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Site Number: |
B52B |
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Contract Number: |
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D.O. Number: |
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Action Memo Date: |
10/9/2012 |
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Response Authority: |
CERCLA |
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Response Type: |
PRP Oversight |
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Response Lead: |
EPA |
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Incident Category: |
Removal Action |
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NPL Status: |
Non NPL |
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Operable Unit: |
OU3 and OU4 |
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Mobilization Date: |
6/20/2013 |
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Start Date: |
6/20/2013 |
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Demob Date: |
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Completion Date: |
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CERCLIS ID: |
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RCRIS ID: |
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ERNS No.: |
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State Notification: |
Ohio EPA notified |
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FPN#: |
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Reimbursable Account #: |
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1.1.1 Incident Category
PRP Oversight
1.1.2 Site Description
The SDDL Site is a former industrial
landfill located at 1975 Dryden Road in Moraine, Ohio. It encompasses a total of 80 acres, 65 of
which contain landfilled waste.
Approximately 40 acres of the landfill has been built over and/or is being
used for other commercial/industrial purposes.
The Site operated from the early 1940s to 1996
and is a filled sand and gravel pit and contains household waste, drums, metal turnings, fly ash, foundry sand,
demolition material, wooden pallets, asphalt, paint, paint thinner, oils, brake
fluids, asbestos, solvents, transformers and other industrial waste. As the excavated areas of the Site were filled,
some of the property was sold and/or leased to businesses including Valley Asphalt
and other businesses along Dryden Road and East River Road. The Miami Conservancy District owns the southern
part of the site including part of the large quarry pond.
Site Background –
1946 thru 1996 Landfill Operations
Disposal of waste
materials began at the Site in the early 1940s.
Materials dumped at the Site included drummed wastes. Known hazardous substances were disposed at
the Site, including drums containing hazardous waste from nearby facilities. Some of the drums contained cleaning solvents
(1,1,1-trichloroethane ["TCA"]; methyl ethyl ketone
["MEK"]; and xylene); cutting oils; paint; stoddard solvents; and
machine-tool, water-based coolants. The
Site had previously accepted materials including oils, paint residue, brake
fluids, chemicals for cleaning metals, solvents, etc. Large quantities of foundry sand and fly ash
were dumped at the Site.
A
timeline of the Site history is presented below.
·
During the 1930s,
excavation activities began according to the aerial photographs.
·
In 1940, landfill operations initiated at the Site.
·
In the mid 1950s,
buildings were constructed on the portions of the Site adjoining Dryden Road
and businesses reportedly began operation.
·
In approximately 1956,
Valley Asphalt began operations on the northern part of the site.
·
In 1969, the Montgomery
County Health Department (MCHD) first licensed the Site as a solid waste
disposal facility permitted to accept commercial and industrial wastes.
·
In 1974, the Ohio EPA
took over the authority for annual licensing; however, the licenses continued
to be issued by and overseen by MCHD on behalf of Ohio EPA. The last license granted by Ohio EPA was
issued in 1986.
·
As of 1987, the Site's
Permit limited materials for disposal to construction and demolition debris.
·
In 1990, the Site stopped
accepting and disposing of fly ash at the Site.
·
In early 1996, the Site
closed.
Site Background –
Remedial Investigation/Feasibility Study
EPA conducted a screening site inspection of the Site in 1991
and a focused site inspection prioritization site evaluation in 1995. Ohio EPA conducted a site team evaluation prioritization
of the landfill in 1996.
In 2000, Valley Asphalt removed several drums and 2,217 tons of contaminated
soils from their property (northern area of the Site) that was uncovered when a
sewer line was being excavated. EPA
proposed the site to the National Priorities List in 2004.
In 2006, several potentially responsible parties (PRPs) for the
Site agreed to conduct further studies and evaluate cleanup options at the Site
under a Remedial Investigation/Feasability Study (RI/FS). The RI/FS is being conducted under an Administrative
Settlement Agreement and Order on Consent with EPA. In 2008, the PRPs agreed to conduct a streamlined
RI/FS at the site. EPA approved these
work plans, and the PRPs conducted several investigations at the site from 2008
through 2010.
