HomeMy WebLinkAboutFUEL SYST_June 2012 Vapor Intrusion Report-OCR
VAPOR INTRUSION
REPORT
Former Fuel Systems Facility
5019 Hovis Road
Charlotte, NC
Prepared For:
BorgWarner Inc.
Auburn Hills, MI
June 2012
AIR QUALITY
HYDROGEOLOGY
ANALYTICAL LABORATORY
REGULATORY COMPLIANCE
CIVIL & ENVIRONMENTAL ENGINEERING
Vapor Intrusion Report
Former Fuel Systems Facility, Charlotte, North Carolina
June 2012
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TABLE OF CONTENTS
Page
1.0 INTRODUCTION .............................................................................................................. 1
1.1 SITE INFORMATION ........................................................................................................... 1
1.2 PURPOSE ........................................................................................................................... 1
2.0 FIELD INVESTIGATION ..................................................................................................... 2
2.1 QUALITY ASSURANCE/QUALITY CONTROL SAMPLES ....................................................... 3
2.2 LABORATORY ANALYSIS .................................................................................................... 3
3.0 RESULTS AND RECOMMENDATIONS ................................................................................ 3
3.1 VAPOR INTRUSION RESULTS ............................................................................................. 4
3.2 CALCULATION OF WORST CASE 1,1-DCE CONCENTRATION ............................................. 4
3.3 RECOMMENDATION ......................................................................................................... 6
4.0 REFERENCES ................................................................................................................... 7
FIGURES
Figure 1 ................................................................................................................ Site Location Map
Figure 2 ....................................................................................................... Soil Gas Sample Results
Figure 3 ................................................................................................ Indoor Air Sample Locations
TABLES
Table 1 ......................................................................................... Sample Collection Field Summary
Table 2 .................................................... Indoor/Outdoor Temperatures during Sample Collection
Table 3 .................................................................................................. Indoor Air Analytical Results
APPENDICES
Appendix A .................................................................................................................... Photographs
Appendix B ........................... Analytical Laboratory Reports and Chain of Custody Documentation
Appendix C ........................................................ Worst Case Indoor Air Concentration Calculations
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June 2012
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ACRONYM LIST
ASHRAE American Society of Heating, Refrigerating, and Air Conditioning
Engineers
1,1-DCE 1,1-dichloroethene
° F degrees Fahrenheit
FD field duplicate
ft feet
IHSB Inactive Hazardous Sites Branch
K Kelvin
Kysor Kysor/Michigan Fleet Division
m2 square meters
m3/s cubic meters per second
µg/m3 micrograms per cubic meter
NCDENR North Carolina Department of Environment and Natural Resources
NRCS Natural Resources Conservation Service
PID photoionization detector
ppm parts per million
QA quality assurance
QC quality control
SCAN Soil Climate Analysis Network
USDA U.S. Department of Agriculture
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June 2012
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1.0 INTRODUCTION
This report presents the results of indoor air sampling conducted at the Former Fuel Systems
Facility, located at 5019 Hovis Road in Charlotte, North Carolina (the Site), on May 3, 2012. This
investigation was conducted due to detections of 1,1-dichloroethene (1,1-DCE) in subsurface
soil gas samples collected at the Site in October 2011, and reported in the Vapor Intrusion and
Soil Sampling Report (Rogers & Callcott, 2011). This investigation was completed in accordance
with the Work Plan for Vapor Intrusion Sampling (Rogers & Callcott, 2012).
1.1 SITE INFORMATION
Prior to its recent purchase from a bankruptcy trustee by Hovis LLC in December 2010, the Site
was owned and operated by Fuel Systems LLC. Fuel Systems and the former owner,
Kysor/Michigan Fleet Division (Kysor), operated the facility for manufacturing and warehousing
fuel tanks for commercial and military transport trucks. The manufacturing processes included
shaping and welding sheet aluminum and steel into fuel tanks, cleaning and degreasing tank
components using chlorinated and aromatic solvents, acid etching of aluminum tanks, spray
painting of tanks, and installation of instrumentation (Ogden, 1997). The finished tanks were
stored in the facility prior to shipping.
The property consists of 3.94 acres and includes a single story, industrial building that covers
approximately 55% of the Site property. The building appears to be constructed predominantly
of steel framing and masonry walls with concrete floors (slab on grade) and a steel framed tar
and gravel roof. The Site is located in the northwest portion of the Charlotte city limits within
an older industrial park. The area has been assigned an I-2 zoning classification (i.e., General
Industrial).
The Site is bounded by Hovis Road along its eastern property boundary and by Bealer Road
along its northern property boundary. Sets of both active and decommissioned railroad tracks
owned by CSX bound the property to the west. Constar International, a manufacturer of plastic
drink bottles, occupies the adjacent property to the south. A Site location map is provided as
Figure 1.
1.2 PURPOSE
The potential for vapor intrusion of 1,1-DCE was evaluated through sampling of the subsurface
soil gas just above each of the two groundwater plumes identified in previous investigations
based on screening against the Acceptable Groundwater Concentrations provided in the IHSB
Industrial/Commercial Vapor Intrusion Screening Tables. Within the plume identified to the
south of the facility, two soil gas samples (SG-6 and SG-7) exceeded the Acceptable Soil Gas
Concentration for 1,1-DCE of 1,760 µg/m3. Soil gas sample locations and 1,1-DCE results are
summarized on Figure 2. As shown in the referenced figure, SG-6 was the only soil gas sample
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located adjacent to the facility that exceeded the screening level. Consequently, this
investigation concentrated on sampling the area of the facility interior adjacent to sample
location SG-6.
