United Sows
Environmental Protection
Agency
Office of
Emergency end
Remedial Response
6PA/ROD/R03-84/008
December 1984
Superfund
Record of Decision:
Tysons Dump Site, PA
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TYSON'S DUMP SITE, PA
Record of Decision
Abstract
The Tyson's Dump site is located in southeastern Pennsylvania,
approximately 15 miles northwest of Philadelphia. The dump is an
. abandoned septic and chemical waste disposal site which operated from
1960-1968. Unlined lagoons were filled with wastes and covered, and new
lagoons were created. Major contaminants found at the site were volatile
organic compounds, primarily xylenes, toluenes, and 1,2,3-trichloro-
propane. In addition, chlorinated benzene compounds were also detected.
The cost-effective remedial alternative selected for this site
includes excavation and off-site disposal of contaminated soils and
wastes; upgrading of the existing air-stripping facility to treat
leachate, shallow ground water, and surface run-on; and excavation and
off-site disposal of contaminated sediments within the tributary which
receives effluent from the existing air-stripping facility. The
estimated capital cost for the selected alternative is $5,718,000 and
operation and maintenance costs for five years are estimated to be
$351,000.
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). .
RECORD OF DECISION
REMEDIAL ALTERNATIVE SELEcrION
TYSON's DUMP $ITE. UPPER MERION TOWNSHIP. PENNSY LVAN IA
IXX:UMENTS REVIEWED'
---------------.--
I am basing my decision principally on the following documents
describing the analysis of cost effectiveness and teasibility ot remedial
alternatives for the Tyson's Dump Site~
Remedial Investigation Report (Draft) Tyson's Dump Site.
Montgomery County, Pennsylvania (Michael J. Baker, Jr., Engine8rs,
Inc., August 1984)
Feasibility Study Report (Dratt) Tyson's Dump Site. t-1ontganery
County, Pennsylvania (r1ichael J . Baker r Jr. r Engineers, Inc.."
August 1984)
Summary of Remedial Alternative Selection
Recamnendations by the Pennsylvania Departm8nt ot Environmental
Resources
DESCRIPI'ION OF SELECI'ED REMEDY:'
-----------..
Excavation and off-site disposal ot contaminated soils and wastes
to a pe~itted RCRA landfill.
Upgrading of existing air-stripping tacility to treat leacnate;
ground water, and surface run-on encounterea during excavation.
OPeration of this facility is projected to remain on-line until
residual ground water contamination is eliminatea (est. 5 yrs.)
shallo'w'
Excavation and off-site disposal of contaminated sedin~nts within the
tr'lbt~~ which receives effluent fran the existing air stripp:r:.
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-2-
DECLARATIONS -:
--- --.----.----
Consistent with the Comprehensive Environmental Response, Compensation
and Liability Act of 1980 (CERCIA). and the National Contingency Plan (4U
C.F.R. Part 300). I have determined that excavation and oft-site disposal
of contaminated material and upgrading the existing treatment tacility tor
continued treatment- of liquids collected trom the site is a cost-eftective
remedy which effectively mitigates and minimizes damag6 to and provi~es
adequate protection of public health, welfare, and the environment. The
remedial action will be designed to minbnize the risk ot potential evacuation
and temporary inconveniences to the local environment during the excavation
and transportation phases. .
The State of Pennsylvania has been consulted and agrees with the
approved remedy. Following excavation of contaminated soils and wastes trom
former lagoon areas, operation and maintenance activites will be r~uired
to ensure the continued effectiveness and level of protection ot tl~
remedy. These activities will be considered part ot the approved action
and eligible for Trust Fund monies tor a period ot one year.
In addition, the oft-site disposal of contamined soil and sediment
to a secure hazardous waste facility is necessary to protect public
health, welfare and the environment.
I am deterring selection of remedial response measures, if any: tor
the deep aquifer and floodplain/wetlands area. Additional stuaies will
be conducted in the off-site areas to deter.mine if ott-site remedial
action is required.
I have determined that the action being taken is appro~riate wh~n
balanced against the availability of ~st Fund monies tor use at otner
sites. tflh.fJ- .' ,~ -~_\.! ?Jll;JJ!:g(/l--
DATE {/ I . :; As(j{f{ant Admlnlstrator! t-
- I -
0fice of Solid Waste and ~rgency Response
J '
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SUMMARY OF REMEDIAL ALTERNATIVE SELECTION
-- -- - - ---- -- - ----... ----- - _._... ....- -...- - - - ---
TYSON'S DUMP SITE
- ---.- _. -- - - - - - - - -
SITE DESCRIPTION
------ -
Tyson's Dump site is an abandoned septic and chemical waste disl~sal sit~
situated within an old sandstone quarry. As shown in Figure L the sit~ is
located in southeastern Pennsylvania, 15 miles northwest ot Philaaelphia, in
Upper Merion Township, rrbntgcmery County. Several tormer unlin~ lagoons W't::re
used to store various industrial, municipal, and chemical wastt:s. Spills ana
overflows reportedly occurred during the period ot operation, thus allowing. tor
the dispersal of wastes throughout the site. Surtace water runott ana see~
also contributed to otf-site migration of the wastes northeasterly towaro the
floodplain of the Schuylkill River.
The four acre parcel canpris ing the former lagoons is boraered both to tIle
east and west by unnamed tributaries to the Schuylkill River, a steep quarry
highwall on the south, and a Conrail P..ailroad switching yard on the north (see
Figure 2). The Schuylkill River floodplain is on the opposite side of the t
switching yard. No structures exist within the old lagoon area and heavy /
vegetation obscures visual observation of contaminated areas. Vehicular access
to the site is fran Brownlie Road. An access road used during previous oUlut-i[1("j
operations runs along the northern portion of the site.
The major watercourse in the project area is the Schuyikill River. Tne
average discharge at a nearby upstream station is record~ to be: 1907 ~ubic
feet per second (cfs). Flood elevations in the vicinity of the sit~ are-
Flood FEegu~ncy
10 year
50 year
100 year
500 year'
~}.~yat:.~9.!1hJ tee~ above_~l-)
7U.5
77
80
87
Thus, over half of the area north of the railroad tracks is witr.in the 10
year floodplain, while most ot this are.a would be ininaated bY' a 5U year tlCXJd
and all of' it would be covered by the 100 year tlood. The site itselt lies
above the..IOO year floodplain. (See Figure 2).
Tyson's D.Imp site is located within the lower member of the SwcktoCl
geologic formation outcrop area. Soring logs indicated that most natural soils
appear to consist of a less than one foot thick layer ot topsoil which is
underlain to a depth of six to eight feet by clayey sand to sandy silt. This
layer generally is underlain by fine to medium slightly silty sand with same
gravel extending to a total depth of about 12 feet. Shallow bedrock in the
vIcinity of the site was observed to be highly fractured. A typical cross
section is included as Figure 3.
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BAStf MAP IS A POmON OF TX ULS.&S. NOIWISTDWN, PA QUADRANGLE (7.5 MINUTE SERIES, 19€«, PMOTQRCV1SED 1973)
COMTOUH INTERVAL. t to'.
FIGURE 1
LOCATION MAP
. "
TYSON'S DUMP.UPPgR MER10N TWP^ PA
SCALE' 1*32000'
. , 9
WATER
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Fig-ure2 ...-
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TYSON'S DUMP' SITE
u"la "1.'011 10.11'".'
11011160..1.' COUll". '11III"lv""IA ..
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~- - - -- -
APPROXIMATf lAGOC:
L.OCA nONS BASfD ON
AE~IAL PHOTOGRAPH i
'BUfR I T5A
1111111I0Il or IIICKAIL ..... coa'O."IIOII
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--- TOP OF BEDROCK
rn CLAYEY SAND TO SANDY SILT
~ WITH SOME GRAVEL
m fiNE 10 MEDIUM SAND WITH
ld SOME GRAVEL. SLIGHTLY IILTY
VERTICAL EXAG. IX
OLD
lAGOO~S l
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Itlb" "0 'EOROCK ~ "''''-c.._£»''''' "'I "c""'"'''''' ".." RlV£18
'lOS, ----L6. ... ~\.:.. , ,,~
lOWER STOCKTON ,... -- . ~""-4
100
200
500
400 500
DISTANCE IN FEET
800
700
. 800
TYSON'S
DUMP
SITE
GENERALIZE 0 GEOLOGIC
SECTION
200
150
100
50
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~
w
. ,
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Ground water underlying Tyson's Dump Site behaves as two hydraulically
connected aquifers. The shallow aquifer within the unconsolidated sediments
exhibits a different flow pattern than the deeper aquiter in the !ractured
bedrock zone. The shallow aquifer is characterized by high permeabili ties
while th~ deeper aquifer flow pattern (the major ground water aqui!er ot the
area) is controlled by the degree of fracturing and fractur~ orientation,' The
shallow aquifer discharges through the floodplain/wetlands area to the river.
The deeper aquifer is considered a Class II aquifer as defined in the dratt
Ground Water Protection Strat~ (GWPS). '
,
Land use in the vicinity of the abandoned disposal site~includes r~sidential,
cammerical and industrial. Immediately adjacent to the site on the western
border, is a newly develoPed residential subdivision. South ot the site is
zoned residential and agricultural while to the north, the zonir~ is heavy
industrial. The Upper Merion Township as a whole is experiencing rapia growth
with several new residential developments being recently completed or proposed.
It is expected that land zoned agricultural will be re-zoned tor high aensity
residential use. Norristown is a large residential, commercial and industrlal
area with a population of 3~.000 and is located across the Schuylkill ~iver, ap~roxi.
mately 1/2 mile northeast of the site. The smaller resid~ntial area uf Briagcport,
(population 4,900) is located approximately one mile east and aownstred~ ot the
site. Belmont Terrace, which contains several hundred single-tamily dwellings,
is located approximately 1/2 mile southeast of the site.
A January 1984 draft planning study published by the Delawar~ Valley
Regional Planning commission recommends that a four-lane arterial be built in
Upper Merion Township. This proposed Schuylkill Parkway is pro~soo to bt::
routed directly over the former lagoon areas.
SITE HISroRY
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The dump was owned and operated fran 1960 to 1968 by callpanies Qwnea by
Franklin P. Tyson and Fast Pollutant Treatment, Inc. Ciba-Geigy Corporation
had used the dump to dispose of various wastes during the same time peI"iOO.
General Devices, Inc.. the present owner of the site, purchased the pr01Jerty
fran Tyson in 1968 and claims they did not dump anything since they acquired
it. D..1ring active operations, several lagoons were constructt::d within the olu
quarry pits. Former lagoon locations, approximated fran 1965 anCi 1973 aer'iai
photos of the site area. are shown on Figure 2. Reportealy, liquid s~ptic tank
wastes and sludges were hauled to Tyson's DJrnp in bulk tank trucks and thtn
were disposed in the lagoons. Apparently, lagoons were till~ witb wast~s alia
covered, and new lagoons were created. These operations were carried out
throughout the site thus dispersing contaminants over much ot the tOur acre
area. Since lagool1s were not lined, wastes were not pr~vented fran migrating
off-site via seeps and shallow ground water. Although disposal at this site
supposedly was confined to septic tank wastes, the presence ot nazaraous
constituents in soils and ground water indicates that disposal o~rations
included chemical wastes.
~'
In 1973, the Pennsylvania Department of Environmental~ces ora~rea
the site owners to close the tacility. During closure, the lagoons wer~ t.o 00
drained, backfilled and vegetated and the lagoon contents transported ott-sitc.
Since closure, the 'site has been commercially inactive. '
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In January 1983, EPA investigated an anonymous citizen complaint about
conditions at Tyson's Dump and subsequently detennined tt~t tmmediate r~Qval
measures were required to limit exposure to public health by uncontrolled
chanical odors and liquid waste releases tran the unsecured slte. Nearby
residents were traversing the site daily and children were observed by Conrail
workers to be frequently riding motorbikes throughout th~ site. 1he SchuylKill
River received surface runoff fran the site and is used as a municipal water
supply. Norristown's main drinking water intake (10 MGD) is approximately ~O()U
feet downstream in the south channel between Barbados Islarx1 and the site. A
drinking water intake for the City of Philadelphia is locatecLappraximat~ly 13
miles downstream. The river is also used as an industrial';water supply tor tl1e
area, in addition to its recreational use by the general public.
