NCD981021157_19920928_New Hanover County Airport Burn Pit_FRBCERCLA RD_Final Risk Assessment Report-OCR

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REMEDIAL PLANNING ACTIVITIES AT SELECTED
UNCONTROLLED HAZARDOUS SUBSTANCES DISPOSAL
SITES FOR EPA REGION IV
U.S. EPA CONTRACT NO. 68-W9-0056
FINAL
RISK ASSESSMENT REPORT
FOR THE
NEW HANOVER COUNTY AIRPORT
BURN PIT SITE
WILMINGTON, NORTH CAROLINA
WORK ASSIGNMENT NO. 05-4L5Q
DOCUMENT CONTROL NO.
7740-005•RA-BGDC
September 28, 1992
Prepared for:
U.S. Environmental Protection Agency
Prepared by:
COM Federal Programs Corporation
2030 Powers Ferry Road, Suite 490
Atlanta, Georgia 30339
**COMPANY CONFIDENTIAL**
SEP 2 8 1992
-~LSUTJ
IPA -R!GtON IV
.i'.TLANTA,GA
This document has been prepared for the U.S. Environmental Protection Agency
under Contract No. 68-W9-0056. The material contained herein is not to be disclosed
to, discussed with, or made available to any person or persons for any reason without
the prior expressed approval of a responsible official of the U.S. Environmental
Protection Agency.
COM ARCS IV
Atlanta, Georgia
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TABLE OF CONTENTS
EXECUTIVE SUMMARY ............................. E-1
1.0 INTRODUCTION .............................. 1-1
1.1 Site Description . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
1.2 Site History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-S
2.0 IDENTIFICATION OF CHEMICALS OF
POTENTIAL CONCERN . . . . . . . . . . . . . . . . . . . . . . . . 2-1
2.1 Data Analysis ............................ 2-1
2.2 Chemicals of Concern . . . . . . . . . . . . . . . . . . . . . . . 2-8
2.2.1 Data Limitations . . . . . . . . . . . . . . . . . . . . . 2-15
2.2.2 Selection Criteria . . . . . . . . . . . . . . . . . . . . 2-16
2.2.3 Background Considerations . . . . . . . . . . . . . . 2-17
2.2.4 Selected Chemicals of Concern
for Groundwater ................... 2-18
3.0 EXPOSURE ASSESSMENT ....................... 3-1
3.1
3.2
Characterization of Exposure Setting
Identification of Exposure Pathways
.............. 3-1
3-2
3.2.1 Groundwater Pathways .................. 3-2
3.2.2 Other Pathways . . . . . . . . . . . . . . . . . . . . . . 3-4
3. 3 Quantification of Exposure . . . . . . . . . . . . . . . . . . . . 3-S
3.3.1 Exposure Assumptions .................. 3-S
3.3.2 Exposure Point Concentration . . . . . . . . . . . . . . 3-6
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Section
TABLE OF CONTENTS
( continued)
4.0 TOXICITY ASSESSMENT ........................ 4-1
4.1 Benzene ................................ 4-2
4.2 Chloroform ............................. 4-6
4.3 Chromium . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-8
4.4 1,2-Dichloroethane ........................ 4-14
4.5 Ethylbenzene . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-18
4.6 Lead . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-22
5.0 RISK CHARACTERIZATION ...................... 5-1
5.1 Current Land-Use Conditions .................. 5-1
5.2 Uncertainties ............................. 5-3
6.0 ENVIRONMENTAL ASSESSMENT .................. 6-1
6.1 Scope of the Investigation . . . . . . . . . . . . . . . . . . . . . 6-1
6.2 Site Description and Study Area . . . . . . . . . . . . . . . . . 6-2
6.3 Results of Survey .......................... 6-2
6.4 Conclusions and Limitations . . . . . . . . . . . . . . . . . . . 6-5
7.0 DEVELOPMENT OF RISK-BASED REMEDIATION GOALS .. 7-1
8.0 CONCLUSIONS ............................... 8-1
REFERENCES
APPENDIX A -Confirmation Sampling Results
APPENDIX B - Preliminary Remediation Goals (PRGs)
APPENDIX C -List of Endangered, Threatened or Candidate Species of Flora
and Fauna for the State of North Carolina
APPENDIX D -Sample Calculation for Estimating the Exposure Point
Concentration · ·
II
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Figure
1-1
1-2
2-1
2-2
LIST OF FIGURES
Page
Site Location Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
Site Features Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
Soil Sample Location Map -April, 1991 . . . . . . . . . . . . . . . . . . 2-2
Groundwater Sample Location Map . . . . . . . . . . . . . . . . . . . . . 2-9
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Table
2-1
LIST OF TABLES
First Round Groundwater Data Summary -April 1991 2-3
2-2 First Round Soil Data Summary -April 1991 . . . . . . . . . . . . . . . 2-6
2-3 Second Round Groundwater Data Summary -May 1991 ......... 2-7
2-4 Third Round Groundwater Data Summary -November 1991 . . . . . 2-10
2-5 Third Round Sediment Data Summary -November 1991 . . . . . . . 2-14
2-6 Groundwater Data Summary . . . . . . . . . . . . . . . . . . . . . . . . . 2-19
2-7 Soil Data Summary .............................. 2-21
2-8 Selection of Chemicals of Concern . . . . . . . . . . . . . . . . . . . . . 2-23
3-1
3-2
3-3
3-4
5-1
5-2
6-1
6-2
7-1
7-2
7-3
Potential Pathways of Human Exposure to Contaminants ......... 3-3
Exposure Assumptions Used to Estimate Risk ............... 3-7
Molecular Weights and Henry's Law Constants for
Chemicals of Concern in Groundwater . . . . . . . . . . . . . . . . . . . 3-9
Daily Intake for Chemicals of Concern . . . . . . . . . . . . . . . . . . 3-10
Slope Factors and RfDs Used to Estimate.
Carcinogenic and Non-Carcinogenic Risk ................. 5-2
Human Health Risk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
Identified Flora
Identified Fauna
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.................................
6-3
6-6
Site Remediation Goals (RGs) ......................... 7-3
Groundwater Quality Standard Based Risks ................. 7-4
Summary of Possible Remediation Goals .................. 7-5
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EXECUTIVE SUMMARY
A human health and ecological assessment has been conducted to assess the potential
risk from exposure to chemicals at the New Hanover County Airport Bum Pit Site.
The baseline risk assessment evaluates current conditions in the absence of any further
remedial action at the site. The Potentially Responsible Parties (PRPs) for this site
have completed permanent remedial activities to remove contaminated soil and other
waste materials. This risk assessment addresses only post-remediation conditions for
the site.
Human health risk was quantified for the present baseline condition. The available
data were only sufficient to quantify potential exposure to local residents via
consumption of contaminated drinking water and inhalation of contaminant vapors by
showering.
Soil, surface water, and fugitive dust are not expected to be significant pathways of
exposure for the New Hanover site in its present condition. Contaminated soil has
been removed to achieve the Preliminary Remediation Goals (PRGs) established for
the soils at the site. This would limit the potential for re-entrainment of contaminated
dust or direct contact with contaminated soils. Further, the removal of residual soil
contamination has eliminated the source for future groundwater contamination.
Finally, there are no permanent surface water bodies at the site.
The chemicals of concern in groundwater at the site are benzene, chloroform,
chromium, 1,2-dichloroethane, ethylbenzene, and lead due to toxicity, frequency of
detection, and exceedance of water quality standards. Tentatively Identified
Compounds (TICs) were not evaluated quantitatively since there is a lack of certainty
in identification and absence of critical toxicity values (RfDs and slope factors).
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The estimated carcinogenic human health risk of 1 x 104 for the chemicals of concern
in groundwater is at the upper end of the acceptable risk range of 1 x 104 to 1 x 10-6
as established by the EPA. The estimated carcinogenic risk is the summation of
ingestion and inhalation risks following exposure. Noncarcinogenic effects are not
likely to occur as the hazard index is less than 1. Chromium and ethylbenzene were
evaluated as noncarcinogens.
An endangered species survey performed at the site did not identify the presence of
endangered species of flora or fauna. Specie diversity was limited due to poor habitat
suitability. The dominant observed fauna onsite were opossum, lizard and
perching/songbird species. Flora diversity is typical for a coastal range area which
has undergone significant disturbance, remediation and subsequent revegetation. No
endangered flora species were located onsite.
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1.0 INTRODUCTION
A remedial investigation (RI) was performed by the U.S. Environmental Protection
Agency (EPA) for the New Hanover County Airport Burn Pit Site (New Hanover
Site) located in New Hanover County, Wilmington, North Carolina (EPA, 1992).
History of the site, dating back to 1965, indicated that the area was used for fire
fighter training. The burn pit was used until 1979 by the Cape Fear Technical
Institute and the Wilmington Fire Department for fire fighter training. Jet fuel (JP-4),
drainage from petroleum fuel storage tanks, kerosene, and oil were the major sources
to fuel the fires. Water, carbon dioxide, and dry chemicals were used to extinguish
the fires. In addition, sorbent materials from river spills were also disposed of in the
pit prior to 1982. At least one incident of burning of confiscated drugs by the U.S.
Customs Service is reported to have occurred at the site.
The New Hanover County Department of Engineering conducted sampling at the site
in 1985. Heavy metals and volatile organic compounds (VOCs) were detected in the
pit sludge. The State of North Carolina Division of Health Services also sampled the
bottom of the pit sludge layer. The analytical results also reported heavy metals,
polynuclear aromatic hydrocarbons (PAHs) and VOCs. As a result of both sampling
efforts, the site was proposed for the National Priorities List (NPL) on June 24, 1988
(EPA, 1992). The site was finalized on the NPL in March 1989.
The PRPs were identified and decided to initiate remedial action for the site. The
EPA gave approval to the PRPs to initiate soil removal activities which took place in
November and December 1990. Waste materials, such as surface and subsurface
soils, and structures associated with fire fighter training, were removed and disposed
of offsite. As a result of the soil remediation by the PRPs, the original scope of the
remedial investigation/feasibility study (RI/FS) was changed to focus on residual
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contamination at the site and its potential impact on human health and the
environment.
1.1 SITE DESCRIPTION
The site is located on Gardner Road, west of the New Hanover County Airport in
New Hanover County, 1.5 miles north of Wilmington, North Carolina. The site is
approximately 4 acres in size (see Figure 1-1), the burn pit area occupying about
1,500 square feet.
Land use in the vicinity is commercial, industrial, and residential. According to the
1989 Master Plan by New Hanover International Airport, the entire west side of the
airport, which includes the site, is planned for industrial development with support
from New Hanover County zoning ordinances (Dehn, 1991). Currently there are
rental car maintenance facilities, a closed sawmill/lumberyard, and a trucking
company in the vicinity of the site. The Airport Authority is actively marketing the
available industrial property. The closest residential area is estimated to be
approximately 0.2 miles to the west of the site. This area is separated from the site
by a road, railroad tracks, and a wooded area.
Land immediately surrounding the site to the northeast, north, west and south is
forested with a mixed southern hardwood forest (see Figure 1-2) and is typical of the
coastal plain area. The wooded area extends for 300 to 500 feet west and north and
800 feet south of the site.
Southwest of the site are ten underground storage tanks (USTs), approximately 600
feet away from the site in an area over grown with woods.
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1000 0 ·1000 2000
SCALE IN ft:ET
NORTH CAROLINA
'. . ,. , 2\~; .·.:·:·
~-
.· \\ ,._ \" Ell...,·,'._\'. <:, \ \\
NE:W'•;
COUN_T . --
SITE LOCATION MAP
-NEW HANOVER COUNTY AIRPORT SITE CDM J1'IDaAL PROGIWIS COIPOllAffON WILMINGTON, NORTH CAROLINA •-de._,_ • ..._ ... Flgul'I No. 1 • 1
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SITE FEATURES MAP
-NEW HANOVER COUNTY AIRPORT SITE =CD--'M""'FEDERAL'-'---PR-OG_IIAMS __ co_RPO_IA_TI_O_N WILMINGTON, NORTH CAROLINA . ......,.,c-.o.-r•~-
~ ~ 0 I= ~ ~ a :z < z 0:: u w ~ ~ <.J
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1.2 SITE HISTORY
New Hanover County Airport Bum Pit Site was placed on the NPL on March 30,
1989. The EPA identified the PRPs as New Hanover County (owner of the airport),
the City of Wilmington, Cape Fear Technical Institute, United States Air Force (all of
whom trained fire fighters at the site), and the United States Customs Service (burned
confiscated drugs at the site). Approval was given to the PRPs to perform removal
activities at the site following a signed Administrative Order of Consent from the
EPA in June 1990. All removal activities were overseen by the EPA. The remedial
investigation was then conducted by EPA in 1991.
In November and December 1990, waste materials were removed by the PRPs from
the bum pit and fire fighting area along with contaminated surface and subsurface
soils. Structures associated with fire fighter training activities were dismantled and
removed. These structures consisted of a fuel supply tank and associated underground
piping, a railroad tank car, automobile bodies, and an aircraft mockup. Soil removal
continued in these areas until either no visual contamination remained or groundwater
was encountered. Confirmation soil samples were obtained by the EPA from the
bottom of the excavated areas prior to backfilling to grade with clean soil. The
sampling investigation was performed following removal to confirm the complete
excavation of contaminated soil. These data are summarized in Appendix A from the
EPA's RI Report in January, 1992. Several drums of paint sludge were also found at
the perimeter of the site and were removed and properly disposed of according to the
Resource Conservation and Recovery Act (RCRA) regulations. Groundwater samples
were collected from four temporary monitor wells during the soil sampling activities.
Preliminary Remediation Goals (PRGs) were developed for the site by EPA on
January 23, 1990 which set compound specific concentrations goals for site
contaminants. PRGs were established for groundwater and soil. The soil PRGs were
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also intended to be protective of exposure via both air and soil ingestion pathways.
The derivation of the PRGs by EPA is provided in Appendix B. These criteria are
used to determine if contaminated soils had been completely excavated.
From the results of soil and groundwater confirmation sampling, additional temporary
monitor wells were installed and sampled prior to placement of the permanent monitor
wells. Six permanent monitor wells were installed and sampled in April 1991. Five
soil samples, both surficial and subsurface, were collected in this first round. Two
samples were a re-analysis of previous sampling; the other three were control samples
used as site background in this report. A second round of samples was collected and
analyzed for VOCs in groundwater only. As a result of the recommendations in the
RI by EPA, a third round of groundwater samples was obtained from the site. The
samples were collected to determine baseline conditions at the site since previous
groundwater samples were obtained when the site had not yet stabilized from the
installation and development of the monitor wells.
All data was received by Camp Dresser & McKee Inc. (CDM) in January 1992 to
perform the risk assessment.
1-6
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2.0 IDENTIFICATION OF CHEMICALS OF POTENTIAL CONCERN
2.1 DATA ANALYSIS
Confirmation sampling of soil and groundwater was performed by EPA following the
remedial activities by the PRPs in December 1990. The sediments in the drainage
culverts were also sampled at this time. The results of this analysis were compared to
PRGs to ensure that the PRPs had successfully removed the contaminant source(s)
from the site. Appendix A contains the results of the soil and groundwater
confirmation samples.
In April 1991 the first round of groundwater samples was collected by EPA
immediately after the installation of six permanent wells. Five soil samples were also
collected (Figure 2-1). These data are summarized in Table 2-1 and 2-2 respectively.
The samples were analyzed for metals, pesticides/PCBs, volatiles, and semivolatiles.
Three chemicals, chromium, benzene and ethylbenzene, exceeded groundwater PRGs.
The soil PRGs for inorganics and extractable and purgeable organics were not
exceeded by any soil sample. Two samples are considered control samples, surface
and subsurface. The control samples were obtained in the northeast comer of the site
away from areas where burning activities took place. The second round of
groundwater sampling took place three weeks later in May 1991. The data from this
round was analyzed for volatile organic compounds only. This data is summarized in
Table 2-3.
A third round of samples was obtained by the EPA in November 1991. This most
recent round of samples was intended to characterize baseline stable conditions at the
site and included the collection of 9 samples (1 sediment and 8 groundwater samples).
2-1
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ARMY CORPS
Of ENGINEERS
UST FARM
LEGEND
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-

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-
-EXCAVATION
•
SURFACE SOIL SAMPLE
SUBSURfAC[ SOIL SAMPLE
10.000 gal IANK
(A£wc:MO)
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NH-001-SL.
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CDM Fl!DEaAL PROGRAMS COlll'ORATION
SOIL SAMPLE LOCATION MAP-APRIL, 1991
NEW HANOVER COUNTY AIRPORT SITE
WIUIINGTON, NORTH CAROLINA
liiiii --
SUPPLY
TANK
- -
FIGURE No. 2-1
---... --- - - -- - -
TABLE 2-1
FIRST ROUND GROUNDWATER DATA SUMMARY -APRIL 1991
NEW HANOVER COUNTY AIRPORT SITE
WILMINGTON, NORTH CAROLINA
Inorganic Elements (µg/1)
Aluminum 52,000 56,000
Barium 99 160
Calcium 25,000 22,000
Chromium 82 72
Copper 21 17
Iron 12,000 28,000
Magnesium 3,200 7,700
Manganese 99 360
Nickel 36 23
Potassium 3,200 4,800
Sodium 37,000 37,000
Strontium 250 480
Titanium 180 310
Vanadium 56 73
Yttrium IOU 17
Zinc 52 53
Pesticide/PCB Compounds
J -Estimated value
N -Presumptive evidence of presence of material (tentative identification).
U -Material was analyzed for but not detected. Value is quantitation limit.
-Not detected in the sample.
36,000 46,000
370 290
38,000 28,000
60 58
17 12
40,000 22,000
12,000 7,000
490 130
69 69
9,000 11,000
260,000 250,000
640 160
300 220
63 67
13 17
62 40
~ I!!!! I!!!!!!!! !!!!!! 1!!1!11
58,000 16,000
92 50
6,300 8,600
65 71
14 IOU
11,000 6,100
2,800 2,600
61 59
33 110
3,500 2U
9,700 6,100
56 59
190 85
60 20
IOU IOU
40 40
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--- --- --
F.xlractable Or[anic Comeounds (µg/1)
Bicycloheptyl
[(Butoxycthoxy)ethoxy]cthanol
Dihydrodimcthylindene
Dihydromcthylindene
Dihydronaphthalenone
Dimcthylnaphthalene
2,4-Dimcthylphenol
Dimcthylphenol (Not 2,4-)
Ethyldimcthylbenzene (2 Isomers)
Ethyldimethylbenzene (3 Isomers)
Ethyldimcthylbenzene (6 Isomers)
1-Mcthylnaphthalene
2-Mcthylnaphthalene
2-Methylphenol
Mcthylbenzeneacetic Acid
Methylbenzencmethanol
Mcthylpyrrolidinone
Naphthalene
Naphthalic Anhydride
Tetrahydromcthy!naphthalene
Tetrahydronaphthalene
-
IOU
-
IOJN
4JN
IOU
IOU
!OJN
3JN
20JN
IOU
3JN
4JN
--
TABLE 2-1
(continued)
31N
31N
51N
61N
2.31.
41N
20JN
20JN
601
2.71
20JN
61N
NOTES:
J -Estimated value
N -Presumptive evidence of presence of material (tentative identification). u -Material was analyzed for but not detected. Value is quantitation limit.
-Not detected in the sample.