This report presents the indoor air sample data collected during the May 3, 2012 sampling
event. Sample results were compared to the 1,1-DCE Acceptable Indoor Air Concentration of
176 μg/m3 provided in the February 2012 IHSB Vapor Intrusion Screening Tables. Due to
temperatures above the optimal ambient air temperature recommended by the NC
Department of Environment and Natural Resources (NCDENR) guidance (NCDENR, 2011), the
sample results were also used to calculate the maximum possible 1,1-DCE indoor air
concentrations under the recommended sampling conditions.
2.0 FIELD INVESTIGATION
Sampling activities were conducted at the Site on May 3, 2012, as soon as possible after some
potential indoor air contaminant sources were removed by the owner, and following two Site
visits conducted in January and March 2012. Potential sources removed from the facility
included the drums of used oil adjacent to a former machine pit. The pit was partially filled with
soil after the January Site visit. The pit was still partially filled and not capped at the time of
sample collection, but the fill soil had been covered with plastic sheeting. Some solvent
containers (mineral spirits and WD-40) and several vehicles were still present in the facility.
Photographs of the facility interior during sampling activities are provided as Appendix A.
Sample collection began just before sunrise when exterior temperatures are typically coolest,
and therefore the atmospheric conditions closest to those recommended by NCDENR guidance
(average high temperatures less than 60° F). A total of five samples, including one field
duplicate, were collected at the Site. All samples were collected into evacuated stainless steel
6-Liter Summa canisters. Flow regulators were used to collect the samples over a 4-hour period.
As specified in the NCDENR guidance document, collection of an exterior background sample
(BWIA-1) began approximately one hour before collection of the indoor air samples began.
Prior to collection of the indoor samples, the interior of the facility was screened by a
photoionization detector (PID) to determine the most likely potential source areas of
background contamination. PID readings ranged from 1.8 to 5.2 parts per million (ppm)
throughout the facility with the highest readings occurring in the northwest corner of the room
located at the northeast corner of the facility. The lowest readings occurred in the southern
portion of the facility in the area adjacent to SG-6. The area of the machine pit along the
western wall of the facility exhibited PID readings ranging from 2.5 to 3.6 ppm.
A total of five samples were collected at the locations shown on Figure 3. Sample BWIA-1 was
collected as an exterior background sample, located outside the main entrance of the facility
along Hovis Road. Sample BWIA-2 was located in the area of highest PID readings (Photos 1 and
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2, Appendix A), sample BWIA-3 was located near the northeast corner of the machine pit
(Photos 3 and 4, Appendix A), and BWIA-4 plus a field duplicate, BWIA-5, were located along
the southern wall of the facility adjacent to soil gas sample location SG-6 (Photos 11-13,
Appendix A). Table 1 provides sample IDs, sample locations, start and end times for sample
collection, and the approximate PID reading or range measured at each sample location.
Ambient air temperatures were measured every hour at interior sample location BWIA-4/5 and
exterior sample location BWIA-1 during collection. Temperature measurements are
summarized in Table 2. The average exterior temperature was 73.7° F during sampling, and
ranged from 66.4° F when sampling began to 81.8° F when sampling was completed. Interior
temperatures remained relatively stable during sample activities, with an average temperature
of 74.6° F, rising slightly from 74.0° F when sampling began to a maximum of 75.4° F.
2.1 QUALITY ASSURANCE/QUALITY CONTROL SAMPLES
Three quality assurance/quality control (QA/QC) samples were collected during the indoor air
investigation. As noted above, BWIA-5 was collected as a duplicate of sample BWIA-4. The two
samples were collected simultaneously by attaching the legs of a Swagelok® “T” to two flow
regulators and SUMMA canisters (Photo 13, Appendix A). The duplicate sample provided
information on the consistency and reproducibility of the field sampling and analytical
procedures. The background sample (BWIA-1) was collected in an upwind position outside of
the building to monitor any exterior background levels of 1,1-DCE in the investigation area.
Additionally, a trip blank (BWIA-Trip Blank) was submitted for analysis. The trip blank canister
remained unopened, but accompanied the other canisters during transport from the Site to the
laboratory, thus experiencing the same storage, shipping, and analysis conditions. The trip
blank provided information on the field and laboratory sample handling procedures as well as
sample integrity during shipping. The laboratory analyzed additional internal QA/QC samples at
the time of sample analysis consisting of a laboratory blank, a continuing calibration verification
sample, a laboratory control spike, and a laboratory control spike duplicate.
2.2 LABORATORY ANALYSIS
Samples were shipped to Air Toxics Ltd. in Folsom, CA, where they were analyzed for 1,1-DCE
by Modified EPA Method TO-15 (5 & 20 ppbv). Chain of custody documentation for the indoor
air samples is included along with the laboratory reports in Appendix B.