A large quarry pit, located approximately 1 1/4 miles south ot the sit~,
is used by the Philadelphia Suburban water Company as a drinking water source.
This reservoir provides between 5 to 10 MGD. The floor elevation of the pit is
229 feet below HSL. Several private residences using wells tor potable wa~~r
are located within 1000 feet south and southwest of the site.
The initial environmental site survey and sampling results indicated that
a variety of hazardous chlorinated and non-chlorinated chemical Compounds were
present in the soils. air and water within and around the former lagoon areas
(on-site) and in the floodplain (off-site). EPA's On Scene Coorainatord~cided
to institute the following immediate removal measures in Harch, 19~3;
A security fence was erected to limit unauthorizea access to tile
site.
A leachate collection systen was constructed to minimize uncontrolled
contaminant discharges to the Schuylkill River and also to r~uc~
volatile organic air emissions.
An air-stripping leachate treatment system was installed to r~~ve
volatile organic campounds fram collected leachate.
An activated carbon air ,exhaust system was installed to trap liberd~ed
organics fram the air-stripper.
A partial site soil cap was placed over the suspected lagoon dr~dS
and hydroseeded.
The area was graded to divert uncontaminated runoff tram the old
lagoon areas.
An extent-of-contamination survey was conducted to det~rmine the ne~
for additional remedial measures.
Data generated fram the initial field activities COnd~ by EPA (January-
June 1983) indicated the widespread presence of organic ~~ within ana
surrounding the former lagoon areas. These materials were mt removed during
closure and still are present in substan~ial concentrations. The major
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contaminants found were volatile organic compounds (primarily xylenes, tolu~nes
and l,2,3:~trichloropropane). In addition, chlorinatea benz~ne canpounds cCIrlIrOnly
were detected.
'!he data collected was used in applying the Hazard Ranki~ Sys tern to the
Tyson's Dump site which resulted in an overall score ot 63.10. Remedial Action
Master Plan and Work Plan were prepared and approvf:Ci in September~ 1983. funding-
for the Remedial Investigation and Feasibility Study was also approved in trlat
~nth. -
CURRENT SITE STATUS
Intensive field studies were conducted during December 1983 through March
1984 by Michael Baker, Jr., Inc. under subcontract to. NUS Corpration. The.
findings and conclusions of the Remedial Investigation were sutrnitted in Auyust .
1984.
Air Quality, as determined fran volatile organic canpound measurem~nts ~ ha<.l
improved substantially subsequent to EPA's immediate removal actions. Results
of air monitoring conducted December 1, 1983, revealed none ot the 15 volatil4:
organic compounds evaluated were present. Since winter conaitions may have ~
reduced or prevented the release of volatile compounds present in trozen surface
or subsurface soils and other media, EPA requested that wann weather air mon'itur-
ing be conducted to measure the potential for local adverse air quality conditions.
Results of this monitoring did not reveal the presence ot any ot the volatile
contaminants found during the subsurtace soil sampling. Again, this may
be attributed to EPA's emergency response.
Surface soils located in the central section at the fenced-in area were
found to be highly contaminated with organic compounds. The level at
organic compounds tend to decrease with increasing distance fran the
center of the site.
Indicator parameters and their isomers which were used in assessing the
extent of surface soils contamination were chlorinated ~ropanes and dimechyl
benzenes (xylenes). The duplicate sample in the vicinity ot the ola lagoons
had the highest reported values: compounds (or their isomers) ~lich exce~ed
100nYJ/kg included dimethyl benzene, ethylbenzene, methylbenzene, trichloropro-
pane, hexadecanoic acid, and 2~hloro-10H-phenothiazine.
Lowalying areas downgradient from the site also show evidence at organic
contamination. With the exception of Benzoic Acid, no oth~r organic
canpound' exceeded 6 ppn.
Metal concentrations in the surface soils exhibited no clear tr~na that
would indicate that metal levels were higher or lower in a canparison ot tlood-
plain surface soils versus surface soils over the tormer lagoon locations.
When these areas are subsequently camparf:Ci to background levels (see tiQur~ 4),
there is no significant difference. The field levels are also representative
of typical soil concentrations as indicated by the reterence levels.
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Metal concentrations measured in surface water samples collected fram
the small tributaries, ponds, and the Schuylkill River did not exhibit any
trends or patterns with regard to site influences. However, sampling was conducted
during a period of lOw flow, and the streams and ponds were not receiving site
runoff. Sedtments provide a better indication of 10nq-term conditions since
typically the metals are sorbed onto solid matter and thus are more stationary,
especially during periods of low flow. SediInent samples collected at each
surface water sample location did not reveal an inorganic contamination problem
(Figure 5). These concentrations were similar to those found in surface soils
and thus may be due to native soil conditions.
SUrface water samples typically contained only trace amounts of the Hazard-
ous Substances List organic compounds analyzed. The two samples containing the,
most organic compounds were located in the tributary downstream of the leachate"
treatment plant discharge. Of the tentatively identified compounds determined
to be in surface water samples, 1,2,3, trichloropropane was the most prevalent
contaminant. This ccmpound can be related to the site because the stations
upstream of Tyson's Dump site either contained none of this substance, or for
the Schuv1kill River, only a trace amount. Figure 6 provides a summary of the
occurence of the hazardous substanance.
Sedbnent samples taken in ~he tributaries, Schuylkill River, and ponds
contained a wide variety of the tentatively identified compounds. The most
frequently encountered substances were trichloropropane and methylated benzenes.
Tracking the presence of trichloropropane in sediments, paralleled what was
noted for this canpound in surface water. Upstream of the site, there was
little evidence of this compound, while downstream it was always present. A
major area of concern on the floodplain is the qulley which receives the effluent
fram the present air stripping operations. These sediments were found to
contain fairly high concentrations of 4-methylphenol (25,000 ppb) and 1,2,4,
trichlorobenzene (44,000 ppb).
Metal concentrations above background were found in the ground water.
However, these concentrations may not have been indicative of in-situ conditions
since the samples were unfiltered (leaving sedllnents in the water), turbid,
and acid preservatives may have removed metals bound to the sedbnent particles.
A wide variety of organic canpounds were detected in monitoring wells south of
the railroad tracks. Contamination was also found to be widespread. Monitoring
wells located in old lagoon areas contain high concentrations (generally exceeding
10,000 ppb) of a wide variety of organic ccmpounds. Fewer organics were detected
in floodplain wells (constituents rarely exceeded 100 ppb).
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Figure 4
SURFACE SOIL COMPARISON FOR INORGANICS
Sample Means I Ref e re"ces
Parameter BackgroundJ. On-Site" Floodplain) Casarett'+ L1.nJsay)
& Doull's Low Hi. ~
Aluminum 7240 5220 5,580 81,300 10,000 30e
Chromium 7.0 7.4 9.9 200 1 1,G.Cc
Barium 106 50 90 400 100 3 ,CCc
Beryllium 0.77. 0.41 0.56 0.1 40
Cobalt 4.1 2.7 5.6 23 1 40
Copper 20 116 98 45 2 100
Iron 6280 4,015 11 , 100 50,000
Nickel 7.4 7.4 7.8 80 5 500
Manganese 222 63 230 1,000 20 3,000
Arsenic 7.4 5.1 9.2 2 1 50
Antimony <1 <1 <1 0.2 2 10
Selenium 1.1 1.1 1.1 0.09 0.: 2
Thallium <0.5 <0.5 <0.5
Zinc 24 47 51 65 10 ~ 300
Vanadium 12 <10 15 110 20 t 500
Silver <0.5 <0.5 <0.5 0.1 0.01 t 5
Mercury <0.1 0.48 <0.1 0.5 0~01 0.3
Tin .-- 18 13 72 3 2 200
Cadmium 0.41 0.43 0.91 0.2 0.01 0.7
Lead 28 26 59 15 2 200
Tox <100 118 <100
All values are in ppm
..
1. Samples used 840019, 840020, 840030, 840031, 840032, 840152, 840153, 840154
2. Samples used 840024, 840025, 840026, 840027, 840028,. 840155
3. Samples used 840034, 840035, 840036, 840037, 840038
4. Toxicology by Casarett and poul1's, 1980, p410
5. Chemical Equilibria in Soils by W. L. Lindsay, 1979
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Figure 5 .
UPSTREAM (BACKGROUND) VS. DOWNSTREAM (S I IE INFLUENCED)
SEDIMENT COMPARISON
FOR INORGANICS
Sample Means
Upstream I Downs t ream 2. Background
Parameter . Surf ace Soils
AlulDinum 2410 4030 7240 #.
ChrolD1um 2.5 10 7.0
Barium 38 83 106
Beryllium 0.28 0.64 0.77
Cobalt <2.5 7.3 4.1
Copper 16 25 20
Iron 2840 10,030 6280
Nickel 2.4 9.1 7.4
Manganese 104 577 222
Arsenic 3.8 6.4 7.4
Antimony <1 <1 <1
Selenium <1 <1 1.1
Thallium <0.5 <0.5 <0.5
Zinc 27 106 24
Vanadium <10 11 12
Silver <0.5 <.0.5. <0.5
Mercury <0.1 0 . 7,.4 <0.1
Tin 5.1 6.2 18
CadlDium 0.25 1.1 0.41
Lead 15 47 28
Tox <100 <100 <100
Oil & Grease 123 301.
All values in ppm
1. Samples used 840044, 941)058, 840072, 840074, 840151
2. Samples used 840046, 840048, 840050, 840052, 840054, 840056, 8/o1,)O~').
840062, 840064, 840066
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.
E'igure 6-
TYSON'S DUMP SITE
SUMMARY OF l,%,3-TRICHLOROPROPANE (OR ISO~~R)
RESULTS BY SM1PLE TYPES
ESTIMATED CONCENTRATION
Sample Type Frequency 1 Range ~z
.
1. Surface Water. 12/16 ND~-2,400 l1g/1. 450 \lg/l
2. Groundwater 6/21 ND-280,OOO l1g/l 13,500 \.Ig/1
3. Surface Soils 17/26 ND-320,OOO \lg/kg 22,200 \.Ig/kg
4. Subsurface Soils 21/24 ND-2S,OOO,OOO \lg/kg 3,200,000 \.Ig/kg
S. Sediments 12/17 ND-87,OOO \lg/kg 8,400 \.Ig/kg
lFrequency is shown as number of occurrences above the detection limit
per the total number of samples analyzed.
'Means calculated using a value of zero for all samples in which the
compound was not detected.
3ND - Not detected or reported for sample.
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- 6 -
SUbsurface test boring samples confirm the major finding of the ground
water monitoring. Extensive organic contamination on-site (concentrations
often exceeding 100 mg!kg extending down to at least 20 feet in several areas)
and minimal organic contamination on the Schuylkill River floodplain.
The environmental data collected at Tvson's Dump Site show that the most
severely contaminated media are subsurface soils located in old lagoon areas.
Thus the major pathway for the migration of contaminants off-site is via ground
water movement through these lagoon areas. Based on monitoring well static
water level measurements, the direction of shallow ground water flow is estimated
to be slightly east of north, toward the river. Permeability measurements
taken at various mnitoring wells indicate that ground water travelinq fran the
center of the site to the Schuylkill River would take approxLmately ten years
(60 feet per year).
Since the site was previously a sandstone quarry, the topsoil and overburden
were removed during mining operations. t'Ii th bedrock outcrops observed to be
highly fractured throughout the site and due to the nature of the previous
mining operations, a serious threat exists because leachate is probably migrating
vertically into the fractured bedrock zone as well as horizontally atop of the
bedrock surface.
Other pollutant pathways include volatilization of organic canpounds from
surface soils and on-site seeps. The emergency measures undertaken by EPA in
early 1983 appear to have dramatically reduced air quality problems, however,
these were only temporary actions until a permanent remedy could be Lmplemented.
