMAN SUNOCO

Ori-Sitc USTs

During the Fall of 1990, Lehman Sunoco initiated a routine upgrade of undergroune th d gasoline storage tanks locate theit a d r facilityt A . . tha, •. t time, Lehman Sunoco became aware that some leakag d apparentleha y occurre their of r) dUSTs(1 d frothae an ,on m t this releasd ha e resulted in some contamination of the underlying soils. In order to

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^ ' that analysis confirmed that the contaminating material was gasoline, I" 41 which matches the petroleum oil fingerprint completed for a sample collected froe shalloth m w unconsolidated aquifer, intercepteI y b d r well SW-1.

SUMMARY OF FINDINGS

e findingBaseth n o d dresult an s f thio s s assessments ha A ER , -J* determine e followingth d :

e LehmaTh o n Sunoco Sit s situatei e e th n i d Appalachian Mountain e SectioValleth d f an yo n Ridge Physiographic Province, whic generalls i h y characterized by flat-topped mountains and hills thae dissectear t y steep-sideb d d stream valleys. However e are, th muca f o surroundinh e sitth ge exhibit a shummock y appearanc e a resul th s a ef o t glaciation that occurred during the Pleistocene geologic time period. This glaciation has also produced erratic surface drainage patterns/ numerous lakes d numerouan , s wetlande th n i s vicinity of the site.

e sit Th situates i e o d Just majoa eas f o tr regional surface water drainage divide surfacd an , e water drainage froa the site is to the east-northeast, with most flow dischargin unnamee th o t gd adjacent ' &RIOOOI8 EARTH RESOURCE ASSOCIATES, INC" .M 90043.RPT Page #80

9f r pond/wetland Ae Ar located approximatel 0 fea50 y t east of the station. This pond/wetland area forms the headwaters for a small stream that empties Into the Huntsville Reservoir. Eventual discharge from the Huntsvllle e SusquehannReservoith o t s i ra River near Kingstont PA.

o Soils observed by ERA during the drilling of eight ) shallo(8 w monitoring points consistef o d yellowish brown, light brown, medium brown, brownish yellow, reddish brown, and grayish brown, gravelly silt 1oa o mgravellt y loam. Also,

i occasional thin layer siltf so y clay were observed a fragipa d an s evidenwa n somn i t e boring a ' t S* a s . • j-*U , depth of 2 to 3 feet. The gravel seemed to occur in distinct layers and increased with depth. In addition, the amount,of gravel appeared to increase towards the pond. Soil texture ranged from tightly wH compacted to loose, and no consistent horizontal or l t vertical relationships were eviden n soili t s underlyin s determineha site e A th gER .d basen do

L - ~f . P I " : ' available mapping naturae th ^ l soils underlyine gth site belong to the Oquaga and Lords town series, the Wellsboro series, and the Chippewa series, n additioI ° naturao t n l soil I rS s underlyin sitee th g , statioe th n are underlais i a artificiay b nW ; I1 * l fill • ' ' " ' material, consisting primaril f reddiso y h 'brown

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shaly fill,, large angular rip-rapd an , miscellaneous debris (vood, concrete, etc.)e Th . exact thicknes d configuratiosan f thino s fill unit is not known; however, based on visual observations A believeER , o rangt t ei s from -less tha 0 feetfoo1 n 2 betweeo t td . an 5 n1 e LehmaTh no Sunoco Sit s underlaii e y botb n h glacially formed unconsolidated material and consolidated bedrock units, witunconsolidatee th h d material overlying bedrock in all locations on~ site.

onle Th y onatura l unconsolidated deposit observey db e on-sitb o t s glacia wa eA ER l till,e whicth s i h material in which the site's soils have formed. On-site glacial til s primarill wa observe A ER yy b d yellowish brown, although some reddish browd an n reddish gray till were also observed. The till matrix appeared to contain equal amounts of clay, silt, and sand; however, intervals did occur which were predominantly sand or clay. The coarse fraction content varied acros e sitt th sbu e appeare o increast d e with dept d towardan h e th s pond/wetland area, and consisted of pebble-sand to coarse gravel-sized sandston d shalan e e fragments whic e angulaar h o subroundedt r A believeER . e th s aRiooozo 90043. RPT Page #82