3.0 RESULTS AND RECOMMENDATIONS
The following subsections provide a discussion of the results generated from the indoor air
investigation, a summary of methods used to calculate the maximum possible indoor air
concentrations of 1,1-DCE during worst case conditions, and recommendations regarding the
overall vapor intrusion assessment for the Site.
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3.1 VAPOR INTRUSION RESULTS
1,1-DCE concentrations for indoor air samples including QA/QC samples are summarized in
Table 3. Concentrations in all indoor air samples were below detection. The reporting limit
ranged from 38 to 39 micrograms per cubic meter (μg/m3) for samples BWIA-1 – BWIA-5. This
reporting limit range is well below the Acceptable Indoor Air Concentration of 176 μg/m3 for
1,1-DCE listed in the IHSB Vapor Intrusion Screening Tables (February, 2012).
All QA/QC samples support the validity of the results. The trip blank and background samples
had no detectable concentrations. Sample BWIA-4 and its field duplicate also exhibited no
detectable concentrations.
Additionally, all laboratory control samples met the laboratory’s QC requirements. No receiving
or analytical discrepancies were noted in the laboratory report (Appendix B). The laboratory
control blank had a non-detectable concentration of 1,1-DCE, and the continuing calibration
verification sample, laboratory control sample, and laboratory control sample duplicate all
exhibited percentage recoveries that were within the acceptable method limits. Also, surrogate
percentage recovery values met the method limits in all samples analyzed.
3.2 CALCULATION OF WORST CASE 1,1-DCE CONCENTRATION
As previously noted, indoor air samples were collected when the average exterior temperature
was above the optimal average high of 60° F. Exterior temperatures were greater than the
interior temperatures for approximately 2 hours over the 4 hours during which the indoor air
samples were collected. During the winter, when exterior temperatures decrease, the soil
located beneath the building slab is cooled, thereby increasing the pressure gradient between
the subsurface soil gas and the building interior. When such a pressure differential occurs,
advection of vapors from the subsurface to the indoor air will increase. This negative pressure
effect typically associated with indoor heating is known as the chimney or stack effect
(McHugh, 2006). This pressure gradient can also be affected by air intake and exhaust rates
associated with central heating, ventilation, and air conditioning systems and dehumidification
of indoor air. Because indoor air in the main portion of the Site facility where sampling was
conducted is not currently conditioned, pressure gradients between the subsurface and the
building interior were assumed to be entirely due to the temperature difference between the
subslab soil gas and indoor air. The calculations presented below were used to determine the
potential increase in vapor advection during the winter months as compared with the data
collected in May.
The advective flow rate due to the temperature difference between two adjoining volumes can
be calculated based on the following equation [American Society of Heating, Refrigeration, and
Air-Conditioning Engineers (ASHRAE), 1997]:
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Where:
Q = the advective flow rate (m3/s)
C = discharge coefficient (typically 0.65 – 0.70)
A = flow area between two volumes (m2)
g = gravitational acceleration (9.81 m/s2)
h = building height (ft)
Ti = average indoor air temperature (K)
Ts = average air temperature of subslab soil (K)
Because the gravity, building height, flow area (i.e. – area of cracks in the slab through which
vapor flow could occurs), and the discharge coefficients are constant throughout the year, the
above equation can be used to determine the ratio between the advective flow rate into the
building from the subsurface under worst case conditions (in winter months) and during the
May sampling event (Qw/Q) as follows:
Where:
Qw = the advective flow rate during worst case conditions (m3/s)
Tiw = average indoor air temperature during worst case conditions (K)
Tsw = average air temperature of subslab soil during worst case conditions (K)
Complete derivation of this equation and the calculation of Qw/Q are provided in Appendix C.
To calculate Qw/Q , the following input values were used:
Ti = 296.61 K Calculated as the average indoor air temperature measured at the Site over the
sampling period.
Ts = 295.10 K Calculated as the average of hourly soil temperatures measured at a depth of 4
inches during the sampling period on May 3, 2012, at a Soil Climate Analysis
Network (SCAN) site operated by U.S. Department of Agriculture (USDA) –
Natural Resources Conservation Service (NRCS) near the town of Critz, VA.
Tsw = 275.66 K Calculated as the average of hourly soil temperatures measured at a depth of 4
inches on January 19, 2012, over the same sampling period and at the same
NRCS monitoring station.
Tiw = 288.56 K Estimated to be a maximum of 60° F based on January 19, 2012 Site visit.
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Temperatures from January 19, 2012, were selected for the worst case calculation as outdoor
air temperatures in Charlotte, NC (mean T = 38.3° F) and Critz, VA (mean T = 34.7° F) were
under the threshold temperature for indoor air sampling of 60° F. Additionally, this was the
date of the initial January Site visit. Although an indoor air temperature was not measured at
the Site during the visit, the building was unheated, and Tiw was conservatively estimated to be
a maximum of 60° F.
Using the preceding input values, the flow rate ratio Qw/Q is found to be 2.96, which means
that the air volume migrating from the subslab soil gas to the building interior was 2.96 times
lower during the sampling period on May 3, 2012 than over the same time period on January
19, 2012. From the calculated flow rate ratio, the maximum possible 1,1-DCE concentration
calculated for worst case conditions is 113 μg/m3, which is approximately 64% of the
Acceptable Indoor Air Concentration of 176 μg/m3 for 1,1-DCE. This calculation makes the
following conservative assumptions:
• Indoor air temperature was 60° F on January 19, 2012.