---I!!!! !!!!!!!I
40JN
51N
421 54 IOU 20U
60JN
20JN
IOOJN
161 IOU ZOU
6.11 5.11 IOU 20U
SOJN
111 91 IOU ZOU
NKAN0l'-027
--- ----
Extractable Orfanic Co/!Y?.ounds (µg/1)
(continued)
Tetrahydrothiophenedioxide
Trimethylbcnzoic Acid (3 Isomers)
Trimethylhexanoic Acid
2 Unidentified Compounds
. 5 Unidentified Compounds
Purfeab/e Orfanic Co/!Y?.ounds (µg/1)
Benzene
Carbon Disulfide
Chloroform
1,2-Dichloroethane
Ethyl Ether
Ethyl Benzene
Ethylmethylbenzene
Methoxymethylpropane
Toluene
Total Xylenes
Trimethylbenzene
Trimethylbenzene (3 Isomers)
Trimethylbenzene (2 Isomers)
NOTES:
J -Estimated value
--
201N
4JN
3.51
25U
2.IJ
IOU
901N
3.31
10.81
--
TABLE 2-1
(continued)
401N
7.91
25U
IOU
IOU
3001N
8.51
IOJN
2.01
25.31
801N
N -Presumptive evidence of presence of material (tentative identification).
U -Material was analyzed for but not detected. Value is quantitation limit.
-Not detected in the sample.
--I!!!!!! I!!!!!! !!!!!I l!!!I!!!
5001N 600JN
7001N 1,000JN
200J
900J
110 110 !U tu
62U 120U I.SJ 12U
25U sou 2.91 1.21
4.41 sou
34 431
2001N
141 5.81 0.891 5U
821 19.41 5U SU
601N
801N
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TABLE 2-2
FIRST ROUND SOIL DATA SUMMARY -APRIL 1991
NEW HANOVER COUNTY AIRPORT SITH
WIU.IJNGTON, NORTH CAROLINA
Inorganic Elemenls (mg/kg)
Aluminum
Arsenic
Barium
Calcium
Chromium
Copper
Iron
Lead
Magnesium
Manganese
Mercury
Strontium
Tin
Titanium
Vanadium
Zinc
Pesticide/PCB Compounds
Extractable Organic Compounds (µg/kg)
Dimethylnaphthalene
Dimelhylphenanthrcne
Ethyldimethylbenzcnc (4 Isomers)
1-Methylnaphthalcnc
2-Methylnaphthalcnc
Mcthylphenaflthrcne (2 Isomers)
Petroleum Product
Trimethylnaphthalcne (4 Isomers)
1 Unidentified Compounds
Purgeab/e Organic Compounds (µg/kg)
Ethyl Benzene
Total Xylencs
Trimethylbenzene (2 Isomers)
590
3.0U
6.7
630
1.4
I.OU
400
6.0
64
4.5
0.065
3.4
2.SU
130
2.1
2.4
l,600U
7,000!
79U
IOI
1,600 2,200
3.0U 1.2
2.7 37
sou 1,700
1.7 3.6
I.OU 10
860 3,300
4.0U 130
37 120
2.2 22
o.osu 0.10
I.OU 8.4
2.SU 4.5
65 66
1.7 4.7
I.OU 66
l,600U l,SOOU
N
52U 72U
52U 72U
~=
J Estimated value
N
u Presumptive evidence of presence of material (tentative identification)
Material was analyzed for but not detected. Value is quantitation lin~it.
Not detected in the sample.
2,500 500
3.0U 3.0U
5.0 2.2
320 84
2.9 1.9
I.OU I.OU
630 230
4.3 2.8
130 24
6.4 5.1
o.osu o.osu
2.5 I.OU
2.SU 2.SU
ISO 150
4.0 1.8
1.7 1.3
l,OOOJN
8001N
3,000JN
SOOJN
2301 l,600U
800JN
N
4,000JN
31J 67U
280U 67U
4,000JN
NHANOOll.024
-.. --- -
Pur.z.eable Qrg_anic ComeJ2.unds (pg/T)
Benzene
Chloroform
1,2-Dichlorocthane
Dimethyl Pentanonc
Ethyl Ether
Ethyl Benzene
Ethylmcthylbenzcnc (2 Isomers)
Mcthoxymethylpropane
Mcthoxypropanol
Methyl Ethyl Ketone
Mctbylpropanol
Tctrahydrothiophcne
Toluene
Total Xylcnea
Trimethylbcnzenc ·
Trimethylbenzcne (2 Isomers)
TrirnethylbcnzenC (3 Isomers)
lli)ID:
J Estimated value
----l!!!!!!l!J l!!!!!!!I
TABLE2-3
SECOND ROUND GROUNDWATER DATA SUMMARY -MAY 1991
NEW HANOVER COUNTY AIRPORT SITE
WILMINGTON, NORTH CAROLINA
1.1 7.7 I.OU I.OU
3.41 1.11 1.61 0.511
s.ou s.ou s.ou s.ou
30JN 200JN
1.21 7.4 s.ou s.ou
20JN
sou sou sou sou
lOJN
s.ou I.SJ s.ou s.ou
4.IJ 21.91 s.ou 0.771
5JN
60JN
N Presumptive evidence of presence of material (tentative identification).
U Material was analyzed for but not detected. Value is quantitation limit.
Not detected in the sample.
!!!!!I !!!!!I !!!!!! I!!!!! !!!!! I!!!!!
31 94
I.SJ 2SU
IOU 2.7J
40JN
9.21 30
lOOJN lOOJN
SOJN
641 2SOU
20JN
20JN
2.SJ 131
9.11 821
SOJN
30JN
m
m
E
• •
I
I
I
I
I
I
I
I
I
I
I
I
I
I
The sample locations for all three rounds of groundwater samples are shown in
Figure 2-2. The sediment sample was obtained at the perimeter of the northern
portion of the site in the path of expected surface water flow from the site during
extreme inclement weather conditions. It is expected that no surficial soil
contamination remains at the site since soil removal activities were successful in
removing contaminated soils based upon the EPA's January 1992 RI .
The EPA obtained six groundwater samples from the same permanent monitor wells
which were previously installed onsite. There are two wells (MWD-001 and
MWS-001) upgradient of the former burn pits, two wells (MWD-002 and MWS-002)
at the location of the former burn pits and two wells (MWS-003 and MWS-004)
cross-gradient of the former pits. One private well located downgradient of the site,
Seagars well (SFC-001), was sampled. A temporary well (MWT-001) was installed
in the third round of sampling in the northern area of the site upgradient from the
former burn pit area. The temporary well was installed to the water table at a depth
of approximately 3 to 4 feet below land surface (bis). The four shallow wells were
installed to a depth of 15 feet bis. The two deep wells reached a depth of
approximately 28 feet bis. A complete scan was run on each sample. The
groundwater data are summarized in Table 2-4 and sediment data are summarized in
Table 2-5.
2.2 CHEMICALS OF CONCERN
The potential chemicals of concern at the New Hanover Site theoretically represent
those contaminants that remain at the site following previous soil remediation by the
PRPs in 1990. The analytical results from all three rounds of samples were reviewed
to determine the appropriate chemicals for evaluation.
2-8
NHAN0()().003
--iii JI ·~ fi n 0 ~ z G) !: m ::JJ ::I :E 0 o C 2! :I: z ~ )I, 0 _z < ro < !; < ~ ~m m a ::JJ ::JJ .z o en z O l> O C i:: :a z "U ;! -t ,-o-< m t )I, ,-0 -0 r ::JJ 0 -"U ~o ~ 'Tl ci C: :a m ~ I)> N ::JJ --t 0 (/) z =i i:: m l> "U ---------------i -r 12s a I--.....--,~ --MW0-001 62.5 125 j eMWT-001 r~ APPROXIMAJ[ SCALE IN rH T -~ ~1?~ • SfC-001 (Approximate location) AHMY CORPS or [NGINE[RS US! FARM ... ,. ~ ""' r--~ r-.-._. ·'{;I~ 10.000 tal ( '~ -. ·-(IO«MD) ' -__, eMWS-004 MWS-003 • r / '-' MW□-00~0 I ·~ , •~-oo>--'/1 ;J ◊~ LEGEND BERM/ROAD ----- --EXCAVAIION MWT - T emporory Monitor Well MWS -Shallow Monitor Well MWO -Deep Monitor Well S£0 -Sediment src -Offsite Monitor Well SUPPlY ,,... -l!!!!!l!!!!I ~
-----
Inorganic Elements (µg/1)
Aluminum
Barium
Beryllium
Calcium
Chromium
Cobalt
Copper
Iron
Lead
Magnesium
Manganese
Molybdenum
Nickel
Potassium
1111 - - ---TABLE 2-4
THIRD ROUND GROUNDWATER DATA SUMMARY -NOVEMBER 1991
NEW HANOVER COUNTY AIRPORT SITE
WILMINGTON, NORTH CAROLINA
16000 6600 6200 4500 4700
260 77 75 12 130
1.4 I.OU I.OU I.OU I.OU
13,000 18,000 18,000 2,800 17,000
34 14 12 4.2 11
2.0U 2.0U 2.0U 2.0U 2.2
11 6.2 5.2 2.0U 3.2
16,000 17,000 16,000 1,200 19,000
22 8.0U 8.0U 8.0U 8.0U
1,900 4,600 4,600 230 3,800
41 280 280 2.6 84
2.0U 2.0U 2.0U 2.0U 2.0U
18 4.9 4.1 4.0U 8.1
1,600 2,900 2,800 540 6,600
-
330
410
I.OU
31,000
30
2.0U
2.7
33,000
8.0U
8,800
350
2.0U
5.8
7,500
Sodium 31,000 43,000 43,000 870 140,000 240,000
Strontium 120 290 290 16 100 350
Titanium 64 44 41 42 19 10
Vanadium 19 9.5 9.3 6.0 41 12
Yttrium 7.7 2.8 2.7 2.0U 12 3.6
Zinc 23 17 IS 2.6 14 6.1
I Estimated value.
N Presumptive evidence of presence of material (tentative identification).
U Material was analyzed for but not detected. Value is quantitation limit.
Not detected in the sample.
-l!!!!!!!!!I l!!!!!!!I
2400 6700 40U
40 34 2.0U
I.OU I.OU I.OU
5,800 6,100 100
8.1 31 2.0U
2.0U 2.0U 2.0U
2.3 3.2 3.4
5,000 1,800 22
8.0U 8.0U 8.0U
1,300 1,700 20U
21 13 2.0U
2.7 2.7 2.0U
s.s 16 4.0U
880 760 400U
10,000 8,400 82,000
40 34 2.0U
17 22 6.1
5.1 6.7 2.0U
2.0U 2.0U 2.0U
9.7 21 7.7
""""""·"'
---------
E-crra.ctabk Organic Compounds (µg/1)
Benzoic Acid
Butoxyethanol
Dicthylbcnzcnc
Dihydrodimcthylindenc
Dihydromcthylindenc
Dihydromethylindcne (2 isomers)
Dihydromethylindcnone
Dihydromethylnaphthalcnc
Dihydronaphthalcnone
Dimetbylbcnzofuranone
Dimcthylbcnzoic Acid
Dimcthyliaobcnzofurandione(2 isomers)
Dimcthylisobcnzofurandione
Dimethylnaphthalene (3 isomen)
Dimcthylnaphthalcne (2 isomers)
2,4-Dimcthylphcnol
Dimcthylpbcnol (not 2,4)
(Dimcthylphcnyl)ethanonc
Ethyldimcthylbenzcnc (2 isomers)
Hcxanoic Acid
Methoxymcthylbcnzene
Mcthyl(propcnyl)benzene
Methylbcnzcneacctic Acid
Mcthylbcnzencacctic Acid (2 isomers)
(Mcthylmethylpropyl)bcnzene
NOTES:
J Estimated value,
6JN
2lN
UN
IOU
!IN
N Presumptive evidence of presence of material (tentative identification).
U Material was analyzed for but not detected. Value is quantitation limit.
Not detected in the sample.
JIN
!IN
2lN
20JN
8JN
7IN
Jom
3.61
JIN
8JN
SIN
JOIN
-TABLE 2-4
(continued)
!IN
51N
IOJN
JOIN
3.41
9JN
2JN
JOIN
20JN
8JN
-
IOU
-
IOOJN
221
70IN
- -
60IN
411
401N
40JN
200IN
1!1!!!11
20IN
IOU
JJN
-l!!!!!!!!I l!!!!!!!l' !!l!!!!I
IOU IOU
NHANOOO °"
--------·
&tractable Qr,g_anic Comeounds (µgfl)
(conJinued)
1-Mcthylnaphthalene SIN 20JN
2-Methylnaphthalcne IOU 19
Methylnaphthalcneacetic Acid
2-Methylphcnol IOU 3.81
3-and/or 4-Mcthylphcnol IOU 2.91
Mcthylpyrrolidinone 40JN
Methylpyrrolidone
Naphthalene I.SJ 21
Naphthalcnca.cctic Acid IOJN
N aphtbalenccarboxylic Acid
N aphthalcnedicarboxylic Acid
Octahydroindcnone
Petroleum Product N N
Tctrahydromethylnaphthalcnc 3JN
Tetrahydronaphthalene 3JN
Tctrahydrothiopbencdioxidc
Tctramethylbcnzenc (2 isomers) 7JN
Tctramcthylbcnzenc 3JN
Trimcthylbenzoic Acid (3 isomers) 60JN
Trimethylbcnzoic Acid, Methyl Ester 3JN
Trimethylbcnzoic Acid (2 isomers) 20JN
Trimcthylphenol
4 Unidentified Compounds
7 Unidentified Compounds IOOJ
NOTES:
J Estimated value.
N Presumptive evidence of presence of material (tentative identification).
U Material was analyzed for but not detected. Value is quantitation limit.
Not detected in the sample.
TABLE2-4
(continued)
20JN
18
20JN
3.71
2.61
20JN
20
IOJN
9JN
3JN
N
41N
6IN
40JN
2lN
501
_,_
60JN
IOU IOU
IOU IOU
IOU IOU
IOU 111
40lN
N
200JN
--!!!!!!!I l!!!!!!!!!!!I l!!!!!!!!I
IOU IOU IOU IOU
IOU IOU IOU IOU
IOU IOU IOU IOU
IOOU IOU IOU IOU
N
400lN
---_, -- -
Pesticide/PCB Comll!!,unds
Puaeable Qrz.anic Comeoimds (µg/1)
Benzene 4.2 7.7
Ethyl Benzene 4.5] 8.8
Ethyl Ether 70JN 200JN
Ethylmcthylbenzene (2 isomers) 20JN
Mcthoxymcthylpropane
0-Xylene 9.4 16
Tert-Butyl Alcohol
Tetrahydrothiophene
Toluene 5.0U I.II
Trimethylbenzcne (2 isomers) 20JN
Trimctbylbcnzcne (3 isomers) 50JN
Trimethylbenzenc
(M-and/or P-)Xylene 3.11 9.0
NOTES,
J Estimated value.
N Presumptive evidence of presence of material (tentative identification).
U Material was analyzed for but not detected. Value is quantitation limit.
Not detected in the sample.
TABLE2-4
(continued)
7.8
8.7
200JN
lOJN
17
I.II
50JN
8.9
--
I.OU 74
5.0U 28
lOOJN
5.0U 7.81
40JN
JOIN
5.0U 25U
JOIN
5.0U 25U
----
110 I.OU I.OU I.OU
31] 5.0U 5.0U 5.0U
200JN
271 5.0U 5.0U 5.0U
5.9] 5.0U 5.0U 5.0U
60JN
39] 5.0U 5.0U 5.0U
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
TABLE 2-5
THIRD ROUND SEDIMENT DATA SUMMARY -NOVEMBER 1991
NEW HANOVER COUNTY AIRPORT SITE
WILMINGTON, NORTH CAROLINA
Inorganic Elements (mg/kg)
Aluminum
Barium
Calcium
Chromium
Copper
Iron
Lead
Magnesium
Manganese
Strontium
Titanium
Vanadium
Yttrium
Zinc
Pesticide/PCB Compounds
Extractable Organic Compounds (µg/kg)
Bromodiphenylpropanedione
Hexahydrodimethyl(methylethyl)naphthalene
Octahydromethylmethylene(methylethyl)naphthalene
Phenol
I Unidentified Compound
Purgeable Organic Compounds (µg/kg)
Toluene
(M-and/or P-) Xylene
NOTES:
J -Estimated value
N -Presumptive evidence of presence of material (tentative identification).
-Material was analyzed for but not detected.
2-14
3,000
8.7
220
3.5
4.6
670
26
82
3.0
2.1
59
5.8
I.I
8.0
300JN
700JN
400JN
180J
3,000J
6.IJ
6.91
NHANC09.02S
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
2.2.1 DATA LIMITATIONS
It is important to note that the data available for the risk assessment is limited to
groundwater, as only a few soil and one sediment sample was obtained from the site.
The soil data are not sufficient for a quantitative risk assessment, however, a
qualitative assessment is needed. During the removal action by the PRPs, the
surrounding contaminated soils around the burn pit, various training areas, the storage
tank, and the underground piping, were removed until either clean soil, noted by
visual observation, or groundwater was encountered. Confirmation sampling,
obtained at the bottom of the excavation pits, verified the removal of contaminated
soils. Surficial soil samples in those areas could not be collected at that time since all
contaminated soils had been removed (EPA, 1992). No surficial soil samples were
collected horiwntally from the excavated areas. The excavation pits were filled to
grade with clean soil, which is what remains at the surface of the burn pit site today.
The April 1991 soil sampling event included two control soil samples, which
contained several inorganic compounds. The other three samples in this first round
were below the soil PRGs established for the hazardous constituents at the site. The
sediment sample collected in the third round is addressed as if it were a soil sample
since there are no permanent surface water bodies onsite. This sample was obtained
in the northwest corner of the site upgradient from the former burn pit site where
samples had not been previously collected. The sample was obtained in a ditch which
could provide a surficial path for off site contaminant migration. The analytical results
did not demonstrate significant site-related contaminants. The results of this sample
did not exceed soil PRGs. However, the groundwater results demonstrated several
chemicals above the PRGs for groundwater. Therefore, the quantitative risk
assessment is based on exposures due to residual contamination in groundwater only.
2-15
NHAN009 .003
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
2.2.2 SELECTION CRITERIA
Approximately 200 chemicals were analyzed in each groundwater and sediment
sample; most analytes were not detected. For the compounds detected, a screening
process was used to determine the chemicals of concern for quantitative evaluation in
the risk assessment. The screening process consisted of the following criteria:
•
•
•
•
Was the chemical frequently detected above quantitation limits?
The frequency of detection determines whether or not a compound is
present at the site. A majority of the contaminants analyzed in each
sample were not detected above analytical laboratory quantitation
limits. Any compound detected above the sample quantitation limit
would be retained for evaluation in the risk assessment. The minimum
quantitation limit was used in the analysis of the samples to obtain the
PRGs.
Was the concentration of the chemical in groundwater above drinking
water standards?
Groundwater concentrations were compared to the State of North
Carolina Drinking Water Standards and Federal Drinking Water
regulations.
Was the concentration of the chemical in soil above naturally occurring
background levels?
Since there is no permanent surface water onsite, the sediment sample
was treated as a soil sample and compared to literature background soil
concentrations. Trace constituent concentrations in groundwater are
also presented in this report as several inorganics are constituents of
groundwater and naturally occur.
Were the concentrations in soil or groundwater above proposed RCRA
action levels?
Groundwater and sediment data were compared with proposed
corrective action levels developed under RCRA (EPA, 1990). These
action levels are intended for use as a screening tool, however, they
only consider exposure to a single chemical.