Surface runoff of contaminated surface soils has been substantially
reduced due to the site regrading conducted during the emergency action. Since
the most severe contamination is confined to subsurface materials in the old
lagoons which is effectively isolated from direct surface runoff, surface
transport of organic compounds is limited.
The potential for health effects from direct contact with contaminated
materials is estimated to be low outside of the fenced area with the exception
of sedLments downstream from the leachate air-stripper effluent outfall.
Inside the fence line a threat does exist. should handling of contaminated
surface soils occur which can be absorbed through the skin. Disturbance and
handling of subsurface materials from the former lagoon area could pose a more
serious threat due to the high concentrations of numerous organic compounds
. be low ground.. .
As indicated earlier, surface water downstream from the leachate treatment
plant was the most contaminated. the plant is effective in removing many volatile
organic compounds, however, its efficiency for reducing other organic cOmpounds
particularly xylenes and 1,2,3 trichloropropane is undoubtedly lower.
No ground water users are located between the site and the Schuylkill River,
which is the direction of ground water flow. Several private water supply wells
are located within 1000 feet of the abandoned dump but are hydraulically
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upgradient in terms of ground water flow patterns in the area. Five residences
sampled duri~ the RI showed no evidence of contamination fran the site. Ten
organic compounds were detected in low concentrations in downgradient
floodplain roonitoring wells. This indicates that either dilution of contaminants
has occurred or higher levels of contamination have not yet reached these
~l~. .
The gross organic compound contents of on-site ground water and subsurface
materials, even after the site has been inactive for more than ten years, demon-
strates the persistance of contamination at Tyson's Dump. site. One of the major
site contaminants, tetrachloroethene, is a known anUnal and a suspected human
carcinogen if ingested. Several other contaminants found on-site such as
benzene and trichloroethene are also known animal and suspected to have human
carcinogenic ef.fects if ingested. Xylene, toluene, and ethylbenzene produce
narcotic effects in high concentrations. Due to inhalation, ethylbenzene and
trichloropropane are irritating to eyes, skin, and mucous membranes; dichlorobenzene
and trichloropropane can. cause damage to liver and kidneys and depression of
the central nervous system if inqested. Phenol is hiqhly poisonous either by
inhalation, inqestion, or skin absorption. 4-Methylphenol (p-Cresol) can be
absorbed through the skin and is known to cause kidney damage. It can also
lead to a sensitvity reaction. The compound, 1,2,4-trichlorobenzene, can be
absorbed through the skin and is an irritant.
AcrE RN!IT IVE S EVALUm- ION
The major objective of remedial actions to be taken at Tyson's Dump Site
is to mitigate and/or elbninate environmental contamination present; (1) in the
areas of the former lagoons which is roughly defined as within the fenceline,
( 2) the hills ide between the former lagoon areas and the I;"ailroad tracks, and
(3) the floodplain/wetlands. The overall strategy for former lagoon remedial
action will be to ~plement source control techniques to confine or remove
contaminated soils and subsurface materials as well as to ameliorate ground
water contamination.
Off-site (the hillside and the floodplain/wetlands) concerns stem mainly
from previous migration of hazardous constituents fran the abandoned dump.
Surface soil samples showed organic contamination in some areas. With the
exception of the intercepted leachate and contaminated ground water between the
hillside and the railroad tracks, subsurface soils and ground water contamination
were found to be low as indicated by the RI. On-site remedial measures should
focus mainly on assuring that the potential for additional contamination of
these areas is min~ized. A key aspect in determining whether off-site remedial
measures are necessary is the resolution of the effectiveness potential protection
factor associated with remediation of the scattered contamination found on the
hillside and. on the floodplain/wetlands versus the detremental effect of
disturbing the wetland.
Initial formulation and development of potential alternative actions were
based both on generic remedies and possible technologies applicable to these
remedies. A summary of initial sreeninq of technologies is presented in Figures
7, 8, and 9. Initial screening of technologies was based on 1) the reliability/
-------
Fiqure 7
Problftl Type
I. Air Pol1utlon
2. Solls/Sedl.~nts Cont..lnatlon
i
SIlMHARY or INITIAL TECHNOLOGI~ SCR£DnNG PROC£SS
PotentIal Technology
Scr~enlng ASS~8s8ent
CappIng with c16Y, asphalt, etc.
- Halard potential fro. aIrborne cont"lnatlon
does not warrant control 8easures based on RI
data.
Application of chftllcal sealants,
flxants, stabilizers
- Halard pot~ntlal
does not warrant
data.
fr08 alrborn~ contaalnatlon
control 8easures based on RI
--
Gas collection syste. with carbon
adsorption s,ste.
- Gas generation fr08 site not a prOblftl, pres~nt
air stripping leachate treat8ent s,ste. does
e.ploy carbon adsorption for exhaust vapors.
£Xcavatlon/offslte disposal
operation
- Viable option since 80st severe cant.-Inatlon Is
within a defined area (I.e., old lagoons).
Site capping
- Viable option to prevent direct contact with
contaalnated surface 50115 and to reduce
leachate generation.
Application of chemical sealants
- Unproven technology given trpe of chealcal con-
taalnatlon In surface 50115' .a, be Interference
with sealant properties. Require pIlot or bench
scale study using site soils.
Encapsu 1 a tI on
- Considered unpro.en technology for use at this
site.
",
Bulkhead construction
- Due to large volu8e of contaalnated soils and
phYSical characteristics of the site, this tech-
nology judged to be Infeasible without large
capital expenditures to lIIodlf, site lI.e.,
ext~nslve excavation, Much of which would be In
bedrock).
-------
FU
8
Problet! Type
2. Solls/Sedl.ents Canl88lnatlon
(Cantlnued)
, .
I
3. Cantulnated Groundvater
- ,
- Cantlnued -
Patentlal Technalogy
the.lcal flxant/salldlflcatlan
In-Situ treal8enl
Onslle landft II
Flushing,
Upgradlenl divers Ian via barriers
Upgradlent pU8plng
Upgradlenl trenches
Intercept Ian trench/subsurface
collectlan drains
Screening Assess.ent
- Jud~ed to. be unprayen technalogy far large
Yalu8e of che.lcal vastes.
- Posilian af vastes, difficulty In yerlfylng suc-
cess and lhe requlre.ent af a significant effart
to. test 8ethods prlar to. deter8lnlng feastbillt,
ell.lnales In-sllu lreat.ent as a technaloqy far
future canslderatlan.
- Viable aptian far Isalatlng vasles/cantulnaled
subsurface salls.
- Naste characlerlstlcs (low vater salublllly) and
palentlal far spreading cantulnatlan (parllCu-
larl, Into. deeper aquifers' rules o.ul flushing.
- Passlble technalagy althouqh past disposal af
vastes practical 1, against the aId quarry hlgh-
vall 11.lts area In vhlch to. canstruct an up~
gradient barrier.
- No suitable 1000tians to. place upgradAent veIls
to. dlYert grounavater fr08 site.
- Insufficient .rea to' excayate trench onslte.
- Viable alternatlye If coupled vlth groundwaler
t realilenl.
-------
Fiqure 9
. Continued .
hobl- Type
Potential Technology
3. Contolnated Groundvater
(Continued)
Nell pU8plng systell
Per.eable treat.ent beds
OUsite disposal
Onslte treat.ent
In-situ treat8ent
Dilution
Screening AssesS8ent
. Possible technology, but vould provide the 8811e
effect as trench. Trench preferred because It
is a passive .ethod not requiring collection
pu.ps and should be IIOre effective In collecting
shallow groundwater .Igratlng off site.
Insufficient area to Install beds, potential for
shortclrcultlng; doubtful that treat.ent would
be successful In re.ovlng che8lcal constituents.
- As long as burled vastes re.aln In place, re-
.oval and offslte disposal of groundwater would
be necessary. DIsposal costs high.
- Possible 8easure since leachate treat.ent plant
already at the site (although upgrading system
necessar,) .
. Insufficient. proof that ~thod vould be success-
ful. Would require bench scale, then pilot
plant studies before feasibility detetlllr.ed.
"
- Potential for forcing cont..lnaled groundwater
Into deeper aquifer, no known equlclude under-
lying site to pr...nt this froe occurring. Also
potential for Incre.stng offslte cont..lnatlon,
Increasing conta.lnant .Igratton rate and levels
toward Schuylkill River.
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- 8 -
effectiveness of the technology in protecting the population and environment
potentially at-risk fram site contamination, 2) the engineering feasibility of
the technologr'.for implementation at Tyson's DlUnp and 3) costs involved of
installing or ~lementing the technology.
The initial screening process resulted in a reduced list of possible remedial
actions for further evaluation. These alternatives selected for consideration,
.addressing both on-site and off-site contamination, are listed in Figure 10.
ON-SITE AND HILLSIIE ~ffiDIAL AIIERNM'IVES
AIIERNM'IVE 1. EXCAVATION/OFF-SITE ~~VAL
This alternative consists of excavating the contaminated soils, fill .
material, and wastes (est. total volume approx. 30,000 cu. yds.) and transporting
these to a secure permitted landfill with a double liner, double leachate collec-
tion system for disposal. Excavation limits will be b3sed on organic contamina-
tion found on the surface and on bedrock depth at the locations of the former
lagoons and well-defined quarry pits. Removal of contaminated materials is a
highly effective, permanent (useful life) solution to prevention of 1) hazardous
subtances migration off-site and into ground water, and 2) direct contact -
,
exposure with contaminated soils. It is highly reliable as successfully .
demonstrated at previous sites and requires little or no operation and maintenanc~.
. Criteria for excavation will be b3sed on removal of unconsolidated materials
down to bedrock in the lagoon areas. The lateral extent of excavation will be -
based on detectable b3ckground levels in the on-site area. Contaminated ground
water/bedrock will. be dealt with through the waste management treatment process
to assure that hazardous substances do not continue to migrate into-the ground
water. Under RCRA, a facility needs to remove waste to b3ckground levels or cover
area with a cap. A cap in this situation would not be desirable since any
residual contamination could be flushed out and treated in the waste management
treatment system.
Shallow contaminated qround water encountered within the excavated areas
will be routed to an upgraded treatment facility, and then discharged in similar
fashion as the present air-stripping system. Air-stripping will reduce the
amount of hazardous substances discharged to levels which will assure
protection of water quality. The treatment system is located in the flood
plain and will be designed to protect against washout. With excavation only
planned to 0CCQr in the former lagoon locations, an off-site remedial measure
is necessary' to handle residual leachate and shallow contaminated ground water
within the steep hillside between the fo~r lagoons and the railroad tracks.
Residual flow collected in the existing interceptor trench installed during
the removal will be processed in the upgraded treatment facility. Effluent
from this facility will then be discharged to the same tributary which is
currently receiving the air stripper's effluent. This is estimated to continue
for about five years as clean shallow ground water purqes this area. Acceptable
levels of contaminants in the ground water will be established in the off-site
roO. These levels will assist in the determination of when additional treatment
of ground water is no' longer needed.
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- 9 -
A sufficient nlmbet of monitoring wells (at least four) designed for pOtentia'
ground water recovery will be installed during the design phase to determine if
the lower aquifer is contaminated. Additional monitoring wells may be necessary
due to the invariability of the Stockton Formation, the ccmplexity of ground
water flow in this aquifer, and the heavy inrniscible ccrnpounds such as the
1,2,3 trichloropropane: it is conceivable that the contaminant plume may bypass
this rnonitoringsystem. If these wells do not indicate contamination in the
deep aquifer, it will support a no-action solution. Should contamination be
present, a subsequent RI/FS will be necessary to determine lateral extent and
levels of contamination, and to identify proposed remedial measures to address
such contamination.
This alternative would require improving the site access road to haul
hazardous materials out by truck and rehabilitating the local township roads
due to the movement of heavy equipment and truck traffic.
Air emission controls and surface water run off controls will be ~le-
mented during the design Qhase to minimize releases. However, a temporary
evacuation plan for local residents and other safety measures can adequately
address these concerns. .