thickness of this glacial till unit may range from feet5 1 o .t 5 ] o Bedrock1 underlyin e sits beeth gha e n e mappeth y b d Pennsylvania. Topographic and Geologic Survey as the \ Devonian-Aged Catskill Formation, which is a 1 complex unit consisting of dark grayish red to reddish brown shale, claystone, and silts tone; 1 greenish grad daryan k grayish red, fin mediuo t e m grained sandstone; and yellowish to greenish gray, J mediu o t coarsm e grained sandstond an e 1 conglomerate. t encountereBedrocno s A wa ER k y b d during the on -site drilling operations; however, on available well construction information for nearby wells, and the pressure of bedrock -I outcrop e vicinit th e site A th n believei s ER t f o y s depte th bedroco t h k range s1 from approximatel3 y ^ feet8 7 fee o .t

~i o Bedrock structural measurements taken by ERA near site th e shoe strik th w. . f beddineo g1 ranging from ff.39*E. to N.SS'E. with dips ranging from 9* to 12* 3' - - . Incline northweste th o t d . Thre ) prominen(3 e t Joint sets were also evident in local outcrops. *5 The first set exhibited a strike ranging between V e th o N.20*Et * d N.30*E82 an . f o .p witdi a h northwest to 90* (vertical). The second set had a § . strike ranging between N,15'W. and N.20*W. with a fl R i o n n ? i fl EARTH RESOURCE ASSOCIATES, INC. H" I UUU-C I 90043.UPT Page #83

dip of 87' to the northeast to 90'. The third set, prominentS A t a strikwhicno d s i ha hte ranging between N.75*Wo t ' d N.85'W.80 an f o .p witdi a h the northeast to 90'• These measurements agree well with regional measurements obtainee th r fo d are othersy b a .

A fractur o e trace analysie th sr completefo A ER y b d sitd surroundinan e g vicinity showed fiv) (5 e poorly defined fracture traces occurrine th n i g vicinity of the site. (Fracture traces are surface expressions of high angle fractures in the i underlying rock d alonan t g with bedrock structuret can influence preferential groundwater flow directions withi bedroce th nf o k) mass.(2 o Tw ) these traces strike approximately N.3'W.t while the other three strike approximately N.85'W, These measurements also agree quite well with regional fracture trace measurements.

A shallo o w groundwater flow syste presens e i m th n i t unconsolidatcd material beneath the site. Depth to groundwater in the unconsolidated aquifer ranges from near surface in the wetland area to approximatel e vicinite th th n i f 1 feeo yy1 S BG t Sunoco Station. The average depth to groundwater in the unconsolidated aquifer across most of the site is 3 to 5 feet BGS; howevert it appears flRI0002that 2 90043.RPT Pag4 #8 e

this water table fluctuate a goos d deale Th . direction of groundwater flow in the unconsolidated aquife re east-northeas th beneat o t e sit s th hi e t with discharge to the pond/wetland area. No water supply well e presentlsar y know o exist n n thii t s shallow groundwater system.

o Base n observationo d A sdurin ER mad y gb e drilling • ' - . r and sampling activitie shalloe th n i sw aquifere w , believe the overall permeability of this aquifer is moderately low to moderate, although gravel layers exist which probably provide more permeable zones for fluid flow. Xn addition, it does not*appear tha a significant t thicknes f saturateo s d unconsolidated material occurs in the immediate s likeli vicinitt i e sitey th d tha an ,f o yt sustainable yields could be too low to permit classificatio thif no s zona "true s ea " aquifer.

, . , . . .^ . . : o Groundtfater flow withi Catskile th n l Formatios i n

, •' : -.-:'" • '- \- - • ' foun botn primarde i th h secondard yan y openingf so the formation. Where materials are finer grained and well cemented, groundwater will move primarily

- ± through secondary openings suc Jointss ha , cleavage planes d bedding,an . possiblt Althoughno s wa e t i , to definitively establish the direction of groundttater flow in the bedrock, based on fracture patterns And the topographic position of the site

EARTH RESOURCE ASSOCIATES, INC. fl R I 0 0 0 2 3 90043.RPT Page #85

with respec o regionat t l drainage systems, groundwater flow withi e bedrocth n s expectei k o t d be eas o southeastt t . Groundwater qualite th n i y Catskill Formation is usually good, and many wells e Catskil e vicinitth ie a sitth np th s ta e a l f o y source of potable water supply.

