HomeMy WebLinkAboutDC920075_20220204_FINAL_7_Bloodworth_VI_Assessment_nonDSCAREPORT DATE:February 3, 2022
MAA PROJECT #:021R3943.02
VAPOR INTRUSION ASSESSMENT
7 NORTH BLOODWORTH STREET
Raleigh, Wake County, North Carolina
ENGINEERING & ENVIRONMENTAL SOLUTIONS
PREPARED FOR:PREPARED BY:
Andrea Bosquez-Porter
727 W. Hargett Street
Raleigh, NC, 27603
Mid Atlantic Associates, Inc.
409 Rogers View Court
Raleigh, NC, 27610
TABLE OF CONTENTS
1.0 GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Laboratory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2.0 SUMMARY OF FIELD ACTIVITIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2.1 Indoor Air Sample Collection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2.2 Soil Gas Sample Collection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.2.1 Vapor Pin Installation Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.2.2 Helium Leak Check Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.2.3 Sample Collection Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.0 SUMMARY OF LABORATORY ANALYTICAL RESULTS . . . . . . . . . . . . . . . . . 4
3.1 Indoor Air Sampling Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.2 Soil Gas Sampling Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.3 Risk Calculations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4.0 QUALITY ASSURANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
5.0 FINDINGS AND CONCLUSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
DRAWINGS
Drawing 1 - Topographic Map
Drawing 2 - Sample Location Map
TABLES
Table 1 - Sampling Summary
Table 2 - Constituents Detected in Indoor Air & Soil Gas
TABLE OF APPENDICES
APPENDIX A - Indoor Air Building Survey and Sampling Form
APPENDIX B - Laboratory Analytical Report of Soil Gas and Indoor Air Samples
APPENDIX C - Risk Calculations for Soil Gas and Indoor Air
1.0 GENERAL INFORMATION
1.1 Introduction
The following table provides a brief summary of the Subject Property.
Property
Size 0.08 acres
Former/
Current
Uses
Land use at the Subject Property has been confirmed by historical
sources back to 1909, when the Subject Property appears to have
been developed with one residential structure which reflects
present-day configuration.City directories confirm residential use of
the Subject Property between 1922 and 1968. City directories
indicate the Subject Property has been utilized for commercial office
purposes from approximately 1970 through present day.
Potential
Vapor
Intrusion
(VI) Sources
Historical dry-cleaning operations on the south adjacent property
from approximately 1971 through 2012.Previous assessment
activities identified perchloroethylene (PCE) and trichloroethylene
(TCE) in groundwater along the southern site boundary at
concentrations exceeding the applicable vapor intrusion screening
levels (VISLs) for groundwater to indoor air. No other constituents
were reported in the groundwater at concentrations exceeding the
VISLs.
Presence of
Elevators &
Stairwells
The Subject Property does not contain an elevator. The flights of
stairs at the Subject Property are considered open-air, and are not
considered stairwells.
Assessment
Areas The sub-grade basement is unoccupied.
Pertinent
Map
Attachments
A topographic site map is included as Drawing 1. A current site map
with sample locations is included as Drawing 2.
1.2 Laboratory
Enthalpy Analytical Laboratory (Enthalpy)
800 Capitola Drive, Suite 1
Durham, North Carolina 27713
(919) 850-4392
LELAP Lab ID: 04010
Contact: Mr. David Myers
2.0 SUMMARY OF FIELD ACTIVITIES
Mid-Atlantic collected one indoor air sample and two sub-slab soil gas samples. See
Table 1 for a summary of sample locations and assessment details. Sampling was
performed in general accordance with the Inactive Hazardous Sites Program Guidelines
for Assessment and Cleanup of Contaminated Sites (January 2020) and the North
Carolina Department of Environmental Quality, Division of Waste Management, Vapor
Intrusion Guidance (March 2018).
On January 25, 2022, Mid-Atlantic conducted a site reconnaissance to identify potential
sources of indoor air contaminants inside the Subject Property.The results of the survey
are included in the Indoor Air Building Survey and Sampling Form (Appendix A).
Typically this survey is completed 24 hours prior to indoor air sampling; however,
Mid-Atlantic completed the survey on the same day of indoor air sampling due to time
constraints. During the performance of the survey, latex paints were found inside the
space in small quantities (<5 gallons) and not removed. The owner of the property, DFS
Investments, LLC, did not indicate recent painting or other activities that may impact
indoor air quality in the last 12 months.
2.1 Indoor Air Sample Collection
On January 25, 2022, Mid-Atlantic mobilized to the site to collect one indoor air sample
from the basement at the Subject Property (IA-1).The sample was collected using a
laboratory supplied 6-liter, individually certified, stainless-steel Summa canister and a
flow regulator designed to restrict the maximum flow rate to 8-10 mL/min. The intake for
the canister was set approximately between 3.5 feet above the floor. The canister used
during indoor air sampling activities was confirmed to have retained greater than 90%
of its initial volume (>27” Hg) prior to sampling. The canister was left open over an
approximately 8-hour period and closed once 8 hours had passed or a vacuum of 10 to
5 inches of mercury (10" to 5"Hg) was achieved. In the 24 hours prior to sampling, the
space was used under normal operating conditions. The approximate sample location
is shown on Drawing 2. The canister was placed on hold in the laboratory and, following
receipt of the subsequent sub-slab soil gas sampling results, taken off hold and analyzed
for trichloroethylene (TCE) and tetrachloroethylene (PCE) according to EPA Method
TO-15.
Vapor Intrusion Assessment
7 North Bloodworth Street
Raleigh, North Carolina
February 3, 2022
Page 2
2.2 Soil Gas Sample Collection
Following the collection of the indoor air sample, Mid-Atlantic collected two sub-slab
soil gas samples (SS-1 and SS-2)from beneath the basement floor at the Subject
Property.The sample locations were selected to be greater than five feet away from
exterior walls, cracks, or seams in the concrete basement floor.The approximate
sample locations are shown on Drawing 1.