All detected concentrations were evaluated in the risk assessment. However, several
samples were qualified and flagged with a "J" which indicates positive identification,
2-16
NHAN009.003
0
m
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
but an estimated concentration. These values are used as actual detected
concentrations. The estimated results could add a degree of uncertainty by either
underestimating or overestimating the true value; but qualified data can be used in a
quantitative risk assessment (EPA, 1989). Several samples contained compounds that
were qualified with an "N" which denotes presumptive evidence of the presence of
that material in a sample, a tentative identification. The identification and
concentration of the chemical is uncertain. Chemicals qualified with a "JN" were not
used in the quantitative risk assessment as they are compounds with estimated
concentrations with tentative identification in that sample.
2.2.3 BACKGROUND CONSIDERATIONS
Many of the inorganics detected onsite are naturally occurring. A comparison of
these concentrations to background levels in soil or groundwater is necessary to
determine if there is significant contamination. For example, in groundwater,
hardness in water is primarily caused by calcium and magnesium, and occasionally
heavy metals such as iron can contribute significantly to total water hardness. The
maximum concentration of manganese in groundwater was 490 µg/1. The
concentration exceeded the secondary maximum contaminant level (SMCL) but is
within the range of background of Oto 1,500 µg/1 for New Hanover County
(U.S.G.S., 1970). The SMCL is a nonenforceable drinking water goal based on the
aesthetic quality of water, such as taste, odor, or color. Other trace constituents in
groundwater such as cobalt, strontium, titanium, vanadium, and yttrium (for which
there are no drinking water standards) are commonly found in groundwater (Driscoll,
. 1986). These concentrations are included in Table 2-6 for those inorganics that do
not have health-based drinking water criteria. The New Hanover site is located in a
coastal plain and groundwater in the lower aquifer has not been developed due to high
salinity. High levels of sodium and potassium in a few onsite wells most likely
reflect this condition. The inorganics detected in groundwater that do not have a
2-17
NHAN009.003
0
0
m
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
drinking water standard or toxicity value are not considered quantitatively in this risk
assessment.
Several metals were detected above soil background concentration ranges. High
levels of calcium and magnesium, which contribute to water hardness, were above
soil background. Aluminum, iron and titanium were also detected above background.
The presence of aluminum can be characteristic of an area based on the mineralogy,
or it can demonstrate contamination. Iron and titanium also exceeded soil background
ranges. A commonly found mineral in beach sands, known as ilmenite, may be
attributable to the elevated levels of these two metals. Ilmenite is composed largely
of iron and titanium (Deer, et al., 1982). The metals previously cited as being above
background, are present in the control samples. One most recent sediment sample
may not be representative of the presence of these metals throughout the entire site,
therefore they are not evaluated in this risk assessment. In addition, there are no
toxicity values. Previous sediment samples collected in December 1990 did not result
in significant contamination. The data for the December 1990 samples, BP-01 and
BP-02, can be found in Table A-1 in Appendix A.
2.2.4 SELECTED CHEMICALS OF CONCERN FOR GROUNDWATER
The proposed RCRA Action Levels are used as a screening tool to help determine the
chemical(s) of concern for this risk assessment. These proposed action levels are
based on the toxicity value of the chemical (i.e., RID or slope factor) and a
residential exposure scenario, however, only exposure to a single chemical is
considered. These proposed action levels are included in Table 2-6 and Table 2-7
along with other criteria relevant for determining the chemicals of concern in this risk
assessment. The results of this screening process is summarized in Table 2-8. Based
on the previous criteria, site history, and all three rounds of sampling results, the
potential chemicals of concern retained for the risk assessment are:
2-18
NHAN009.003
- --- ---
Inorganic Ekmems (µg/L)
Aluminum 13114
Barium 13no
Beryllium 1/14
Calcium 14114
Chromium 13114
Cobalt 1/14
Copper 12/14
Iron 14114
Lead 1/14
Magnesium 13114
Manganese 13114
Molybdenum 2/14
Nickel 12/14
Potassium 12/14
Sodium 14114
Strontium 13114
Titanium 14114
Vanadium 13114
Yttrium 7114
Zinc 14114
NOTES:
-----TABLE 2-6
GROUNDWATER DATA SUMMARY
NEW HANOVER COUNTY AIRPORT SITE
WIIMINGTON, NORTH CAROLINA
23,479.2 58,000
155.7 410
1.4 1.4
15,835.7 38,000
41.6 82
2.2 2.2
9.42 21
15,151.6 40,000
22 22
4,433.1 12,000
153.1 490
2.7 2.7
33.2 110
4,356.7 11,000
82,505.0 260,000
199.6 640
107.8 310
33.7 73
10.4 17
27.7 62
• Groundwater action level calculated for the compound with a toxicity value using the RCRA guidance.
-Treatment technique action level (EPA, 1991a).
-Not available.
@ Established drinking water standard.
References: 1North Carolina Administrative Code (NCAC), 1989.
l!!!!!!!!I I!!!!!
50-200
1,000 1,000
4
50 50
1,000 1,30('.r
300 300
50 15-
50 50
150 100
5,000 5,000
2Drinking Water Regulations and Health Advisories, EPA, 1991. (Effective date for beryllium standard is July 17, 1992.)
'Resource Conservation Recovery Act (R.CRA) EPA, 1990.
'Driscoll, 1986.
I!!!!!
@
0.008
@
@
@
3,500
140'
700
245"
@
==
<100
@
<100
>5,000
@
<100
@
10-10,000
@
>5,000
<100
<100
@
10-10,000
>5,000
10-10,000
<100
<100
<100
@
""""""·'""
;;;a
- - - ----
Purg~abk Organic Compounds (µg/L)
Benzene 12/20
Carbon Disulfide 1no
Chloroform 8no
1,2-Dichloroethane 2/20
Ethylbenzenc 12/20
Toluene 9nO
Xylene,, total llnO
Extractable Qrg_anic Co!EJ!.ounds (µg/L)
2,4-Dimethylpbenol 6/14
Methyl ethyl ketone 1/14
2-Mctbylnapbthalene 3/14
3-or 4-Methylphcnol 1/14
2-Methylphcnol 4/14
Naphthalene 5114
NOTES:
--
46.8
1.8
1.9
3.6
17.9
5.2
28.3
27.5
64
13.7
2.9
4.4
13.9
- -
TABLE2-6
(continued)
llO
1.8
3.4
4.4
43
14
82
54
64
19
2.9
6.1
21
• Groundwater action level calculated for the compound with a toxicity value using the RCRA guidance.
-Treatment technique action level (EPA, 1991a).
-Not available.
@ Established drinking water standard.
References: 1North Carolina Administrative Code {NCAC}, 1989.
--l!!!!!!!I
5
0.19 100
0.38 5
29 700
1,000 1,000
400 10,000
170
2Drinking Water Regulations and Health Advisories, EPA, 1991. (Effective date for beryllium standard is July 17, 1992.)
3Resource Conservation Recovery Act (RCRA) EPA, 1990.
4Driscoll, 1986.
!!!!!9 == &iii iiil
@ @
4,000
6
.@
4,000
10,000 @
70,000 @
700'
2,000
2,000
2,000
140"
Nl{AN009.00'
------11!!1!1
ln.oa:,anic EJemmzs (mg/kg)
Aluminum 4/4
Arsenic 1/4
Barium 4/4
Calcium 4/4
Chromium 4/4
Copper 214
Iron 4/4
Lead 4/4
Magnesium 4/4
Manganese 4/4
Mercury 1/4
Strontium 3/4
Tin 1/4
Titanium 4/4
Vanadium 4/4
Yttrium 1/4
Zinc 4/4
NOTES:
-Not available.
References: 1Shacklenc and Boemgen, 1984.
I!!!!!!! !!!!!I I!!!!! I!!!!!! !!!!!!!
2,050
1.2
13.2
581
3
7.3
1,207.5
40.8
89
9.1
0.1
4.3
4.5 ·
·(06.3
4.1
1.1
19.3
TABLE 2-7
SOIL DATA SUMMARY
NEW HANOVER COUNTY AIRPORT SITE
WILMINGTON, NORTH CAROLINA
3,000 590
1.2
37 6.7
1,700 630
3.6 1.4
10
3,300 400
130 6
130 64
22 4.5
0.1 0.065
8.4 3.4
4.5
150 130
5.8 2.1
1.1
66 2.4
2Resource Conservation Recovery Act (RCRA) EPA, 1990.
== == == !ilia
1,600 0.7 to 10
<0.1 to 73 1.7
2.7 10 to 1,500
0.01 to 28
1.7 I to 1,000 15
<lto700
860 0.01 to > 10
<10to300 500
37 0.005 to 5
2.2 <2 to 7,000
0.01 to 3.4
<5 to 700
<0.l to 10
65 0.007 to 1.5
1.7 <7 to 300
<10to200
<5 to 2,900
--- -
l!!l!!I l!!!!9
Purgeabk ~anic Compounas 1.µglig)
Ethyl Benzene 1/4 31
Toluene 1/4 6.1
Total Xylenes 1/4 6.9
Extractabk ~anic Compo@as 1kg)
2-McthylnaphtbaJene 1/4 230
Phenol 1/4 180
NOTES,
-Not available.
References: 1Shacklctte and Boemgen, 1984.
1Resourc:e Conservation Recovery Act (RCRA) EPA, 1990.
!!!!9
31
6.1
6.9
230
180
!!!!!I
TABLE 2-7
( continued)
m!!
10
== ;;a liliiiii liliiiii
8x10' 2x10'
2xl07 7.9xl0'
2x10' 3x10'
8,200
5x107
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Benzene
Chloroform
Chromium
1,2-Dichloroethane
Ethylbenzene
Lead
Aluminum
Barium
Beryllium
Calcium
Carbon Disulfide
Cobalt
Copper
2,4-Dimethylphenol
Iron
Magnesium
TABLE 2-8
SELECTION OF CHEMICALS OF CONCERN
NEW HANOVER COUNTY AIRPORT SITE
WILMINGTON, NORTH CAROLINA
Exceeded NCAC and Federal Water Quality Standards, a carcinogen.
Exceeded NCAC Groundwater Quality Standard, a carcinogen.
Exceeded NCAC and Federal Water Quality Standards, a carcinogen.
Exceeded NCAC Groundwater Quality Standard, a carcinogen.
Exceeded NCAC Groundwater Quality Standard, a noncarcinogen.
Exceeded the Federal Drinking Water Standard, a carcinogen.
No toxicity value.
Below NCAC and Federal Water Quality Standards, within soil background
range.
Below Federal Drinking Water Standard, not detected in soil.
Attributable to water hardness, no toxicity value.
Below proposed RCRA Action Level in groundwater, not detected in soil.
Below trace constituent concentration in groundwater, no toxicity value.
Below NCAC and Federal Water Quality Standards, within soil background
range.
Below proposed RCRA groundwater action level, not detected in soil.
Attributable to water hardness, no toxicity value.
Attributable to water hardness, no toxicity value.
2-23
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D Manganese
D Methy ethyl ketone
D 2-Methylnaphthalene
2-Methylphenol
E 3-or 4-Methylphenol
Molybdenum
E
Naphthalene
Nickel
I Phenol
Potassium
m Sodium
Strontium
I Titanium
Toluene
I Vanadium
I Xylenes
I Yttrium
Zinc
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TABLE 2-8
( continued)
Below proposed RCRA groundwater and soil action level, trace constituent in
groundwater, within soil and groundwater background range.
Below NCAC Water Quality Standard and proposed RCRA Groundwater Action
Level, not detected in soil.
Three detects in groundwater, not detected in soil, no toxicity value.
Below proposed RCRA groundwater action level, not detected in soil.
Below proposed RCRA groundwater action level, not detected in soil.
Below proposed RCRA groundwater action level, not detected in soil.
Below proposed RCRA groundwater action level, not detected in soil.
Below NCAC Water Quality Standard, below proposed RCRA groundwater action
level, not detected in soil.
Not detected in groundwater, below proposed RCRA soil action level.
Attributable to saline conditions, not detected in soil.
Attributable to saline conditions, not detected in soil.
Within trace constituent concentration in groundwater, within soil background
range, no toxicity value.
Trace constituent in groundwater, detected in soil, no toxicity value.
Below proposed NCAC and Federal Water Quality Standards, below RCRA soil
action level.
Below proposed RCRA groundwater action level, trace constituent in
groundwater, below soil background range.
Below NCAC and Federal Water Quality Standards, below proposed RCRA soil
action level.
Trace consfituent in groundwater, below soil background range, no toxicity value.
Below NCAC and Federal Water Quality Standards, within soil background
range.
2-24
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Benzene
Chloroform
Chromium
1,2-Dichloroethane
Ethylbenzene
Lead
Several values for ethylbenzene exceeded the NCAC standard (4 of 20). The standard
is not risk based, but instead, based on the odor threshold for ethylbenzene in water
(ATSDR 1990, page 59). The concentrations that exceeded the NCAC standard are
an order of magnitude below the risk-based estimate of 700 µg/1, the maximum
contaminant level (MCL) for drinking water. The NCAC standard is an applicable or
relevant and appropriate regulation (ARAR) for the site, and for this reason,
ethylbenzene is retained as a chemical of concern.
2-25
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3.0 EXPOSURE ASSESSMENT
3.1 CHARACTERIZATION OF EXPOSURE SETTING
Current onsite land use is limited. The burn pit site is currently not being used for
industrial, commercial, or residential purposes. The site is an open area, though a
fence with locked gates blocks each driveway and may deter trespassers on the
property. It is located at the New Hanover County Airport, however, public access is
restricted to this area. Airport personnel provide some security for the site.
According to the 1989 Master Plan for the airport, the site is in an area which is
designated for industrial development (Dehn, 1991). New Hanover County received a
grant in 1982 to construct a water/sewer system to serve this area. All industrial
development at the airport will be connected to the system as wells are not permitted
(Dehn, 1991).
The nearest residential area is 0.2 miles west of the site. The land immediately
adjacent to the west of the site is heavily forested and separated from the residents by
railroad tracks and a road. The site is completely surrounded by elevated roads
which form a berm around the site. Outside of the elevated roads is a perimeter
ditch. Although perimeter ditches and drainage culverts are present, surface water at
the site either infiltrates or evaporates with little or no offsite surface water drainage
(EPA, 1992). The groundwater elevations near the middle of the site appear to
indicate a somewhat mounded water table condition which may be due to the recent
removal activities· altering the hydraulic properties of the site. Regional groundwater
flow direction is generally to the southwest (EPA, 1992).
3-1
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3.2 IDENTIFICATION OF EXPOSURE PATHWAYS
An exposure pathway is the route or mechanism by which a chemical agent goes from
a source to an individual or population. Each exposure pathway includes the
following:
· • A source and mechanism of chemical release to the environment
• A transport medium (e.g., soil or groundwater)
• An exposure point (where a receptor will contact the medium)
• An exposure route (i.e., ingestion, inhalation, or dermal contact)
A pathway is considered complete when all of the above elements are present. The
potential routes of exposure and potential receptors for each exposure medium, at the
New Hanover Site, are evaluated and summarized in Table 3-1.
3.2.l GROUNDWATER PATHWAY
All rounds of sampling showed groundwater contamination and it is assumed that
exposure via consumption of groundwater and inhalation of volatile compounds during
showering will be complete pathways in the future. There are residents within a
three-mile radius of the site who obtain drinking water from private wells, and other
area residents who obtain drinking water from a local community well system. The
potential exists for migration of contaminants from the site to domestic wells.
Currently, there are no known private or public wells affected by the site. Results
from the private well, SFC-001, located do\J.'.ngradient from the site, indicate that no
contaminants have migrated offsite. However, current domestic use of the shallow
3-2
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TABLE 3-1
POTENTIAL PATHWAYS OF HUMAN EXPOSURE TO CONTAMINANTS
NEW HANOVER COUNTY AIRPORT SITE
WILMINGTON, NORTH CAROLINA
Inhalation of dust
and volatiles
Inhalation of volatiles
Ingestion; dennal contact
Dermal absorption
Incidental ingestion;
dennal absorption
None
Local population
(trespassers)
Local residents
Users of water from
municipal, industrial,
commercial, or residential
wells
Local population
(trespassers)
Local population
(trespassers)
Not applicable.
3-3
Unlikely. Contaminated surficial
and subsurface soils removed.
Bum pit and other areas show
signs of revcgetation.
Yes. Volatiles present in
groundwater. Potential for
exposure by volatilization of
contaminants during a shower.
Potential future exposure.
Currently no known contaminated
residential wells. Private wells
are within a three mile radius of
the site.
Unlikely. Sediments are not
exposed for direct contact.
Sediments are not contaminated
with VOCs or PAHs.
Unlikely. Contaminated surficial
and subsurface soils removed.
Confirmation samples verify
appropriate cleanup. Site under
jurisdiction of airport security.
No. No permanent surface water
bodies onsite.
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aquifer makes it reasonable to assume that contaminated groundwater may reach
offsite wells in the future.
One sediment sample obtained from the site was evaluated as a soil sample. The
detected chemicals are inorganics. High concentrations for several metals may be
attributable to the site. Two other sediment samples (BP-01 and BP-02) were
collected during the December 1990 confirmation sampling event. The only detected
chemicals are several inorganics, which, when compared to PRGs and general
background soil concentrations are not at levels of concern. The sediment data from
the December 1990 sampling is presented in Appendix A, Table A-1. All other soil
samples obtained in the confirmation sampling round were collected at the bottom of
the excavation pits. Three other soil sample results from the first round were also
below the PRGs.
3.2.2 OTHER PATHWAYS
There is no onsite surface water other than periodic wet areas due to ponding of
precipitation. In addition, contaminated surficial and subsurface soil was removed in
the 1990 remediation by the PRPs. Soil confirmation samples obtained from the
bottom of the excavation pits demonstrated no contaminants at levels of concern (see
Tables A-1 and A-2, Appendix A) (EPA, 1992). Excavation pits were backfilled to
grade with clean soil. Since that time, local vegetation has grown over those areas,
so that the burn pit is no longer discernible from the rest of the site. The remediation
activities are believed to have removed all major sources of surficial and subsurface
contamination. This would suggest that contact with contaminated surface soils or re-
entrainment of contaminated dust with subsequent inhalation are not expected to be
associated with significant risk. Thus, the lack of surface soil data is not expected to
have a significant impact on overall risk.
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3.3 QUANTIFICATION OF EXPOSURE
3.3.1 EXPOSURE ASSUMPTIONS
Ingestion of Drinking Water
Current EPA guidance (EPA, 1989) is used to derive the following equation to
estimate the daily intake via drinking water.
low =
where:
low =
Cow =
IR =
Bio -
EF =
ED =
BW =
DY =
YL =
Inhalation of Vapors
(C 0w)(IR)(Bio)(EF)(ED)
(BW) (DY) (YL)
daily intake (mg/kg/day);
contaminant concentration in groundwater (mg/I);
ingestion rate (I/day);
relative bioavailability factor (unitless);
exposure frequency (days/yr);
exposure duration (years);
average body weight (kg);
days in a year (365 days/year); and
years in lifetime or the period over which risk is being estimated
(70°year lifetime for carcinogens, 30 years for noncarcinogens).
Recent monitoring studies and modeling analyses have indicated that exposure to
volatile compounds in contaminated water supplies can occur not only through
ingestion, but also through inhalation. Volatile organic compounds (VOCs) are
operationally defined as compounds with a Henry's law constant greater than 10-3 atm
m3/mol and molecular weights less than 200. Monitoring studies involving actual
3-5
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showering with contaminated water has confirmed the conclusion that showering
exposure is equivalent to exposure from ingesting two liters of contaminated water per
day (EPA, 1991c). This recommendation was established by the Risk Assessment
Forum as the result of a colloquium held regarding the estimation of exposure to
voes during showering.