AITERNl
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- 10 -
there are several disadvantages. Difficulties are expected in anchorinq the
surface cap iIIto the quarry highwall. In addition, wastes may be incanPatible
and could cause the grout curtain to fail. D.1e to fractured nature of the bedrock'
a continuous grout curtain is complicated to install and it is difficuit to
ascertain whether a complete barrier to ground water flow is established.
Should the grout curtain fail to provide a complete barrier, the contaminants
would continue to migrate through ground water transport off-site. In addition,
upwelling of the ground water into the contaminated area is anticipated and
therefore would allow the contaminants to continue to migrate. Finally, conta-
mination could move into deeper aquifer throuqh fractures, and if so probably
would not be intercepted by leachate collection trench.
AI.:I'ERNXI'I\E 3. - GOOUNI:Wa'ER/rEACHAI'E CDLrEcrION AND TffiATr-ENI'; SURFACE $ALING
OF CONI'AMINl
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- 11 -
soils. A double-lined system with leak detection and leachate collection should
have a useful. life of greater than 30 years. The level of clean-up would be
sUnilar to ~~cavation alternative. Operation and maintenance requirements
entail perpetual ground water monitoring and inspection of the leak detection and
leachate collection systems. The landfill portion of the site will be permanently
restricted. The present air-stripping facility would also need to be retrofitted
based on results of a treatability study of the leachate. The Rillside subsuc~ace
soil contamination will be handled silnilarly as described in Alternate 1.
RCRA permitting personnel from Region III reviewed the site characteristics and
location and ccrnpared that to their locational guidances. The determination was
made that it was highly unlikely that a RCRA Landfill would be permitted at
the Tyson's site location, for the reasons indicated below as "critical factors".
In addition, the cost estbnate in the feasibility study could be increased by
approximately $800,000 or more to address other factors. The problems associated
with establishing a landfill in this loca~ion (eg. foundation, liner and slope ,"
stability, need for additional qround water monitoring wells) could effect the
quality of installation and also result in a further increase in cost. (See
Appendix A for more specific detail). Following are the critical factors viewed
as disadvantaqes for the on-site, secure landfill.
CRITICAL FAcrORS
Protected Lands
Siting of a landfill near protected lands such as
wetlands is not recommended based on the potential
detrimental effect the landfill could have on these
lands if releases occurred and were not remediated
in sufficient ttme.
Ground Water Monitoring
- Monitoring must be established at a landfill to
Unmediately detect co~tamination release. Due
to fracturing in the bedrock, releases could
occur without being detected in monitoring wells.
Also, fractured bedrock would significantly
increase the difficulty of cleaning up any conta-
mination.
Ground Water Vulnerability
- Time of travel to target areas (wetlands and surf.ace
water drinking intakes) is much less than the
recarmended time of 100 ft in 100 years. At
Tysons, time of travel is 100 ft in 10 years.
Time to Achieve Remediation - The on-site RCRA landfill would require the longest
amount of time to achieve remediation (the exca-
vation and Off-Site Removal Alternative is ex-
pected to require only 6 months). Dalays in
remediation would allow further migration of
ieachate fran the former lagoons which may
increase both lateral and deeper contaminant
levels, and place an additional burden on
the temporary measures installed during the
immediate removal.
-------
- 12 -
AU'ERW«' M 5 - ro Acr ION
This alternative represents a situation where there would be no further
remedial actions Unplemented on-site. Althouqh the leachate collection and air-
stripping equipnent does reduce air emissions, it does not reduce all organic
concentrations in the leachate prior to discharqinq to a tributary of the Schuylkill
River. Ground. water vulnerability of the Class II aquifer and Umpacts to flood-
plain/wetlands and the downstream river intake necessitates isolating/removal
on-site wastes. Without ellininating or isolating the contaminated subsurface
soils and preventing miqration of contaminated qround water, the site probably
will revert to a situation slinilar to that which existed prior to EPA's emergency
response actions which would be a reoccurance of localized air emissions, additional
ground water contamination seeps from the hillside, and contaminated surface
water run-off. In addition, surface soils, through erosion and dissolution
processes,. could contribute to contamination of surface waters on and off-site.~.
Contaminated subsurface materials in direct contact with the shallow ground water
or through downward migration of surface precipitation will adversely affect ground
water quality. Additional intermingling of contaminanted soils with the rising.
ground water table would also increase contamination to the. ground water.
Thus direct contact threats and additional environmental contamination fram
the migration of the contaminants into the ground water and wetland area
would continue.
OFF-SITE rer-EDIAL AIXERNM'I\ES
The evaluation and selection of off-site remedial action is being deferred
with the exception of the tributary that recieves air-stripper effluent. Due
to high orqanic levels in the sediment, which are presently a direct contact
threat, approxllnately 50 cubic yards will be excavated from the tributary and
disposed of off-site at a RCRA landfill. This is considered to be an interim
measure. A determination if futher remedial action is needed will be made in .
the off-site ROD. The factors for deferal are:
(l)
the four existing monitoring wells in the floodplain/wetland area will
be further sampled using field filtered methods to obtain accurate
results for the metal concentrations in the ground water
-------
SUMMARY 01" ALTW{NATIVI:;S
.. . - - - - . - o. - - - . . . . - . . . - - .
," .......
- -- A-1tprnatlve-a-nd1cos'ts- '($K'fj' - -PubYic'. ~.e"c11t'h' - -. - -. ~- - - Env-ir~mmen-ta'l .. - I. - . 'lbchnical I I
~~r~:men.!:~- -- - ~?P.. -. 9~~.. - - ~~!I~_i9~.r?~_i~!I~--.- --- _S~!I~_i~~.r~_t_i9!1~u - --. - .I. - .S9~1?_id~F~_ti~~I~. - o. 1_-- -- - -- ~~Ilt::.r- 0 - . .- - -.- - i
1".U Excavat10n and 5.718 351 TEmporary evacuation Eliminates future air IContaminalits will IA (Jouult.; llllt;;u U' I
I Removal * I 10f local residents am GW deterioration. be nsnOVed to back- I in can~liance wIth I
may be warranted. Removes threat ot dir- yroun
-------
- 13 -
( 2)
A wet~and assessment will be done in order to better determine the
ber~fits and/or detriments that any remedial action would have on the
wetland area
(3 )
A biological study will be done in order to better determine any effects
that off-site contamination would have on the wildlife in the wetland area
For purposes of an interim cleanup measure, based on a toxicological assessment
(attached) * The levels to be removed are as follows: above 500 ug!kg for 4
-methylpheno1 and 2 mg!kg for 1, 2, 4, trichlorobenzene.
CONSISl'ENCY WITH ornER ENVIro~M:NI'AL rAWS
Alternatives were examined in 1iqht of relevant Federal, State, and local
environmental program requirements for actions such as disturbance of floodplainS",
temporary and permanent discharges to the 'Schuy1kill River for treated wastewater,
air emissions from the treatment plant and disturbances of contaminated soils,
and RCRA requirements for new landfill facilities or existing landfills to
receive excavated wastes.
The design and construction of the upgraded treatment facilities will be
coordinated with the State to assure that receiving water and air quality
will be aduquately protected.
.
,
/
I
-------
- 14 -
m COMl-ENIE D N::r ION
Section 300.68(j) of the National Contingency Plan (NCP) states that the
appropriate extent of renedy shall be determined by the lead agency's selection
of the remedial alternative which the agency determines is cost-effective
(i.e., the lowest cost alternative that is technologically feasible and reliable)
and which effectively mitigates and minimizes damage to and provides adequate
protection of public health, welfare, or the environment. Based on our evaluation
of the cost-effectiveness of each of the propJSed alternatives, the ccmnents
received fran the public, and information received fran the Pennsylvania
Department of Environmental Resources, we recanmend:
HILLSIIE AreA -
FORl>ER LAQX)N AreA - Source Control Measures. Excavation and off-site
disposal of contaminated materials at a permitted .
RCRA landfill in compliance with the current off-site ,"
disposal policy.
Off.:site Remedial Measures. Continued use of existing "
leachate and shallow GW collection trench. Upgrading.
air stripper to treat flows. Discharge to tributary
which is currently receiving air stripper effluent.
Further studies will be conducted to determine if
removal of surface soils will be necessary.
FDOODPLAIN!WETLANDS -Interim remedy of selective excavation in the tribu-
tary which receives air stripper effluent to decrease-
direct contact threat and enviornmental damage. Final
decision on Floodplain/wetlands remedial action will
be made in off-site ~D.
The alternative of excavation and off-site disposal of contaminated soils;
fill materials, and wastes to a permitted RCRA landfill was selected based on
its reliability in eliminating the continued generation and off-site migration
of leachate fran the former lagoon locations and the continued contamination of
both shallow and probably deep ground-water zones. Based on the results of soil
borings, there are no appreciable clay layers between the fill in the former
lagoons and the fractured bedrock. This condition leaves little doubt that the
contaminants have a pathway into the fractured bedrock aquifer.
In definiDJ, excavation limits must be carefully defined. Analytical
data fran test borings taken in former lagoon locations indicate that organic
concentrations tend to increase with depth down to bedrock (approxbnately
t~nty-five feet at the deepest point). Based on aerial photographs of the
former lagoon areas coupied with analytical results and cross-sections from the
test borinq program, it is believed that most of the unconsolidated soils and
materials in these areas are contaminated by various organic canpounds. There-
fore, the maximum limit of excavation is estbnated to be approxbnately 30,000
cubic yards and is represented on figures 11 and 12. This limit is also reflected
-------
- 15 -
in the cost ~-..te for this alternative'. An onqoing contamination detection
program will l5i*.oonducted during excavation to separate clean materials that
could be usect-fn site reclamation frcm co.ntaminated materials. Any unconsoli-
dated materials in where no contamination' is detected above background soil
levels will be.used as clean fill on-site.
Excavation of unconsolidated materials and wastes is expected to progress
without difficulty until encountering bedrock. The bases of the former lagoons
are probably contaminated along with vertical fractures and deep ground water
below the bases. Retrieval and/or containment of deep aquifer migration fran
the former lagoons will be further investigated. .
In an effort to avoid creating a depression which would accelerate the
natural flushing of the bedrock and the deep aquifer, and also to prevent the
potential for direct contact should an upgradient flow of contaminated ground
water occur, the excavated pits will be backfilled, and graded to prevent
surface run-on and direct run-off. Site reclamation after removal will include
grading, and revegetation to elUninate physical hazards fran the excavation
pits. .
Prior to commencing excavation, the following measures will be linplemented: .
Improving an access road to the site to handle the movement of heavy
equipment and truck traffic.
Upgrading and retrofitting the present air stripper to treat leachate,
contaminated ground water, and surface run-on encountered during ex-
cavation~ ~sign parameters for the upgrade will be based on a
treatability study of the collected leachate and shallow ground
water. This facility will also continue to operate after excavation
until monitoring data indicates the quality of any residual flow is no
longer contaminated.
Formulating an air monitoring plan and temporary evacuation plan for
protection of local residents.
Transport and off-site disposal of all solid wastes will be conducted in
accordance with RCRA. Off-site incineration of excavated fl\aterials was invest-
gated but due to the limited availability of commercial facilities, the tLme
required to process the materials (minLmum of three (3) years - no staging of
wastes at incinerator) and the lowest estLmated cost obtained {$2lM, just for
incinerationJ,. it was decided that the to landfill alternative was more appropriate.
As a less expensive approach to transporting the excavated materials, "piggyba~king"
(rail and truck) was also considered but did not project significant cost'
savings.
The one area of concern off-site is the tributary which recieves the air
stripper effluent. Concentrations of organics are much hiqher compared to
other areas of the floodplain. It is estimated that fifty cubic yards of
contaminated soil and.sedbnent will be removed from the tributary where the
air stripper discharge outfall is located. This involves excavating approximately
-------
- 16 -
the top six.(61~ inches of soi1/sedlinent within the tributary from the outfall
point to the SChuylkill River. Clean fill will be' used to restore this area so
as not to affect the original drainage pattern. Upgradinq the air stripper
facility will further prevent surface water and sediment contamination.
Removal and disposal of spent carbon cannisters fram the existing air
stripper will also be required regardless of which alternative was chosen.