2.2.1 Vapor Pin Installation Procedures
Sub-slab borings were advanced at two locations at the Subject Property to support
the installation of vapor pins and collection of sub-slab soil gas samples.To create the
sub-slab sampling ports, a rotary-impact drill equipped with a decontaminated spline drill
bit was utilized to drill a 5/8-inch diameter hole through the concrete slab. The concrete
slab thickness varied from approximately eight to ten inches.Beneath the slab at both
sample locations appeared to be red clay. Upon completion of each boring, a vapor
sampling probe was established using a new “Vapor Pin™” which utilizes a brass barb
fitting with a silicone sleeve to create a seal with the concrete when inserted using
an installation/extraction tool. The vapor pin was then fitted with ¼-inch outer diameter
Teflon-lined tubing to complete the vapor sampling probe assembly. Subsequent helium
leak check and soil gas sampling activities are discussed below in Sections 2.2.2 and
2.2.3, respectively.
2.2.2 Helium Leak Check Procedures
A leak check was performed at each probe location using a plastic shroud, helium
gas, and a portable helium gas detector after the vapor probe location was allowed to
equilibrate for at least 20 minutes. A plastic shroud was placed over the sub-slab vapor
probe location and sampling train. A 3-way valve was placed on the probe termination
and connected to the sampling apparatus. Helium was introduced into the shroud via
tubing from the cylinder, and a grab sample was collected by filling a Tedlar bag using the
exhaust port of the purge syringe while purging the sample location of a minimum of three
system volumes of air at a rate of approximately 200 mL/min. One system volume was
approximately 60 mL, and each location was purged of approximately 600 mL. Helium
concentrations of 50,000 to 200,000 parts per million were maintained within the shroud
during purging. The results of Mid-Atlantic’s helium leak checks at each sample location
are as follows:
Sample
ID
Helium Concentration Under
Shroud
Helium Concentration in Tedlar
Bag
SS-1 76,000 PPM 25 PPM
SS-2 112,000 PPM 0.0 PPM
Vapor Intrusion Assessment
7 North Bloodworth Street
Raleigh, North Carolina
February 3, 2022
Page 3
Because the helium concentrations detected in the Tedlar bag were less than 10% of
the concentration under the shroud during leak testing, the seals around the vapor probe
were considered acceptable.
2.2.3 Sample Collection Procedures
After performing the helium leak check at the interior sub-slab soil gas sample locations,
sub-slab soil gas samples were collected using laboratory supplied, batch-certified,
1-liter, stainless steel canisters at a maximum flow rate of 200 mL/min. The canisters
used during sub-slab sampling activities were confirmed to have retained greater than
90% of their initial volume (>27” Hg) prior to sampling. The canisters were left open over
an approximately 5-minute period and closed once a vacuum of 5” Hg was achieved.
Following sampling activities, the soil gas and indoor air samples were collected by a
courier and sent to to Enthalpy Analytical Laboratory Laboratory (Enthalpy) in Durham,
North Carolina under proper chain of custody for analysis. The canisters were analyzed
in the laboratory for TCE and PCE according to EPA Method TO-15. Once sub-slab
activities were completed, the vapor probes were removed from the slab and filled with
hydraulic cement.
3.0 SUMMARY OF LABORATORY ANALYTICAL RESULTS
3.1 Indoor Air Sampling Results
The laboratory analytical report and chain-of-custody record for the indoor air
sample collected on January 25, 2022 are provided in Appendix B and summarized in
Table 2. The results of the indoor air sampling activities were compared to the NCDEQ
June 2021 Residential and Non-Residential Indoor Air Screening Levels (IASLs).As
summarized, TCE was not detected in the indoor air sample above laboratory method
detection limits. The indoor air sample exhibited PCE below Residential and
Non-Residential IASLs.
3.2 Soil Gas Sampling Results
The laboratory analytical report and chain-of-custody record for soil gas samples
collected on January 25, 2022 are provided in Appendix B and summarized in Table
2. The results of the soil gas sampling activities were compared to the June 2021
Residential and Non-Residential Soil Gas Screening Levels (SGSLs). As summarized,
PCE was detected in both sub-slab soil gas samples at concentrations which exceeded
the Residential and Non-Residential SGSL.Soil gas sample SS-1 exhibited TCE at
a concentration which exceeded the Residential SGSL, but did not exceed the
Non-Residential SGSLs.Concentrations of TCE detected in SS-2 exceeded both
Residential and Non-Residential SGSLs.Concentrations of PCE detected in SS-1 and
SS-2 also exceeded both the Residential and Non-Residential SGSLs.
Vapor Intrusion Assessment
7 North Bloodworth Street
Raleigh, North Carolina
February 3, 2022
Page 4
3.3 Risk Calculations
The Division of Waste Management (DWM) establishes vapor intrusion SGSLs and
indoor air IASLs for individual compounds for both Residential and Non-Residential
(industrial/commercial) exposure scenarios. The DWM allows a maximum cumulative
cancer risk for all carcinogens of 1.0E-4 and a maximum cumulative hazard index of 1 for
all non-carcinogens in soil gas and indoor air. Mid-Atlantic compared the sub-slab and
indoor air sampling results to the DWM Residential and Non-Residential SGSLs/IASLs
then calculated the cancer risk and non-cancer risk hazard quotient for compounds
detected above the MDL.
Residential and Non-Residential cumulative cancer risk and cumulative non-cancer
hazard indexes were then determined for the sub-slab soil gas using the highest detected
concentration for each compound in the samples (Appendix C). The cumulative
Residential and Non-Residential exposure cancer risk sums and non-cancer hazard
indexes for the sub-slab soil gas samples are summarized in the following table:
Sub-Slab Soil Gas Risk Calculations
Exposure
Unit
Non-Residential
Calculated
Carcinogenic
Risk Sum
Non-Residential
Cumulative
Non-Carcinogenic
Hazard Index
Residential
Calculated
Carcinogenic
Risk Sum
Residential
Cumulative
Non-Carcinogenic
Hazard Index
SS-1
& SS-2 1.1E-5 3.1 1.5E-4 3.9E1
As indicated, the soil gas exposure scenarios exceeded the Residential target cumulative
cancer risk, Residential and Non-Residential cumulative non-cancer hazard
indexes.Therefore, the indoor air sample was taken off hold and analyzed in the
laboratory, with the subsequent cumulative risk calculations discussed below.