o Base n welo d l construction informatio d statian n c water level information attained from well permit forms for wells in the vicinity of the site, it is prob&ble that the bedrock aquifer in this area is positiva artesias ha d e nan head f trueI . , this would help protect the'bedrock aquifer from near surface contamination.

o During a routine upgrading of their underground storag eFale tankf 1990th o l n i s , Lehman Sunoco bec&ne aware that some leakag d apparentlha e y occurred from one of the gasoline tanks and that some; contaminated soil was present. All contaminated soil which could be excavated from the are withoua| t causing structural damag tho t ee station buildin d adjacenan g t roadway s removewa , d and stockpiled on-site for later disposal. In addition, the leaking tank and three (3) other tanks which showed no indication of leakage were removew tankne d s dan wer e installed.

EARTH RESOURCE ASSOCIATES, INC.RRI00021* . 90043. RPT Page #86

o Monitoring wells installed in the old underground storage tank excavation and the new underground storage excavation have been periodically monitored by station personnel smaj.d ,an 1 amount gasolinf so e gasolind an e vapors have been detected A wate. r sample collecte Sunocrot e f dth a o Statio watea n' r supply well showe BTEo n d X compound d onlan sa y small amount of TPH (16,05 mg/1 ) .

o During investigatio Lehmae th f nno Sunoco SiteA ,BR became aware of another nearby -underground storage tank problem. Accordin boto gt h local citizend san DER leakina , g underground storage tanremoves kwa d approximately thre ) year (3 froo e sag formea m r • . j • • • t Sinclair Service Station which was located Just north of the Lehman Sunoco Station. Rfe understand that soils were contaminate gasoliny db thad ean t a / shallow well owned by Ms. Elda Coolbaugh was also contaminated by gasoline, and required replacement.

SARTH RESOURCE ASSOCIATES, 0002I INC p « . 5 90043.RPT Page #87

•—-f The Coolbaugh well WAS located between the former Sinclair pond/wetlane Statioth d an n d area.

o -A~total- of^eighteen- (18).groundwater and_ surface -.w'sLljer—samples were collected on-site and in the

vicinity of the Sunoco Station in order to assess** the impact--o e gasolinth f e leakage shalloth n o ew •*>^d»rii«*^

o Bedrock wells sampled by ERA in the vicinity of the site had essentially no BTEX compounds or TPH detected durin e Marc th g, 199 7 h 1 samplinge Th . 4 ug/1. 1 concentratio f tolueno n e observee th n i d

EARTH RESOURCE ASSOCIATES, Itfdl 0002RI 6 ' j90043.RP T Pag8 #8 e 1^ Sunoco Station supply well, and the 1.0 mg/1 I concentration of TPff observed in the Sunoco Station supply well ffosee th , y domestic well (DW-1)d ,an J the John's public non-community well (DW-4), are e laboratorth t a l yal detection :limit r thesfo s e • * t considereparameterno e ar d d an sIndicativ f o e I gasoline contaminatio bedroce th n ni k aquifer.

| o Shallow monitoring wells (MW-3, MW-4, and MV-5) T excavatioUS w installene t Lehmae a nth n ni d

t ; ( Sunoco were monitored for the presence of free- . phase gasoline prio samplingo t r free-phaso N . e ,- gasoline, hydrocarbon sheen, or hydrocarbon odor v^ f theswao sy enote an wellsn i d . However) (2 o ,tw . . , . ^ shallow monitoring welld sol (MW-e MW-2d th an 1n )i I UST excavation, both of which contained no water, 1 did exhibit strong gasoline odors in the well a casinhydrocarbo d an g ne electri sheeth n o n c ] water tape probe. o Onl y fivf ) shalloo thre (5 e) 1 (3 e w monitoring wells (MW-3, MW-4, and MW-5) contained water for sampling J on March 7, 1991. Veils MW-3 and MW-5 had no BTEX compounds detected H concentrationTP . MW-n i s 3 • wer Kg/15 ewerdetected ( t veran - w )eno MW ylo n di IS. Veil MW-4 displayed a small concentration of ^ - ' ' *••'.-'' xylene (21.9 ug/1) and a small concentration of TPH I (2 mg/1). No BTE was detected in Mff-4. These ¥ ARIOQ027 J , EARTH RESOURCE ASSOCIATES, INC. 90043.RPT Page #89