There are presently seventy-two exhausted cannisters which increase at a
rate of four per month. Regeneration of the spent carbon will be investigated
during design.
ore RAT ION AND MAINI'E NANCE
Post excavation activities include continued collection and treatment
of residual leachate and contaminated shallow ground water. Monitoring,
until data indicates that treatment is no longer required, will be performed
periodically. It is anticipated that by removing the source of contamination,
the quality of leachate and contaminated ground water will qradually improve
so that the operation of the treatment system will no longer be warranted.
This time period is estilnated to be five years.
sam OOIE
Approve Remedial Action (Sign ROD)
Amend Cooperative Agreement for Design
Complete Enforcement Negotiations
Start Design
Canplete Design
Amend Cooperative Agreement for Construction
Start Construction
Complete Construction
12/29/84
12/31/84
2/28/85
March 1985
July 1985
July 1985
Sept. 1985
March 1986
EVALUATION OF AcrERNATI'£S oor !:EIECl'ED
The GW Diversion and Site Capping alternative was not selected due to the
inability of this alternative to deal with the existence of shallow ground
water and the threat to deep aquifer contamination. Some of the cross sections
representative of different stations through the former lagoon areas show the
shallow water table to be wi~~in the contaminated sub-surface materials (see
fiqure 10). Higher water table levels would be expected than those measured
during the remedial Investigation since in-situ qround water elevations taken
durinq,.the winter would normally be' lower when c"mpared to elevatlons taken in
the Spring. . Even with an effective grout curtain the water table may well-up
behind the curtain and again came in contact with contaminated materials.
The difficulty of constructing an effective grout curtain at this site (due
to fractured nature of bedrock) lowers this alternative's reliability. Even if
the barrier is originally structurally reliable, the existance of larqe hydro-
static pressures on one side and corrosive organic compounds on the other side
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- 17 -
of the grout curtain raises the likelihood of diversion failure. Should this
barrier not ~fully effective, or later fail, there is no secondary or back-
up protecti()$"~~ich would prevent ground water flow through the contaminated
soils, and therefore would result in futher miqration.
The Collection and Treatment alternative was not chosen since the threat
to deep aquifer contamination will not be mitigated. As noted earlier, this
alternative will not assure that hazardous substances will not migrate into
the ground water, moreover, since there is no means of estimatinq the quantities
of hazardous substanceswhich may migrate into the ground water, this alternative is
most inappropriate. .With shallow ground water flowing toward the Schuylkill
River, the intercepting trench should collect most of this flow. However,
even with the trench constructed 5 to 10 feet deeper into bedrock (of which
itself could cause additional fracturing), leachate which exits through the
base of the unlined former laqoons into a fracture will very likely not be
intercepted. As mentioned in the site description, the Stockton Formation
aquifer is controlled by deqree of fracture and fracture orientation. Heavier,
llTImiscible organic compounds would pass below the intercepting trench even
assuminq that the general direction of flow in the deep aQUifer is similar to
that of the shallow aquifer. This collection and treatment alternative entails
This collection and treatment alternative entails longer and more complex
operation and maintenance requirements than the. other alternatives. Based on
the potential for recontamination, due to the unlined former laqoons, this.
factor would lower the alternative's reliability. The service life of the
surface cap if allowed to remain undisturbed can be considered permanent.
Another drawback with this system is the problems which might be encountered
during the operation and maintenance period, (eg. clogging of the interception
trench, malfunction of collected flow pumps, a decrease in removal efficiency)
then any extended break in operation wouid result in recontaminating the flood-
plain/wetlands since there is no back-up system.
-
,
I
-/
The On-Site Landfill was not selected based on various factors.
The major drawbacks to this alternative are: 1) ground water vulnerability,
2) ground water monitorability, 3) potential Umpacts of protected lands,
4) double-handling of contaminated materials and hazardous wastes, 5) long time
frame needed to acheive remediation. In light of these factors, the on-site
landfill is not adequately protective of human health and the environment.
EVALUM'ION OP.lUI'ENl'IAL resroNsIBIE PARrY'S proros=:o AU'ERNATI\B
Ciba-Geigy,one of the potential responsible parties at this site, had
submitted comments and also discussed in a meeting their recommended remedial
actions i:o bE! implemented at the site. Their proposal is similar to Alternative
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- 18 -
3 (Interceptioo Trench; Treatr.1ent of Leachate/GW; Su-rface Cap) with several
modifications~ -
Ciba-GeLgr's proposed major modification to Alternative 3 involves the use
of deep (20-30 feet) interception wells instead of the proposed (5-10 feet deep)
interception trench. Their reasoning based on the belief that "by virtue of
pumping the wells and creating cones of depression and areas of influence around
the wells, water within fractures not directly penetrated but interconnected
throughout the rock mass would result in interception of that water through the
pumping wells."
A major defficiency in this alternative would be the potential for continued
migration of contaminants into the lower aquifer. This particular remedial
technology had been eliminated during the initial screening in the Feasibility
Study report. It was judged to be ineffective because the wells would have to
be spaced such that they are within the fractures in order to prevent ground
water fran bypassing this collection system, which is impractical. This was
the basis for selecting a trench over downqradient wells. The trench would
intercept more fractures.
Of additional concern is whether the migration of heavier orqanic contami-
nants will be toward the line of interception wells. Heavier contaminants tend
to be affected by gravity rather than the ground water flow field. Even with
additional interception wells installed on three sides of the site (Ciba-Geigy
proposed only one line), the heavier Ummiscible contaminants will probably flow
through the secondary structure of vertical joints and not necessarily along
isotropic flow paths to the interception wells.
An Dnportant feature of the interception well strategy is developing
cones of depression in an attempt to maximize collection of contaminated
ground water. Although the Ciba-Geigy proposal does mention the collection
of large quantities of ground water, there is no estimate as to these
quantities during the design life of this alternative. It is expected that
pumping will be continuous due to high yields characterized by the Stockton
Formation and high water table levels in the vicinity of the site due to
the area being an aquifer discharge zone. Very steep depression gradients
will need to be maintained in order to direct contamination toward the
wells. The extensive pumping and subsequent treatment requirement:9 were
not factored into the operational cost of the Ciba-Geigy proposal.
Ciba-Geigy's a second proposed modification to Alternative 3 is the instal-
lation of a fteshwater recharge system (similar to an on-lot sewage disposal
system) to accelerate the flushing and removal of contaminants fran the former
lagoon areas. The present (non-recharge) Alternative 3 estimates that migration
of contaminant!:. will last greater than thirty years based on the persistent -
nature of the contaminants, while Ciba-Geigy's modification would be intended
to purge the former lagoon contents in a five to ten year period. Even if
this could in fact be accomplished, the recharge operation would probably also
drive the contaminants deeper into bedrock fractures, exasperating the threat
to the deeper aquifer.
Ciba-Geigy CorPOration also provided comments indicating that the Exca-
tion and Off-Site Removal Alternative is not desirable because of potential
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. - 19 -
adverse impacts to hunan health, engineering and technical constraints, and
the ICM cost effectiveness. The Agency believes that the need to prevent
further migration of hazardous wastes fran the former lagoons into the
underlying bedrock aquifer (a Class II aquifer), outweighs the risk of evacu-
ation and the temporary inconveniences caused during the excavation of wastes.
Thus, at this site excavation/off-site disposal is. the only alternative
which is feasible, reliable, and provides adequate protection of public health,
welfare and the environment.
ENroRCEr-ENl' HIsrORY
After discovery of a release of hazardous substances in January 1983
and prior to initiation of the bnmediate removal action, EPA gave notice
and opportunity to perform the ~diate removal action to General Devices
Inc. and Frank Tyson. Both p~rties declined to take ilnnediate action.
In April 1984 a CERCLA 107 cost recovery action was filed against
General Devices Inc., Frank Tyson and Ceiba-Geigy Corporation (identified
as a generator based on information received in response to a 104(e)
response}. The case was filed to recover the immediate removal costs and
remedial response costs to date (amendments to the case will be made as
remedial costs are incurred). The case is now in discovery.
On ALgust 1, 1984, as the RI/FS was nearing canpletion, EPA sent notice
letters to all three parties asking them to consider linplementing EPA's
chosen remedial action (although the action was not known at the tUne).
Frank Tyson repsonded by stating he could not afford to take any action.
Ceiba-Geigy and General Devices did not commit to taking any action, but
did indicate an interest in engaqing in discussions that could lead to a
clean-up. On October 26, 1984, Ceiba-Geigy wrote to EPA and again stated
they have not ruled out the possibility of voluntary remedial action and
asked EPA not to make comnitments to federally-funded remedial response
until discussions are held.
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TYSON'S DUMP SITE
I
r-DN'I'GGlERY COUNTY. PENNSYLVANIA
f
"
RESPONSIVENESS SUMMARY
-------.----------.--. --
Tyson's Superfund Site is located in Upper Merion Township, Pennsylvania.
It is a highly eduacated, alii knowledgable canmunity. where people are
predominately upper middle class. Citizens and local ofticials are willing to
cooperate with EPA officials in supplying information about the sit..;. A stroOd
working rapport has developed between the canmunity and local otticial~ and £FA
officials.
..'
Tyson's Dump Site was of major concern to residents ana local otficials
during the remedial planning stage of the project. Ccmnunity int~rest bt:..'ga!l ill
March of 1983, when a press conference and a public meeting were held to aiscus~
emergency actions to be taken at the site. Approximately sixty residEnts WE::re
in attendance. The citizen's main concern was the high level of cancer aeaths
within a one-half mile radius of the site. Residents attributea ti1e deaths to
the fact that the young men lived close to the site. They were tour youths in
their late teens who used to play. hunt. and ride motorbikes t.hrough the area
over the years before the site was knavn to be a hazardous area. In reply to
these concerns, the Environmental Protection Agency: Region III contact:.t::<.1 ttLe
Center for Disease Control. CDC compared cancer statistics ana touna that'
there was not a higher incidence of cancer in the vicinity of the ~ite: as
compared to the rest of Upper Merion Township. The EPA responaed to initial
cQncerns by monitoring ground, air and water within the nearby Valley Brook
Development and by informing residents that there was no contamination to their
immediate envirornnent. Residents and local developers were also concernt::U wltll
property values in the developments close to Tyson's.
Immediate removal actions were underway in April of 1983. At that time:
an extent of contamination survey was conducted, former lagoon areas were
regraded wi th clean fill, and temporary caps were placea on the lagoons. A
security fence was constructed around the entire site, a leachate collection
and treatment system was installed, along with a storm water management :::;ystem
for the site. Vegetation was planted for erosion control purposes. . I)Jring t.he
Immediate Removal activities, the citizen's concerns continued to center on th~
frequency of cancer deaths. They were also concerned with the time tramE: 1:or
total cleanup of the site, and removing all of the contaminated soil ana
disposing of it off site. At the public meeting to discuss the anergency
actions, EPA officials told the residents that permanent cleanup ~lternatives
will be addressed in the Remedial Investigation and the Feasibility Stuoy~
During and after the emergency work, federally elected ofticials tour~
the site, and State, local and federal officials fram the area urged that EPA
and the State propose Tyson's for the Superfund National Priorities List. 1ne
site was put on the proposed list in Septanber ot 1983. In OCtober 01: 19~3, a
public meeting was held to discuss the workplan. Approximately titty I:Jeople
attended the meeting. The citizens continued to voice their concerns, the high
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- 2 -
cancer death'rate in the area being their primary concern. '!he people unaE::rstC<.Xl
EPA's pUlpQa-:.for doiB;;} the study, however, they pushed heavily tor a quick'
cleanup. 'ItieY. continued to urge total excavation and oft site disposal ot
contaminated.- soil. The Upper Merion Township Board of Supervisors also urgea
EPA to llnplement off site disposal ot contaminated soils trom th~ siee. BFA
officials moved quickly in the remedial planning activi ties. Thert~ was quick
turn around tllne between the site making the National Priorities List. dI~ t[~
completion of the draft workplan one month later.