• The 1,1-DCE soil gas concentration is constant, which is considered a conservative
estimate as the 1,1-DCE in groundwater will partition to the soil gas to a lesser extent
during colder (worst case) conditions.
• The entire mass of 1,1-DCE accumulates in the building, which again is a conservative
estimate as some of the 1,1-DCE entering the building likely would diffuse through holes
or vents in the roof of the building.
• An indoor air concentration of 1,1-DCE just below the reporting limit of 38 μg/m3 at
BWIA-4/5, which is a conservative assumption as the analytical laboratory indicated that
the 1,1-DCE concentration was below the method detection limit (MDL) of 5 μg/m3 in all
samples based on a visual review of the sample chromatograms.
Using the same calculation method and assuming a 1,1-DCE concentration at the MDL of 5
μg/m3, the resulting worst case concentration is less than 15 μg/m3, which is approximately
8.5% of the Acceptable Indoor Air Concentration.
3.3 RECOMMENDATION
Based on the results of the indoor air investigation and subsequent calculations, it was
determined that:
• 1,1-DCE was not detected in any of the samples.
• Calculations demonstrate that sampling outside of the optimal temperature conditions
had no impact on the findings.
Therefore, no further action is warranted.
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4.0 REFERENCES
ASHRAE, 1997. ASHRAE Fundamentals Handbook. Atlanta, GA: American Society of Heating,
Refrigerating and Air-Conditioning Engineers, Inc.
NCDENR, 2011b. Supplemental Guidelines for the Evaluation of Structural Vapor Intrusion
Potential for Site Assessments and Remedial Actions under the Inactive Hazardous Sites
Branch and Industrial/Commercial Vapor Intrusion Screening Tables (August 2011).
Division of Waste Management: Superfund Section: Inactive Hazardous Sites Branch.
Ogden Environmental and Engineering Services Co, Inc., January 1997. Preliminary Site
Assessment Report: KYSOR/Michigan Fleet Division.
Rogers & Callcott, 2011. Vapor Intrusion and Soil Sampling Report, Former Fuel Systems Facility,
Charlotte, North Carolina.
Rogers & Callcott, 2012. Work Plan for Vapor Intrusion Sampling, Former Fuel Systems Facility,
Charlotte, North Carolina.
USDA – NRCS, 2012. National Water and Climate Center website: Soil Climate Analysis Network,
1 Jun 2012. http://www.wcc.nrcs.usda.gov/scan/.
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FIGURES
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FIGURE 1
5019 Hovis Road,Charlotte, NC 28208
SITE LOCATIONMAP
FUEL SYSTEMS FACILITY
.
REFERENCE:
North Carolina One Map, 2010 aerial photography. MecklenburgCounty GIS, propperty boundary.
SITE
Approximate Site Boundary
!A
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SG-3 SG-2
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MW-6
MW-7
MW-5MW-4
MW-9
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FIGURE 2
5019 Hovis Road,Charlotte, NC 28208
SOIL GASSAMPLE RESULTS
FUEL SYSTEMS FACILITY
.
REFERENCE:North Carolina One Map, 2010 aerial photography.Mecklenburg County GIS, property boundary.Comprehensive Site Assessment Addendum, 2000 andAdditional Groundwater Assessment Report, 2008.
!A Monitoring Wells
Approximate Site Boundary
!(Soil Gas Sample
(ND for 1,1-DCE)
!(
Soil Gas Sample
(Exceeds Acceptable Soil
Gas Concentration)
Acceptable soil gas concentration for 1,1-DCE = 1,760 ug/m3
(NCDENR IHSB Industrial Vapor Intrusion Screening Table)
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BWIA-2
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FIGURE 3
5019 Hovis Road,Charlotte, NC 28208
INDOOR AIRSAMPLE LOCATIONS
FUEL SYSTEMS FACILITY
.
REFERENCE:
North Carolina One Map, 2010 aerial photography.Mecklenburg County GIS, property boundary.Comprehensive Site Assessment Addendum, 2000 andAdditional Groundwater Assessment Report, 2008.
!?Indoor Air Sample Location
!(Soil Gas Sample Location
!A Monitoring Wells
Approximate Site Boundary
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TABLES
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NC
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TimePID Reading (ppm)
BW
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1
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:
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:
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AM
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.
8
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BW
I
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.
5
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I
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ll
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11
:
2
5
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1
.
8
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F
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l
d
Du
p
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1
1
:
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5
AM
1
.
8
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9
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P
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6
‐1 ‐12
Rogers & Callcott Engineers, Inc.
Ta
b
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In
d
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0
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3
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.
7
8:
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2
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.
2
9:
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.
4
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.
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10
:
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5
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_
6
‐1 ‐12
Rogers & Callcott Engineers, Inc.
Ta
b
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3
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An
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E
R
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Limit
(μ g/
m
3 )(μ g/m 3 )
20
ft
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< 38
5 ft
no
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i
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o t De
t
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d
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Fi
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I
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o t De
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e
c
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d
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QC
Sa
m
p
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e
:
Tr
i
p
bl
a
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k
No
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c
t
e
d
< 20
μ g/
m
3 ‐
mi
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o
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a
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BW
I
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I
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BW
I
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m
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ID
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_
6
‐1 ‐12
Rogers & Callcott Engineers, Inc.