The 2008-2010
investigations included geophysical surveys, test pit and test trench sampling,
vertical aquifer sampling, landfill gas sampling and groundwater monitoring well
installation and sampling. The groundwater
contamination (above MCLs) along the eastern boundary of the Site (Dryden Road)
included TCE, vinyl chloride, cis-1,2-dichloroethene (cis-1,2-DCE), benzene,
arsenic and lead.
Preliminary
groundwater elevation monitoring and mapping conducted by the PRPs in 2008-2009
indicated groundwater flow direction in the vicinity of the Site was
variable. During the July 2008 to
December 2008 monitoring events, groundwater flow appeared to be generally to
the west, with occasional components of flow to the northwest and
southwest.
In 2009 and 2010, the PRPs conducted soil vapor sampling at 9 gas
probes on Site. Soil gas/vapor sampling showed TCE levels greater than the ODH sub-slab TCE screening level of 20 parts
per billion by volume (ppbv), with a high TCE concentration of 10,420 ppbv in
GP20-09.
Operable unit one (OU1)
would involve evaluating cleanup alternatives to address 55 acres of the landfill,
andwould include cleanup alternatives that would allow on-site business to remain
safely operating at the site
The PRPs are also conducting a vapor intrusion study, to evaluate
whether landfill chemicals are posing immediate threats to the on and near-site
businesses. Sampling conducted in
January and March 2012 indicated that TCE and/or methane levels greater than
the ATSDR and ODH TCE sub-slab and indoor air screening levels were observed in
five on-Site non-residential buildings.
In January
and March 2012, the PRPs conducted sub-slab and indoor air sampling at a number
of properties located on-Site and along Dryden and East River Roads. A summary of the analytical results is as
follows:
·
One non-residential building (2003 Dryden Road – Building 2)
showed a sub-slab 1,1-Dichloroethane (1,1-DCA) level greater than the ODH
sub-slab 1,1-DCA screening level of 160 ppbv, with a high 1,1-DCA concentration
of 963 ppbv.
·
Two non-residential buildings (1903 Dryden Road – Building 2 and
2031 Dryden Road – Building 1) showed sub-slab benzene levels greater than the
ODH sub-slab benzene screening level of 20 ppbv, with a high benzene
concentration of 313 ppbv in 2031 Dryden Road.
·
Two non-residential buildings (2015 Dryden Road, Building 1 and
2031 Dryden Road, Building 1) showed sub-slab cis-1,2-DCE levels greater than
the ODH sub-slab cis-1,2-DCE screening level of 370 ppbv, with a high cis-1,2-DCE
concentration of 10,341 ppbv at 2031 Dryden Road, Building 1.
·
Three non-residential buildings (1903 Dryden Road, Building 2;
2003 Dryden Road, Building 2; and 2031 Dryden Road, Building 1) showed sub-slab
vinyl chloride levels greater than the ODH sub-slab vinyl chloride screening
level of 20 ppbv, with a high vinyl chloride concentration of 1,721 ppbv.
·
Thirteen non-residential buildings showed sub-slab TCE levels
greater than the ODH sub-slab TCE screening level of 20 ppbv, with a high TCE
concentration of 5,582 ppbv. Three of
the thirteen non-residential buildings (1951 Dryden Road, 2015 Dryden Road and
2031 Dryden Road) also showed indoor air TCE levels greater than the ODH indoor
air TCE screening level of 2 ppbv, with a high TCE concentration of 13 ppbv,
documenting a Completed Exposure Pathway
for Vapor Intrusion.
·
2031 Dryden Road, Building 1 showed a sub-slab methane level of
0.97% and 1903 Dryden Road, Building 2 showed a sub-slab methane level of 6.6%,
which exceeds the ODH sub-slab methane screening level of 0.5%. Methane is explosive between 5% and 15%.
Table 1 summarizes the four non-residential on-Site buildings
where TCE and methane sub-slab and indoor air screening levels were exceeded.