concentrations do not appear to indicate a significant gasoline contamination problem in the new tan A- field area. The lack of higher BTEX and H concentratioTP n thesi n e wells also suggests that the spill which occurred during installation of the new tanks was of limited areal extent*

o The presence of a hydrocarbon sheen and strong ) monitoringasolin(2 o tw e eg th odo welln i rn i s the old tank field area, indicates the presence of gasoline constituent e soil d th probabl an sn i s y shallow groundwate n thii r s area. This remaining contaminatio s mosi n t likely associated with soils that could not be excavated from beneath the Sunoco Station and the roadway adjacent to the old -UST field e becauspotentiath f o r eseriou fo l s strvctural damage.

o Shallow well points (SW-1 through SW-8) installed by ERA in a downgradient direction from the Sunoco Station were monitored for the presence of free- phase gasoline prio samplingo t r . Well point SW-7 contained some highly weathered free-phase gasoline and emulsified hydrocarbons and well point SW-1 contained traces of free-phase gasoline. e highesTh to concentration f totao s l BTEX compounds in the shallow groundwater were detected in SW-1

EARTH RESOURCE ASSOCIATES, INC. fl10002R 8 90043.RPT Pag0 #9 e

(105,917 ug/1), located northwes pone th d f neao t r Route 118 SW-d an , 7 (136,095 ug/1), located Immediately vest of the pond/wetland area. Significantly lower stilt bu , l elevated total BTEX concentrations, were also detecte n Sff-i d 2 (452 ug/1), SW-3 (73.4 ug/1), SW-4 (3,729 - ug/1)SW d ,an 5 (23,840 ug/1) o significanN . t total BTEX concentrations were detected in 5V-5 or SW-8.

The general distribution of benzene in shallow groundwater was similar to that for total BTEX. e greTh a test benzene concentrations were founn i d 5*r-i (20,480 ug/1 )SV-9 5 (4,403 ug/1)d ,an (43,591 ug/1). Other shallow well points where benzene was detected include SW-2 (27.8 ug/1) and SW-4 (71,7 ug/1) benzeno N . detectes wa e SV-n i d S or SK~3, and only 1.0 ug/1 was detected in $W-6.

o The general distribution of toluene in shallow groundwate similas rwa o thar t totar fo t l BTEX. e greatesTh t toluene concentrations were founn i d SW-1 (48,013 ug/1), Sif-$- dO',197 ug/1) Sff-d ,an 7 (65,546 ug/1). Other shallow well points where toluene was detected include SW-2 (208 ug/1) and SV-4 (1,145 ug/1). No toluene was detected in 3, SW-6, and

EARTH RESOURCE ASSOCIATES9 , 2 INC0 Q .Q I ftR 90043.RPT Pag1 #9 e

generae Th lo distributio ethylbenzenf o n shallon i e w groundwater was similar to that for total BTEX. The greatest ethjrlbenzene concentrations were found in SW-1 (4,274 ug/1), SW-5 (985 ug/1) SW-d an , 7 (3,105 ug/1). Other shallow well points exhibiting ethylbenzene include SW-2 (15.2 ug/1 SW-d )an 4 (300 ug/1) ethylbenzeno N . detectes ewa SW-3n di , SW-6, and SW-8.

o The general distribution of xylene in shallow groundwate S similaWA r o thar t totar fo t l BTEX. The greatest xylene concentrations were detected in SW-1 (33,150 ug/1), SW-5 (8,255 ug/1) SW-d an , 7 (23,853 ug/ . 1) Othe r shallow well points exhibiting xylene include SW-2 (201 ug/1), SW-3 (73.4 ug/l) SW-d an t4 (2,213 ug/1) xyleno N .s ewa detected in SW-6 or SW-8. e highesTh o t concentration H withiTP e f th o ns shallow groundwater system were detecte n SW-i d 1 (101 mg/1), SW-2 (40 mg/1), and SW-7 (4,191 ntg/1). Other shallow weJJ points displaying detectablH TP e concentrations include SW- 1 mg/1)( 3 , SW-5 4( ng/1), SW-5 (2 mg/1), and SW-8 (4 mg/1). No TPH detectes wa Sv-6n di .

o A surface water sample collected from the pond/wetland area exhibited a total BTEX