Vapor Intrusion Report Former Fuel Systems Facility, Charlotte, North Carolina
June 2012
12\09-123\RPTS\VI Report\Vapor Intrusion Report Rogers & Callcott Engineers, Inc.
APPENDIX A
PHOTOGRAPHS
Indoor Air Sampling Event
Former Fuel Systems Facility, Charlotte, North Carolina
May 3, 2012
Photo No: 1
Date: 5/3/12
View: Indoor air
sample BWIA-2.
Located in
northeast room
(PID = 4.8-5.2
ppm).
Photo No: 2
Date: 5/3/12
View: BWIA-2
with area of oil
staining in
background.
Indoor Air Sampling Event
Former Fuel Systems Facility, Charlotte, North Carolina
May 3, 2012
Photo No: 3
Date: 5/3/12
View: Indoor air
sample BWIA-3
located adjacent
to pit (PID = 2.5-
3.6 ppm).
Photo No: 4
Date: 5/3/12
View: BWIA-3
sample location
with pit in
background.
Indoor Air Sampling Event
Former Fuel Systems Facility, Charlotte, North Carolina
May 3, 2012
Photo No: 5
Date: 5/3/12
View: Partially
filled pit covered
with plastic
sheeting
(looking south).
Photo No: 6
Date: 5/3/12
View: Partially
filled pit covered
with plastic
sheeting
(looking north).
Indoor Air Sampling Event
Former Fuel Systems Facility, Charlotte, North Carolina
May 3, 2012
Photo No: 7
Date: 5/3/12
View: Forklift
remaining in
building during
sample
collection.
Photo No: 8
Date: 5/3/12
View: Truck and
lift remaining in
building during
sample
collection.
Indoor Air Sampling Event
Former Fuel Systems Facility, Charlotte, North Carolina
May 3, 2012
Photo No: 9
Date: 5/3/12
View: Oil stains
and absorbent
on floor in area
of truck and lift.
Photo No: 10
Date: 5/3/12
View:
Motorcycle
remaining in
building during
sampling.
Indoor Air Sampling Event
Former Fuel Systems Facility, Charlotte, North Carolina
May 3, 2012
Photo No: 11
Date: 5/3/12
View: BWIA-4/5
sample location
adjacent to soil
gas sample
location SG-6.
Photo No: 12
Date: 5/3/12
View: BWIA-4/5
with southern
wall of building
in background.
Indoor Air Sampling Event
Former Fuel Systems Facility, Charlotte, North Carolina
May 3, 2012
Photo No: 14
Date: 5/3/12
View:
Southwest
corner of
building just
west of BWIA-
4/5 location.
Photo No: 13
Date: 5/3/12
View: BWIA-4/5
looking west
toward old
furnace and
curing oven.
Indoor Air Sampling Event
Former Fuel Systems Facility, Charlotte, North Carolina
May 3, 2012
Photo No: 16
Date: 5/3/12
View: Paint
thinner and WD-
40 located
along east wall
of building near
entrance to
office space.
Photo No: 15
Date: 5/3/12
View: Propane,
paint can, and
gasoline
containers
stored along
east wall of
building near
entrance to
office space.
Vapor Intrusion Report Former Fuel Systems Facility, Charlotte, North Carolina
June 2012
12\09-123\RPTS\VI Report\Vapor Intrusion Report Rogers & Callcott Engineers, Inc.
APPENDIX B
ANALYTICAL LABORATORY REPORTS AND
CHAIN OF CUSTODY DOCUMENTATION
5/16/2012
Ms. Laura Simpkins
Rogers & Callcott Engineers, Inc.
426 Fairforest Way
Greenville SC 29607
Project Name: BWIA
Project #: 2009-123
Dear Ms. Laura Simpkins
The following report includes the data for the above referenced project for sample(s) received on 5/4/2012 at Air Toxics Ltd.
The data and associated QC analyzed by Modified TO-14A/15 (5&20 ppbv) are
compliant with the project requirements or laboratory criteria with the exception of the deviations noted in the attached case narrative.
Thank you for choosing Air Toxics Ltd. for your air analysis needs. Air Toxics Ltd. is committed to providing accurate data of the highest quality. Please feel free to contact
the Project Manager: Ausha Scott at 916-985-1000 if you have any questions regarding the data in this report.
Regards,
Ausha Scott
Project Manager
Workorder #: 1205098
Page 1 of 14
Ms. Laura Simpkins
Rogers & Callcott Engineers, Inc.
426 Fairforest Way
Greenville, SC 29607
WORK ORDER #:1205098
CLIENT:BILL TO:
PHONE:
Ms. Laura Simpkins
Rogers & Callcott Engineers, Inc.
426 Fairforest Way
Greenville, SC 29607
864-232-1556
05/04/2012
DATE COMPLETED:05/16/2012
P.O. #2009-123
PROJECT #2009-123 BWIA
Work Order Summary
FAX:
DATE RECEIVED:CONTACT:Ausha Scott
NAMEFRACTION #TEST VAC./PRES.