TABLE 1
SUMMARY OF PRP VAPOR INTRUSION SAMPLING GREATER THAN TCE AND
METHANE SCREENING LEVELS
JANUARY AND MARCH 2012
|
Address
|
Methane
Sub-Slab Screening Level
|
TCE
Screening Levels
(10-5 levels)
|
Dates
Sampled by CRA - January and March 2012
|
|
|
|
Sub-Slab
(in ppbv)
|
Indoor
Air
(in ppbv)
|
Max
Methane in Sub-Slab
|
Max TCE
Sub-Slab
(in ppbv)
|
Max TCE
Indoor Air
(in ppbv)
|
|
|
1903 Dryden Road
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0.5%
|
20
|
2
|
6.6%
|
32
|
ND
|
|
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1951 Dryden Road
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0.5%
|
20
|
2
|
ND
|
2,977
|
13
|
|
|
2015 and 2019 Dryden Road
|
0.5%
|
20
|
2
|
NA
|
5,396
|
5.6
|
|
|
0.5%
|
20
|
2
|
ND
|
5,582
|
3
|
|
|
2031 Dryden Road
|
0.5%
|
20
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2
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0.97%
|
688
|
5.2
|
|
Notes:
Results
bolded and highlighted yellow indicate results exceeding the sub-slab screening
level at the 10-5 Risk Level (Hazard Index of 1.0)
Results
bolded and highlighted red indicate results exceeding the sub-slab screening
level at both the 10-4 and 10-5 Risk Levels.
In order to
obtain seasonal Vapor Intrusion data in July and August 2012, the PRPs
conducted additional sub-slab and indoor air sampling at a number of commercial
and residential properties located on-Site and along Dryden and East River
Roads. A summary of the analytical
results is as follows:
·
One non-residential building (2003 Dryden Road – Building 2)
showed a sub-slab 1,1-DCA level greater than the ODH sub-slab 1,1-DCA screening
level of 160 ppbv, with a 1,1-DCA concentration of 4,100 ppbv.
·
One non-residential building (2003 Dryden Road, Building 2) showed
a sub-slab vinyl chloride level greater than the ODH sub-slab vinyl chloride
screening level of 20 ppbv, with a vinyl chloride concentration of 5,500 ppbv.
·
Seven on-Site non-residential buildings showed sub-slab TCE levels
greater than the ODH sub-slab TCE screening level of 20 ppbv, with a high TCE
concentration of 2,700 ppbv. Two of the
seven non-residential buildings (1901 Dryden Road and 2045 Dryden Road) also showed
indoor air TCE levels greater than the ODH indoor air TCE screening level of 2
ppbv, with a high TCE concentration of 50 ppbv, documenting a completed
exposure pathway for Vapor Intrusion.
This indoor air TCE result is 2.5 times greater than the removal action
screening level provided by ODH. In
addition, one structure on the Valley Asphalt property (Murphy’s Plumbing [MP]
structure) showed an indoor air sample having a PCE concentration of 38 ppbv,
which exceeds the ODH indoor air PCE screening level of 25 ppbv.
·
One on-Site non-residential building (2003 Dryden Road, Building
2) showed sub-slab and indoor air benzene levels greater than the ODH sub-slab
and indoor air benzene levels. The
sub-slab sample (Probe A) showed a benzene concentration of 50 ppbv, which
exceeds the ODH sub-slab benzene screening level of 20 ppbv. The indoor air sample showed a benzene
concentration of 2.4 ppbv, which exceeds the ODH indoor air benzene screening
level of 2 ppbv. The sub-slab and indoor
air sampling results document a completed exposure pathway for Vapor Intrusion.
Table 2 summarizes the three non-residential on-Site buildings
where TCE sub-slab and indoor air screening levels were exceeded.
TABLE 2
SUMMARY OF PRP VAPOR INTRUSION SAMPLING
GREATER THAN TCE SCREENING LEVELS
JULY AND AUGUST 2012
|
Address
|
TCE
Screening Levels
(10-5 levels)
|
Dates
Sampled by CRA –
July
and August 2012
|
|
Sub-Slab
(in ppbv)
|
Indoor
Air
(in ppbv)
|
Max TCE
in Sub-Slab
(in
ppbv)
|
Max TCE
Indoor Air
(in ppbv)
|
|
1901 Dryden Road – Building 1
|
20
|
2
|
2,700
|
8.2
|
|
2045 Dryden Road – Building 1
|
20
|
2
|
1,500
|
50
|
Notes:
Results
bolded and highlighted yellow indicate results exceeding the sub-slab screening
level at the 10-5 Risk Level (or Hazard Index of 1.0)
Results
bolded and highlighted red indicate results exceeding the sub-slab screening
level at both the 10-4 and 10-5 Risk Levels. 10-4 Risk Levels (or Hazard Index
of 10) are 10-times greater than the 10-5 Risk Levels.