Exposure assumptions are listed in Table 3-2. The ingestion rate, exposure
frequency, and exposure duration are all upper range estimates to ensure that the
exposure estimates are reasonable maximums. The reasonable maximum exposure
(RME) is the maximum exposure that is reasonably expected to occur at a site. The
assumptions used in the daily intake estimate, in combination with the other variables,
will result in the RME and is expected to occur under both current and future land-
use conditions.
3.3.2 EXPOSURE POINT CONCENTRATION
The data set for the chemicals of concern include qualified data to estimate the
exposure point concentration. For those data points that are nondetect, half the
detection limit is used. The arithmetic average and standard deviation are estimated
for log transformed data for each chemical of concern. The 95 percent upper
confidence limit (UCL) value is derived using the average and standard deviation and
the resultant concentration is used in estimating risk. However, should the
concentration be higher than the maximum detected concentration, the maximum
detected concentration is applied. Lead was detected once in groundwater and the
single value is used to estimate the daily intake in this case. Appendix D provides a
sample calculation.
3-6
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TABLE 3-2
EXPOSURE ASSUMPTIONS USED TO ESTIMATE RISK
NEW HANOVER COUNTY AIRPORT SITE
WILMINGTON NORTH CAROLINA
Body Weight -Adult 70 kg
Drinking Water Ingestion Rate -Adult 2 Uday
Exposure Frequency 350 days/year
Exposure Duration 30 years
Bioavailability/ Absorption Ingestion 1.0
Inhalation 1.0
Reference: EPA, 1989
3-7
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The daily intake by inhalation is estimated for those compounds that readily volatilize
from groundwater. EPA suggests two criteria for determining if a compound is
readily volatilized, 1) Henry's Law constant of greater than 1 x 10-5 atm-m3/mole and
2) molecular weight of less than 200 g/mole (EPA, 1991d). Molecular weights and
Henry's law constants are presented in Table 3-3. Exposure via inhalation is thus
estimated as being equal to the oral daily intake.
The daily intake of the chemicals of concern via consumption of contaminated
drinking water and inhalation of vapors during a shower is summarized in Table 3-4.
3-8
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TABLE 3-3
MOLECULAR WEIGHTS AND HENRY'S LAW CONSTANTS FOR
CHEMICALS OF CONCERN IN GOUNDWATER
Benzene
Chromium
Chloroform
NEW HANOVER COUNTY AIRPORT SITE
WILMINGTON, NORTH CAROLINA
78 5.59 X lQ·3
52 Not Available
119 4.05 X 10-3
1,2-Dichloroethane 99 1.18 X 10-3
Ethylbenzene 106 8.44 X 10-3
Lead 207 Not Available
3-9
Yes
No
Yes
Yes
Yes
No
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Benzene
Chloroform
Chromium
1,2-Dichloroethane
Ethylbenzene
Lead
NOTES:
TABLE 3-4
DAILY INTAKE FOR CHEMICALS OF CONCERN
NEW HANOVER COUNTY AIRPORT SITE
WILMINGTON, NORTH CAROLINA
12/20 0.110 1.3 X 1()"3
8/20 0.011 1.3 X 1(}"
13/20 0.082 2.2 X 1()"3
2/20 0.007 8.2 X 1()"5
12/20 0.021 5.8 X 1(}"
1/20 0.022 2.6 X 1(}"
• 95% Upper Confidence Limit (UCL) Concentration.
• Estimated as being equal to the daily intake by ingestion (EPA, 1991c).
1.3 X 10-3
1.3 X 10'
_,
8.2 X 1()"5
5.8 X 1(}"
_,
' Indicates that the daily intake is not estimated since this compound is not considered volatile.
3-10
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4.0 TOXICITY ASSESSMENT
The following is a discussion of the toxicological information available for the
chemicals of concern at the New Hanover County Airport Site. The information for
each chemical will be presented as follows:
• Toxicokinetics
• Qualitative Assessment of Toxicity
• Quantitative Assessment of Toxicity
• Criteria and Standards
EPA assigns weight of evidence classifications to potential carcinogens. Under this
system, potential carcinogenic chemicals are classified as belonging to Group A,
Group Bl, Group B2, Group C, Group Dor Group E. Group A chemicals (human
carcinogens) are agents for which there is sufficient evidence to support the causal
association between exposure to the agents in humans and cancer. Group Bl and B2
chemicals (probable human carcinogens) are agents for which there is limited
evidence of carcinogenicity in animals, Group C and Group D chemicals (not
classified as to human carcinogenicity) are agents with inadequate human and animal
evidence of carcinogenicity. Group E (no evidence of carcinogenicity in humans) are
agents for which there is no evidence of carcinogenicity in at least two animal studies
or in both epidemiological and animal studies. Reference doses (RfDs) are also
available for potential carcinogenic compounds that have noncarcinogenic effects as
well. The RfDs, expressed in mg/kg/day, are estimates of the daily exposure to the
human population that is unlikely to pose an appreciable risk of deleterious effects
during a lifetime.
4-1
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4.1 BENZENE
The EPA has placed benzene in Group A, a human carcinogen based on sufficient
evidence of carcinogenicity in humans from epidemiological studies.
TOXICOKINETICS
The most frequent route of human exposure to benzene is via inhalation. The lung
absorption factor has been shown to be about 50 percent for continuous doses of 50 to
100 ppm for several hours (ATSDR, 1987). Studies with laboratory animals confirm
that benzene is rapidly absorbed by the oral route, with oral doses between 9 and 30
grams causing fatality in humans. In animals (i.e., rats, mice, and rabbits) greater
than 90 percent oral absorption has been shown.
The rate of dermal absorption of benzene is generally lower than that for inhalation
exposure. Studies in animals suggest that 4 to 8 mg of benzene can be absorbed
through the skin (Ellenhorn and Barceloux, 1988). Following absorption, benzene is
widely distributed throughout the body. The relative rate of benzene uptake by
different organs is dependent on the perfusion rate of the tissues by blood. In
animals, maximum concentrations appear in tissues within three hours of exposure,
with the highest levels occurring in fat. Maximum benzene metabolite levels appear
in bone and fat (Ellenhorn and Barceloux, 1988).
Benzene undergoes metabolic transformation. Metabolism of benzene occurs
primarily in the liver, where it is converted to benzene oxide with subsequent phenol
formation. Other metabolites include catechol, hydroquinone, and conjugated
phenolic compounds. The primary oxidation of benzene is catalyzed by enzymes of
the cytrochrome oxidase system (ATSDR, 1987). Benzene is excreted unchanged via .
4-2
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the lungs and as metabolites in the urine. The major urinary metabolite is
unconjugated phenol.
QUALITATIVE ASSESSMENT OF TOXICITY
Acute exposure to benzene in humans causes central nervous system depression as
characterized by symptoms such as euphoria, headache, nausea, balance problems,
coma, and convulsions (Ellenhom and Barceloux, 1988). Persons exposed chronically
to benzene show evidence of hematotoxicity, immunotoxicity, and neurotoxicity.
Specifically, a decrease in the various cells of the blood (pancytopenia) is seen in
chronically exposed individuals due to a marked depression (hypoplasia) of the bone
marrow (ATSDR, 1987). Aplastic anemia is also characteristic of long-term benzene
exposure. The metabolite responsible for aplastic anemia is ·believed to be a
hydroquinone precursor. Epidemiological studies indicate an increased risk of acute
myelocytic and monocytic leukemia in benzene workers, with an overall five fold
greater risk for the development of leukemia (Ellenhom and Barceloux, 1988).
Because of the scarcity of data available on the relationship between exposure and
effect in human studies and the variety of conditions under which exposure occurs, it
· is difficult to determine, from the literature, the lowest dose at which adverse effects
can be observed in humans. Evidence suggests that benzene poisoning may occur at
levels as low as 10 ppm in the body.
Some hematotoxic effects observed in humans have been reproduced in animals.
Animal responses to benzene exposure vary and depend on factors such as species,
strain, duration of exposure, and whether exposure is intermittent or continuous
(ATSDR, 1987). The experimentally induced hematological effects of benzene appear
to be the same regardless of route of administration. It is believed that benzene
metabolites are the primary toxic agents in the induction of hematotoxicity and
4-3
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imrimnotoxicity. However, the neurological effects of benzene are thought to be
direct effects of benzene rather than its metabolites (ATSDR, 1987).
Benzene and its metabolites cause chromosome aberrations in humans, animals, and
cells in culture. In addition, benzene causes sister chromatid exchanges (SCE),
inhibition of DNA and RNA synthesis and DNA binding, as well as interference with
cell cycle progression in vivo in animals. Significant increases in SCEs were
produced in bone marrow cells of mice exposed to 28 ppm benzene for 4 hours.
Benzene has rarely been shown to cause gene mutations (ATSDR, 1987).
The only consistent evidence of reproductive toxicity of benzene is gonadal effects
noted in experimental animals. Specifically, histopathological changes, in the form of
bilateral cysts, were observed in ovaries and in testes. Atrophy, decrease in
spermatozoa, and a moderate increase in abnormal sperm formation were observed.
These mice were exposed to 300 ppm benzene vapor, 6 hours/day, 5 days/week for
13 weeks (ATSDR, 1987).
There is little information on the developmental toxicity of benzene in humans.
Benzene has been shown to be embryotoxic in animals, as evidenced by increased
incidences of resorptions, reduction in fetal weight, skeletal variations, and altered
hematopoiesis. It is important to note that benzene is not teratogenic or embryolethal
in test animals at levels causing toxicity to the mother, as indicated by a decrease in
maternal weight gain. Maternal toxicity is evident at levels of more than 100 ppm.
Sufficient evidence exists that benzene is not teratogenic and not overtly embryotoxic
at 10 ppm (ATSDR, 1987).
4-4
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QUANTITATIVE ASSESSMENT OF TOXICITY
The EPA classifies benzene as a Group A carcinogen with a cancer slope factor
(CSF) of 2.9 x 10·2 (mg/kg/d)"1 (EPA, 1992a) for both the oral and inhalation routes.
The studies that form the basis for the group A classification are several occupational
studies that demonstrate an increased incidence of nonlymphocytic leukemia in man
via inhalation, and increased incidence of neoplasia in rats and mice exposed by
inhalation and gavage (EPA, 1992a).
Recent studies have shown benzene to be leukemogenic in animals by inhalation.
Doubt about the results exists due to the difficulty of developing reliable animal
models for benzene-induced leukemia. Positive tests for cancer induction in animals
have also been shown via the oral routes of exposure, although the data were
inconclusive. However, dermal administration of benzene to animals resulted in no
evidence of skin tumors (ATSDR, 1987).
CRITERIA AND STANDARDS
• Cancer Slope Factor:
•
•
•
•
•
2.9 x 10·2 (mg/kg-day)"1, oral and inhalation (EPA, 1992a)
Drinking Water Health Advisory:
2.35 x 10·1 mg/I, ten-day -10 kg child (EPA, 1992a)
Ambient Water Quality Criteria:
6.6 x 10-1 µg/1, consumption of fish and water (EPA, 1992a)
4.0 x 10·1 µg/1, consumption of fish only (EPA, 1992a)
MCL: 0.005 mg/I, final (EPA, 1992a)
MCLG: 0, final (EPA, 1992a)
ACGIH TLV-TWA: 10 ppm (30 mg/m3) -A2 designation, suspect
human carcinogen (ACGIH, 1990)
4-5
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4.2 CHLOROFORM
Chloroform is a B2 carcinogen with adequate animal carcinogenicity data with
inadequate human data.
TOXICOKINETICS
Chloroform is rapidly and efficiently absorbed through the gastrointestinal and
respiratory tracts. Dermal absorption is significant only upon direct contact with
liquid chloroform. After absorption, chloroform is found in tissues with high lipid
contents. Chloroform readily crosses the blood-brain and placental barriers. It has
been detected in fetal liver and can be expected to be found in human milk.
Metabolism occurs by microsomal cytochrome P-450 oxidation to the ultimate end
products of carbon dioxide and hydrochloric acid. Carbon dioxide is excreted in
expired air while the hydrochloric acid metabolite is excreted via the urine.
Chloroform is excreted unchanged through the lungs, regardless of absorption route
(EPA, 1985).
QUALITATIVE ASSESSMENT OF TOXICITY
The primary effect from exposure to chloroform is central nervous system depression.
Humans exposed to chloroform reported such symptoms as dizziness, headaches,
giddiness, tiredness, and at high concentrations light intoxication. Additional
complaints included gastrointestinal distress and frequent urination. Chloroform used
as an anesthetic has been associated with depression of the central nervous system,
cardiac arrhythmias, hepatic necroses and fatty degeneration, polyuria, albuminuria,
and in cases of severe poisoning, renal tubular necrosis (EPA, 1985).
4-6
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The oral LD50 and inhalation LCw values for the rat are 908 mg/kg and
39,000 mg/m3 for 4 hours, respectively. Acute inhalation experiments produce mild
hepatic effects in mice. Subchronic inhalation experiments show mild hepatotoxicity
and nephrotoxicity in rats, which reversed when exposure was terminated. Similarly,
the primary effects of oral exposure were hepatic and renal damage (EPA, 1985).
Chloroform is classified as a probable human carcinogen, EPA Group B2 Carcinogen.
There is limited epidemiologic data supporting the association of increased risk of
bladder, colon, or rectal cancer with chloroform exposure in humans (EPA, 1985).
QUANTITATIVE ASSESSMENT OF TOXICITY
Chloroform is a confirmed animal carcinogen. Statistically significant increases of
tumors have been found following oral chloroform exposure for renal epithelial
tumors in rats, hepatocellular carcinomas in mice, kidney tumors in mice, and
hepatomas in mice. Chloroform also promotes growth and metastasis of murine
tumors. Animal studies show that the carcinogenicity of chloroform is organ specific,
affecting primarily the liver and kidney (EPA, 1985).
Evidence from studies measuring binding to macromolecules, DNA damage, and
mitotic arrest suggest that chloroform may be mutagenic. However, recent studies
have shown that chloroform may promote carcinogenesis rather than initiate it
(EPA, 1985).
Chloroform is considered to be highly fetotoxic, but not teratogenic. It has been
shown to cause adverse effects in pregnancy, delays in fetal development, and the
production of terata in experimental animals (EPA, 1985).
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CRITERIA AND STANDARDS
•
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4.3
Cancer Slope Factor:
6.1 x 10·3 (mg/kg/day)"1, oral (EPA, 1992a)
8.1 x 10·2 (mg/kg/day)"1, inhalation (EPA, 1992a)
Reference Dose: 1.0 x 10·2 mg/kg/day (EPA, 1992a)
Ambient Water Quality Criteria:
0.19 µg/1, consumption of fish and water (EPA, 1992a)
15.7 µg/1, consumption of fish only (EPA, 1992a)
MCL: 0.1 mg/I (total trihalomethanes), final (EPA, 1992a)
ACGIH TLV-TWA: 10 ppm (50 mg/m3) A2 designation -suspect
human carcinogen (ACGIH, 1990)
CHROMIUM
Both common forms of chromium are considered in this profile. Hexavalent
chromium is classified by the EPA as a Group A carcinogen, sufficient evidence of
carcinogenicity in humans by inhalation. Trivalent chromium is considered a
noncarcinogen.
Trivalent chromium forms a variety of stable complexes with organic and inorganic
compounds. Most trivalent chromium compounds (with the exception of some salts)
are insoluble in water. Chromium in biological systems is present in the trivalent
form and is also the most common form of chromium found in nature.
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TOXICOKINETICS
Hexavalent Chromium
Gastrointestinal absorption of ingested hexavalent chromium has been estimated to be
approximately 2 percent in humans. Comparable levels have been observed in
experimental animals, while high absorption levels, 25-50 percent, have been
observed in animals administered hexavalent chromium directly into the GI tract.
Animal studies have also indicated rapid absorption of water-soluble hexavalent
chromium compounds following inhalation exposure. The acid environment of the
stomach reduces much of the ingested hexavalent chromium to its trivalent form.
Absorbed chromium can be distributed throughout the body and temporarily stored in
a variety of soft tissues. Hexavalent chromium is generally more rapidly and
extensively taken up by both exposed organisms and specific cell types. Once
absorbed, hexavalent chromium is likely to be transformed into the trivalent state,
which readily forms complexes with biological constituents. Urine is the primary
route of excretion. The lungs are the only tissue which appear to accumulate
chromium with age. Inhalation exposure seems to be the primary route of exposure
to this compound (EPA, 1984).
Trivalent Chromium
Gastrointestinal absorption of ingested trivalent chromium has been estimated to be
approximately 0.4 percent in humans. Comparable levels have been observed in
experimental animals. The acid pH of the stomach tends to keep chromium in the
trivalent form. Absorption of chromium following inhalation exposure is low, more
likely due to the formation of insoluble complexes with macromolecules. Chromium
can be distributed throughout the body and temporarily stored in a variety of soft
tissues, with the liver and spleen being the major sites of accumulation and clearance.
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Inhalation, not oral, exposure appears to be the primary route of exposure. Urine is
the major route of excretion (EPA, 1984).
QUALITATIVE ASSESSMENT OF TOXICITY
Hexavalent Chromium
Chromium, at levels below those associated with adverse effects, is an essential
element in human nutrition. The daily requirement for chromium has been estimated
to be approximately 50 µg/day. Inhalation exposures to chromium compounds have
been associated with nasal damage, such as perforated septum, nosebleeds, and
inflamed mucosa. Skin contact with high levels of chromium compounds has been
reported to produce an eczema-like condition.
Experimental studies of oral exposure to hexavalent chromium have not conclusively
demonstrated any adverse effects by this route. However, large doses have been
associated with kidney damage (EPA, 1984a).
The primary toxic effect of concern for hexavalent chromium is respiratory cancer
following inhalation exposures. Numerous studies of occupational inhalation
exposures in the chromate, chrome-plating, and chrome pigment industries have found
increased incidence of respiratory cancers in groups exposed to chromium compounds
(EPA, 1984a).
Respiratory cancer has not been observed in experimental animals exposed to
chromium via inhalation. However, several chromium compounds have been shown
to be carcinogenic in various bioassay studies (EPA, 1984a).
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Hexavalent chromium is suspected of being responsible for mutagenic and cell
transforming effects of chromates in various test systems. These adverse effects
appear to be prevented in the presence of liver enzymes or gastric juice, but are
unaffected by lung enzymes (EPA, 1984a).
There is inconclusive evidence on the reproductive and developmental effects of
chromium in experimental animals (EPA, 1984a).
Trivalent Chromium
Most toxic effects associated with chromium compounds are attributed to the more
highly soluble, irritating hexavalent form. Trivalent chromium is considered one of
the least toxic of the trace metals. The few available experimental studies of
ingestion and. inhalation exposures using a variety of animal species have shown no
adverse effects specifically attributable to trivalent chromium (EPA, 1984).
Although occupational exposure to chromium compounds has been associated with
increases in respiratory cancer, it is thought that this effect is primarily due to
hexavalent chromium. This theory is supported by animal bioassays involving
exposures to trivalent chromium compounds. There has been no evidence of
carcinogenicity from exposure to trivalent chromium compounds (EPA, 1984).
Trivalent chromium has produced either negative or weak mutagenic activity in a
variety of assays. Similarly, evidence of its ability to produce chromosomal damage
has been conflicting (EPA, 1984). No information is available on the potential
reproductive and developmental effects of trivalent chromium by either inhalation or
ingestion exposure (EPA, 1984).
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QUANTITATIVE ASSESSMENT OF TOXICITY
Hexavalent Chromium
No adverse effects were observed in rats provided with drinking water containing
potassium chromate at a concentration of 25 mg/I of hexavalent chromium,
corresponding to a dose of 2.4 mg/kg-day, for one year (MacKenzie, et. al., 1958).