A publ ic meeting to discuss the Draft Remedial Investigation (RI) Report
and Draft Feasibility Study (FS) was held on October 10, 1984, at the Upper
Merion Township Building. About sixty-five concernw residents attena~ ttle
meeting. Prior to the meeting, the Draft Remedial Investigation RetJQrt ana the
Draft FEasibility Study were placed in a repository at the township building
and the local library, for three weeks, for public review. At that tim~: the'
citizens had the opportunity to. review the documents and comment at the ~ublic'
meeting. A pre meeting was held earlier on October 10, 1984, to di~cuss the
EPA's finding with the upper Merion Township Manager, and his Environm~f1tal
Advisory Council. The council is made up of a group ot five resiaents ot Upper
MerionTownship, who have background in engineering or environmental scienc~s.
They strongly backed the township's position for excavation ot soil and oft -
site disposal. In readiOJ the RI Report, the Township environmental council '
disagreed with the low to moderate water 'risk assessment ot contaminated surtac~
water migrating from the site. They feel that the water risk is too low and /
unrealistic because the flow from the site is toward the Schuylkill Rver, which
runs along the site. The concern w~th that is, the local high school crew team
uses the river adjacent to the floodplain, downgrade from the tormer lagoons.
Because of this, they believe that off-site removal is ap~ropriate.
The four cancer deaths were mentioned during the pre-meeting. The tuwnship
Environmental Council was emphatic about eliminating any potential cause ot
cancer in the area. Despite cns statistics, the council. was hignly concerned
about the four youths who died of cancer.
Another major concern of the Upper Merion Township Manager, is a proposed
four lane highway, which is still in the planning phase. TI1is highway is
intended to alleviate heavy traffic through the ccrnmunity. This proposed roaa
would run tight through the area of the site. as a bypass to the heavily
travelled main taoa through town. Local officials believe there is a strong
need for the. highway. According to township officials, not constructing the
highway ~d be detrimental to camnunity growth. would maintain a hign level
of air pol.1tition and would have a negative impact on local business. Construction
of ,the ~.will be ~ssible, however. if the contaminated soils remain ot
the site. This issue was previously discussed earlier. in September ot 1~84.
bet'Neen the Township Manager and. EPA officials. That meeting took 1>lace one
rronth before our Otober RI/FS meeting, spec i ically to discuss the plans tor the
new highway. DJring the OCtober pre-meeting.. the to\tmship Manager repeatealy
stated that he feels the proposed highway is an essential means ot dealing with
the. increased traffic throughout the township.
On the evening ot October 10, 1984, the public meeting was held, with
approximately sixty-five citizens in attendance. About half of those residents
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- 3 -
asked EPA officials questions about the work at' the site over the past year.
The canceJr concern was raised at the meeting. Residents said that the cases
were too s~ilar to not count the site as a possible cause or aggravation of
the condition. All the residents who spoke were strongly opposed to any on-
site facility being built for cleanup of the site. They also were in tavor ot
Alternative #1, Total Excavation and off-site disposal. The coincidence that
the cancer victims frequented the area in the past was a major issue with the
residents. .
The citizens also were concerned'with how quickly EPA would decide on
alternative. They want the project to be cleaned up as effectively and rapidly
as poss ible . .
The residents were asked to send their written comments to EPA, Region
III. The comment period lasted fran October 11, through Nov~r 7th. wring
that tUne. we received seven individual letters fram. residents who live in the
developnents borderng the site. Included in the correspondence was a letter
fram the parents of two of the young men who died of cancer. Allot the comm~nts
favored total excavation and off site disposal. They receiVed written comments
fram two of the potentially responsible parties. One ot those parties sent a
letter indicating that they are in favor of Alternative #2, Site Capping and
Groundwater Division. The other party indicated, in a written report, that:
they find a modificationof Alternative #3, Groundwater/Leachate Collection ano
Treatment and Surface Cover, acceptable. These suggestions were addressed in'
the Record of Decision.
we also received a written comment for total excavation/ott site r~val
fram a State Senator. We received a letter indicating that the Upper r.1erion
Township Republican Committee strongly supports the township's position tor
total excavation and off site disposal. A letter was receivt:!Cl tram the township
manager- repeating the issues and concerns discussed at the pre~eeting on
October 10, 1984. We also received a petition containing 1,000 citizen
signatures, requesting total-excavation and off site disposal ot contaminatE:d
soil.
Throughout the comment period., the ci tizens were told that they could
contact Region III at any tUne to discuss any concerns regarding Tyson's site.
However, most of the residents chose to correspond througp mail, or through the
petition that we received.
Once the alternative is approved, before we begin the design/construction
stage, a public meeting will be held to discuss the wor~. EPA Region III will
continue ~ provide community contracts for the residents, should anyone have
qUestions or concerns during the design/construction phase.
-------
ATIA~l' A
PRELIMINARY RE.VIEW OF
TYSON'S OOMP SITE
FEASIBILITY STUDY
ON-SITE IANDFILL ALTERNATIVJ::;
-------------------.------.---.
EXECUTIVE SUMMARY
- -.- - - - - - - - .. - - - - - - .
The RCRA Per.mits Section (3HW33) was requested to revi~w the reasibillty
of the on-site landfill alternative as presented in the Dratt Feasibility
Study -(FS) for the- Tyson's Dump Site located near Norristown. PA. Specitically
to be addressed was whether the proposed alternative- would meet current l~CAA'
technical requirements and guidance. .'
The review concentrated upon three (3) areas lbniting site locational crl-
teria. design/construction feasibility and linpact ot recently enact~a ~C~ ~r~-
ments. The findings ot the reV1ew con(;l.UUe that no clear-cut constrcunt.~ wen:
found which would prohibit the siting or construction ot the on-site lanafill. -
However. several deficiencies and sign1t1cant constra1nts were touna WhICh, 1n'
the final analysis. makes this alternative an untavorabl~ one. A summary ot tilt
significant constraInts ana aet1clenC1es ar~ presented below. /
1. !9~n9?_t}'_0!l--s~~p_i}._i~y' This is conSiderE:C1 not to be a I:JrolJl~1 exc;ept
for the waste pile location proposed over the abandoned lagoons where ~x~c;t~
significant differential settlements would crack or rupture a liner. Also,
shallow groundwater levels will require constructlOn or seJ.ect t~.1.1 to raise th~
liner system of the landfill.
2. ?~?~_5i!~ili~y.' Long-term stability ot the quarry high wall against
which the landfill will be constructed may be a problem. "Slab" or "block"
slippage may occur due to the frequent vertlcal jointIng ana weaKly cem~ritea
structure of the rock along with anticipated seepage pressures on the quarry
face.
3. Protected lands' ReM requires canpliance wi th Presidential E.xecutive
Order 1199
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- 2 -
The ntIIIber and location of canpliance point wells proposea is !lot sutticiEi
either. 'Ib& canplexity of the groundwater flow and potEmtial co ntami cia lit Pl.Uffit..:
direction in the jointed. sandstone bedrock, which is located within 15 teet ot
the surface-, was raised.
5. Groundwater vulnerability - The site is located over a Class II
aquifer. °L'€pencHng-upon- l"n:'srtu-b€drock permeabilities- the site may be classi1:lt'::O
as a vulnerable setting based upon unofticial Phase II dratc locaClon gUlaance
criteria.6 -
However, of more concern is- the hlgn ~DneaDllltles'ot the cOlluvial/
alluvial soils located downgradient of the proposed lanotill and within tile
floc:xjplain, which is a groundwater discharge zon~- ShoUlO COntaIIllnancs leal<.
fran the landfill.. they may impact the wetlands ecosystem and th~ SChi..lylKill ,
River before appropriate corrective action could take place. Under 4UCrR 264-1GO(c)
of RCRA, corrective acti -- must begin within a reasonable time penod att~r th~
migration of hazardous co~tituents has been detect~ by the cam~llance rnoniturir~
system.
6. Liner system design/construction feasibility - the construction 01:
the liner. system- against- the-steep-quai-iy high walT is not possibl~,
as proposed. Site developnent to flatten slopes is required resulting
in less disposal capacity. A chimney drain against the quarry wall
appears to be needed to relieve any groundwater seepage b)ressur~ on
the quarry face and maintain the integrity of the liner system.
7. Run-off Management' Collection ot run-ott tran the lanc1till <.luring ltS
active liI"e-(6- rnonths-)-ancCits management as a hazardous wast\:: will bt:: l"~quir~.
Sedimentation control to collect suspended hazardous waste (soil-, colloias, etc.)
will be needed. The run-off which will mix with leachate during the active lanotill
life will also need to be managed as a hazardous wast~.
8. ?_(~e_- ac-,~_e;;~j.p_il-_i_t:L~-~E~.!1~t 5iF~_a' Signiticant slte constraint.::. ror-
delivery of materials. personnel and equipnent am construction actlvities exist.
Only one entrance to the site exists and is the only one teasible. The railroaa
right-of-way to the north and the quarry high wall to the south ot ttle site
presents limited working space to efficiently expedite the work.
9. Waste_man~ement s~~.' The alternative requires handliCXJ wastes
twice in level 8 personnel procectlon- excavatlng then transr.
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- 3 -
Sane of thelia- wastes are metals and organic HSL canpounCls dlat have been idtmtitiE:U
during the:~ either in soil or water. Should the t:irne trame tor thf:: aesign ar1Cl
constructi~:of the landfill be such that disposal of these wastes woulo take
place after-the above effective date. then the restrictions would apply. Ott-site
disposal would not be llnpacted by these restrictions due to the shorter t1me
frame in which this could be accanplished.
Although the guidance for groundwater vulnerability site locatiunal Crlt:encl
(see item 5. above) has no present regulatory basis, ~202 requirt:s publ.lcat.iun
of this criteria by May 8. 1986. This is well within the time fr~ that it
will take to implement and complete the. activities for construction ot the land!i~~.
Secondly, the amendments require pranulgation ot regulatior~ which will s~city
acceptable 'site location criteria thus reinforcing U1e present Pt1aSE:: I gUlOdllCf::.5
-
,
t
I
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--
TYSON'S DUMP SITE
----.. --.-- ...- ----.--.--
DRAFI' FEASIBILITY STUDY
-.-------.----------------
RCRA EVALUATION OF THE ON-SITE
. -----tANDFYii--ALTERNATIVE- - - -
--..---------------.--
A. INTRODUCTION
-- - _.- --- -_._-
Due to the inherent complexities involVed with any lana disposal design.
. the preliminary evaluation of the on-site landfill alternative as prCSt:C1cea
in the Draft Feasibility Study (FS) had to be approacIied on tnree (3) l.evel.s.
First. the alternative was studied on the basis of whether ics reasibllity would
be precluded on the basis of clear evidence that the site was unsuitable due tq
limiting site locational criteria (high hazard/unstable: terrain, grol.J.nc1water .-
monitorability/vulnerability, protected lands. etc.). The second level ot
evaluation looked at the site fram the viewpoint ot whether the alternative
proposed could be feasibly built from an engineering design/construction stand--
point. Lastly, the impact of "The Hazardous and Solid ~-~ste Amendments vt 19d4"
enacted November 8, 1984 was evaluated. .
Al though the firs t two of these appr.oaches could be usee as a oas is leadu19
to denial of a land disposal RCRA permit, the second one is more subtle in its
determinatlon in that the alternative is presented, at best, on a conceptual
basis and the detailed study associated with tinal design may resolve or clarity
any shortcanings.
-
,
The above evaluative approach was not only used to determine tI~ reasiOility
of the proposed landfill itself but also that of the cernporary waste pile ~toraYb
areas which are an integral part of the lanc1f ill alternative. And as will .De
pointed out later, there are regulatory requirements tor waste piles. which, at
first, will seem superfluous because of the time frame (6 montill,) tor the stJecitic
activities involved or scope, but will have a signiticant lInI,Xict or! ~t::lecting
the best alternative.
B.
LOCATIONAL CRITERIA
-------
Although the Phase IS locational guidance criteria are in tinal craft torm.
existing regulations do allow their implementation. Phase 116 whicl! aadrcsses
groundwater vulnerability is in draft form and has not been ofticially r~leasee
to date. '!his- criteria is tied into the Groundwater Protection Strategy (G\.PS)
and at the present time has no regulatory baSlS (See Section D). Only those
locational criteria which are believed to be applicable to the proposed landtill
alternative are addressed herein. -. .