Site Background –
Remedial Program Request for Removal Assistance
In a
letter dated June 5, 2012, EPA RPM Karen Cibulskis requested EPA
Emergency Response Branch assistance to determine if the Site met the criteria
for a time-critical removal action. The letter requested removal assistance in evaluating EPA's
options for addressing current and potential vapor intrusion risks at the Site,
including whether Removal authority could be appropriately used to implement
mitigation measures to address all or some of the current and threatened risks
posed by VOCs (primarily TCE) in sub-slab soil gas at 12 commercial/industrial
buildings built over the landfill, and at an adjacent commercial/industrial
building. PRP Vapor intrusion sampling
in January and March 2012 has shown TCE sub-slab vapor levels as high as 5,582
ppbv and TCE indoor air vapor levels as high as 13 ppbv, a documented completed
exposure pathway.
At the occupied building located at 2031 Dryden Road, methane was
detected in a laboratory sub-slab sample at 0.97%, which exceeds the ODH
sub-slab methane screening level of 0.5%.
In Building 2 located at 1903 Dryden Road, which is used for
storage, methane was detected in a laboratory sub-slab sample above 100% of the
LEL (sample concentration 6.6% methane by volume). Building
2 is currently closed to access.
Site Background –
Ohio Department of Health
On
July 6, 2012, the ODH provided health-based guidance to evaluate the results of
Vapor Intrusion sub-slab and indoor air sampling for contaminants of concern at
the Site. ATSDR and ODH identified
residential and non-residential sub-slab and indoor air screening levels. The screening levels are based on 10-5
cancer risk or a Hazard Index of 1.0 and
generally used at remedial sites. ODH
also provided 10-4 screening levels for time-removal action
evaluation. Table 3 summarizes the TCE,
PCE and methane screening levels for the Site.
TABLE 3
2012 OHIO
DEPARTMENT OF HEALTH - TCE, PCE, BENZENE AND METHANE SCREENING LEVELS
|
Chemical of Concern
|
Residential
Screening Level
(10-5)
|
Non-Residential Screening Level
(10-5)
|
Residential
Screening Level
(10-4)
|
Non-Residential Screening Level
(10-4)
|
|
Indoor Air
|
|
TCE
|
0.4
|
2
|
4
|
20
|
|
PCE
|
6
|
25
|
60
|
250
|
|
Benzene
|
0.4
|
2
|
4
|
20
|
|
Methane
|
0.05
|
0.05
|
|
Sub-Slab
|
|
TCE
|
4
|
20
|
40
|
200
|
|
PCE
|
60
|
250
|
600
|
2,500
|
|
Benzene
|
4
|
20
|
40
|
200
|
|
Methane
|
0.5
|
0.5
|
Notes:
The screening levels are in parts
per billion by volume (ppbv) and based on 10-5 cancer risk (Hazard
Index of 1.0) and based on a 10-4 cancer risk (Hazard Index of 10).
Site Background –
Ohio EPA Request for Removal Assistance
In a letter dated July 17, 2012, the Ohio EPA expressed
concerns about the risk to human health from indoor air exposure to VOCs and
the risk of explosive conditions from landfill gas. Ohio EPA views the Site as a threat to the
on-Site and surrounding businesses and residences, and supports the Remedial
branch’s request for assistance from the Removal branch in evaluating options
for addressing current and potential vapor intrusion risks at the SDDL Site.
1.1.2.1 Location
The
Site is located at 1901 through 2153 Dryden Road and 2225 East River Road in
Moraine, Ohio. The Site’s geographic
coordinates (based on the address of 1975 Dryden Road) are 39° 43’ 42.6354”
North latitude and 84° 12’ 59.8278” West longitude. The Site is bounded to the north and west by
the Miami Conservancy District floodway (part of which is included in the
definition of the Site), the Great Miami River Recreational Trail and the Great
Miami River beyond. The Site is bounded
to the east by Dryden Road with light industrial facilities beyond, to the
southeast by residential and commercial properties along East River Road with a
residential trailer park beyond, and to the south by undeveloped land with industrial
facilities beyond.
Approximately
25,060 people live within a 4-mile radius of the Site. Six single-family residences are located on
the northwest side of East River Road and are adjacent to the southeast
boundary of the Site. A seventh single
family home is located on the southeast side of East River Road and is within
300 feet of the Site. A trailer park
with several residences is also situated approximately 300 feet southeast of
the Site at the southeast intersection of Dryden Road and East River Road.