RECEIPT
PRESSURE
FINAL
01A BWIA-1 Modified TO-14A/15 (5&20 p 9.5 "Hg 5 psi
02A BWIA-2 Modified TO-14A/15 (5&20 p 9.5 "Hg 5 psi
03A BWIA-3 Modified TO-14A/15 (5&20 p 9.0 "Hg 5 psi
04A BWIA-4 Modified TO-14A/15 (5&20 p 9.0 "Hg 5 psi
05A BWIA-5 Modified TO-14A/15 (5&20 p 9.0 "Hg 5 psi
06A BWIA-Trip Blank Modified TO-14A/15 (5&20 p 30 "Hg 5 psi
07A Lab Blank Modified TO-14A/15 (5&20 p NA NA
08A CCV Modified TO-14A/15 (5&20 p NA NA
09A LCS Modified TO-14A/15 (5&20 p NA NA
09AA LCSD Modified TO-14A/15 (5&20 p NA NA
CERTIFIED BY:
Laboratory Director
DATE:
Name of Accrediting Agency: NELAP/Florida Department of Health, Scope of Application: Clean Air Act,
Accreditation number: E87680, Effective date: 07/01/11 , Expiration date: 06/30/12.
180 BLUE RAVINE ROAD, SUITE B FOLSOM, CA - 95630
(916) 985-1000 . (800) 985-5955 . FAX (916) 985-1020
05/16/12
Page 2 of 14
This report shall not be reproduced, except in full, without the written approval of Eurofins | Air Toxics, Inc.
Air Toxics Ltd. certifies that the test results contained in this report meet all requirements of the NELAC standards
Certfication numbers: AZ Licensure AZ0719, CA NELAP - 02110CA, LA NELAP - 02089,
NY NELAP - 11291, TX NELAP - T104704434-11-3, UT NELAP -CA009332011-1, WA NELAP - C935
LABORATORY NARRATIVEEPA Method TO-15 Soil GasRogers & Callcott Engineers, Inc.Workorder# 1205098
Six 6 Liter Summa Canister samples were received on May 04, 2012. The laboratory performed analysis
via EPA Method TO-15 using GC/MS in the full scan mode. The method involves concentrating up to 50
mLs of air. The concentrated aliquot is then flash vaporized and swept through a water management
system to remove water vapor. Following dehumidification, the sample passes directly into the GC/MS for
analysis.
This workorder was independently validated prior to submittal using 'USEPA National Functional
Guidelines' as generally applied to the analysis of volatile organic compounds in air. A rules-based, logic
driven, independent validation engine was employed to assess completeness, evaluate pass/fail of relevant
project quality control requirements and verification of all quantified amounts.
There were no receiving discrepancies.
Receiving Notes
There were no analytical discrepancies.
Analytical Notes
Eight qualifiers may have been used on the data analysis sheets and indicates as follows:
B - Compound present in laboratory blank greater than reporting limit (background subtraction not
performed).
J - Estimated value.
E - Exceeds instrument calibration range.
S - Saturated peak.
Q - Exceeds quality control limits.
U - Compound analyzed for but not detected above the reporting limit.
UJ- Non-detected compound associated with low bias in the CCV and/or LCS.
N - The identification is based on presumptive evidence.
File extensions may have been used on the data analysis sheets and indicates
as follows:
a-File was requantified
b-File was quantified by a second column and detector
r1-File was requantified for the purpose of reissue
Definition of Data Qualifying Flags
Page 3 of 14
EPA METHOD TO-15 GC/MS
Summary of Detected Compounds
Client Sample ID: BWIA-1
Lab ID#: 1205098-01A
No Detections Were Found.
Client Sample ID: BWIA-2
Lab ID#: 1205098-02A
No Detections Were Found.
Client Sample ID: BWIA-3
Lab ID#: 1205098-03A
No Detections Were Found.
Client Sample ID: BWIA-4
Lab ID#: 1205098-04A
No Detections Were Found.
Client Sample ID: BWIA-5
Lab ID#: 1205098-05A
No Detections Were Found.
Client Sample ID: BWIA-Trip Blank
Lab ID#: 1205098-06A
No Detections Were Found.