1.
!iigh- hazaE?lunsta.!>le- _t~.FraiE
a.
E'oundati9E_~.!abj.J.i ty
The FS proposes that the landfill will be construct~ in the western
lagoon area requiring removal of the lagoon contents and contaminated soils
where it is to be sited. Conclusions reached in the Ranedial Investigation
(RI), indicate~ that up to 20 feet of wastes have been buriea and placed airectly
-------
TYSON I S DUMP SITE
DRAE~ ~'-EM;"IB-ILI1Y STUDY
RCRA- iVAibATIO~f o~,- THE- O"N:'SITE
- --- -lMIDFIU.-AtTERNATI\iE- --.- .
-_. - - - - - --- - - -.-.- - - - - - -
A- INTRODUCTION
----------
Due to the inherent canplexities involved Witll any land disposal design.
the prelilninary evaluation of the on-site landtill alternative as ~r~s~ntea
. in the Draft Feasibility Study (FS) had to be approached on three (3) levels.
First, the alternative was studied on the basis ot whether its teasitJility \'Joula
be precluded on the basis of clear evidence that the site was unsuitable aue.to
lilniting site locational criteria (high hazard/unstable terrain. yrouncwatcr.-
monitorability/vulnerability, protected lands, etc.). TI'~ secund level ot .
evaluation looked at the site fram the viewpoint ot wtlether the alternative
proposed could be feasibly built fram an engineering design/construction stand-
point. Lastly, the ilnpact of "The Hazardous and Solid Waste l>Inendments ot J.9~4"
enacted November 8, 1984 was evaluated.
-
,
Although the first two of these approaches could be used as a basis l~adi~
to denial of a land disposal RCRA permi t, the seconc one is more subtle in i t.S
determination in that the alternative is pr~sented. at best, on a conceptual
basis and the detailed study associated with final design may r&solvb or CL~£lti
any shortcanings.
The above evaluative approach was not only us~ to ceteDnin~ tile teasibilic~
of the proposed landfill itself but also that ot the te~rari wast~ ~l~e sturQ~~
areas which are an integral part of the landfill alternative. Acd as Wlll ~
pointed out later, there are regulatory requirements ror waste pll~s: which, at
first, will seem superfluous because ot the tilne frame (6 months) tOl' the Sb£CltlC
activities involved or scope, but will have a signiticant Lmpact on ~elcctir~
the best alternative.
LOCATIONAL CRITERIA
- -
B.
Although the Phase IS locational guidance criteria are in tinal craft !ODm,
existing regulations do allow their ilnplementation. Phase II6 which ad
-------
upon the UDderlying bedrock. and, that groundwater - apparently basec1 on levels
measured iilfJarruary C!!l~ !~b~_a'!y- 9}- JJ.!3_4, occurs wi thin the buriec1 was te- zon~s.-
(The FS ~states that these high levels may be due to mounding within the
lagoons) .
Since excavation of the wastes to bedrock will be necessa~ to
remove all wastes, landfill liner instability due to foundation tailtlre or s~ttl~-
ment would be highly unlikely. However, since the liner and associat&d leachate
collection/leak detection systems would have to be construct~ above s~a50nal
high groundwater levels (which would be above those rep::>rte<1 auriC¥J. the winter
months) backfill of up to 10 to 15 teet ot costly select material tor ~tructural
till can be expected. PA DER further requires the liner to be 4 teet above
seasonal high groundwater and 8 feet above "nonnal" or averagt: yrounawater levels.
The use of select material will be required in order to provide the relatively
incompressible, stable foundation for the landfill and associatea lin~rs ana "
leachate ~ollection/leak detection systems. The use of select materials is al~o
necessitated by the "wet" conditions (created by the shallow grounawatt;;r) irlto
which the fill will be placed in the excavation.
On the other hand,. the stabili ty of the foundation ot the temporary
waste pile storage area is questionable and could limit the fe.asibility vf tEmtJOr-
arily storing these materials on-site. The FS proposes two (2) alternative'
waste pile locations~ one with and the other without a liner. The regulations:
for waste piles require use of a liner and leachate collection system unless the
design will prevent migration of any hazardous constituents into the groundwater
or surface water at any future time.
It can be assumed that a liner would be required~theretore. it
appears that placement of the temporary waste pile at the tirst location ov~r
the eastern lagoon area is not suitable. Differential settlement due to the
varied location and depth of the lagoon wastes beneat11 the pile would no coubt
be too excessive for any liner material or leachate collection systt:m. This
could be minimized by removing the weak, canpressible tilled wastes anu contam-
inated soils. But this would obviate the need to site the pile at this location
when the second alternative location exists.
The second or far eastern location proposed tor the temporary
waste pile where lagopns or wastes were not placed is believea .to i:;e su~table.
Campressibilities of the alluvial/colluvial 30ils tflat exist would be limitea
and can be minbnized through appropriate site preparation (excavation and backtlll
of weak soils, deep canpaction via heavy rollers, or site preparation techniques
similar to that required for the landfill).
b.
Slope Stability
The long-term stability ot the steep slopes (averagiqJ betwet::n
20 and 100 percent and vertical in sane areas) along the southern permeter ot
the site need to be closely examined. The site history indicating tbat it was
used as a quarry would suggest that groundwater seeps oischarging on the quarry
high wall would occur. Published geologic literaturel,2 places the slte in .
the lower member of the Stockton Formation. The ridges typical ot t1"lis member
are mainly comprised of coarse to very coarse grained arkosic sandstones and
-------
conglomerate "poorly sorted and weakly cemented" with occassional interfingering
of shale and siltstone. These ridges approximately parallel the strike (roughly
SW-~) qf the beds. ~athering processes of these weakly cemented sandstones
and sha1es are the forces which deposit the colluvial materials which can typi-
cally be found at the bottcro of steep slopes.
The lower member is further characterized by appreciable secondary
structure consisting of vertical jointing which roughly parallel the strike and
consequently the ridge and quarry high wall. Freezing water and frost heave
within these joints and along the interfingered shale bed contacts would occur.
Canbined with gravitational forces possible "slab" or "blockll movanent or slippage
towards the face of the quarry high wall could be initiated.
These above-noted clLmatic and geologic conditions will, to varying.
degrees, affect the stability of the quarry hiqh wall and to a degree the liner "
and leachate collection/leak detection systems constructed against it. In the
final analysis, it is recogni~ed that the landfill will be constructed over a
short period of tLme (six (6) months) and a significant portion of the landfill
will be constructed against the high wall minLmizing slope failure. The issue
is raised, however, since exposure of the quarry high wall will still exist and
this site feature will also Umpact the design/construction feasibility of the
landfill as discussed later under IlSection C.II
The site also exhibits a similar steep slope between the proposed
landfill and railroad right~f-way. The FS shows, however, that the slope is
developed prLmarily upon the natural colluvial/alluvial soils. Although these
soils will, in small part, form the foundation for the landfill and stability of
the slope and these soils will need'to be examined, their existence would not
preclude the landfill construction on the basis of limitinq site locational
criteria. Conventional foundation preparation and slope stabilization techniques,
such as benching, compaction, etc., are available. .
2.
Protected lands
The landfill is not proposed within the floodplain zone defined by
the 100-year flood elevation of +80 and is, therefore" not situated within the
wetlands adjacent to the Schuylkill River. The operational definition and iden-
tification of wetlands has been recognized not to be an exact science. The U.S.
Fish and Wildlife Service can provide a wetlands summary of the site and coordi-
nation with the Corps of Engineers is also advised~
Discharge of sediments which will have an adverse impact on municipal
water supplies, fishery areas, recreational areas and shellfish beds are
prohibited. The alternative which requires excavation anc handling of contam-
inated soils' and wastes .to temporarily store and subsequently dispose of them in
.the new. landfill provides the likelihood that such impacts could occur.
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'!his waste management scheme coupled with the occurrence ot stormwatf-
run-off ani groundwater seeps south of .the dumpsite which could rrouilize tile
contaminated sediments and wastes create a negative side to this alternative.
It is true that these affects can be mitigated by run-on diversion structur~s,
erosion control structures, etc., as the FS states. How~ver, the available
working area is extremely lbnited by ~xisting site conditions (quarry high wail,
steep slope on nothern perimeter, existing drainage-ways, springs and leachate
collection ditches, railroad right-of-way, etc.) which add signiticantly to the
complexities of ilnplementing these safe-guards (also reter to Section C.2.).
Lastly, the location of the existing leachate collection and trea~nt
system within the lOO-year floodplain (and in some areas within the 50-year
floodplain) met with concern. Inundation of these tacilities would be severely
detrw~ntal to their operation, require more maintenance and significantly short~n
their life span. During the required 30-year post-closure care perioa, the
chances are as much as 60% (30-year care period/50-year flood trequency) that.
floods would ilTIpact these facilities. Therefore, any alternative Mlich intena~
to upgrade this treabment facility should consider relocation outside th~ lOU-year
floodplain. .
3.
Groundwat~r monitor~_ility.
-
.
The 40 CFR 264 Subpart F, "Groundwater Protection", r~ulations requ{re
that a groundwater monitoring system be installed, maintained and samplea during
a landfill's active Ilte and closure and postclosure perlOOs. A review ot th~
proposed and existing monitoring systems identitied in the FS reveals llnmeaidc~l
that no background groundwater quality system has been installea or even pr~Sed..
Based upon inferred groundwater flow directions it WOuld appear that a
system of upgradient wells would be required to monitor background groundwater
quality: be installed along the ridge south of the dump site; and, be screened
throughout the saturated zone to a depth sutficiently below the bottom ot the
landfill. Total well depths would exceed 100 teet. The lilTIitation that is
recognized, however, is site accessibility for the background monitoring system.
The system would need to be sufficiently tar enough tram the landtill as to not
be impacted by any liner leaks which may develop along the quarry high wall.
Heavy inmiscible contaminants. such as the 1,2,3-trichloropropane ana other
Appendix VIII constituents required to be analYZed under RCRA could attect samples
from "upgradientll W"ells located near the landfill. These heavy contaminants
tend to be affected more by gravitational effects than by the groundwater tlow
field. As such, they will flow through the secondary structure ot vertical
joints and not necessarily along the flow paths of an isotropic fODmation.
The solution which involves locating the background quality wells sutficiently
far fram the facility is hampered should permission ot adjacent land-own~rs
south of the si te be required to install these W"ells. Use of those residential
wells located south of the site and sampled during the RI could not meet the
regulatory requirements for a background groundwater quality system du~ to tbeir
locations, probable limited depths, questionable ability to obtain representative
samples, construction, if known, and limited zones that are screenea, it they
exist. .
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n.'other regulatory requirement associated with the groundwater moni-
toring s~ involves installing a sufficient number of wells which will yielo
samples ~ are representative of the groundwater flowirg unaer the lan<1tlll
and passing, the CCltIpliance point (refer to 40 Cf'R ~264. ~5) . The canpliance
p:>int wells must be located at the downgradient limit ot the waste management
area, i.e.. just beyond the landfill limits. Here again the existing or ~rq..Gsi::d.
wells would not satisfy the canpliance point monitoring systan. These wells
would have to be located just south of the railroad right-of-way.
Only two (2) existing wells, ERI'-l and 2, penetrate the lower mem.oer ot
the Stockton formation, the aquifer of concern. However, neither one ot thes~
are located along the compliance point based on interred groundwater flow Olrec-
tions. Secondly the RI/FS noted that wellERr'-l, which consists ot a bedrock ana
an unconsolidated screened well cluster revealed "a slight artesion conaitlOn~"
This conclusion is questioned and it is believed that the "artesion conaiti(;n~.
may have been mistaken for one typical of discharge zones. The bedrock Wt:ll is
only ten (10) feet deeper than the unconsolidated zoned well ana l'rIdy 0c r.1~c:;suriny
"elevated" piezanetric heads due to a shallow upward flow path (Le. shallow
discharge zone in the floodplain of the Schuylkill River).