Part of the landfill is within the 100 year
floodway and more than half of the landfill is within the 100 year
floodplain. The landfill is within a
secondary wellhead protection area and there is a well (not used for drinking
water) in the northern part of the landfill.
The Site also contains a federally designated wetland. Some of the landfilled materials are below
the water table and are in direct contact with groundwater.
1.1.2.2 Description of Threat
A
release of hazardous substances, pollutants, or contaminants is present due to
documented vapor intrusion at the SDDL Site.
A completed exposure pathway exists for vapor intrusion, as TCE has been
documented in the groundwater (TCE as high as 260 ppb), in the soil gas (TCE as
high as 10,420 ppbv), in the sub-slab (TCE as high as 17,000 ppbv) and in the
indoor air (TCE as high as 50 ppbv).
Vapor intrusion is occurring at the Site.
In
addition, a second completed exposure pathway exists for vapor intrusion, as
benzene has been documented in the sub-slab (at 50 ppbv) and in the indoor air
(at 2.4 ppbv) at one on-Site non-residential property.
Sub-slab
sampling has documented a methane level of 6.6% in one non-residential property
on Site. Methane is explosive between 5%
and 15%.
1.1.3 Preliminary Removal Assessment/Removal Site Inspection Results
Between July 12 and August 8, 2012, EPA conducted a Removal Site Investigation at the Site including residential
and non-residential sub-slab sampling and the installation of soil gas vapor
probes along the Site’s eastern perimeter.
Sub-Slab Samples
EPA collected sub-slab samples at
three residential and five non-residential buildings. The results of the sampling are as follows:
· EPA observed PCE in sub-slab samples collected from the three residential
properties (2391, 2232 and 2373 East River Road) at concentrations ranging from
7.7 to 20 ppbv, which are less than the ODH residential sub-slab PCE screening
level of 60 ppbv.
·
Sub-slab
samples collected from non-residential properties located at 2230 and 2205
Dryden Road did not detect TCE at concentrations greater than the ODH sub-slab
TCE screening level of 20 ppbv. PCE was
detected in one sub-slab sample collected from 2205 Dryden Road at a
concentration of 110 ppbv, which is less than the non-residential sub-slab PCE
screening level of 250 ppbv.
·
1951
Dryden Road (Building 1, Probe D) – EPA observed a TCE sub-slab
concentration of 2,900 ppbv, which exceeds the ODH sub-slab TCE screening level
of 20 ppbv.
·
2031
Dryden Road (Building 1, Probe C) – EPA observed a cis-1,2-DCE sub-slab
concentration of 27,000 ppbv, which exceeds the ODH sub-slab cis-1,2-DCE
screening level of 370 ppbv; a benzene sub-slab concentration of 540 ppbv,
which exceeds the benzene screening level of 20 ppbv; a TCE sub-slab
concentration of 460 ppbv, which exceeds the TCE screening level of 20 ppbv; a
m,p-xylene sub-slab concentration of 2,100 ppbv, which exceeds the m,p-xylene
screening level of 2,000 ppbv; an o-xylene sub-slab concentration of 2,000
ppbv, which equals the o-xylene screening level of 2,000 ppbv; and a vinyl
chloride concentration of 2,600 ppbv, which exceeds the vinyl chloride
screening level of 20 ppbv. In addition,
methane was detected in the sub-slab sample at a concentration of 2.2%, which
exceeds the ODH sub-slab methane screening level of 0.5%.
·
2015
Dryden Road (S&J Building, Probe B) – EPA observed a cis-1,2-DCE
sub-slab concentration of 1,400 ppbv, which exceeds the ODH sub-slab
cis-1,2-DCE screening level of 370 ppbv.
TCE was observed in the sub-slab air sample at a concentration of 17,000
ppbv, which exceeds the TCE sub-slab screening level of 20 ppbv.
Table 4 summarizes the sub-slab data
having sub-slab exceedances.