Page 4 of 14
Client Sample ID: BWIA-1
Lab ID#: 1205098-01A
EPA METHOD TO-15 GC/MS
14050529File Name:
Dil. Factor:1.96
Date of Collection: 5/3/12 10:20:00 AM
Date of Analysis: 5/5/12 08:08 PM
(ug/m3)(ug/m3)(ppbv)(ppbv)Compound
AmountRpt. LimitAmountRpt. Limit
9.8 Not Detected 39 Not Detected1,1-Dichloroethene
Container Type: 6 Liter Summa Canister
Limits%RecoverySurrogates
Method
97 70-1301,2-Dichloroethane-d4
97 70-130Toluene-d8
101 70-1304-Bromofluorobenzene
Page 5 of 14
Client Sample ID: BWIA-2
Lab ID#: 1205098-02A
EPA METHOD TO-15 GC/MS
14050530File Name:
Dil. Factor:1.96
Date of Collection: 5/3/12 11:15:00 AM
Date of Analysis: 5/5/12 08:48 PM
(ug/m3)(ug/m3)(ppbv)(ppbv)Compound
AmountRpt. LimitAmountRpt. Limit
9.8 Not Detected 39 Not Detected1,1-Dichloroethene
Container Type: 6 Liter Summa Canister
Limits%RecoverySurrogates
Method
97 70-1301,2-Dichloroethane-d4
96 70-130Toluene-d8
99 70-1304-Bromofluorobenzene
Page 6 of 14
Client Sample ID: BWIA-3
Lab ID#: 1205098-03A
EPA METHOD TO-15 GC/MS
14050532File Name:
Dil. Factor:1.91
Date of Collection: 5/3/12 11:20:00 AM
Date of Analysis: 5/5/12 09:28 PM
(ug/m3)(ug/m3)(ppbv)(ppbv)Compound
AmountRpt. LimitAmountRpt. Limit
9.6 Not Detected 38 Not Detected1,1-Dichloroethene
Container Type: 6 Liter Summa Canister
Limits%RecoverySurrogates
Method
96 70-1301,2-Dichloroethane-d4
98 70-130Toluene-d8
102 70-1304-Bromofluorobenzene
Page 7 of 14
Client Sample ID: BWIA-4
Lab ID#: 1205098-04A
EPA METHOD TO-15 GC/MS
14050531File Name:
Dil. Factor:1.91
Date of Collection: 5/3/12 11:25:00 AM
Date of Analysis: 5/5/12 09:07 PM
(ug/m3)(ug/m3)(ppbv)(ppbv)Compound
AmountRpt. LimitAmountRpt. Limit
9.6 Not Detected 38 Not Detected1,1-Dichloroethene
Container Type: 6 Liter Summa Canister
Limits%RecoverySurrogates
Method
96 70-1301,2-Dichloroethane-d4
97 70-130Toluene-d8
100 70-1304-Bromofluorobenzene
Page 8 of 14
Client Sample ID: BWIA-5
Lab ID#: 1205098-05A
EPA METHOD TO-15 GC/MS
14050533File Name:
Dil. Factor:1.91
Date of Collection: 5/3/12 11:25:00 AM
Date of Analysis: 5/5/12 09:49 PM
(ug/m3)(ug/m3)(ppbv)(ppbv)Compound
AmountRpt. LimitAmountRpt. Limit
9.6 Not Detected 38 Not Detected1,1-Dichloroethene
Container Type: 6 Liter Summa Canister
Limits%RecoverySurrogates
Method
98 70-1301,2-Dichloroethane-d4
97 70-130Toluene-d8
100 70-1304-Bromofluorobenzene
Page 9 of 14
Client Sample ID: BWIA-Trip Blank
Lab ID#: 1205098-06A
EPA METHOD TO-15 GC/MS
14050534File Name:
Dil. Factor:1.00
Date of Collection: 5/3/12 11:30:00 AM
Date of Analysis: 5/5/12 10:07 PM
(ug/m3)(ug/m3)(ppbv)(ppbv)Compound
AmountRpt. LimitAmountRpt. Limit
5.0 Not Detected 20 Not Detected1,1-Dichloroethene
Container Type: 6 Liter Summa Canister
Limits%RecoverySurrogates
Method
98 70-1301,2-Dichloroethane-d4
98 70-130Toluene-d8
101 70-1304-Bromofluorobenzene
Page 10 of 14
Client Sample ID: Lab Blank
Lab ID#: 1205098-07A
EPA METHOD TO-15 GC/MS
14050522File Name:
Dil. Factor:1.00
Date of Collection: NA
Date of Analysis: 5/5/12 04:56 PM
(ug/m3)(ug/m3)(ppbv)(ppbv)Compound
AmountRpt. LimitAmountRpt. Limit
5.0 Not Detected 20 Not Detected1,1-Dichloroethene
Container Type: NA - Not Applicable
Limits%RecoverySurrogates
Method
97 70-1301,2-Dichloroethane-d4
98 70-130Toluene-d8
100 70-1304-Bromofluorobenzene
Page 11 of 14
Client Sample ID: CCV
Lab ID#: 1205098-08A
EPA METHOD TO-15 GC/MS
14050502File Name:
Dil. Factor:1.00
Date of Collection: NA
Date of Analysis: 5/5/12 08:00 AM
%RecoveryCompound
1041,1-Dichloroethene
Container Type: NA - Not Applicable
Limits%RecoverySurrogates
Method
96 70-1301,2-Dichloroethane-d4
100 70-130Toluene-d8
107 70-1304-Bromofluorobenzene
Page 12 of 14
Client Sample ID: LCS
Lab ID#: 1205098-09A
EPA METHOD TO-15 GC/MS
14050503File Name:
Dil. Factor:1.00
Date of Collection: NA
Date of Analysis: 5/5/12 08:24 AM
%RecoveryCompound
1221,1-Dichloroethene
Container Type: NA - Not Applicable
Limits%RecoverySurrogates
Method
96 70-1301,2-Dichloroethane-d4
99 70-130Toluene-d8
108 70-1304-Bromofluorobenzene
Page 13 of 14
Client Sample ID: LCSD
Lab ID#: 1205098-09AA
EPA METHOD TO-15 GC/MS
14050504File Name:
Dil. Factor:1.00
Date of Collection: NA
Date of Analysis: 5/5/12 08:45 AM
%RecoveryCompound
1181,1-Dichloroethene
Container Type: NA - Not Applicable
Limits%RecoverySurrogates
Method
94 70-1301,2-Dichloroethane-d4
99 70-130Toluene-d8
105 70-1304-Bromofluorobenzene
Page 14 of 14
Vapor Intrusion Report Former Fuel Systems Facility, Charlotte, North Carolina
June 2012
12\09-123\RPTS\VI Report\Vapor Intrusion Report Rogers & Callcott Engineers, Inc.