EARTH RESOURCE ASSOCIATES, INC. fl R I 0 0-0 3 0 90043.RPT Pag2 *9 e

~ concentratio f 88,55o n 0 ug/1, whic comprises wa h d 19 of 19,505 ug/1 of benzene, 44,301 ug/1 of toluene, *^i 6 ug/1, 74 f ethylbenzeneo 1 d 22,99an , $ ug/1f o J - H concentratioTP xylene e Th . f thio n s sampls wa e gl 16 mg/1.

samples) collecte) (2 (1 o e Tw ,on d o from SW-d 1 an M collecte) on(1 e d fropond/wetlane th m d areaa d ,ha | lf petroleu l fingerprinoi m s ChromatograpGa t h analysis conducted to determine the nature of the JJJ contaminating material. In both samples, the ^g, contaminating materia s determinewa l e b o t d ^-^ gasoline.

analyticae Th o l result shallof o s ^ w groundwated an r -*i surface water sampling suggest that a significant portioe shalloth f o nw unconsolidated aquifer jn downgradient from the Lehman Sunoco Station, and the surface water ,into whic t ultimateli h y ^* discharges, have been significantly contaminated by •ft gasoline. Based on the results of this preliminary assessment, yree'ls'e'" lateral - or vertical' extent^ of 2 ~£hj:.s m__gasolinis__ ^contamination-^ -wl^th'ln -—the tuiicorisolfdated aquife knownt no s r.i "^«J1 . o measuree Baseth n do d "directio groundwatef o n r flow ' : • • . . V withi e unconsolidateth n d aquifer appeart i , s that « eithe Lehmae th r n Sunoco Station, a whic s ha h HRI0003I 90043. RPT ] Pag3 #9 e RECEIVED j

documented release formee th r ro , Sinclair Service station, which also has had a documented release, could have contribute e gasolinth o t de il contamination problem. ERA', believes -7i t_U is .*•"*••• *. i j £.- - probabJe .that bqth .stations ^have contributee th o ^t problem.

e lateraTh o l distributio e gasolinth f o ne constituents withi e unconsolidateth n d aquifes i r somewhat uneve d doe pinpoint nan sno specifie on t c source area. This uneven distributio f higd o n an h w concentrationlo s coul e affecteb de th y b d heterogeneous e unconsolidatenaturth f o e d formation, the presence of a multiple source, the occurrenc f differeno e t timed releases froa m single source or a multiple source, well spacingf r shalloo w water table fluctuations.

o sampline Baseth n do g resultsix^(6)^nearbf o r fo s y bedrock water supply wells e bedrock,_&quiferth , « :dpes-inot_appear to have been impacted to date by gasoline releases from the former leaky underground storage tanks. It is possible that the bedrock aquifer in the vicinity of the site is" artesian, which would—protec t to*somi t e .degree from near surface contamination. It is also possible that the presenc shalloa f eo w unconsolidated aquifer Rl*0nn^9 predominately comprised of unstratified materials 90043.RPT Page #<

and considerable Amounts of fine-grained sediments abov bedroce th e k aquifer offere ddegrea f o e protectio bedroce th r e kfo th n Aquifeo t e du r e constituennaturth f o e t organic compounds composin gasoline gth e contaminant.

REFERENCES

Bush . DennisR , t a.1e , , 1973, Soil Surve f Luzerno y e County ISL* Pennsylvania! U.S. *Dept f Agriculturo . e Soil Conservation • Service.-•<• .

Crowl, Q.H W.Dd .an . Sevon, 1980, Glacial Border Deposit f Latso e Wisconsina Northeastern I e Ag n n Pennsylvania, Commonwealtf o h Pennsylvania! Dept Environmentaf .o l Resources.

Hollowell, Harrd Jerralan Koester. y. E R d , 1975, Ground-Water Resources of Lackawanha County, Commonwealth of Pennsylvania! Dept Environmentaf .o l Resources.

Geyer, Alan R. and . J. Peter Wilshusen, 1982, Engineering ; '. • .... «. Characteristic Rocke th Pennsylvaniaf so f o s , Commonwealtf o h Pennsylvania, Dept. of Environmental Resources,

Lattnan, L.H., 1958, Techniqu Mappinf eo g Geologic Fracturd an e Lineament n Aeriao s l Photographs, Photogrammetric Eng., v.42, no 4, p. 568-576. fiR!00033