An uncertainty factor of 500 represents two 10-fold factors to account for the
expected interhuman and interspecies variability, and an additional factor of 5 to
compensate for the less-than-lifetime exposure duration of the study. The RID is
limited to soluble salts of hexavalent chromium (EPA, 1992a).
Hevalent chromium is classified as a Group A human carcinogen by inhalation based
on sufficient evidence of human carcinogenicity. Results of epidemiologic studies are
consistent across investigators and locations. Studies of chromate production facilities
in the U.S., Great Britain, Japan, and West Germany have established an association
between chromium exposure and lung cancer. Three studies of the chrome pigment
industry in Norway, England, and the Netherlands found an association between
occupational chromium exposure and lung cancer (EPA, 1992a).
The CSF is based on an observed increase in lung cancer risk to chromate production
plant workers. A cohort of workers who had worked at least 1 year between 1931
and 1937 was studied. The rate of deaths due to lung cancer among chromate
workers (18.2 percent) was significantly different from deaths to lung cancer among
males in the county where the plant was located (1.2 percent) (EPA, 1992a).
Workers were exposed to a range of concentrations from < 1 mg/m3/year to 7.99
mg/m3/year of insoluble (trivalent chromium) and soluble (hexavalent chromium)
chromium compounds. Lung cancer mortality was dose-related to total chromium
exposure in this study (ATSDR, 1989).
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A more recent study of chromium pigment workers in New Jersey found a statistically
significant association between the total number of years of employment in the factory
and total number of years of exposure to chromate dust, with an excess risk of lung
cancer. Excess risk for duration of exposure was only significant for subjects
followed 30 years or more after initial employment (implying a long latency period)
(Hayes, 1989).
CRITERIA AND STANDARDS
• Cancer Slope Factor (CSP):
4.1 x 101 (mg/kg-day)"1, inhalation (EPA, 1992a)
• Reference Dose (RID): 5 x 10·3 mg/kg-day, oral (EPA, 1992a)
•
•
•
•
•
Drinking Water Health Advisory:
1.4 mg/1 ten day -10 kg child (EPA, 1992a)
0.24 mg/1 long term -10 kg child (EPA, 1992a)
0.84 mg/1 long term -70 kg adult (EPA, 1992a)
MCL: 0.05 mg/1 (total chromium) (EPA, 1992a)
0.1 mg/1 effective date December 1992
MCLG: 0.1 mg/I (EPA, 1992a)
Ambient Water Quality Criteria:
0.05 mg/1, consumption of fish and water, (EPA, 1992a)
ACGIH TLV-TWA: 0.05 mg/m3 (ACGIH, 1990)
Trivalent Chromium
The oral RID is based on a chromium feeding study with rats (Ivankovic &
Preussmar; 1975). Groups of 60 male and female rats were fed chromic oxide
(Cr20 3) at doses of 360, 720, and 1,800 g/kg body weight. No effects were observed
at any dose level, therefore the No Observed Effect Level (NOEL) is 1,800 g/kg
body weight (converted by percentage of chromium in chromic oxide and number of
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feeding days). An uncertainty factor of 1()() accounts for the expected interhuman and
interspecies variability to the toxicity of the chemical. An additional modifying factor
of 10 reflects uncertainty due to the following factors: l) a 90-day study (reported in
the same article) found effects including reduction of liver and spleen weights,
therefore, the NOEL may also be a Lowest Observed Adverse Effect Level
(LOAEL); 2) chromium absorption is low ( < 1 percent), thus, a considerable potential
variation in absorption exists; and, 3) animals were allowed to die naturally after
feeding stopped (two years), and only then was the histology performed
(EPA, 1992a).
CRITERIA AND STANDARDS
•
•
•
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•
4.4
Reference Dose (RID):
l mg/kg-day, oral as insoluble salt (EPA, 1992a)
Drinking Water Health Advisory:
1.4 mg/I ten day -10 kg child (EPA, 1992a)
0.24 mg/I long term -10 kg child (EPA, 1992a)
0.84 mg/I long term -70 kg adult (EPA, 1992a)
MCL: 0.05 mg/I (total chromium) (EPA, 1992a)
0.1 mg/I effective date December 1992
MCLG: 0.1 mg/I (EPA, (1992a)
Ambient Water Quality Criteria:
170 mg/I, consumption of fish and water (EPA, 1992a)
3,433 mg/I, consumption of fish only (EPA, 1992a)
ACGIH TLV-TWA: 0.5 mg/m3 (ACGIH, 1990)
1,2-DICHLOROETHANE
1,2-Dichloroethane is classified as a B2 human carcinogen. The animal data is
sufficient to indicate carcinogenicity while there is no adequate human data available.
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TOXICOKINETICS
1,2-Dichloroethane is readily absorbed through the lungs following inhalation
exposure in both humans and experimental animals. This is expected based on its
high vapor pressure. Absorption is most likely to occur via passive diffusion across
alveolar membranes. The rapid absorption of 1,2-dichloroethane following inhalation
exposure has been demonstrated in experimental animals. A study exposing rats
showed peak blood levels to be constant at 2 to 3 hours after the onset of a 6 hour
inhalation exposure to 150 ppm of 1,2-dichloroethane (ATSDR, 1989a). No studies
were located regarding absorption in humans following oral exposure. However, it
can be inferred from case studies that toxic effects are observed subsequent to
accidental or intentional ingestion of 1,2-dichloroethane by humans.
1,2-Dichloroethane is rapidly absorbed to the systemic circulation following exposure
by the oral route. Studies in experimental animals indicate that oral absorption of
1,2-dichloroethane is rapid and complete (ATSDSR, 1989a). Skin absorption via
contact with contaminated water or the chemical itself may be a significant route of
exposure to 1,2-dichloroethane in humans, however it has not been validated in
scientific studies. Results from animal studies indicate that dermal absorption of
1,2-dichloroethane is low in comparison to absorption reported for other compounds
(ATSDR, 1989a).
No studies were located regarding the distribution of 1,2-dichloroethane in humans
following inhalation, oral, and dermal exposure. However, 1,2-dichloroethane is
believed to be rapidly distributed. in humans following inhalation exposure. Animal
study results reported the distribution of 1,2-dichloroethane in rats following daily
oral administration. The study demonstrated that there was no difference between
blood or tissue levels following either single or repeated exposure. These results
indicate that bioaccumulation of 1,2-dichloroethane does not occur with repeated oral
exposure. No studies were located regarding distribution in animals following dermal
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exposure. Since the tissue distribution of this chemical did not appear to be route-
dependent following either inhalation or oral exposure, and since it is well absorbed
through the skin, the distribution pattern of 1,2-dichloroethane following percutaneous
application may possibly resemble that observed by other routes of exposure.
Metabolism of 1,2-dichloroethane after oral exposure is dose-dependent .
no studies were located regarding metabolism on humans following inhalation, oral or
dermal exposure to 1,2-dichloroethane.
Limited information is available regarding excretion in humans following oral,
inhalation and dermal exposure to 1,2-dichloroethane. It appears that
1,2-dichloroethane is eliminated rapidly in the breath unchanged.
Animal studies provide evidence that elimination of 1,2-dichloroethane is rapid
following either inhalation or oral exposure and that it occurs primarily via urinary
excretion or by exhalation (ATSDR, 1989a).
QUALITATIVE ASSESSMENT OF TOXICITY
The primary route of human exposure to 1,2-dichoroethane is expected to be
inhalation of vapors in ambient air in the workplace or in areas surrounding hazardous
wastes. Both human and animal data indicate that 1,2-dichloroethane is a concern for
those individuals living or working in areas where this compound is present.
No studies were located regarding immunological, developmental, reproductive, or
genotoxic effects in humans following inhalation exposure to 1,2-dichloroethane.
Most of the information available consists of case reports of accidental or
occupational exposure to 1,2-dichloroethane vapor. These studies are difficult to
interpret because exposure concentration was usually not quantified, and dermal
exposure to 1,2-dichloroethane was likely to occur concurrently with inhalation
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exposure. Information concerning the systemic effects of inhaled 1,2-dichloroethane
in humans is limited ·to case study reports. The human health effects associated with
ingested 1,2-dichloroethane was also likely to occur concurrently with inhalation.
Acute animal inhalation studies exposing various animal species to 1,2-dichloroethane
at high concentrations, caused death in a number of animal species. The data is
limited in usefulness due to the small number of animals used in these studies.
1,2-Dichloroethane was found to be mutagenic in Salmonella where excessive
evaporation was prevented in the assay (EPA, 1992a).
QUANTITATIVE ASSESSMENT OF TOXICITY
1,2-Dichloroethane was administered by gavage to groups of male and female rats and
mice. Treatment was for 78 weeks followed by an observation period of 12 to 13
weeks for mice and 32 weeks for rats. Dosages were 47 and 95 mg/kg/day for rats,
and 97 and 195 mg/kg/day for male mice and 149 and 299 mg/kg/day for female
mice. All high-dose male rats died after 23 weeks of observation, the last high-dose
female died after 15 weeks. Male rats had significantly increased incidence of
forestomach squamous-cell carcinomas and circulatory system hemangiosarcomas.
Female rats and mice were observed to have significant increases in mammary
adenocarcinoma incidence. Mice of both sexes developed alveolar/bronchiolar
adenomas, females developed endometrial stromal polyps and sarcomas, and males
developed hepatocellular carcinomas (EPA, 1992a).
Inhalation exposure of rats and mice did not result in increased tumor incidence. An
elevation in lung adenomas that was not statistically significant was seen in mice
treated by the intraperitoneal route with 1,2-dichloroethane in tricaprylin. Another
strain of mice treated topically had a significant increase in benign lung papillomas,
but not skin carcinomas (EPA, 1992a).
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Adequate numbers of animals were treated and observed for the majority of their
expected lifespan following oral exposure. The incidence of hemangiosarcoma was
significantly elevated in the treated animals and was dose-related. A slope factor
could be calculated based on data from hepatocellular carcinomas in male mice. The
inhalation risk estimate was derived from the oral data as the inhalation studies did
not result in increased tumor incidence.
CRITERIA AND STANDARDS
4.5
• Cancer Slope Factor (CSP):
•
•
•
•
•
9 x 10-2 mg/kg-day-1, oral and inhalation (EPA, 1992a)
Drinking Water Health Advisory:
0.74 mg/I ten-day -10 kg child (EPA, 1992a)
0.74·mg/1 long-term -10 kg child (EPA, 1992a)
2.6 mg/I long-term -.70 kg adult (EPA, 1992a)
MCL: 0.005 mg/I (EPA, 1992a)
MCLG: 0 (EPA, 1992a)
Ambient Water Quality Criteria:
9.4 x 10-1 µg/1, consumption of fish and water (EPA, 1992a)
2.4 x 10+2 µg/1, consumption of fish only (EPA, 1992a)
ACGIH TLV-TWA: 10 ppm (40 mg/m3) (ACGIH, 1990)
ETHYLBENZENE
The EPA classifies ethylbenzene as a Group D carcinogen, not classifiable as to
human carcinogenicity due to inadequate or lack of animal bioassays and human
studies.
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TOXICOKINETICS
There is no information regarding the absorption of ethylbenzene through the
gastrointestinal tract. Ethylbenzene is absorbed through inhalation and dermal
contact. It appears to be distributed throughout the body in various tissues. In
experimental animals, highest levels were detected in the kidney, lung, adipose tissue,
digestive tract, and liver. In humans, this compound is rapidly metabolized to form
primarily, mandelic acid and phenylglyoxylic acid. These two metabolites account for
64 percent and 25 percent of the absorbed dose. In humans, most of the inhaled dose
is eliminated in the urine within 24 hours after termination of exposure (EPA, 1987).
QUALITATIVE ASSESSMENT OF TOXICITY
Ethylbenzene is characterized as being an irritant to the skin. This compound is
slightly irritating to the mucous membranes. No systemic effects can be expected at
levels producing skin and eye irritation. The acute toxicity of ethylbenzene is
considered to be low. In human volunteers, an eight hour inhalation exposure to 100
ppm of ethylbenzene produced no adverse effects. This level was increased to an
unspecified level. Effects observed included sleepiness, fatigue, headache, and mild
eye and respiratory tract irritation (EPA, 1987).
In guinea pigs, 10,000 ppm, has been shown to be fatal within a matter of minutes.
Death was preceded by vertigo, unsteadiness, and ataxia. The animals that died from
this exposure were found to have intense congestion and edema of the lungs and
generalized visceral hyperemia. A chronic inhalation study produced no effects in
several animal species tested, except in livers for those animals dosed with 400 ppm
of ethylbenzene for six months. Acute effects reported in animals include eye
irritation and central nervous system depression. Liver and kidney effects were
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observed in rats receiving 408 to 680 mg/kg/day of ethylbenzene for six months
(EPA, 1987).
Ethylbenzene was not mutagenic in Salmonella typhimurium or Saccharomyces
cerevisiae test strains, with and without metabolic activation. At the highest dose
tested, ethylbenzene had a minimal effect on induction of sister chromatid exchange
after a 48-hour treatment of whole blood lymphocytes in vitro. Ethylbenzene did not
elicit a positive mutagenic response in Drosophila, yeast cells, or rat liver epithelial
cells (EPA, 1987).
No studies on the reproductive effects of ethylbenzene were located in the available
literature. No embryotoxic, fetotoxic, or teratogenic effects were observed in rats or
rabbits inhaling up to 1,000 ppm of 6 to 7 hours/day on days 1 to 19 and 1 to 24 of
gestation, respectively. Female rats exposed to 1,000 ppm had an increase in liver,
kidney, and spleen weights which suggested maternal toxicity. However, at 100 ppm
no maternal effects were reported (EPA, 1987).
QUANTITATIVE ASSESSMENT OF TOXICITY
There are no animal or human carcinogenicity studies available which places
ethylbenzene in Group D, not classifiable as to human carcinogenicity. The National
Toxicology Program (NTP) has plans to conduct metabolism and excretion bioassays
in animals (EPA, 1992a).
Ethylbenzene is a noncarcinogen based on a long term rat study. Female rats were
given ethylbenzene for 5 days/week at doses of 13.6, 136, 408, or 680 mg/kg/day in
olive oil by gavage. Parameters measured were growth, mortality, appearance,
behavior, hematalogic changes, blood urea nitrogen concentrations, and organ and
body weights. Histopathological changes were observed in the liver and kidney at
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the LOAEL (lowest observed adverse effect level) of 408 mg/kg/day. Drawbacks to
this study were that only female rats were tested and the experiment was not a chronic
study. Other oral toxicity data was not found (EPA, 1992a). The inhalation
reference concentration is based on an inhalation study exposing rats and rabbits to 0,
100, or 1,000 ppm ethylbenzene for 6 to 7 hours/day for 7 days/week during
gestation. The NOAEL (no observed adverse effect level) was 100 ppm or 434
mg/m3 (EPA, 1992a). The reference concentration (RfC) of I x 10° mg/m3 included
an uncertainty factor to protect sensitive individuals, an adjustment for interspecies
conversion, and an adjustment for the absence of multigenerational reproductive and
chronic studies. The inhalation RID is derived by applying the standard inhalation
rate (20 m3/day) and body weight (70 kg) to obtain the correct units. The RID for the
inhalation route is 3 x 10·1 mg/kg/day.
CRITERIA AND STANDARDS
•
•
•
•
•
•
Reference Dose:
(RID) 1 x 10·1 mg/kg/day, oral (EPA, 1992a)
(RfC) 1 x 10° mg/m3, inhalation (EPA, 1992a)
Drinking Water Health Advisory:
32 mg/I one day -10 Kg child (EPA, 1992a)
3.2 mg/I ten day -10 Kg child (EPA, 1992a)
1 mg/I long term -10 Kg child (EPA, 1992a)
3.4 mg/1, long term -70 Kg adult (EPA, 1992a)
0.68 mg/I lifetime (EPA, 1992a)
MCL: 0.7 mg/I final (EPA, 1992a)
MCLG: 0.7 mg/1 final (EPA, 1992a)
SMCL: 0.03 mg/I proposed (EPA, 1992a)
Ambient Water Quality Criteria:
1.4 mg/I, consumption of fish and water (EPA, 1992a)
3.28 mg/I, consumption of fish only (EPA, 1992a)
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• ACGIH TLV~TWA: 100 ppm (434 mg/m3) (ACGIH, 1990)
4.6 LEAD
Lead is classified as a B2 carcinogen. This would indicate sufficient evidence of
carcinqgenicity in animals with adequate or lack of evidence in humans.
TOXICOKINETICS
Approximately 8 percent of the lead ingested by human adults is thought to be
absorbed. Rates in children are higher, for example, lead in foods is thought to be
absorbed by 45 -50 percent. This absorption level is generally higher in animals or
humans that have been fasting. The absorption rate for human infants is
approximately 50 percent. Lead is also absorbed after inhalation, with the pulmonary
deposition rate range from 30 to 50 percent (ATSDR, 1988).
After being absorbed, most inorganic lead compounds dissociate, yielding lead.
Tetramethyl and tetraethyl leads are dealkylated to tri-and di-alkyl compounds which
are more toxic. In adults, under conditions of long-term exposure, approximately
95 percent of the total amount of lead found in the body is localized in the skeleton.
In the blood, most lead is found in the erythrocytes. Lead also readily crosses the
placenta. In most species, the main route of excretion is through the bile. However,
in baboons and humans, urine appears to be the primary route (Casarett and Doull,
1986).
QUALITATIVE ASSESSMENT OF TOXICITY
At high exposure levels, lead produces encephalopathy, gastrointestinal effects,
anemia, nephropathy, and electrocardiographic abnormalities. These effects are
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primarily seen in children or from occupational exposure. Lower level exposure to
lead in all humans can affect the synthesis of heme, which in tum affects metabolic
processes and decreases vitamin D circulating in the body which reduces calcium
stability in the body.
Effects of great concern from low level lead exposure are neurobehavioral effects and
growth retardation in infants exposed prenatally and children exposed postnatally.
Inhalation of airborne lead is generally a minor exposure pathway for children, but
lead containing particles can be responsible for high concentrations of lead in dust that
children ingest. Increased blood pressure from low level lead exposure in middle
aged men has also been observed. Based on blood lead concentrations, no clear
threshold of effect has been shown from low level lead exposures resulting in blood
lead levels < 10 µg/dl (ATSDR, 1988).
In experimental animals, effects associated with exposure to lead and lead compounds
are similar to those in humans. Observed effects have included weight loss,
decreased survival, and neurological, cardiovascular, and kidney effects. Several
studies with experimental animals suggest that lead may interfere with immune
response (Clement, 1985).
Data concerning the carcinogenicity of lead in humans are inconclusive. There is no
evidence that oral exposure produces a tumor response. Although studies of
occupational inhalation exposure have produced negative results, increases in cancer
of the digestive organs and respiratory system have been reported (EPA, 1992a).
There is evidence in experimental animals that lead salts are carcinogenic in both
mice and rats, resulting in tumors of the kidneys after either oral or parenteral
administration. Most of the investigations found a carcinogenic response only at the
highest dose. Metallic lead, lead oxide and lead tetralkyls have not been tested
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adequately. No studies are available on the carcinogenic potential of lead compounds
via inhalation (EPA, 1992a).
Lead has been shown, in a number of DNA structure and function assays, to affect
the molecular processes associated with the regulation of gene expression. Lead
acetate includes cell transformation in Syrian hamster embryo cells and enhances the
incidence of simian adenovirus induction. Lead oxide shows a similar enhanced
adenovirus induction. Under certain conditions, lead compounds may induce
chromosomal aberrations in vitro and in tissue cultures. One study showed a
relationship between sister chromatid exchange and lead exposure in exposed workers
(EPA, 1992a).