TABLE 4
SUMMARY OF 2012 EPA SUB-SLAB
EXCEEDANCES
|
Compound
|
Sub-Slab Screening Level
(10-5 Risk Level for Non-Residential Locations)
|
Sample ID
|
1951 Dryden-SS-080712
|
2031 Dryden-SS-080712
|
2015 Dryden-SS-080812
|
|
Address
|
1951 Dryden Road
Probe D
(Building 1)
|
2031 Dryden Road
Probe C
|
2015 Dryden Road
Probe B
(S&J Building)
|
|
Date Sampled
|
8/7/2012
|
8/7/2012
|
8/8/2012
|
|
cis-1,2-Dichloroethylene
|
370
|
|
52
|
27,000
|
1,400
|
|
Benzene
|
20
|
|
ND (11)
|
540
|
ND (28)
|
|
Trichloroethylene
|
20
|
|
2,900
|
460
|
17,000
|
|
m,p-Xylene
|
2,000
|
|
ND (11)
|
2,100
|
ND (28)
|
|
o-Xylene
|
2,000
|
|
ND (11)
|
2,000
|
ND (28)
|
|
Vinyl Chloride
|
20
|
|
ND (11)
|
2,600
|
ND (28)
|
|
Percent Methane
|
0.5%
|
|
0.00037%
|
2.2
|
0.00045%
|
|
Notes:
Results
reported in parts per billion by volume, except for percent methane.
Results bolded and highlighted yellow
indicate results exceeding the sub-slab screening level at the 10-5
Risk Level (Hazard Index of 1.0)
Results bolded and highlighted red
indicate results exceeding the sub-slab screening level at both the 10-4
and 10-5 Risk Levels. 10-4
Risk Levels (Hazard Index of 10) are 10-times greater than 10-5
Risk Levels.
ND = Not
detected at method reporting limit
|
Soil Gas Samples
EPA used a Geoprobe unit and
installed soil gas probes at nested depths between 8-feet and 16-feet below
ground surface (bgs) at four locations (GP-3, GP-4, GP-6 and GP-7) on the west
side of Dryden Road, two locations (GP-2 and GP-5 on City of Moraine property)
on the east side of Dryden Road and one location (GP-1) adjacent to the
property located at 2233 East River Road.
From July 24 through 27, 2012, EPA
conducted field screening at each soil gas probe for VOCs (using a Multi-RAE
photoionization detector [PID]) and percent methane (GEM2000 methane
meter). EPA observed detectable
methane concentrations in soil gas probe GP-2.
The 12-foot bgs nested soil gas probe showed methane levels ranging from
14.7% to 17.6%. The GP-2 soil gas probe
at the 16-foot depth showed methane levels ranging from 22.2% to 24.1%.
On July 30, 2012, grab samples were
collected and analyzed for methane and VOCs (using Method TO-15) from five of
the soil gas probe depths. The following is a summary of the soil gas
probe sampling results:
·
The
soil gas sample collected at GP-2 (16-feet bgs) showed the following VOC
concentrations: 2,2,4-trimethylpentane at 14,000 ppbv, hexane at 12,000 ppbv
and heptane at 860 ppbv. In addition,
methane was detected at 2.5%.
·
The
soil gas sample collected at GP-3 (8-feet bgs) showed a TCE concentration of
120 ppbv, which exceeds the ODH sub-slab TCE screening level of 20 bgs.
·
The
soil gas sample collected at GP-4 (16-feet bgs) showed a TCE concentration of
49 ppbv, which exceeds the ODH sub-slab TCE screening level of 20 bgs.
·
The
soil gas sample collected at GP-6 (12-feet bgs) showed a TCE concentration of
41 ppbv, which exceeds the ODH sub-slab TCE screening level of 20 bgs.
|
|
|
|
2.1.1 Narrative
Vapor
intrusion sampling results from 2012 by EPA and the PRPs have documented
vapor intrusion is occurring at the Site.
Five non-residential buildings have shown sub-slab TCE concentrations
greater than the ODH sub-slab screening level (as high as 17,000 ppbv) and
indoor air TCE concentrations greater than the ODH indoor air screening level
of 2 ppbv (as high as 50 ppbv). One
non-residential building has shown a sub-slab benzene concentration (50 ppbv)
greater than the ODH sub-slab screening level (20 ppbv) and an indoor air
benzene concentration (2.4 ppbv) greater than the ODH screening level (2
ppbv). One non-residential building has
shown a crawl space PCE concentration at 38 ppbv which exceeds the ODH indoor
air PCE screening level of 25 ppbv.