Residential and Non-Residential cumulative cancer risk and cumulative non-cancer
hazard indexes were determined for the indoor air sample using the detected
concentration for PCE in sample IA-1. Trichloroethylene was not detected in sample
IA-1 above method detection limits, and was not included in the risk calculations since
the detection limits were below the IASLs for TCE.. Copies of the Residential and
Non-Residential risk calculations are included in Appendix C. The Residential and
Non-Residential exposure cancer risk sums and non-cancer hazard indexes for the
indoor air sample is summarized in the following table:
Vapor Intrusion Assessment
7 North Bloodworth Street
Raleigh, North Carolina
February 3, 2022
Page 5
Indoor Air Risk Calculations
Exposure
Unit
Non-Residential
Calculated
Carcinogenic
Risk Sum
Non-Residential
Cumulative
Non-Carcinogenic
Hazard Index
Residential
Calculated
Carcinogenic
Risk Sum
Residential
Cumulative
Non-Carcinogenic
Hazard Index
IA-1 4.6E-8 1.2E-2 2.0E-7 5.2E-2
As indicated, neither the target cumulative cancer risk of 1.0E-4 nor the target cumulative
non-cancer hazard index of 1 were exceeded for the indoor air sample for either
corresponding risk scenario.
4.0 QUALITY ASSURANCE
Mid-Atlantic filled each laboratory provided Summa canister such that the final vacuum in
the canister was greater than 4 inches of mercury. The chain-of-custody was completed
and packed with the samples. The Mid-Atlantic field technician returned to the office with
the packed boxes which were picked up by an Enthalpy courier. The courier then hand
delivered the boxes to the laboratory located in Durham, North Carolina. The laboratory
report in Appendix B reports level II QA/QC.
5.0 FINDINGS AND CONCLUSIONS
The overall objective of this assessment was to determine if the off-site release of
dry-cleaning solvent from the south adjacent property has resulted in a vapor intrusion
scenario at the Subject Property. Mid-Atlantic offers the following conclusions based on
the results of this assessment as they pertain to the Subject Property:
• TCE and PCE were detected in sub-slab soil gas samples at concentrations
above their respective DWM Residential and Non-Residential SGSLs;
• TCE was not detected in the indoor air sample above laboratory method detection
and/or SGSLs;
• PCE was detected in the indoor air sample at concentrations above laboratory
method detection limits but below IASLs; and
• The cancer risk and cumulative non-cancer hazard indexes for the indoor air
sample did not exceed the target cancer risk sum of 1.0E-4 nor the target
cumulative non-cancer hazard index of 1 for each risk scenario.
Based on the data collected during this investigation, vapor intrusion does not appear to
be causing an unacceptable risk for the Subject Property. Based on the results of the vapor intrusion assessment, no further investigation is warranted at this time.
Vapor Intrusion Assessment
7 North Bloodworth Street
Raleigh, North Carolina
February 3, 2022
Page 6
DRAWINGS
´
TOPOGRAPHIC SITE MAP7 NORTH BLOODWORTH STREETRALEIGH, NORTH CAROLINA
DRAWN BY:DATE:
ENG. CHECK:
JOB NO:
APPROVAL:
DRAFTCHECK:GIS NO:
DWG NO:
REFERENCES:
SCALE:
NOVEMBER 2021
000R3943.00
2G-R3943.00-11
1. RALEIGH WEST, NC DIGITAL RASTER GRAPHICS, USGS. SCANNED FROM 1:24,000-SCALE WAKE, NC TOPOGRAPHIC MAPS, PUBLISHED 2019, USGS.2. INSET MAP DIGITAL DATA FROM 2002 NATIONAL TRANSPORTATION ATLAS, BUREAU OF TRANSPORTATION STATISTICS, WASHINGTON, D.C. WAKE COUNTY GIS.
CONTOUR INTERVAL = 10 FEET
0 500 1,000Feet
SITE
1:6,000
GCH
§¨¦U70
§¨¦I440
§¨¦I40
§¨¦U64
WAKE
AREA SHOWNWITHIN WAKE COUNTY
N B
L
O
O
D
W
O
R
T
H
S
T
E EDENTON ST
NEW BERN AVE
´
SAMPLE LOCATION MAP7 NORTH BLOODWORTH STREETRALEIGH, NORTH CAROLINA
DRAWN BY:DATE:
ENG. CHECK:
JOB NO:
APPROVAL:
DRAFTCHECK:GIS NO:
DWG NO:
REFERENCES:
SCALE:
FEBRUARY 2022
000R3943.01
2G-R3943.01-22
1. MID-ATLANTIC FIELD NOTES.2. NCONE MAP LATEST ORTHOIMGERY3. SHAPEFILES PROVIDED BY WAKE COUNTY GIS
0 50 100Feet1 inch equals 50 feet
GCH
Legend
#*Sub-Slab and Indoor Air Sample Location
!(Sub-Slab Soil Gas Sample Location
Subject Property
Parcel Boundaries
!(SS-1
#*SS-2 & IA-1
TABLES
SAMPLE ID SAMPLE DATE SAMPLE TYPE SAMPLE DEPTH
IA-1 1/25/2022 Indoor Air 3-4 feet above floor,
southern basement interior
SS-1 1/25/2022 Soil Gas Directly below slab, northern
basement interior
SS-2 1/25/2022 Soil Gas Directly below slab, southern
basement interior
MID-ATLANTIC JOB NO. 021R3943.02
TABLE 1
SAMPLING SUMMARY
7 NORTH BLOODWORTH STREET
RALEIGH, NORTH CAROLINA
< 0.232 -- -- 0.42 1.8
2.18 -- -- 8.3 35
-- 17.4 701 14 180
--6,004 39,804 280 3,500
Notes:
Concentration units; ug/m3 = micrograms per cubic meter
NCDEQ = North Carolina Department of Environmental Quality
DWM = Division of Waste Management
ND = Not Detected
-- = Not Applicable
Underlined values indicate concentrations exceed Non-Residential Screening Levels
Bold values indicate concentrations exceed Residential Screening Levels
Tetrachloroethene (PCE)
Indoor Air Screening Levels
Soil Gas Screening LevelsSoil Gas
Indoor Air
Tetrachloroethene (PCE)
Trichloroethene (TCE)
Trichloroethene (TCE)
7 NORTH BLOODWORTH STREET
CONSTITUENTS DETECTED IN INDOOR AIR & SOIL GAS
TABLE 2
NCDEQ DWM
Residential Vapor
Intrusion Screening
Levels (June 2021)
NCDEQ DWM Non-
Residential Vapor
Intrusion Screening
Levels (June 2021)
Analyte
MID-ATLANTIC JOB NO.: 021R3943.02
RALEIGH, NORTH CAROLINA
IA-1 SS-1 SS-2
APPENDIX A - INDOOR AIR BUILDING SURVEY AND SAMPLING
FORM
APPENDIX B - LABORATORY ANALYTICAL REPORT OF SOIL GAS
AND INDOOR AIR SAMPLES
Mid-Atlantic
Associates, Inc.