In experimental animals, various non-teratogenic reproductive effects have been
observed including developmental delays, decreased fertility, and fetotoxicity. No
reproductive effects from human oral exposure to lead have been reported; however,
occupational inhalation exposures have been linked to altered testicular function,
increases in spontaneous abortion, premature delivery, and early membrane rupture
(Clement, 1985).
QUANTITATIVE ASSESSMENT OF TOXICITY
The classification of lead as B2, probable human carcinogen, is based on sufficient
animal data and insufficient human data. Ten rat bioassays and one mouse assay
showed statistically significant increases in renal tumors with dietary and
subcutaneous exposure to several soluble lead salts. The most characteristic cancer
response is bilateral renal carcinoma, however, there is some evidence of multiple
tumor sites (EPA, 1992a).
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Cancer risk due to exposure to. lead involves many uncertainties, such as age, health,
nutritional state, body burden and exposure duration which influence the absorption,
release and excretion of lead. In addition, current knowledge of lead
pharmacokinetics indicates that an estimate derived by standard procedures would not
truly describe the potential risk, therefore, the EPA does not currently recommend a
specific cancer slope factor (EPA, 1992a).
The maximum contaminant level goal (MCLG) in drinking water is zero. This value
is based on: (!) the EPA's goal to reduce total lead exposures, (2) the classification
of lead as a B2 carcinogen, and (3) occurrence of low level effects and difficulties in
identifying clear threshold levels. There is no maximum contaminant level (MCL).
The EPA recognized that a MCL of zero is not feasible and recommends a treatment
approach which will achieve public health goals (EPA, 1992a). The treatment
technique action level is 0.015 mg/I (EPA, 1991a).
CRITERIA AND STANDARDS
•
•
•
•
•
•
Cancer Slope Factor (CSF): None established due to uncertainty and
probable health effects at low levels
Reference Dose (RID): No threshold level established. Very low
levels are known to cause adverse health effects, especially in children.
MCL: 0 (EPA, 1992a)
MCL: 0.015 mg/I at the tap (EPA, 1991a)
Ambient Water Quality Criteria:
50 µg/1, consumption of fish and water (EPA, 1992a)
ACGIH TLV-TWA:
0.15 mg/m3, inorganic dust and fumes, as Pb (ACGIH, 1990)
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5.0 RISK CHARACTERIZATION
5.1 CURRENT LAND-USE CONDffiONS
The risk characterization addresses potential future risks and hazards to human health
posed ·by current site conditions. Soil removal at the site had eliminated the potential
for significant exposure to trespassers on the site. In addition, no wells which use the
shallow aquifer in the vicinity of the site are currently contaminated with chemicals
from the site. It appears, therefore, that there are no complete pathways for current
exposures.
The risk characterization is based on the identified chemicals of concern and
residential use of groundwater. Exposure to soil, surface water, and air is not
considered for these receptors as discussed in Section 3.2.
Daily intake, based upon the upper 95 percent confidence limit concentration in
groundwater, is multiplied by the cancer slope factor (CSF) or divided by the
reference dose (RID) for each chemical of concern. Cancer slope factors, EPA
weight of evidence, and the reference doses for noncarcinogens are presented in
Table 5-1. In cases where more than one potential carcinogen is present, risks
associated with the individual contaminants were added to determine the total cancer
risk as recommended by the EPA. According to EPA guidance for Superfund sites,
the total carcinogenic risk should be within the range of lxlo-4 to lxlO.;;. The hazard
quotient for each noncarcinogen is summed to yield the hazard index (HI). A HI of
less than one would indicate that adverse effects are not likely to occur following
exposure to the noncarcinogenic chemicals onsite.
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Benzene
Chloroform
Chromium ( +6)
TABLE 5-1
SLOPE FACTORS and RIDs USED TO ESTIMATE
CARCINOGENIC AND NON-CARCINOGENIC RISK
NEW HANOVER COUNTY AIRPORT SITE
WILMINGTON, NORTH CAROLINA
A 2.9 X 10-2<1> 2.9 X 10-2<1>
B2 6.1 X 10-3(2) 8.1 X 10-2(2>
A NIA 4.1 X lQ+l(I)
1,2-Dichloroethane B2 9.1 X 10-2<1> 9 .1 X 10-2(1)
Eth y !benzene D
Lead B2 * *
NOTES:
• Inhalation reference dose.
5 X 10-3(I)
1 X 10-l(I)
(3 X 10-l)'(I)
* A quantitative assessment for lead cannot be performed as EPA has withdrawn its
toxicity criteria.
NI A Not available. There is inadequate evidence for carcinogenicity of hexavalent
chromium by the oral route.
c1> EPA, 1992a. IRIS database.
(2> EPA, 1991b. HEAST.
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The carcinogenic risk (presented in Table 5-2) to the residential adult following
consumption of contaminated groundwater is estimated to be 5xl0-5• The
carcinogenic risk associated with the inhalation of vapors during a shower is 5xl0-5•
Nearly 74 percent of total carcinogenic risk is due to ingestion of benzene.
1,2-Dichloroethane contributes the rest (approximately 11 percent), with chloroform
contributing only about 15 percent. The noncarcinogenic hazard index is less than 1
(0.5), suggesting that non-cancer effects from oral and inhalation exposure to these
chemicals are not expected.
5.2 UNCERTAINTIES
The risk assessment is aimed at providing a conservative estimate of risk for the site.
A number of uncertainties and assumptions made throughout the risk assessment are
likely to overestimate rather than underestimate risk. For example, it is a
conservative assumption to consider groundwater as the primary exposure pathway
even though benzene, a carcinogen, was not detected in the closest downgradient
private well. However, the potential exists for future migration of contaminants.
Soil samples collected in the first and third rounds may not necessarily be
representative of the site in its present condition and this introduces some uncertainty
into the risk assessment. It is likely that all contaminated soils were removed in the
PRP remediation and that surficial soil may not pose a risk, however, since there is a
lack of surficial soil data this could not be verified. Surficial soil samples should be
collected at a later date to provide assurance that remaining soil will not pose a
human health risk, however this will be discussed in the feasibility study for
remediation of the site.
The exposure scenario also involves a number of uncertainties. Consumption of 2
liters of contaminated drinking water per day for 350 days a year represents the upper
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Benzene
Chloroform
Chromium ( +6)
1,2-Dichloroethane
Ethylbenzene
Lead
TABLE 5-2
HUMAN HEALTH RISK
NEW HANOVER COUNTY AIRPORT SITE
WILMINGTON, NORTH CAROLINA
3.7x10-s 3.7x 10-s
7.9 X IQ-7 1.0 X 10-s
7.5 X 10~ 7.5 X 10~
•
0.45
0.006
(0.002)'
Total 5 X 10-s 5 X 10-5 0.5
TOTAL RISK TOTAL HAZARD < 1
NOTES:
•
•
CSF
RID
Inhalation hazard index .
Indicates that a risk value could not be calculated. Chromium does not have an
oral CSF.
Metals are not likely to volatilize from groundwater due to their physical/chemical
properties.
Cancer slope factor.
Reference dose.
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bound of potential exposure and has been used because site-specific data are not
available. This may be an over estimation of the actual exposure that may occur in
the future. The scenario assumes that an adult is consistently being exposed to the
same concentration for 30 years. The daily intake by inhalation is reported as being
equal to the daily intake by ingestion. The use of this assumption yields an almost
equal risk for the inhalation scenario. The estimated risk for residential groundwater
consumption is in the acceptable risk range. Dermal absorption of vapor phase
chemicals is considered to be lower than inhalation intakes in many instances (EPA,
1989), and is not considered in this risk assessment.
Compounds presumed to be detected in a sample, qualified as "JN," were not
considered in the risk assessment. Those compounds could not be evaluated
quantitatively. The qualitative assessment of tentatively identified compounds (TICs)
is uncertain since both the identification and concentration of those chemicals are
questionable and toxicity data is limited. The risk assessment focuses on
contaminants with known toxicity that exceed state or federal criteria, such as
benzene. Several TICs are found in groundwater samples that contain benzene. It is
assumed that benzene exhibits the greater toxicity.
Chromium and ethylbenzene were assessed for non-cancer health effects. Other
chemicals may contribute to non-cancer effects and this may lead to an
underestimation of risks. There is a RID for chloroform, however, this chemical is
evaluated based on its potential for carcinogenic effects. The hazard quotient for this
chemical does not contribute significantly to the noncarcinogenic hazard index as it is
expected to be in the range of 0.01.
For the organic chemicals, RfDs are not available. All are, however, expected to be
more hazardous as carcinogens than as systemic toxicants. Groundwater
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concentrations which are protective for cancer risks, therefore, should also protect for
non-cancer effects.
There is a great deal of uncertainty is assessing the toxicity of a mixture of chemicals.
The chemicals of concern are present in groundwater along with other contaminants
and TICs, and an individual will be exposed to this mixture of compounds. This risk
assessment focuses on the total potential risk from exposure to carcinogenic chemicals
of concern. It is necessary to understand the mechanism of action to determine how
these contaminants will interact. An interaction may occur during absorption,
distribution, metabolism, excretion or at the receptor site. The mixture may be
metabolized to yield a component of greater or lesser toxicity. Little data is available
to accurately characterize the effects of chemical mixtures. Risk values are summed ·
for each pathway and then added to yield the total site risk. This approach is
recommended by the EPA.
In addition, uncertainty occurs in the derivation of the CSP for a carcinogen which is
derived from animal and epidemiology studies. There are uncertainties in
extrapolating both from animals to humans and from high to low doses. There are
species differences in uptake, metabolism, and organ distribution of carcinogens, as
well as species and strain differences in target site susceptibility. Human populations
are also variable with respect to their genetic composition, diet, occupational and
home environments, and activities. The CSP is based on the upper bound estimate of
these studies and true risk is not likely to exceed the upper bound estimate and in fact
may be lower.
As a result of these uncertainties and assumptions described above, the risk
assessment is a conservative analysis intended to indicate the potential for adverse
impacts to occur and not an absolute estimate of risk to humans or a specific
population. The exposure evaluated assumes daily ingestion of contaminated drinking
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I water at the same concentration for 30 years. Inhalation of these vapors is also
considered to occur at the same concentration for 30 years. This exposure is expected
I to be greater than what is likely to occur in the future.
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6.0 ENVIRONMENTAL ASSESSMENT
An endangered species survey was performed in April 1991, by CDM Federal
Programs Corporation for Region IV EPA. The survey was a subtask of the RI/FS
for the New Hanover Site. The objective of the survey was to identify those species
which may be adversely impacted as a result of their proximity to the site and
exposure to site related contaminants.
6.1 SCOPE OF THE INVESTIGATION
Prior to conducting the endangered species survey, relevant federal, state, and local
regulatory agencies were contacted. Historical information was obtained from the
following organizations regarding the flora and fauna on the site:
• North Carolina Wildlife Resources Commission.
• North Carolina Department of Agriculture.
• North Carolina Natural Heritage Program.
• New Hanover County officials.
This information is presented in Appendix B.
Special attention was given to endangered species, as identified by the State of North
Carolina and/or the U.S. Fish and Wildlife Service list of threatened, endangered, or
candidate species for the state or federal endangered species list (North Carolina
General Statutes 113-337; 50 CPR Subpart 17: 11 and 17: 12).
Informal communications were also conducted with site investigation workers and
visitors. Previous site visitors identified amphibia (frogs) reported to be unique to the
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site in the area of the bum pit. However, no other significant species sightings had
been reported previously for this site (CDM, 1991):
The endangered species survey was performed on April 15-16, 1991. The
observations were conducted for a 14-hour time period, 5:00 am to 7:00 pm. The
purpose of this schedule was to encompass both nocturnal and diurnal fauna foraging.
Floral ·observations were conducted during the mid-morning and mid-afternoon to
maximize observation time .
6.2 SITE DESCRIPTION AND STUDY AREA
In general, the site setting consists of a disturbed semi0revegetated field covered by
grasses, scrubs and opportunistic herbs. At the time of the survey, exposed soil
dominated the immediate bum pit area. The area adjacent to the site is densely
vegetated with a typical southern pine/mixed hardwood forest. A recent site visit by
CDM personnel in January of 1992 showed that the exposed soil areas were slowly
becoming revegetated with grasses.
6.3 RESULTS OF SURVEY
Grasses are the dominant vegetation at the site, interspersed with wild strawberries,
hay-scented fem, and poison ivy. The forested area immediately adjacent to the site,
also know as the ecotone, is dominated by scrubs, which include magnolia, poison
sumac, southern bayberry, and red maple. Table 6-1 presents the identified flora.
The adjacent forested habitat is typical of a coastal plain mixed southern hardwood
forest. The sandy soils are covered by decomposing leaf litter. The canopy is
predominantly closed and consists of longleaf pine, elm, sweet gum, and shortleaf
pine. The understudy includes red maple, flowering dogwood, sassafras, southern
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TABLE 6-1
IDENTIFIED FLORA
NEW HANOVER COUNTY AIRPORT SITE
WILMINGTON, NORTH CAROLINA
American Elm
Arrowleaf
Bamboo
Blackberry .
Carolina Basswood
Cinnamon Fem
Dogwood
Felter Bush
Fem
Fly Poison
Hay-scented Fem
Honeysuckle
Marsh Pennywort
Pink Spiderwort
Plantain
Poison Ivy
Poison Sumac
Post Oak
Red Chokeberry
Red Maple
Sand Myrtle
Sassafras
Shortleaf Pine
Slash Pine
Southern Bayberry (Wax Myrtle)
Ulmus americana
Peltrandra virginica
Barnbosa vulgaris
Rubus argutus
Tila carolininana
Osmunda cinnamomea
Comus florida
Lyonia ligustrina/Lyonia racemosa
Lycopodium fabelliforme
Amianthium muscaetoxicum
Dennstaedtia punctilobula
Lonicera japonica
Hydrocotyle umbellata
Tradescantia rosea
Plantago sp.
Rhus radicans
Rhus vemix
Quercus stellata
Sorbus arbutifolia
Acer rubrum
Leiophyllum buxifolium
Sassafras albidum
Pinus echinata
Pinus elliottii
Myrica cerifera
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Southern Bayberry (Wax Myrtle)
Southern Magnolia
Spanish Moss
Swamp Mallon
Swamp Rose
Sweet Gum
Sweet Shrub
Wild Strawberry
TABLE 6-1
( continued)
Myrica cerifera
Magnolia grandifiora
Tillandsia usneoides
Hisbiscus moscheutos
Rosa palustris
Liquidambar styraciflua
Calycanthus floridus
Fragaria virginiana
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bayberry, and poison sumac. The herbaceous strata includes wild strawberry, poison
ivy, cinnamon fern, blackberry, and honeysuckle.
Fauna sightings were limited and included common grey squirrel, opossum, lizards
such as the green anole, luna moths, and passerines (or perching/song birds) such as
the brown headed nuthatch. Table 6-2 is a list of identified fauna.
The forested area was covered with leaf litter; therefore, tracks, casting, and scat
observations were minimal. The forested area appeared to be recently disturbed with
a few snags, which could be suitable habitats for raptors such as owls or other cavity
dwellers. The forested corridors are narrow and the area is surrounded by roads,
urban housing, and light industry, which can contribute to decreased species diversity.
The New Hanover Site has been significantly disturbed by repeated disposal and
remediation activities. Remedial activity has eliminated the burn pit, which served as
an artificial pond, and the topography of the site shows no permanent surface water
bodies onsite.
6.4 CONCLUSIONS AND LIMITATIONS
The State of North Carolina maintains a list of plant and animal species that are listed
as endangered, threatened, or a candidate for listing. The endangered species survey,
performed in April of 1991, did not identify the presence of endangered species of
flora or fauna at the site.
The flora diversity is typical for a coastal range area which has undergone significant
disturbance, remediation, and subsequent revegetation. No endangered flora species
were located. The dominant fauna on site were opossum, lizard and passerine
species. Species diversity was limited due to poor habitat, suitability, and stress,
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TABLE 6-2
IDENTIFIED FAUNA
NEW HANOVER COUNTY AIRPORT SITE
WILMINGTON, NORTH CAROLINA
American Crow
American Tent Caterpillar
Blue Jay
Brown Headed Nuthatch
Carolina Chickadee
Cope Treefrog
Five-lined Skink
Green Anole
Grey Squirrel
Ground Skink
Luna Moth
Northern Cardinal
Northern Mockingbird
Opossum
Purple Martin
Red Spotted Purple
Sandhill Crane
Spring Peeper
Tiger Swallowtail
Corvus brachyrhnchos
Malecosoma americanum
Cyanocitta cristata
Sitta pusilla
Parus carolinenis
Hyla versicolor
Eumeces fasciatus
Anolis carolinensis
Sciurus carolinensis
Scincella lateralis
Actias luna
Cardinalis cardinalis
Mimus polyglottos
Didelphis marsupialis
Progne subis
Basilarchia astyanax
Grus canadensis
Hyla crucifer
Pterourus glaucus
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which is a result of reforestation and urban impact from light industry, roads, and
housing adjacent to or nearby the site. No endangered fauna were observed.
Further seasonal observations are recommended to provide assurance that endangered
seasonal flora, such as the late spring bloomer Dionaea mucipula (Venus flytrap),
and/or endangered fauna were not missed during the April survey.
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7.0 DEVELOPMENT OF RISK-BASED REMEDIATION GOALS
To support remedial actions being considered in the feasibility study (FS) for the New
Hanover Site, a range of cleanup levels for groundwater was developed. These
Remediation Goals (RGs) were derived for the chemicals of concern which, based on
the quantitative risk assessment, have the potential in the future to impact the health
of exposed individuals via ingestion of groundwater or inhalation of contaminant
vapors.
Health-based RG concentrations for carcinogens are provided for target risk levels of
lx10·4, lxI0-5, and lxlO"°. The exposure assumptions for a given scenario are used to
back calculate to a concentration in groundwater associated with a specific target risk.
The risk assessment focused on quantifying potential carcinogenic risk which, for the
New Hanover County Airport Site, is at the upper boundary of the EPA recommend-
ed risk range of lxlo-4 to lxl0"° for ingestion and inhalation. Both exposure
pathways are considered in deriving risk specific concentrations in groundwater.
Equations used to calculate RGs for groundwater are based on assumptions developed
for the site as follows:
Volatile Organic Chemicals
RG = <Risk) (BW)(DY)(YL}
[(CSF1 x K X !Ra) + (CFS0) X !Ra] (EF) (ED)
Non-Volatile Chemicals
Carcinogens
RG = <Risk) (BW)(DY)(YL}
(CSF0) (EF)(ED)(IRa)
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Non-Carcinogens
RG = (RfD)(HI)@W)(IH'.)ffiD)
QRo) (EF) (ED)
RG = groundwater remediation goal (mg/I)
Risk = target risk (lx10·4, lxl0.S, or lxlO-,;)
HI = Target Ha7.ard Index (1,10)
BW = body weight (70 kg)
DY = days per year (365 d/yr)
YL = years of lifetime (70 yr)
CSF0 = oral cancer slope factor (mg/kg-dayf1
CSF1 = inhalation cancer slope factor (mg/kg-day)"1
RID -Oral reference dose (mg/kg-day)
K -volatilization factor (0.6)
IRo = ingestion rate (2Uday)
EF = exposure frequency (350 days/yr)
ED = exposure duration (30 yrs)
Resulting health-based RGs are summarized in Table 7-1.