Vapor intrusion has been documented to be occurring at this Site. In addition, one non-residential building has
shown a sub-slab methane level of 6.6%.
Methane is explosive between 5% and 15%.
EPA has documented methane levels using field
screening and soil gas samples in GP-2 (12-foot and 16-foot depths) ranging
from 2.5% to 24.1%. These results are
greater than the ODH sub-slab methane screening level of 0.5% and Ohio EPA’s
perimeter regulatory level of 5% (lower explosive limit). GP-2 is located off-Site, on the eastside of
Dryden Road and adjacent to a DP&L building.
For purposes of managing the time-critical removal action, the Site will be segregated into 2 operating units.
Operating Unit 3 (OU3) will encompass removal work south of the Valley Asphalt Corporation property.
Operating Unit 4 (OU4) will encompass removal work on the Valley Asphalt Corporation property.
2.1.2 Response Actions to Date
OU3 work:
On January 3, 10, 17, 24 and 31, 2013, EPA, Ohio EPA, START and the Respondents participated in conference calls regarding EPA requirements for vapor intrusion (VI) mitigation. EPA OSC holding weekly meetings to begin technical discussions on what will need to be included in the Work Plan. Conestoga-Rovers & Associates (CRA) is the primary environmental consultant for the Respondents.
On January 9 and 10, 2013, the Respondents completed confirmatory sampling of buildings with indoor air benzene and chloroform issues. This re-sampling was to confirm the sampling results from the Respondent's August 2012 sample results.
On January 10 and 11, 2013, the Respondents provided EPA with comments on a sub-slab depressurization system (SSDS) acceptance letter and estimated electricity cost for SSDS operation, respectively.
On January 10, 17 and 24, 2013, the Respondents provided EPA with draft sections of the VI Mitigation Work Plan for review.
On January 24, 2013, the Respondents installed Model 2001 Sierra Gas Monitor at 1903 Dryden Road (Valley Asphalt, Building 2, Parcel 5054).
On January 31, 2013, the Respondents installed Model 2001 Sierra Gas Monitor at 2031 Dryden Road (SIM Trainer Building 15, Parcel 5173).
On February 7, 14, 21 and 28, 2013, EPA, Ohio EPA, START and the Respondents participated in conference calls regarding EPA requirements for VI mitigation.
On February 15, 2013, EPA provided the Respondents with comments on the draft VI Mitigation Work Plan.
On March 1, 2013, the Respondents signed and submitted to EPA an Administrative Settlement Agreement and Order on Consent (ASAOC). The ASAOC stated that the Responding Parties have agreed to conduct vapor intrusion work at the SDDL Site, except for work on the Valley Asphalt Corporation property.
On March 7, 14 and 28, 2013, EPA, Ohio EPA, START and the Respondents participated in conference
calls regarding updates to the status of the VI mitigation. The
Respondents provided meeting minutes for each conference call.
On March 15, 2013, CRA completed visits to the eight buildings proposed for VI mitigation. CRA was accompanied by prospective Ohio licensed radon contractors. The purpose of the building visits was to gather information that would aid in the design of sub-slab depressurization systems and help the Respondents finalize the contractor selection.
On March 28, 2013, the Respondents provided EPA with a revised draft VI Mitigation Work Plan for review.
On April 4, 11, 18 and 25, 2013, EPA, Ohio EPA, START and the Respondents participated in conference
calls regarding updates to the status of the VI mitigation. The
Respondents provided meeting minutes for each conference call.
On April 5, 2013, EPA executed the Removal Action ASAOC. Based on the dates of the Return Receipts, the effective date of the Removal Action ASAOC was April 8, 2013.
On April 12, 2013, the Respondents formally notified EPA in a letter indicating that CRA would be the primary environmental consultant for the removal action and Adam Loney (CRA) would be the project coordinator at the Site.
On April 29, 2013, CRA submitted a draft VI Mitigation Work Plan for EPA to review.
On May 1, 2013, EPA OSC issued a conditional approval letter to the Respondents for the VI Mitigation Work Plan based on EPA modifications.
On May 2, 9, 16, 23 and 30, 2013, EPA, Ohio EPA, START and the Respondents participated in conference calls regarding the status of VI mitigation activities.
On May 9, 2013, the Respondents issued an electronic copy and sent out hard copies of the Final VI Mitigation Work Plan to EPA.