409 Rogers View Ct
Raleigh, NC 27610
7 N Bloodworth VI Assessment
Raleigh, NC
Client Project # R3943.02
Analytical Report
(0122-116R)
EPA Method TO-15
Client Specified TO-15 Target Compound List
Enthalpy Analytical, LLC
Phone: (919) 850 - 4392 / Fax: (919) 850 - 9012 / www.enthalpy.com
800-1 Capitola Drive Durham, NC 27713-4385
Results
EA# 0122-116R Page 3 of 24
Quantitation Report Enthalpy Analytical, LLC
Sample Name : SS-1
Sample Info : 0122-116; 500L load; Can #11292
Data File : T2200279.D
Dilution : 1
Pressurization Factor : 2.407
Acquisition Date : 2022-01-26 15:37:55
Instrument Method : TO15-SCN2.M
Matrix : AIR
Target Compound
oncen ra on
(PPBV)(PPBV)(PPBV)
oncen ra on
(ug/m3)(ug/m3)(ug/m3)Flag *
Trichloroethene 3.23 0.0973 0.0842 17.4 0.523 0.453
Internal Standards Response
e en on me
(min)
oncen ra on
(PPBV) Flag *
1,4-Difluorobenzene (IS) 1,749,702 14.20 5.16 PASS
Chlorobenzene-d5 (IS) 1,239,715 18.46 4.93 PASS
(ND) = Not Detected* (J) = Below Calibration Range, (E) = Above Calibration Range, (m) = Manual Integration IS Acce tance Criteria: RT +- 20 sec Res onse +- 40%
0122-116 TO15_Quant_Ambient - v2
EA# 0122-116R Page 4 of 24
Quantitation Report Enthalpy Analytical, LLC
Sample Name : SS-1
Sample Info : 0122-116; *20=25 load; Can #11292
Data File : T2200280.D
Dilution : 20
Pressurization Factor : 2.407
Acquisition Date : 2022-01-26 16:19:34
Instrument Method : TO15-SCN2.M
Matrix : AIR
Target Compound
oncen ra on
(PPBV)(PPBV)(PPBV)
oncen ra on
(ug/m3)(ug/m3)(ug/m3)Flag *
Tetrachloroethene 885 1.97 1.68 6,004 13.4 11.4
Internal Standards Response
e en on me
(min)
oncen ra on
(PPBV) Flag *
1,4-Difluorobenzene (IS) 1,817,568 14.20 5.16 PASS
Chlorobenzene-d5 (IS) 1,457,480 18.46 4.93 PASS
(ND) = Not Detected* (J) = Below Calibration Range, (E) = Above Calibration Range, (m) = Manual Integration IS Acce tance Criteria: RT +- 20 sec Res onse +- 40%
0122-116 TO15_Quant_Ambient - v2
EA# 0122-116R Page 5 of 24
Quantitation Report Enthalpy Analytical, LLC
Sample Name : SS-2
Sample Info : 0122-116; *10=50mL load; Can #11264
Data File : T2200286.D
Dilution : 10
Pressurization Factor : 2.376
Acquisition Date : 2022-01-26 20:45:28
Instrument Method : TO15-SCN2.M
Matrix : AIR
Target Compound
oncen ra on
(PPBV)(PPBV)(PPBV)
oncen ra on
(ug/m3)(ug/m3)(ug/m3)Flag *
Trichloroethene 130 0.961 0.832 701 5.16 4.47
Internal Standards Response
e en on me
(min)
oncen ra on
(PPBV) Flag *
1,4-Difluorobenzene (IS) 1,638,370 14.20 5.16 PASS
Chlorobenzene-d5 (IS) 1,260,124 18.46 4.93 PASS
(ND) = Not Detected* (J) = Below Calibration Range, (E) = Above Calibration Range, (m) = Manual Integration IS Acce tance Criteria: RT +- 20 sec Res onse +- 40%
0122-116 TO15_Quant_Ambient - v2
EA# 0122-116R Page 6 of 24
Quantitation Report Enthalpy Analytical, LLC
Sample Name : SS-2
Sample Info : 0122-116; *50=10mL load (2nd TP); Can #11264
Data File : T2200288.D
Dilution : 50
Pressurization Factor : 3.922
Acquisition Date : 2022-01-26 22:08:10
Instrument Method : TO15-SCN2.M
Matrix : AIR
Target Compound
oncen ra on
(PPBV)(PPBV)(PPBV)
oncen ra on
(ug/m3)(ug/m3)(ug/m3)Flag *
Tetrachloroethene 5,869 8.02 6.86 39,804 54.4 46.6
Internal Standards Response
e en on me
(min)
oncen ra on
(PPBV) Flag *
1,4-Difluorobenzene (IS) 1,595,956 14.20 5.16 PASS
Chlorobenzene-d5 (IS) 1,283,897 18.46 4.93 PASS
(ND) = Not Detected* (J) = Below Calibration Range, (E) = Above Calibration Range, (m) = Manual Integration IS Acce tance Criteria: RT +- 20 sec Res onse +- 40%
0122-116 TO15_Quant_Ambient - v2
EA# 0122-116R Page 7 of 24
Quantitation Report Enthalpy Analytical, LLC
Sample Name : IA-1
Sample Info : 0122-116; *0.667=750mL load; Can #1443
Data File : T2200277.D
Dilution : 0.667
Pressurization Factor : 1.850