To compare groundwater RGs with State or Federal water quality standards the
concentration suggested in the standard was used to estimate risk using the
assumptions presented for groundwater ingestion and inhalation in Section 3.0. The
groundwater quality standards yielded risks between 7x1Q-6 and lxl0·8• These risk
values, in Table 7-2, suggest that the enforceable groundwater quality standards
provide adequate protection against adverse effects.
Side-by-side comparison of potential remediation goals are provided in Table 7-3.
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Benzene
Chloroform
Chromium
TABLE 7-1
SITE REMEDIAL GOALS (RGs)
NEW HANOVER COUNTY AIRPORT SITE
WILMINGTON, NORTH CAROLINA
0.2 0.02 0.002
0.1 0.01 0.001
---I --I ---I 0.2
1,2-Dichloroethane 0.06 0.006 0.0006
Ethylbenzene 3.7
Lead ___ b ---b ___ b
NOTES:
2.0
37
• Chromium is not expected to volatilize during showering, and is not considered a
carcinogen by the oral route. No RG is appropriate for chromium based on
carcinogenic risks.
b Toxicity criteria are not available to derive an RG.
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Benzene
Chloroform
Chromium
TABLE 7-2
GROUNDWATER QUALITY STANDARD BASED RISKS
NEW HANOVER COUNTY AIRPORT SITE
WILMINGTON, NORTH CAROLINA
0.001 0.005 3 X 1Q·7
0.00019 0.1 1 X 10-8
0.05 0.05 0.3b,d
1,2-Dichloroethane 0.00038 0.005 4 X 10-7
Ethylbenzene 0.029 0.7 0.0Q8d
Lead 0.05 0.015 ___ c
NOTES:
2 x lo-6
7 x lo-6
0.3b,d
5 x lo-6
0.2d
___ c
• Risk estimated assuming groundwater concentration at NCAC standard or at MCL
and using exposure assessment methods described in Section 3.3.
b
'
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Chromium is not carcinogenic by the oral route.
No toxicity criteria available.
Value based on potential for noncarcinogenic effects, < 1 will not cause adverse
effects.
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TABLE 7-3
SUMMARY OF POSSIBLE REMEDIATION GOALS
NEW HANOVER COUNTY AIRPORT SITE
WILMINGTON, NORTH CAROLINA
Benzene 0.002
Chloroformb 0.001
Chromium ( +6) 0.2
1,2-Dichloroethane 0.0006
Ethylbenzene 3.7
Lead ___ c
NOTES:
• Based on target risk of 1 x 1 ~ or hazard index of 1.
h Total trihalomethanes.
' No toxicity criteria available.
7-5
0.001
0.00019
0.05
0.00038
0.029
0.05
0.005
0.1
0.05
0.005
0.7
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8.0 CONCLUSIONS
The baseline risk assessment performed for the New Hanover Site addresses potential
hazards to human health and the environment posed by the site in the absence of
remedial actions. Based on the evaluation of the sampling results for groundwater
and sediment and a general knowledge of the site history, the chemicals of potential
concern for the site were several metals and volatile organics (benzene, chloroform,
chromium, 1,2-dichloroethane, ethylbenzene, and lead) based on toxicity, frequency
of occurrence, and exceedance of water quality standards.
Consumption of groundwater is considered the primary pathway of exposure because
a residential area and several private wells are within a 3 mile distance of the site.
Inhalation of vapors during a shower is a secondary pathway of exposure for volatile
compounds. Contaminated soil had been removed from the site, which eliminated
this media as a potential route of exposure and risk. The sediment samples obtained
at the site did not demonstrate significant contamination or migration offsite. Surface
water was not present onsite. The estimated human health risk for the site, lx104, is
at the upper end of the acceptable risk range of lx104 to lxl0-6. Noncarcinogenic
effects are not expected following oral and inhalation exposure as the hazard index is
less than 1. Because no complete exposure pathways appear to exist for this site
(Section 5.1), these risks represent estimated future risks associated with residential
use of groundwater.
Based on the endangered species survey in April 1991, no endangered flora or fauna
were identified at the site.
8-1
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Health-based RGs for the chemicals of concern in groundwater were estimated at
three target risk levels. These RGs are site-specific and are considered health
protective for exposure by ingestion of contaminated groundwater and inhalation of
volatile compounds. Recommended RGs are presented in Table 7-1.
8-2
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REFERENCES
Agency for Toxic Substances and Disease Registry (ATSDR). 1990. Toxicological
Profile for Ethylbenzene. U.S. Public Health Service, Atlanta, Georgia.
Agency for Toxic Substances and Disease Registry (ATSDR). 1989. Toxicological
Profile for Chromium. U.S. Public Health Service. Atlanta, Georgia.
Agency for Toxic Substances and Disease Registry (ATSDR). 1989a. Toxicological
Profile for 1.2-Dichloroethane. U.S. Public Health Service. Atlanta,
Georgia.
Agency for Toxic Substances and Disease Registry (ATSDR). 1988. Toxicological
Profile for Lead. U.S. Public Health Service. Atlanta, Georgia.
Agency for Toxic Substances and Disease Registry {ATSDR). 1987. Toxicological
Profile for Benzene. U.S. Public Health Service. Atlanta, Georgia.
American Conference of Governmental Industrial Hygienists (ACGIH). 1990.
Threshold Limit values and Biological Exposure Indices for 1989-1990.
Cincinnati, Ohio.
Casarett, L.J. and J. Doull. 1986. Toxicology. The Basic Science of Poisons.
J. Doull, C.D. Klaassen, and M.O. Amdur [eds.] Third edition. MacMillan
Publishing Co., Inc.
CDM Federal Programs Corporation (CDM). 1991. Draft Endangered Species
Survey Report for the New Hanover County Airport Bum Pit Site.
Wilmington, North Carolina. Prepared for: U.S. Environmental Protection
Agency.
Clement Associates, Inc. 1985. Chemical, Physical, and Biological Properties of
Compounds Present at Hazardous Waste Sites. Final Report. Prepared for the
U.S. Environmental Protection Agency.
Deer, W.A., R.A. Howie, J. Zussman. 1982. An Introduction to the Rock Forming
Minerals. Longman Group Limited.
Dehn, E.N. 1991. Letter by E.N. Dehn, Director of Airport Engineering and
Maintenance, to D. Burks, Environmental Specialist with New Hanover
County Environmental Management regarding the New Hanover County Bum
Pit. November 6th.
R-1
NHAN009.014
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Driscoll, F.G. 1986. Groundwater and Wells. Second Edition. Johnson
Division, St. Paul, Minnesota.
Ellenhorn, M.J. and D.G. Barceloux. 1988. Medical Toxicology: Diagnosis and
Treatment of Human Poisoning. New York: Elsevier Science Publishing
Company.
Hayes, R.B., A. Sheffett, and R. Spirtas. 1989. "Cancer Mortality Among a Cohort
of Chromium Pigment Workers." American Journal of Industrial Medicine,
16: 127-133.
Ivankovic, S. and R. Preussmar. 1975. "Absence of Toxic and Carcinogenic Effects
After Administration of High Doses of Chronic Oxide Pigment in Sub-Acute
and Long-Term Feeding Experiments in Rats." Food and Cosmetic
Toxicology, 13:347-351.
MacKenzie, R.D., R.U. Byerrum, C.F. Decker, C.A. Hoppert, and R.F. Langham.
1958. "Chronic Toxicity Studies: Hexavalent and Trivalent Chromium
Administered in Drinking Water to Rats." American Medical Association
Archives of Industrial Health, 18:232-234.
North Carolina Administrative Code (NCAC). 1989. "Classifications and
Water Quality Standards Applicable to the Groundwaters of North Carolina."
Title 15, Subchapter 2L. Current through August 1,1989. Environmental
Management Commission. Raleigh, North Carolina.
Shacklette, H. T. and J.G. Boerngen .. 1984. Element Concentrations in Soil and
Other Surficial Materials of the Conterminous United States. U.S. Geological
Survey Professional Paper 1270. United States Government Printing Office,
Washington, D.C.
Shroeder, H.A. and M. Mitchner. 1975. "Life-Term Studies in Rats: Effects of
Aluminum, Barium, Beryllium and Tungsten." Journal of Nutrition,
105:421-427.
U.S. Environmental Protection Agency (EPA). 1992. Remedial Investigation for the
New Hanover County Burn Pit Site. Environmental Compliance Branch.
Hazardous Waste Section. Region IV EPA, Athens, Georgia. January.
U.S. Environmental Protection Agency (EPA). 1992a. Integrated Risk
Information System (IRIS) Database. Office of Health and Environmental
Assessment. Washington, D.C.
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U.S. Environmental Protection Agency (EPA). 1991. Drinking Water Regulations
and Health Advisories. Office of Drinking Water. November.
U.S. Environmental Protection Agency (EPA). 1991a. Fact Sheet: National Primary
Drinking Water Regulations for Lead and Copper. Office of Ground Water
and Drinking Water. Washington, D.C.
U.S. Environmental Protection Agency (EPA). 1991b. Health Effects Assessment
Summary Tables (HEAST). FY-1991 Annual. Office of Research and
· Development. Office of Emergency and Remedial Response. Washington,
D.C.
U.S. Environmental Protection Agency (EPA). 1991c. Memorandum from Dorothy
E. Patton, Risk Assessment Forum to F. Henry Habicht, Risk Assessment
Council, titled: "Guidance on Estimating Exposure to VOCs During
Showering." July 10.
U.S. Environmental Protection Agency (EPA). 1991d. Risk Assessment Guidance
for Superfund. Volume I. Human Health Evaluation Manual. Part B -
Development of Risk-Based Preliminary Remediation Goals. Interim. Office
of Emergency and Remedial Response. Washington, D.C.
U.S. Environmental Protection Agency (EPA). 1990. Corrective Action for
Solid Waste Management Units (SWMUs) at Hazardous Waste Management
Facilities. EPA/SW-530-90-012. Proposed Rule.
U.S. Environmental Protection Agency (EPA). 1989. Risk Assessment
Guidance for Superfund. Volume I. Human Health Evaluation Manual (Part
A). Interim Final. Office of Emergency and Remedial Response.
Washington, D.C. and the Supplemental Guidance: Standard Default Exposure
Factors. 1991. OSWER Directive 9285.6-03.
U.S. Environmental Protection Agency (EPA). 1989a. Risk Assessment
Guidance for Superfund. Volume II. Environmental Evaluation Manual.
Interim Final. Office of Emergency and Remedial Response. Washington,
D.C. EPA/540/1-89/001.
U.S. Environmental Protection Agency (EPA). 1987. Health Advisories for 25
Organics. Office of Drinking Water. Washington, D.C. PB87-235578.
U.S. Environmental Protection Agency (EPA). 1985. Health Assessment Document
for Chloroform. Washington, D.C. EPA/600/8-84-004F.
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U.S. Environmental Protection Agency (EPA). 1984. Health Effects Assessment for
Trivalent Chromium. Cincinnati, OH: ECAO-CIN-H035.
U.S. Environmental Protection Agency (EPA). 1984a. Health Assessment Document
for Chromium. Research Triangle Park, NC. EPA-600/8-83-014F.
U.S. Geological Survey (U.S.G.S.). 1970. Geology and Groundwater Resources of
New Hanover County, North Carolina. Prepared by G. L. Bain, U.S.G.S.
Division of Groundwater. Groundwater Bulletin Number 17. North Carolina
Department of Water and Air Resources. Raleigh, North Carolina.
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n APPENDIX A
D CONFIRMATION SAMPLING RESULTS
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------
•·:-· ,•·:-::-,:. :--,_·.',:/-
•··.····· ...... ... ·•··
:
ii )/ •{ {
lnorganic Element• (mg/k.g)
Chromium
Lud
Barium
Copper
Nickel
Vanadium
Ynrium
Zinc
Aluminum
Mangancac
Calcium
Magneaium
Iron
Pota11ium
Extractable Organics (µg/kg)
Pbcnanthr-enc
Anthnccnc
Pvrene
NOTES,
NA -Not Analyzed
J -Eatimated Value
15
500
8,200,000
610,000,000
61 000 000
!!!!!!!!!I !!!!I
TABLE A-1
SOIL CONFIRMATION DATA SUMMARY· DECEMBER 1990
SEDIMENT AND PIT
(.9
1.11
481
5
I.8
NA
26
1500
240
1501
NEW HANOVER COUNTY AIRPORT SITE
WILMINGTON, NORTH CAROLINA
4.3
I IJ
8.3
5.8
NA
26
4900
260
140
7301
130
3.2
7.41
7.1
3.2
NA
18
2,600
410
5901
2.8 2.9
8.51 131
4.9 21
131 6.61
2.9 3.4
NA NA
18 36
2500 2200
8.3
460 1100
100
5001 7301
981 3501
3
231
13
6.61
3.9
NA
40
2800
4.4
1300
ISO
7801
120
7801
Material was analyzed for but not detected in the sample.
aiiliil fii!II
2.2 3
2.61 18J
6.6
l1J 141
2 3
NA NA
27 32
1,500 2200
3.7
92 890
98
400J 5601
2,000J
l!!!!!!!!!I
2.2
6IJ
5.4
2.1
NA
1700
3.7
1200
130
5401
2401
531
2501
I!!!!!!
3.2
7.61
3.2
NA
2800
300
130
5201
3201
501
2.9
7.31
5.6
121
3.3
NA
14
2400
2.6
330
6201
11111111
-----
Naphthalene 8,200,000
l•Mcthylnaphthalcne 8,200,000
Bcnzo(a)&nthraccnc 310
Chryaenc 310
Bcnzo(B and/or K)Ftuoranthcnc 310
Bcnzo(a)Pyrcnc
Octahydrohcxamcthylindcnc
Ethyldimcthylbcnzenc
l •Mcthylnaphthalcnc
Dimcthylnaphthalcnc
Trimcthylnaphthalcnc
Dihydromcthanonaphthalcnc
3 Unidcn1ificd Compound■
9 Unidentified Compound,
10 Unidentified Compound■
11 Unidentified Compound•
12 Unidentified Compound•
15 Unidentified Compound•
16 Unidentified Compounds
18 Unidentified Compounds
19 Unidentified Compouncb
Pelrolcum Product
NOTES:
NA -Nol Analyzed
I -Estimated Value
Material waa analyzed for but not detected
--
3,700
20001
100,00W
N
in the sample.
l!!!!!!!!I
TABLE A-I
(continued)
-4,000JN
90,0001
N
l!!!!!!!I liiiiiil liiil l!iiilii 1!!!111
1,6001
37W 960J 11,000 3,200
160J
1501
2501
831
20WN
2,00WN
2,00WN 9,000JN
20,000lN 2,00WN 7,00WN
6,00WN
2,00WN 10,000JN
200,00W
8,00W
10,00W 60,00W
200,00W
200,00W
60,00W
N N N N N N N
•-=
--
Purgcable Organic, (µg/kg)
Bcoune
Ethyl Bc~nc
Total Xylene■
Decanc
Dimcthylhcptanc
Nonanc
Propylhexanc
Ethylmcthylhcptanc (2 l.somcn)
Trimcthylheptane
Ethylmethylbenzene
Trimethylbenzcnc
Trimethylnonane
I Unidentified Comnound
NOTES,
NA -Not Analyzed
J -Estimated Value
410
200,000,000
3,000,000
-
Material waa analyzed for but not dctc.cted in the sample.
- -
1401
2,600
3,900
-
TABLE A-1
(continued)
-
5,000JN
3,000JN
2 ()()()J
l!!!l!!I !!!!!!!
420!
1,100!
30,000JN
4,000JN
8,000JN
5,000JN
6,000JN
3,000JN
4,000JN
10,000JN
7 .OOOJ
l!!!l!I l:iiiiil liiiiiiil liiil!!I
-- ------!!!!!!!!!I !!!!!!!!!I l!!!!I !!!!!!I
Inorganic Element• (mg/kg)
Chromium IS
Lead 500
Barium
Copper
Nick.cl
Vanadium
Zinc
Aluminum
Ma111aoeae
Calcium
Maaocaium
Iron
Pol.auium
~xtnctablc O[Xanic Co~ound1 (µg/kg)
2-Methylnaphlhalcne 8,200,000
Naphthalene 8,200,000
Fluoninthcne 82,000,000
Py«nc 61,000,000
NOTES:
J -Estimated Value
--Material wH analyzed for but not detected in the aamplc.
TABLE A-2
SOIL CONFIRMATION DATA SUMMARY -DECEMBER 1990
PIPELINE AND TRAININO AREAS
NEW HANOVER COUNTY AIRPORT SITE
WJLMINOTON, NORTH CAROLINA
4
5.4J
5.5
24J
5
2S
4,100
3.9
3IO
140
l,JOOJ
130
SOI
3.3
4.5J
2.7
21
2,800
77
4400
2.6
3.4J
2J
2.8
18
2,200
140
5000
420UR
420UR
420UR
420UR
3.1
4.BJ
4.8
2.9
23
2,400
500
550J
2.8
4.IJ
35J
3
42
400
66
6001
U -Malcrial wu analyzed for but not detected. The number i1 the minimum quantitation limit
2.3
8.2J
2.7
20
2,100
3601
63J
1,600
2.8
3.IJ
2.1
18
3,000
83
680J
48J
==
4.3
l9J
9.3
l2J
3.2
68
1,600
20
260
96
7,600J
l,IOOUR
l,IOOUR
l,IOOUR
l,IOOUR
==
5.2
. 38J
29
l6J
7.1
3.4
110
1,4000
14
280
5,000I
380UR
380UR
380UR
380UR
R -Quality Control indicalca that data arc unusable. Compound may or may nol be present. Rcsampling and rcaoaly1i1 ia ~cuary for verification. The value is that reported 'by lhc Jabontory.
== ==
2.1
3.2J
1.7
23
1,600
200I
~019
--
Extnctablc Organic Compound• (µa/kg)
Diethyl Phthalatc
Phenylcthanonc
Tctrahydromethanoindcnc
Ethyldimcthylbcnzcne (2 isomen)
Mcthylpropenylbcnzcnc
Tclnmethylbcozenc (2 iaomera)
I Unidentified Compound
2 Unidentified Compound■
.S Unidentified Compound•
7 Unidentified Compound■
20 Unidentified Compounds
Petroleum Product
Purgcablc Organic Compound• (µg/kg)
Ethyl Benz.enc
Toe.al Xylene,
Jill!§,
J -Estimated Value
-
200,000,000
3,000,000
--Material wa■ analyzed for but not detected in lhc umplc.
-
30,000J
N
- -
TABLE A-2
(coa~ued)
68J
80JN
6001
◄20UR
U -Material WH analyzed for b~t not detected. The number i■ the minimum quantit.ation limil
-
5,000
--
5,000J
3,000JN
l,OOOJN
JOOJN
2,000JN
6,000J
!!!!
◄O,OOOJ
N
n
◄60
!!!!!!!
1,IOOUR 380UR
R -Quality Control indicatea that data arc unuaablc. Compound may or may not be procnt. Rcaampling and rcanalyaia ia neccaaary for verification. The value is that reported by the laboratory.
==
IOOJN
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TABLE A-3
GROUNDWATER CONFIRMATION SAMPLE DATA SUMMARY -DECEMBER 1990
NEW HANOVER COUNTY AIRPORT SITE
WILMINGTON, NORTH CAROLINA
1111111111
Inorganic Elements (µg/L)
Mercury
Extractable Organic Compounds (µg/L)
2-Methylnaphthalene
Naphthalene
Diethyl Phthalate
Di-N-Butylphthalate
2,4-Dimethylphenol
Trimethylcyclopentenone
Trimethylhexanoic Acid
Methylnaphthaleneacetic Acid
Naphthopyrandione
Petroleum Product
2 Unidentified Compounds
10 Unidentified Compounds
17 Unidentified Compounds
Purgeable Organic Compounds (µg/L)
Benzene
Ethyl Benzene
Total Xylenes
Pentane
Methoxymethylpropane
Ox ybispropane
Tetrahydrothiophene
Trimethylbenzene
Ethylmethylbenzene (2 Isomers)
Propylbenzene
3 Unidentified Compounds
NOTES:
NA
J
Not Analyzed.