APPENDIX C
WORST CASE INDOOR AIR CONCENTRATION
CALCULATIONS
Vapor Intrusion Calculation (5019 Hovis Rd., Charlotte, NC)
‐ Vapor intrusion occurs due to pressure differential between ground surface and building interior (McHugh, 2006)
Assumptions:
‐ Pressure gradient between ground surface and building interior only due to temperature difference
‐ HVAC not currently running in facility
‐ Volumetric flow rate (Q) is proportional to temperature by the following relationship:
Q € sqrt((Ti ‐ Ts)/Ti)(ASHRAE Fundamentals Handbook, 1997)
Q = flow rate
Ti = indoor temperature (K)
Ts = subsurface temperature (K)
Thus: Qw/Q =sqrt((Tiw‐Tis)*Ti)/(Ti‐Ts)*Tiw))
Qw = Worst‐case flow rate
Tw = Worst‐case subsurface temperature
Tiw = Worst‐case indoor temperature ‐ Assumed to be 60F based on 1/19/12 Site visit
Ti (from Site measurements during sampling): Ti (F)=74.5 ‐ Measured indoor temp in Fahrenheit
Ti (K)= 296.61
Ts (from NRCS website, Critz, VA, 5/3/2012): Ts(700)=20.2 ‐ Readings in Celcius
Ts(800)=20.3 ‐ (700) corresponds to 7:00AM
Ts(900)=21.4
Ts(1000)= 23.3
Ts(1100)= 25.3
\12\09‐123\RPTS\VI Report\Appendix_C_Worst Case Calculations Rogers & Callcott Engineers, Inc.Page 1 of 1
Ts(K)= 295.10 ‐Average temperature over sampling period
Tw (from NRCS website, Critz, VA, 1/19/2012) Tsw(700)= 2.9 ‐ Readings in Celcius
Tsw(800)= 2.7
Tsw(900)= 2.6
Tsw(1000)= 2.5
Tsw(1100)= 2.6
Tsw(K)= 275.66 ‐Average temperature over theoretical sampling period
Tiw(K)= 288.56 ‐Assume 60F
Qw/Q =2.96
and:
Qw =2.96 *Q
Maximum Concentration (RL)=Cmax < 38 ug/m3 ‐ Assumed 1,1‐DCE concentration at the reporting limit
Cmaxw < 113 ug/m3 ‐ Maximum concentration under worst‐case conditions
\12\09‐123\RPTS\VI Report\Appendix_C_Worst Case Calculations Rogers & Callcott Engineers, Inc.Page 1 of 1
Vapor Intrusion Report
Former Fuel Systems Facility, Charlotte, North Carolina
June 2012
12\09‐123\RPTS\VI Report\Appendix C_Derivation Page 1 of 2 Rogers & Callcott Engineers, Inc.
Derivation of the advective flow rate ratio (Qw/Q):
The advective flow rate due to the temperature difference between two adjoining volumes can
be calculated based on the following equation [American Society of Heating, Refrigeration, and
Air‐Conditioning Engineers (ASHRAE), 1997]:
ܳൌܥܣ ඨ2݄݃ ܶ െܶ௦
ܶ
Where:
Q = the advective flow rate (m3/s)
C = discharge coefficient (typically 0.65 – 0.70)
A = flow area between two volumes (m2)
g = gravitational acceleration (9.81 m/s2)
h = building height (ft)
Ti = average indoor air temperature (K)
Ts = average air temperature of subslab soil (K)
Because the gravity, building height, flow area (i.e. – area of cracks in the slab through which
vapor flow occurs), and the discharge coefficients are constant throughout the year, the above
equation can be re‐arranged to the following form:
ܳඨ ܶ
ܶ െ ܶ௦
ൌConstant
Thus, the following relationship between the flow rate (Q) during the indoor air sampling and
the flow rate during worst case conditions (Qw) can be derived:
ܳඨ ܶ
ܶ െ ܶ௦
ൌܳ௪ඨ ܶ௪
ܶ௪ െ ܶ௦௪
Where:
Qw = the advective flow rate during worst case conditions (m3/s)
Tiw = average indoor air temperature during worst case conditions (K)
Tsw = average air temperature of subslab soil during worst case conditions (K)
Vapor Intrusion Report
Former Fuel Systems Facility, Charlotte, North Carolina
June 2012
12\09‐123\RPTS\VI Report\Appendix C_Derivation Page 2 of 2 Rogers & Callcott Engineers, Inc.
The equation can be re‐arranged to determine the ratio between the advective flow rate into
the building from the subsurface under worst case conditions and during the May sampling
event as follows:
ܳ௪
ܳ ൌ ඨሺܶ௪ െܶ௦௪ሻܶ
ሺܶ െܶ௦ሻܶ௪