Acquisition Date : 2022-01-26 14:02:10
Instrument Method : TO15-SCN2.M
Matrix : AIR
Target Compound
oncen ra on
(PPBV)(PPBV)(PPBV)
oncen ra on
(ug/m3)(ug/m3)(ug/m3)Flag *
Trichloroethene ND 0.0499 0.0432 ND 0.268 0.232
Tetrachloroethene 0.321 0.0505 0.0432 2.18 0.342 0.293
Internal Standards Response
e en on me
(min)
oncen ra on
(PPBV) Flag *
1,4-Difluorobenzene (IS) 1,723,801 14.19 5.16 PASS
Chlorobenzene-d5 (IS) 1,215,795 18.46 4.93 PASS
(ND) = Not Detected
* (J) = Below Calibration Range, (E) = Above Calibration Range, (m) = Manual Integration
IS Acce tance Criteria: RT +- 20 sec Res onse +- 40%
0122-116 TO15_Quant_Ambient - v2
EA# 0122-116R Page 8 of 24
Enthalpy Analytical -- Canister Pressurization
Job No.
Company
Site
Can Number 11264 11292 1443
Job 0122-116 0122-116 0122-116
Sample ID SS-2 SS-1 IA-1
CleanDate 06/19/2021 12/21/2021 12/13/2021
LeakCheckDate 06/21/2021 12/20/2021 12/16/2021
LeakCheckAnalyst aamears aamears aamears
BlankCheckRef T2102790 T2104852 Y2103925
Weather Station ID 71 71 71
Weather Station Exp. 03/04/2022 03/04/2022 03/04/2022
Transducer ID 3 3 3
Transducer Exp.02/19/2022 02/19/2022 02/19/2022
Can Size (L)1.4 1.4 6
Evac Temp (F)69.2 69.2 69.2
Evac Pbar (mmHg)765.6 765.6 765.6
Evac Gauge (mmHg) -765.6 -765.6 -765.6
Evac Analyst aamears aamears aamears
Evac Time 01/26/22 12:17 01/26/22 12:18 01/26/22 12:19
Evac Vol (L)0.000 0.000 0.000
Recd. Temp (F)69.9 69.9 69.9
Recd. Pbar (mmHg)762.8 762.8 762.8
Recd. Gauge (mmHg) -100.0 -109.0 -224.0
Recd Vol (L)1.216 1.200 4.238
P1 Temp (F)69.9 69.9 69.9
P1 Pbar (mmHg)762.8 762.8 762.8
P1 Gauge (mmHg)812.0 811.0 234.0
P1 Analyst aamears aamears aamears
P1 Time 01/26/22 13:32 01/26/22 13:31 01/26/22 13:24
P1 Vol (L)2.890 2.889 7.841
P1 DF Override false false false
P1 Dilution Factor 2.376 2.407 1.850
Mid 1-2 Temp (F)68.5
Mid 1-2 Pbar (mmHg) 764.8
Mid 1-2 Gauge (mmHg) 245.0
Mid 1-2 Vol (L)1.858
P2 Temp (F)68.5
P2 Pbar (mmHg)764.8
P2 Gauge (mmHg)902.0
P2 Analyst ddaniels
P2 Time 01/27/22 09:15
P2 Vol (L)3.068
P2 Dilution Factor 3.922
0122-116
MidAtlantic Associates Inc
7 N Bloodworth WI Assessment-Raleigh, NC
Canister Pressurization Report 20210215 Report Printed 1/27/2022 9:16:48 AM
EA# 0122-116R Page 9 of 24
Lab QC
EA# 0122-116R Page 10 of 24
Quantitation Report Enthalpy Analytical, LLC
Sample Name : SS-1 LD
Sample Info : 0122-116; *20=25 load; Can #11292
Data File : T2200281.D
Dilution : 20
Pressurization Factor : 2.407
Acquisition Date : 2022-01-26 17:01:13
Instrument Method : TO15-SCN2.M
Matrix : AIR
Target Compound
oncen ra on
(PPBV)(PPBV)(PPBV)
oncen ra on
(ug/m3)(ug/m3)(ug/m3) % Diff Flag *
Tetrachloroethene 929 1.97 1.68 6,299 13.4 11.4 4.8
Internal Standards Response
e en on me
(min)
oncen ra on
(PPBV) Flag *
1,4-Difluorobenzene (IS) 1,698,035 14.20 5.16 PASS
Chlorobenzene-d5 (IS) 1,372,723 18.46 4.93 PASS
(ND) = Not Detected
* (J) = Below Calibration Range, (E) = Above Calibration Range, (m) = Manual Integration
IS Acce tance Criteria: RT +- 20 sec Res onse +- 40%
0122-116 TO15_Quant_Ambient - v2
EA# 0122-116R Page 11 of 24
Quantitation Report Enthalpy Analytical, LLC
Sample Name : Humid Blank #10893
Sample Info : 500mL load; Can #10893
Data File : T2200275.D
Dilution : 1
Pressurization Factor : 1.000
Acquisition Date : 2022-01-26 11:17:08
Instrument Method : TO15-SCN2.M
Matrix : AIR
Target Compound
oncen ra on
(PPBV)(PPBV)(PPBV)
oncen ra on
(ug/m3)(ug/m3)(ug/m3)Flag *
Trichloroethene ND 0.0404 0.0350 ND 0.217 0.188
Tetrachloroethene ND 0.0409 0.0350 ND 0.278 0.237
Internal Standards Response
e en on me
(min)
oncen ra on
(PPBV) Flag *
1,4-Difluorobenzene (IS) 1,684,623 14.20 5.16 PASS
Chlorobenzene-d5 (IS) 1,272,771 18.46 4.93 PASS
(ND) = Not Detected
* (J) = Below Calibration Range, (E) = Above Calibration Range, (m) = Manual Integration