On May 13, 2013, the Respondents issued a letter to EPA identifying the properties where access has or has not been obtained.
On May 13, 2013, START, CRA, CRA's SSDS installation subcontractor (Environmental Doctor) held a meeting with Globe Equipment regarding the proposed SSDS installation.
On June 6, 13, 20 and 27, 2013, EPA, Ohio EPA, START and the
Respondents participated in conference calls regarding the status of VI
mitigation activities.
On June 13, 2013, the Respondents provided EPA, Ohio EPA, Public Health - Dayton and Montgomery County (PHDMC) with revised figures showing proposed SSDS compliance and extraction point locations; the Respondents also included a list of proposed changes to the proposed locations due to existing sub-slab soil vapor probe locations.
On June 18, 2013, the Respondents provided copies of the signed Vapor Abatement System Acceptance Forms for the 8 buildings addressed by the VI Mitigation Work Plan.
On June 20, 2013, CRA began SSDS installation activities at 2215 East River Road (Building 24 - Globe Equipment). Estimated completion date was set at July 24, 2013.
On June 28, 2013, CRA began SSDS installation activities at 1951 Dryden Road (Building 8 - B&G Equipment). Estimated completion date was set at July 24, 2013.
OU4 work:
On March 22, 2013, EPA issued a Unilateral Administrative Order (UAO) to
the Valley Asphalt Corporation for Removal Actions at the Valley
Asphalt Site. The UAO effective date was April 16, 2013.
On April 19, 2013, the Respondent (Valley Asphalt Corporation) formally notified EPA that it would comply with the UAO.
On April 22, 2013, the Respondent formally notified EPA that Bowser-Morner would be the primary environmental contractor at the Site, and that Katherine Beach (Bowser-Morner) would be the project coordinator.
On April 26, 2013, the Respondent submitted a draft VI Mitigation Work Plan to mitigate the 6 buildings on the Valley Asphalt property.
On June 6, 2013, a conference call was conducted between EPA, Ohio EPA, START, and the Respondent to discuss the VI mitigation work plan. The Respondent initial plans to mitigate 3 properties and to demolish 4 properties. One of the properties (Building 2) will be partially demolished and the portion not demolished will have a SSDS installed. The Respondent stated that the Environmental Doctor will be installing the SSDSs on site.
On June 11, 2013, Respondent installed sub-slab probes in the 3 buildings where SSDSs will be installed in order to measure vacuum once the systems are installed.
On June 13, 2013, a conference call was conducted between EPA, Ohio EPA, START, and the Respondent to discuss the VI mitigation work plan. The SSDS for Building 2 was scheduled to begin on July 8, 2013. The Respondents sent out preliminary SSDS designs for the three buildings to get mitigated. EPA provided comments to sub-slab and compliance probe locations.
On June 20, 2013, a conference call was conducted between EPA, Ohio EPA, START, and the Respondent to discuss the VI mitigation work plan. The Respondent stated that due to the cost of the SSDS installation and long-term sampling and monitoring for each building, that it might be more cost effective for them to demolish the buildings that are not important to the operation of the facility. The Respondent stated that it will demolish Buildings 1, 2 (partial), 7 and the MP Building. The Respondent plans to install a SSDS in Buildings 2 (partial), 4 and 5.
On June 27, 2013, a conference call was conducted between EPA, Ohio EPA, START, and the Respondent to discuss the VI mitigation work plan. After further review of the cost to install an SSDS and the monitoring involved following install, the Respondent stated that it would be more cost effective for them to demolish Buildings 2 and 5. The only building that will have a SSDS will be Building 4. Lead and asbestos surveys to be completed in all buildings where demolition will take place.
On July 10, 2013, an SSDS was installed in Building 4. One extraction point was installed in the building. Radius of influence testing was completed and proved that there is a vacuum reaching across the floor of the building.
2.1.3 Enforcement Activities, Identity of Potentially Responsible Parties (PRPs)
There are two groups of PRPs at the SDDL Site conducting removal activities.
Operable Unit 3 (OU3)
Hobart Corporation
NCR Corporation
Kelsey Hayes Company
(CRA is the environmental consultant)
Operable Unit 4 (OU4)
Valley Asphalt Corporation
(Bowser-Morner is the environmental consultant)
2.1.4 Progress Metrics
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Manifest # |
Treatment |
Disposal |
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