The four (4) prop:>sed wells sited as two (2) clusters and located north
of the railroad right-of-way would not ~ adequate or meet the intent of the '
canpliance point groundwater monitoring system. First, they are located too tat
apart (about 600 feet) with only one (1) cluster north ot the proposed landfill
location. Second, the canpliance point, as defined by their locations, is 250
to 400 feet beyond the limit of the waste management area or lanctill. Ana'
lastly, they are located within the 100-year floodplain and, in tact, near the
50-year flood elevation of +77.
The purpose of locating the canpliance point groundwater monitoring
system at the limits of the waste management area is to proviae early aet.€::ction
of contaminant release so that tbnely corrective action can be taken betore
receptors are impacted. Bail tests pertormed in two (2) wells (I.\jUS-4 and NLJS-5)
revealed perrneabili ties in the 10-5 tt/sec. range. However, greater per:meabili tles
in the floodplain were evidenced by the RI study which noted rapiu r~charge in
well NUS-7. Based on this, perrneabilities in the rarge.ot lU-4 ft/sec. may be
conservatively presumed. Using this permeability value ana the values ot graaient
and assumed effective porosity reported in the FS the contaminant plume (ignoring
attenuative effects and dispersivity) would llnpact the Schuylkill River witr!in
one (1) year after reaching the proposed compliance point wells. This is tar
too short oe a time to develop and ilnplement appropriate corrective action as
required uncfer 40 CPR ~270.100(c). Furthermore, impact to wetland soils ~uld
have alreadY. occurred once the contaminants were detectea ana shortly thereafter
possibly to Norristown's surface water supply intake dowr~tream~
To surmnarize the above points, based on 1) the potential limitations ot access i-
bilityfor background groundwater monitoring wells; and 2) possible difticulty
in locating a canpliance point groundwater roonitoring system that woula allow
timely corrective action: the site may not meet the RCM groundwater monitoriI'XJ
requirements and would be unsuitable tor a landfill.
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4. Q.~~ter vulnerabil_i~-
Al~h presently not haviOJ any present regulatory basis, site loca-
tional criteria is presently und~r developnent limiting siting ot lane babE::<.1 H~-iM
facilities in vulnerable settings. Essentially, a vulnerable setting is' one
where the natural terrain or subsurface stratigraphy ~uld not provide containm~m:.
of contaminants should the engineered containment structures (liner and covl:r)
fail: and the facility is above Class I or II groundwater as detined in the
Groundwater Protection Strategy (GWPS) (based on present draft guiaance).
The site is located over a Class II aquifer which under the GJPS is one
that is currently used or potentially available for use. The vulnerability of
the setting above the Class II aquifer does not consider whet.her it is presently
used or the proximity of present users (i.e. wells) to the site. BaSed on un-'
official draft guidance, a vulnerable setting is based on time ot travel {TOT"-
of groundwater flow ignoring attenuation, ilmniscibility ot cuntaminants and
non-saturated flow zones. Furthermore. the affect ot engineered containment
structures are not considered. At the present time, draft guidance defines a
vulnerable setting for a landfill to be one where the TOT per 100 teet is less
than 100 years.
The reason that engineered containment structures (i.e., caps and liners)
whether constructed of clay or a flexible membrane liner (FML) are ignorea is /
that it is recognized that eventually ~lese structures will leak.3 Therefore,
EPA is developing this vulnerability criteria to protect Dmportant aquit~rs ana
groundwater resources should the engineered containment tail.
Groundwater. flow parameters for tIle unconsoliaated materi~ls noted in
the FS indicate flow rates of about 2 inches per day. Although the path ot
least resistance may be through the overlying unconsolidated materials as statE::O
in the FS, interconnection and appreciable downward flow into the lower member
Stockton Fonnation aquifer is considered highly likely. As discussoo earller,
secondary vertical joints occur in the fonnation and the landtill will be situatt.-d
directly on the bedroCk in those areas where the liner is locatea the minimum
distance above nonnal and seasonal groundwater levels (see Section B, ~ara. la).
An indication of the site's potential vulnerability can be evaluated un
a preliminary basis. Using those parameters established tor the unconsolidated
zones, a TOT per 100 feet of 1.4 to 1.9 years results. PenneabilitiE::s in the
bedrock can.~.expected to be lower than those determined in the unconsolidated
soils. ~Shed laboratory analyses of rock core sample~ fram the lower m~r
of the St~. Formation found horizontal peDmeabilities ot 0.003 to 0.03 gpa/tt~
(4.7xlO-9 bO.~~7x!O~8 ft/sec.) and vertical permeabilities of 0.OU03 to 0.U4 .
gpd/ft2 (4~7x!0-!0 to 6.2xlO-8 ft/sec).! However, laboratory peDmeabilities
are not indicative of in-situ conditions especially where secondary structure is
prevalent and has a significant llnpact on grou~Gwater flow rates and direction
as discussed earlier. Groundwater flow conditions in such bedrock is very di~ti-
cult to detennine even in the field. Rima. et. al.l, address this in attempting
to characterize the Stockton Formation via pumping tests. The conclusion's tram
these tests were:
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" the Stockton formation does not respond to pumping as an
ideal aquifer would. !'No (2) reasons for this are that the
fOIInation is not isotropic, and it is. not infinite in area.1
extent. It contains an alternating sequence ot matt=rials ot
grossly different hydraulic properties that are lntermi~loo...
Even those individual beds that appear to have a unitorm
permeability throughout their extent do not contorm to the
ideal-aquifer concept, owing to their lenticular ~ha[.€ and
differences in thickness fran place to plac~." 1
C.
ENGINEERING DESIGN/CONSTRUCTION FEASIBILITY
1.
LanE!ill liner system
The proposed landfill design incorporates a double liner syst~ ot
synthetic over clay with a leak detection system between the liners and a lea<.:bate
collection system on top of the synthetic liner. This rne:ets the intent ot th~ .
40 CFR ~264.301 design requirements for new landfills and present design guicmic~.
However, the feasibility of constructing this system along the steep tace ot the
quarry high wall is questionabl~. Certainly the liner system cannot ~ installed
prior to placement of the wastes unless slopes are signiticantly flattened on
the order of 3h:lv or preferably flatter. Synthetic liner materials can be 1
"draped" or installed vertically as long as the thickness is increased to accoUflt
for the additional stress (30 mil is reccmnended minimum thickness tor "conventional"
sloPed surfaces) and proper anchoring is provided. The slo~ recamnena~, however,
is more fran the standpoint of constructability of the various canpactdCl soil
layers~ Le., drainage layers and clay liner.4 The trade-off to bJroviai~
flatter slopes is, of course, less disposal capacity. The alternative to tlatten-
ing the slope along the quarry face is installing the system as wast~ dis~al .
. progresses. However, here the signif icant construction and Wr::t::. canplt:xities
involved would negate the landfill as a viable alternative.
The other consideration which needs to be addressed. is in the aesign ot
the system. As discussed earlier in the report, slope stability and groundwater
seeps on the face will place forces on the liner system which' it may no~ be able
to handle. If it can be assumed that the weight ot. the landtill zone will resist
the slab or block slippage on the quarry face then this concern is minilniZed.
However, seepage pressures against the quarry face will need to' be relieved via
a "chimney drain" type structure so as to preclude intiltration of groundwater
through the clay liner and into the leak detection system which would give a
false indication that a leak in the synthetic liner had occurred.
. 2.
Management of Run-off
Under 40 CPR ~264.3(c}(2), precipitation run-ott is excluaed as a
hazardous waste. However, during the active life of the landfill {6 m:mths
duration} this run-off will pick up suspeooed hazardous waste aOO mix with the
leachate. RCRA guidance7, therefore, states that run-ott tran active portions
will generally be a hazardous waste. As such, the run-of f needs to be collect-ed
and treated on-site or disposed off-site as a hazardous waste. Sea imentation
control procedures will also be necessary so that they do not Unpact the wetlanas
and discharge into the Schuylkill River. '!he collt:ctea seaiment will have to 01;
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','
.
removed f~the sedimentation control structure and managed as a hazardous wast
11'Ie regulaCtCl'J& under 40 CFR S264.301(d) requirl: that th~ run-ott system ~
designed m.'.~2S-year, 24-hour storm. '
The alternative to the above management procedures is to pertorm wastE::
analysis of the run-off on a periodic basis to aemonstrate that it is not a
hazardous waste. However, the practicality of such a burden may not outw~igtlt
the management procedures discussed above. '
3.
Lbnited site access and working area
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Located at the west end, only one entry onto the site is available to
deliver needed construction materials, equiI,YClent, arxi personnel ana ffilergency
vehicles and equipnent, if necessary. Canbined with the Ibnited space be twet:: n,
the quarry wall and steep slope along the southern perimeter ot the railroad .'
right-of-way, significant constraints are placed upon construction etticit::ncy
and plannirYJ. Movement of construction equipment and personnel access to trans-
port the lagooned wastes tWlce, construct the leachate collection and l~ak uetec-
tion systems, surtace run-off diversion and erosion control structures ana !:Jrovid-
ing an area for decontamination are all hampered. '!his can only add to the time
frame for construction, increase costs and aftect the overall quality ot the
project.
/
I
4.
Wa:;te management sCE~~
In terms of the overall management of wastes on-site durin;J constructi
of the landfill (the handling of wastes twice, temporarily storing thern in a
waste pile and achieving the level of environmental control and personnel site
safety required) the landfill alternative is viewed skeptically. '
Based upon the waste characterized, preliminarily there apl~ars to be
no canpatibility problem. However, during excavation an appro~riatE:: waste samplirtd
plan is required to: confirm waste canpatibility, determine level ot personnel
protection and appropriate management in the temporary waste storage pilt::(s).
Aside fran the site constraints, significant tbne delay is to be expectE::d to
handle the wastes twice in Level B site personnel protection. Volatih:s wLLl Lot::
expected and proposing a winter construction period'for the landtill in order to
minbnize their release is offset in part by typical winter construction uittlcultit::s.
'!he, FS discusses the possibility of degradation of local air quality
and the evacuation of local residents in this event. Although a wino rose was
not provide4to show prevailing winds, evacuation of residents and workers in
the City of Rorristown less than 3000 feet away to the north across the SChuylkill
River is not viewed as a viable approach.
IMPACI' OF RCRA AMENrMEN'IS
D.
The proposed landfill includes a leachate detection system bet~en the
liners. However, S202 ot the amendments requires that a leachate collection
system be placed between the liners.
The amendments under S201 include restrictions, includin;J bans, on tht::
disposal of certain hazardous wastes and liquid hazardous wastes contained in a
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solid or ~~~~ These restrictions are applicable to soil or aebris contaminat~
by these ~~ and disposed after November 8, 1988 tor 104 or 106 C~CLA actior~.
Sane of ~ wastes are the metals and organic HSL cat1{X)unds that have been.
identified during the RI either in soil or water. Should the time trarre tor tlie
design and construction of t.!1e landfill be such that disposa1-",ot these wastes
would take place after the above effectivt: date, then the resitriccions would
apply. Off-site dispOsal would not be impacted by these restrictions due to till:::
shortE?r time frame in which this could be accanplished. "
Although the guidance for ground water vulnerability site locatlonal criteria
(see item S. above) has no present regulatory basis, ~202 requires public~tion
of this criteria by May 8, 1986. This is well within the time trazre that it
will take to implement and complete the activities tor construction ot the land-
fill. Secondly, the amendments require pranulgation of regulations which will',
specify acceptable site location criteria thus reinforcing the present Phase !.
guidance.S
E.
CONCLUSIONS
The on-site landfill alternative for the Tyson's Dump Site was rev"iew~ and,
as a final analysis is a questionable one. Although there were no clear-cut'
site locational constraints that would prohibit the siting ot the landfill as :
proposed under RCRA (at least on a conceptual basis as prese:ntoo in the E'S),
there are significant ones that are noted. Costs were not addressed herein
since they have no impact on RCRA technical requirements, howevt:r, costs will be
higher than estimated due to these constraints and the deficiencies (site cnarac-
terization, groundwater monitoring, and liner design, for example) discusseo.
""
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