IS Acce tance Criteria: RT +- 20 sec Res onse +- 40%
0122-116 TO15_Quant_Ambient - v2
EA# 0122-116R Page 12 of 24
QC Summary Report Enthalpy Analytical, LLC
Sample Name : 5ppbv TO15 LCS
Sample Info : 125mL load; Can #2088; GCMSPrepPg1094
Data File : T2200272.D
Dilution : 1
Pressurization Factor : 1.000
Acquisition Date : 2022-01-26 09:01:41
Instrument Method : TO15-SCN2.M
Matrix : AIR
Target Compound Response
oncen ra on
(PPBV)
ag a ue
(PPBV) % Recovery Flag
Trichloroethene 531,854 4.63 5.06 91.5 PASS
Tetrachloroethene 648,648 5.34 5.12 104.4 PASS
0122-116 QC_SUM-v2
EA# 0122-116R Page 13 of 24
Quantitation Report Enthalpy Analytical, LLC
Sample Name : 5ppbv TO15 LCS
Sample Info : 125mL load; Can #2088; GCMSPrepPg1094
Data File : T2200272.D
Dilution : 1
Pressurization Factor : 1.000
Acquisition Date : 2022-01-26 09:01:41
Instrument Method : TO15-SCN2.M
Matrix : AIR
Target Compound
oncen ra on
(PPBV)(PPBV)(PPBV)
oncen ra on
(ug/m3)(ug/m3)(ug/m3)Flag *
Trichloroethene 4.63 0.0404 0.0350 24.9 0.217 0.188
Tetrachloroethene 5.34 0.0409 0.0350 36.2 0.278 0.237
Internal Standards Response
e en on me
(min)
oncen ra on
(PPBV) Flag *
1,4-Difluorobenzene (IS) 1,895,310 14.20 5.16 PASS
Chlorobenzene-d5 (IS) 1,391,521 18.46 4.93 PASS
(ND) = Not Detected
* (J) = Below Calibration Range, (E) = Above Calibration Range, (m) = Manual Integration
IS Acce tance Criteria: RT +- 20 sec Res onse +- 40%
0122-116 TO15_Quant_Ambient - v2
EA# 0122-116R Page 14 of 24
QC Summary Report Enthalpy Analytical, LLC
Sample Name : 5ppbv TO15 LCS LD
Sample Info : 125mL load; Can #2088; GCMSPrepPg1094
Data File : T2200273.D
Dilution : 1
Pressurization Factor : 1.000
Acquisition Date : 2022-01-26 09:45:12
Instrument Method : TO15-SCN2.M
Matrix : AIR
Target Compound Response
oncen ra on
(PPBV)
ag a ue
(PPBV) % Recovery Flag
Trichloroethene 531,217 4.64 5.06 91.8 PASS
Tetrachloroethene 650,243 5.39 5.12 105.5 PASS
0122-116 QC_SUM-v2
EA# 0122-116R Page 15 of 24
Quantitation Report Enthalpy Analytical, LLC
Sample Name : 5ppbv TO15 LCS LD
Sample Info : 125mL load; Can #2088; GCMSPrepPg1094
Data File : T2200273.D
Dilution : 1
Pressurization Factor : 1.000
Acquisition Date : 2022-01-26 09:45:12
Instrument Method : TO15-SCN2.M
Matrix : AIR
Target Compound
oncen ra on
(PPBV)(PPBV)(PPBV)
oncen ra on
(ug/m3)(ug/m3)(ug/m3) % Diff Flag *
Trichloroethene 4.64 0.0404 0.0350 24.9 0.217 0.188 0.3
Tetrachloroethene 5.39 0.0409 0.0350 36.6 0.278 0.237 1.0
Internal Standards Response
e en on me
(min)
oncen ra on
(PPBV) Flag *
1,4-Difluorobenzene (IS) 1,887,353 14.20 5.16 PASS
Chlorobenzene-d5 (IS) 1,380,306 18.46 4.93 PASS
(ND) = Not Detected
* (J) = Below Calibration Range, (E) = Above Calibration Range, (m) = Manual Integration
IS Acce tance Criteria: RT +- 20 sec Res onse +- 40%
0122-116 TO15_Quant_Ambient - v2
EA# 0122-116R Page 16 of 24
Narrative Summary
EA# 0122-116R Page 17 of 24
Enthalpy Analytical Narrative Summary
Company Mid-Atlantic Associates, Inc. Client # 7N Bloodworth VI
Assessment; R3943.02
Analyst TDD Job # 0122-116R
Parameters EPA Method TO-15 # Samples 3 Canisters
Custody Alyssa Miller received the samples on 1/26/22 after being relinquished
by Mid-Atlantic Associates, Inc. The samples were received at ambient
temperature and in good condition.
Prior to, during, and after analysis, the samples were kept under lock
with access only to authorized personnel by Enthalpy Analytical, LLC.
Analysis The samples were analyzed for trichloroethene (TCE) and
tetrachloroethene (PCE) using the analytical procedures in EPA Method
TO-15, Determination of Volatile Organic Compounds (VOCs) In Air
Collected In Specially-Prepared Canisters And Analyzed by Gas
Chromatography /Mass Spectrometry (GC/MS).
Upon receipt, the canister pressures were measured and recorded. The
canisters were then pressurized with UHP nitrogen and a dilution ratio
was calculated for each (See the Canister and Controller Datasheet
located in the Results section of this report).
The Agilent Technologies Model 7890A, Gas Chromatograph "Tobias"
(S/N CN10823053) equipped with a 5973N Inert MSD (S/N
US03940689) was used for this analysis. All samples and standards
were introduced directly to the analyzer using an Entech 7100A
Preconcentrator.
Calibration The BFB tune analyses associated with the initial and continuing
calibrations met all method acceptance criteria.
The initial calibration (T011722A-TO15) met the 30% RSD criteria.
The initial calibration verification (ICV) met the 70-130% recovery
criteria. The continuing calibrations (CCV) met the 30% difference
criteria. Full calibration data is available upon request.
Chromatographic
Conditions
The acquisition method (TO15-SCN2.M) has not been included in this
level 2 report, however may be made available upon request.
EA# 0122-116R Page 18 of 24
Enthalpy Analytical Narrative Summary
(continued)
QC Notes All internal standard area (IS) responses and retention time criteria were
met for these analyses.
The Laboratory Duplicate (LD) analyzed with this data set met the 25%
difference criteria for all compounds.
The laboratory humid blank associated with the analysis of this sample
did not contain any of the target analytes at a concentration greater than
3 times the MDL value.
The Laboratory Control Samples (LCSs) met the 70-130% recovery
criteria.
The samples were analyzed within the 30-day holding time required by
the method.
Reporting Notes These analyses met the requirements of the TNI Standard. Any
deviations from the requirements of the reference method or TNI
Standard have been stated above.
The results presented in this report are representative of the samples as
provided to the laboratory.
EA# 0122-116R Page 19 of 24
General Reporting Notes
The following are general reporting notes that are applicable to all Enthalpy Analytical, LLC data
reports, unless specifically noted otherwise.
Any analysis which refers to the method as “Type” represents a planned deviation from the
reference method. For instance a Hydrogen Sulfide assay from a Tedlar bag would be labeled
as “EPA Method 16-Type” because Tedlar bags are not mentioned as one of the collection
options in EPA Method 16.
The acronym MDL represents the Minimum Detection Limit. Below this value the laboratory
cannot determine the presence of the analyte of interest reliably.
The acronym LOQ represents the Limit of Quantification. Below this value the laboratory
cannot quantitate the analyte of interest within the criteria of the method.
The acronym ND following a value indicates a non-detect or analytical result below the MDL.
The letter J in the Qualifier or Flag column in the results indicates that the value is between
the MDL and the LOQ. The laboratory can positively identify the analyte of interest as
present, but the value should be considered an estimate.
The letter E in the Qualifier or Flag column indicates an analytical result exceeding 100% of
the highest calibration point. The associated value should be considered as an estimate.
Sample results are presented ‘as measured’ for single injection methodologies, or an average
value if multiple injections are made. If all injections are below the MDL, the sample is
considered non-detect and the ND value is presented. If one, but not all, are below the MDL,
the MDL value is used for any injections that are below the MDL. For example, if the MDL is
0.500 and LOQ is 1.00, and the instrument measures 0.355, 0.620, and 0.442 - the result
reported is the average of 0.500, 0.620, and 0.500 - - - i.e. 0.540 with a J flag.
When a spike recovery (Bag Spike, Collocated Spike Train, or liquid matrix spike) is being
calculated, the native (unspiked) sample result is used in the calculations, as long as the value
is above the MDL. If a sample is ND, then 0 is used as the native amount (not the MDL
value).
The acronym DF represents Dilution Factor. This number represents dilution of the sample
during the preparation and/or analysis process. The analytical result taken from a laboratory
instrument is multiplied by the DF to determine the final undiluted sample results.
The addition of MS to the Sample ID represents a Matrix Spike. An aliquot of an actual
sample is spiked with a known amount of analyte so that a percent recovery value can be
determined. The MS analysis indicates what effect the sample matrix may have on the target
analyte, i.e. whether or not anything in the sample matrix interferes with the analysis of the
analyte(s).
EA# 0122-116R Page 20 of 24
General Reporting Notes
(continued)
The addition of MSD to the Sample ID represents a Matrix Spike Duplicate. Prepared in the
same manner as a MS, the use of duplicate matrix spikes allows further confirmation of
laboratory quality by showing the consistency of results gained by performing the same steps
multiple times.
The addition of LD to the Sample ID represents a Laboratory Duplicate. The analyst prepares
an additional aliquot of sample for testing and the results of the duplicate analysis are
compared to the initial result. The result should have a difference value of within 10% of the
initial result (if the results of the original analysis are greater than the LOQ).
The addition of AD to the Sample ID represents an Alternate Dilution. The analyst prepares an
additional aliquot at a different dilution factor (usually double the initial factor). This analysis
helps confirm that no additional compound is present and coeluting or sharing absorbance with
the analyte of interest, as they would have a different response/absorbance than the analyte of
interest.
The Sample ID LCS represents a Laboratory Control Sample. Clean matrix, similar to the
client sample matrix, prepared and analyzed by the laboratory using the same reagents, spiking
standards and procedures used for the client samples. The LCS is used to assess the control of
the laboratory’s analytical system. Whenever spikes are prepared for our client projects, two
spikes are retained as LCSs. The LCSs are labeled with the associated project number and kept
in-house at the appropriate temperature conditions. When the project samples are received for
analysis, the LCSs are analyzed to confirm that the analyte could be recovered from the media,
separate from the samples which were used on the project and which may have been affected
by source matrix, sample collection, and/or sample transport.
Significant Figures: Where the reported value is much greater than unity (1.00) in the units
expressed, the number is rounded to a whole number of units, rather than to 3 significant
figures. For example, a value of 10,456.45 ug catch is rounded to 10,456 ug. There are five
significant digits displayed, but no confidence should be placed on more than two significant
digits. In the case of small numbers, generally 3 significant figures are presented, but still only
2 should be used with confidence. Many neat materials are only certified to 3 digits, and as the
mathematically correct final result is always 1 digit less than all its pre-cursors - 2 significant
figures are what are most defensible.
Manual Integration: The data systems used for processing will flag manually integrated
peaks with an “M”. There are several reasons a peak may be manually integrated. These
reasons will be identified by the following two letter designations on sample chromatograms,
if provided in the report. The peak was not integrated by the software “NI”, the peak was
integrated incorrectly by the software “II” or the wrong peak was integrated by the software
“WP”. These codes will accompany the analyst’s manual integration stamp placed next to the
compound name on the chromatogram.
EA# 0122-116R Page 21 of 24
Sample Custody
EA# 0122-116R Page 22 of 24
EA# 0122-116R Page 23 of 24
This Is The Last Page
Of This Report.
EA# 0122-116R Page 24 of 24
APPENDIX C - RISK CALCULATIONS FOR SOIL GAS AND INDOOR
AIR
DEQ Risk Calculator - Vapor Intrusion - Resident Soil Gas to Indoor Air
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: 021R3943.02
Exposure Unit ID: SS-1 & SS-2
CAS # Chemical Name:
Soil Gas
Concentration
(ug/m3)
Calculated
Indoor Air
Concentration
(ug/m3)
Target Indoor
Air Conc. for
Carcinogens @
TCR = 1E-06
Target Indoor Air
Conc. for Non-
Carcinogens @
THQ = 0.2
Calculated
Carcinogenic
Risk
Calculated
Non-
Carcinogenic
Hazard
Quotient
127-18-4 Tetrachloroethylene 39804 1194.12 1.1E+01 8.3E+00 1.1E-04 2.9E+01
79-01-6 Trichloroethylene 701 21.03 4.8E-01 4.2E-01 4.4E-05 1.0E+01
Cumulative:1.5E-04 3.9E+01
All concentrations are in ug/m3
Output Form 3B
Carcinogenic risk and hazard quotient cells highlighted in orange are associated with non-volatile chemicals. Since these chemicals do not pose a vapor intrusion
risk, no risk values are calculated for these chemicals.
North Carolina DEQ Risk Calculator
DEQ Risk Calculator - Vapor Intrusion - Non-Residential Worker Soil Gas to Indoor Air
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: 021R3943.02
Exposure Unit ID: SS-1 & SS-2
CAS # Chemical Name:
Soil Gas
Concentration
(ug/m3)
Calculated
Indoor Air
Concentration
(ug/m3)
Target Indoor
Air Conc. for
Carcinogens @
TCR = 1E-06
Target Indoor Air
Conc. for Non-
Carcinogens @
THQ = 0.2
Calculated
Carcinogenic
Risk
Calculated
Non-
Carcinogenic
Hazard
Quotient
127-18-4 Tetrachloroethylene 39804 398.04 4.7E+01 3.5E+01 8.4E-06 2.3E+00
79-01-6 Trichloroethylene 701 7.01 3.0E+00 1.8E+00 2.3E-06 8.0E-01
Cumulative: 1.1E-05 3.1E+00
All concentrations are in ug/m3
Output Form 3E
Carcinogenic risk and hazard quotient cells highlighted in orange are associated with non-volatile chemicals. Since these chemicals do not pose a vapor intrusion
risk, no risk values are calculated for these chemicals.
North Carolina DEQ Risk Calculator
DEQ Risk Calculator - Vapor Intrusion - Resident Indoor Air
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: 021R3943.02
Exposure Unit ID: IA-1
CAS # Chemical Name:
Indoor Air
Concentration
(ug/m3)
Target Indoor
Air Conc. for
Carcinogens @
TCR = 1E-06
Target Indoor Air
Conc. for Non-
Carcinogens @
THQ = 0.2
Calculated
Carcinogenic
Risk
Calculated
Non-
Carcinogenic
Hazard
Quotient
127-18-4 Tetrachloroethylene 2.18 1.1E+01 8.3E+00 2.0E-07 5.2E-02
Cumulative: 2.0E-07 5.2E-02
All concentrations are in ug/m3
Output Form 3C
** - Note that the EPA has no consensus on reference dose or cancer slope factor values for lead, therefore it is not possible to calculate
carcinogenic risk or hazard quotient. Lead concentrations are compared to the National Ambient Air Quality Standard of 0.15 μg/m3.
Carcinogenic risk and hazard quotient cells highlighted in orange are associated with non-volatile chemicals. Risks are calculated for these values if
indoor air concentrations are entered and indoor air screening levels have been established, but it should be noted that detections of these chemicals
are likely not associated with vapor intrusion.
North Carolina DEQ Risk Calculator
DEQ Risk Calculator - Vapor Intrusion - Non-Residential Worker Indoor Air
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: 021R3943.02
Exposure Unit ID: IA-1
CAS # Chemical Name:
Indoor Air
Concentration
(ug/m3)
Target Indoor
Air Conc. for
Carcinogens @
TCR = 1E-06
Target Indoor Air
Conc. for Non-
Carcinogens @
THQ = 0.2
Calculated
Carcinogenic
Risk
Calculated
Non-
Carcinogenic
Hazard
Quotient
127-18-4 Tetrachloroethylene 2.18 4.7E+01 3.5E+01 4.6E-08 1.2E-02
Cumulative: 4.6E-08 1.2E-02
All concentrations are in u /3
Output Form 3F
** - Note that the EPA has no consensus on reference dose or cancer slope factor values for lead, therefore it is not possible to calculate carcinogenic risk
or hazard quotient. Lead concentrations are compared to the National Ambient Air Quality Standard of 0.15 μg/m3.
Carcinogenic risk and hazard quotient cells highlighted in orange are associated with non-volatile chemicals. Risks are calculated for these values if
indoor air concentrations are entered and indoor air screening levels have been established, but it should be noted that detections of these chemicals are
likely not associated with vapor intrusion.
North Carolina DEQ Risk Calculator