Estimated Value.
200
200
1.0
29
400
Material was analyzed for but not detected in the sample.
A-3
1J
1J
19
22
200J
7JN
2J
2J
20JN
SOJN
40J
8J
1J
2J
1.60J
15
70JN
300JN
NA
20001
210
120
2J
lOJN
lOOJN
20JN
60JN
40JN
60JN
SOI
NHAN009.018
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APPENDIX B
PRELIMINARY REMEDIATION GOALS (PRGs)
NHANOOJ.023
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MEMORANDUM
DATE:
SUBJ'ECT1
FROM:
TOI
THROUGH:
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION IV
:34!5 COURTLANO STREET. N.E.
A.TL.ANT.A. GEORGIA 3036S
January 23, 1990
Preliminary Remediation Goals for-the New Hanover
County Airport Burn Pit Site.
Rebecca Fox~
Toxicologist
Fred Sloan
Environmental Services Division
Elmer Akin~
Health Assessment Officer
Per your request, I have developed preliminary remediation
goals (PRGs) for the New Hanover County Airport Burn Pit Site.
The PRGs for soil and groundwater and the supporting
documentation are contained in the attached report.
Please contact me if you have any questions or if I c~n be of
further assistance.
Attachment:
cc: Jon Bornholm
Remedial Project Manager
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PRELIMINARY REMEDIATION GOALS FOR THE NEW HANOVER COUNTY
AIRPORT BURN PIT SITE
The New Hanover County burn pit is part of an active airport
and was used from 1968-1974 for fire training exercises.
During this period, it has been estimated that 100 to 500
gallons of jet fuel were burned in the pit daily. The pit has
an area of approximately 1500 square feet and is surrounded by
a two foot e·arthern berm. . Water released from the pit was
allowed to flow onto the land. surface. The site soils are
sandy with a rapid lnfiltration rate. The surficial aquifer is
approximately five to seven feet· below· ground surface.
A removal action was performed at the site in November 1990, in
which contaminated soil was removed from the burn ~it, the
training areas and the supply tank. Site analytical data
-represents pre-removal conditions.
The purpose of this document is to develop chemical specific
preliminary remediation goals (PRGs) to assist in site decision
making. PRGs are concentration goals for site contaminants of
concern for specific medium and land use combinations. There
are two general sources of PRGs1 (l) concentrations based on
ARARs and (2) concentrations based on risk assessment.
The first step in the PRG process is to identify the media and
contaminants of concern. The media of concern at this site are
contaminated soil in and surrounding the pit and groundwater
which may be contaminated as a result of the leaching of
chemicals from the soil. The initial contaminant of concern
list contains chemicals which.have been previously detected at
the site and chemicals that the site history indicates are
likely to be present. The contaminants of concern will be
modified as more site data is collected. Table l contains the
initial list of site contaminants along with the toxicity
values used in the risk calculations.
Since the site is located on the property of an active airport,
it is felt that the most likely future land use for the site is
commercial/industrial. For this reason, the soil PRGs were
based on exposure assumptions for a commercial/industrial
future land use. However, the residential exposure assumptions
were used to address the groundwater pathway, since the closest
residential area is approximately 0.25 miles from the site and
if the groundwater is contaminated the plume could migrate
offsite to the residential area.
Initially, all possible ARARs were identified for the
groundwater pathway and presented along with the risk
associated with the most likely ARAR concentration. Uhen ARARs
did not exist, risk-based concentrations were calculated using
standard default exposure assumptions.· Figure l contains the
equations and the exposure assumptions used to calculate the
health-based groundwater PRGs for the carcinogenic and
noncarcinogenic contaminants of concern. The risks associated
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with :the ARAR concentrations were calculated by rearr?.r,ging these··equations and solving for either the target risk for carcinogens or the target'hazard quotient for noncarc~nogens. Table 2 sUJIIIIUlrizes the potential groundwater ARARs, ti1a risk at the ARAR concentration, the risk-based concentration for chemicals without ARARs and the contract required qua~titation limit (CRQL) for the preliminary contaminants of concern.
Since there are no ARARs for soil, the soil PRGs were based on calculated health-based concentrations. -Soil.exposura which was :·considered-under the commercial/ industrial. scenario evaluated --intake ·of 'the contaminant. by direct ingestion, inhalation of volatile organics from the soil and inh~lation of semi-volatile organic compounds absorbed to soil particulates. The_soil intake calculated from these exposure pat~ways is combined with the toxicity information contained in Table l to develop risk-based PRGs. The equations and exposure assumptions for the soil PRGs are contained in Figure 2. Table 3 swnmarizes the soil risk based PRG concentrations. Figure 3 and Table 4 contain information used in deriving the special paiameters for the soil-air pathway.
The PRGs contained in this report are initial PRGs ba$ed on preliminary site infor111ation. The PRGs will be modified during the RI/FS process to reflect the data collected during the remedial investigation. Modifications will be based on a reevaluation of the media of concern, the contaminants of concern, the land-use assumptions and exposure pathways, toxicity infor111ation and potential ARARs. The modifi~d PRGs will be contained in the baseline risk assessment and ,lill better reflect the actual site conditions. [The PRG development was based on the Review Draft Guidance for Part B of the Human Health Evaluation Manual (Development of Preliminary Remediation Goals). The modified PRGs will also reflect changes made in future guidance revisions.]
D
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m. ... l.DU&U.1' CCIIUIIDWl'tS or COIICIIUI &IID ':OUCI'f"l' Iar<>IUIATIOII
txpoaur, Rous•, rna11s1on E Cllaaic&l llat'ue.n.ce Source Slope Wei9ht source
001■ (IUD) raceor ot' •Yi.dance
I (mq/k<j-d&J) (mq/k<j-d&f)-l
. z..n-2 ... IRIS knlUe
lthyl ,;tenz■n• 1.1 ... 1-: IRIS·
I 2-.autanoae (JCIS.) n-2 IRIS
Neehylon■ Chloride H-2 IJUS .7, 51.-3 82 IIUS
TOlu■no 2•-1 IRIS
I XJl■a■ 21+0 IRIS
C&rci.n09enic ....... 1.151+1 u ICAI)
aoacarcin09■aic .......
.a.:uapth■a• ,s-2 D.UT
I Atl'tllrace.ae 31-1 IIZAST
l'luorantb■n■ 41-2 D.UT
l'luor■n• 41-2 llllST
I Sapbt.halea■ 41-3 D.UT
Pfr•n• 31-2 D.UT
~•r PU. 41-311 D.UT
I
i:.¢•
ChrcaJ.ad 51-3 IRIS 82 IIUS
AraanJ.a 11-3 IIIAft 1. 11+0 IRIS
I
I mo■ur, !!9USl1 tnn,1,s10n
a.a.sen■ 2.n-2 ... IIUS
IUlfl aoazane
I z-autanoa■ (111111:) H-2 a.u-r
Na't.byl■a• cbloride n-1· IIIAft 1,'11-2 B2 IIUS
%0111811-9 u-1 BU.ST
I 1.ylen■ H-2 BU.ST
C&rclJloqenic ....... ', 11+0 82 •= 110ncarci.no9■Aio ......
I &c:anapb eheaa
&llth.racua
l'luoran t.tlane
I nu.oru.■
S&phtba.l■a.■
Pyr■n•
other PAJIII
I Laa.de
ChrcaJ.wa d 61-7 D.UT 4.11 ♦1 ... IRIS
Ar■■nic 51+1. ... IRIS
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E m m I I • I I II I a I d I I I I I I I I I I !:Alita I (Cont.) ·••i..1•1•a.a·:r co.a-r.a.•1•a.■:r1 or .co■c••·· a.■ 0 .TO.ZIC ITT lHPOR:<ATIO• Ia?S • IDta9r~t•d a1■t Iaformat1on SJ■t•• S1.1m■a.r7 Table KIAST • Bealtb •ttect■ ICAO • la•iroa■■at•l C.rit■r1a aad A■••••••nt O!!l.co 1.'b■ ■lope factor tor bmi~~(!~PJna■ vu u■ed ·tor Lll c·ucin.c9■nic pua. ft■ follovi.D9 PU■ vb.icb u■ ccnta.J.ned on tb■ tuq■t compound liat u■ clu■J.tied u carcin041■aJ.c1 benz(■)&11tbrac■n■, baazo(b)flYO.ruth■n■, banao(t)t'luorant.b■ n■, cbrya■n■, dibenz(a,h) anthrac:■n■ and ideao(l,2,l-c,d)pyraa.■• .• fll■ r■t'aruc■ do■• tor naph~al.■n■ va■ 11■ad for aoncarcino9■nic PABa vtlicb do not baY■ an A.ca■ncy •uit'ied 11D. ft.■ A4acr hu ao·••ritied t.ozicity ••lu■■ tor l■ad. 'fl'!.■ Aq■nc:y 1.■ racoaaendJ.Dg Uat l■&d b9 ••aluat■d ~, 1.ncorporatitlq ■it■ ap■citic 1.Dt'ormatioa into th■ lead O'pt&ka/Biokin■tJ.c (tJBJt) modal. Th■ IJBJt modal vu 11aed to det.arm.1.D■ a ao11 l■&d PtlG for U.1■ ■it■• 'l'be toaic:itT T&lue 1• for bazaT&l■n1: chroaiwa. Th• r1■k D&■ed c&lculat1ona c:ouervat1Te1J uaume e.ba1: all ch.ramiua ia iJ1 the baaY&lant fora.
D D m I • I I I I I I I I I I I I I I TAILI 2 •r•11a1aarr Grouadwat•~ ••••diatioa Qoal• Chaaical ::!!l£l -·-2-autanoce(NII) •J.b.rl aaaun• .. tllfl■a■ Chloride Toluene .IJlen■■ ~ Carcl.aoqonJ.c PAiia BeAI ( & ) aDUU'IIDc■a.■ Beazo1 t1.) tl~ran~■n■ a.nae( k) tluoran't.hen■ Olrya■n■ AIIA&. Stat■ NC%. ltate Stat■ NCI.a IICl. Stat■ PIICt, Stat■ NCI.a IIC, Stat■ ~ IIC, PIICt.b Diben1(a,b,Juthracen■ IdaDo(l,Z,3-c,d)pT?"■D■ llon C&rc1.Do9■a1c PAiia Acaaphtbau■ Aa.t.hracene rluoran'thaa• •louar-lapb~al .... p,yr..,. 2-~Tl n&phtllalen■ a.a.10(9,b,1) "PUTla■ Phanan~an■ Aa.t.hrac:■n■ AMII cancer HQ at Ri■lc-.ba.aed conc■nt.ration JU.ak at AIIAII concentration (mq/l) (m,;/1) AIWl 10-6 IUak HQ• l O,OOl(HCI J.H-1 0.005 0,17(PRCJ o.s O,Olt(Pll<ll 0,001 o., o., 0,005(PIIQJ '·"-' 0,003 0.005 l.O(PRCJ 0,2 1,0 1.0 0,4(Pll<ll 0,J · 10 10 O. •J002(PRGJ 2,H•5 ·-~-, 2,l(PRQJ 11,l(PRQJ 1,S(PRQJ l,S(PRCI 0,l(PRCI 1,l(PRQI O,lc(PRQI 0.2c(PRQJ 0,2c(PRCI 0,2c(PRCI CRQL 0.005 0.005 0,005 0,005, 0.005 0,005 0,01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 O.Ol
I m I I I I I I I I I I I I I I I I I ,1,..,. 2 loU -llqv&U.ODI for c-rc1&1/IJUl•••r1&1 I.&nd O••· -Cuc1.aoqu.ic IJ.11£-Dued '""'""'11 :ns 1 1w a at a lf! d1x11,,,, D • D • [(lr0 a 1o•'lk9/mq & ta•o.i.l) • (SP1 & taair a (1./W • l./ftP11·1 PVM151£1 n "1 IPo .. u ., Ill n,ooil Ia&.U ff nr PttloU!eo t unit'■, tar;■t ac••• i.Ad.1.Yidual. lUet.1.M cancer riak ( u.nitl•••) • -1 1Dll&lot1oo. cucer ■lop• factor ( ("'/k9-cl&fl I . . -1 onl C&DCU •1-·f&etor I ( .. /k9°c1&r1 ) od•lt-,. w19ht (kV) ann91A9 ti.-(Jnll upo1ur1 freqyencr (d&f■/,rJ ezpa■lil."I du.ration {frl) ■oil 1Af■■Uoa rate ("'/d&TI 1.n.halatioa rata of &J.r ca3/d&y) t'Olatil1a&t1oa factor 1•1 /kqJ niap1zu1• partic:11lat.e ..S..11.oc factor I I• I U 5 lfl dttl/TIK ~ LO _, cneal.c&l ■-1f1c chaic&l specit:ic 70 kf 10 rr■ uo ur■trr 40 ,.. 50 .. ,u, u a3tc1&1 Pique J S,2 JI 107 a3/k9 (Pi.,,.... J) llan-carc1:loqeAi.a aJ.ak-t:l&Ded • na, .. ,1, SIi a U a I ( I/UD0 a I~ k9/ .. • u..,ul • (I/RtD1 a IJl&.U a II/VP• 11nr111 PHws,r■ TIIQ .. u ff Ill UD0 atD1 za..,u , •• ir ff PIP PIClniSiPD fY.Pitll tuqet llu&rd q,,otiat (WlitleHJ ad111t -,. ... 1,n• (qi aevaqJ.Dt U.. (Jnl _..,. bac &DDT (clara/JSI wo: a--• toe (yn) oral l"Pf o -1 .. /q-clar, fnPttles1M ..: ...... dNe (99/q'-d&f) NU : n I rte" z&&a ,at1MrJ d&i..'.·r 1All&l&UGD rat■ ca1 /q'J t'Ol&tilia&u.oa factor (al/kqJ ra1-pirabl1 p&n.J.culata a.i■■ioa fact.or n.iia 1.0 70 liq 40 ,re ( &lvar■ oq11&1 to ID l 250 c1&retrr 40 ,.. ch.al.cal opec:Uic ah.al.cal ■-Uic 50 '"!1/cl&J u •J /cl&J Pique J S,2 a l07a3/kf (Fif•r• JJ • Th■ VP t■ra vu 1i11ed to ffalu.at■ tha air pathv17 tor 'l'Ol&til■ or9a:i"ic COlllpauAda. fll■ nr tars vaa \/iaed c.o Ht.i a.Lr coniaainut 1At&.ta tor th■ part.1.wlata patllvay.
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•r•limtnarr Soil ••••d1at1on Qoala
Cll-.J.cal
vo11sil1 organic compoyode
BeAz•n•
1u11 bansan■
z-■utanone
•t.hrlua chlod.da
Tolan•
Z7lanu
lpJ.-Volatilt organic compoundf
C&rcitlocJanic PA.Ba
.. ns(a)anth.rancana
lenao(D)t:luoranthana
kc&O(k)t:luoranthena
Chryaane
Dibena(a,b,)antbracana
IdaDo(l,2,l-e,d)pyr■na
11o11earcin09enic Pua•·
&canapbtbeaa
.\AtArlleU&
rluorutb■n•
nu.on.a■
■apAU&lua
m-
2-tbfl napbth&laa■
Bea.10 ( g', b·, J.)perylaa•
ftea.ua'C.hren•
Inoaen1s1
&.rauic
c:hrcm1wa
r.ld
IIQ • llaaard OW,ileat
Riak•b•••d Concentration (m9/k;)
10•' IU.■k BO• l
4.01-l(PRG)
2.01♦51 (PRG)
2.51+l(PRG)
l.51+0(PRG) 1.71+3
7.tl+l(PRG)
3.01+3(PRG)
3.11-l(PRG)
l.ll♦5(PIIO)
l.ll+!(PRG)
l.21+4(PRG)
l.ll+4(PRG)
l.21+3(PRG)
6 .11+4( PIG)
1.ll+J11 (PRG)
8.ll+l11(PRG)
l.ll+31>(PRG)
l.71+0(PIIC)
l.51+1°(PRG) 2.11+2
5.Ql+ld(HQ)
OQL • cauract llaq,&lnd Qaailt1U.0n LiaJ.t
I fll■r• 1a not a11 atw, Yarit'iad 1.a.b&lation R!t> t:or t.h1• compound or· compowida. oral azpoaur■ rou'ta.
CRQL (mg/kg I
51-l
5E•l
lE-2
51-l
51-3
51-3
3.ll-1
3.ll-1
l.ll-l
l.Jl-1
l.ll-l
l.JE-l
l.ll-1
l.Ja-l
l.ll-1
l.lS-1
Th.a PRG i■ based on 'Cb.a
Thar■ 1• not an a9enc:y-•■rit:1ad .UD t:or tJ:11■ CCldlpOWJ.d. ft■ PltG 1a baaed on th■ oral Rt:%> t:or a.aptM.hal•n•.
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d
'fb•r• 1• not an A9ency-veriflecl oral ■lope factor for tJlia ccapond. The ca.rcino9enlc r1ak-C•s•d PRG i• bued on the inh&l.at.ion ■lop. fa=tor.
ftera are no curnnt A9enc1-•u1t1ed tozieoloqlcal ••lu•• tor Vhlch a protective 1011 cleanup l•••l can be da•eloped. '?ha PRG vaa developed by ualnq the IPA Upt&k■/liokin•tic (UB&) aaodal tor l•ad. tba aodal vu run u■iz19 the ■tudard azpoaura default •aluee lAcorporatad into _tbe -=»del. The IDOd■l 1■ l)uad on tbe e:zpc■ure of iAfuu and yowuJ ·children 1D a r■aidaDU.al acanario.
" • .. .. • ... ..
.. • • .. .. • • .. ... ..
' .. ...
0 •
• n .. ..
0 ..
• .. • .. • • .. .. . .. • .. .. ...
u • "' • ..
0 ..
• ..
0 ... .. • .. .. •
--
N
I ..
►
..
u ..
• .. ..
N -... • " ..
N
V ,;
8
N
N • N .. p -• 0 ..
•O -0
N
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N
N ..
" 0 .
0
.. l .. . .. 0 ..
N
I
.. 0
• 3 • a
1 j ..
l
.B
ll
1 • ~ .. ..
! .. s
i
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.. 0
..
• :a
• ~ ~ ..
r:
I t .. ..
8
.a
a 0
J
! • I u
u
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1 j ... • ... ..
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..
• "
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··•~I•r ■Aar CO ■TA•I ■A ■TI o, co ■c••· AID T01%C%Tt %RP0RKAT%0 ■
Cb-.1.cal B
( at.m.-m.3 /mol)
......... ,~u-, ,.,1+1 5.431-3 1.041+3
ltllyl au111U ,.s■-2 1., •• 1 1.,01-3 4.521+3
.z .. au~one 1.101-2 4.S l+O 2.1u-5 ,.1,1+3
Nathfl•n• ctllorid• 1.001-1 1.71♦0 2. 5751-3 1.711+3
Toluene 1,701-2 2.11+2 1.111-3 l,'81+3
1,1 .... 7.151-2 1.u+1• l.2H-lb 4.t,l+l
• Valu r-.prNaD'ta u aTW•9• of' 0 1 p and • syl■ne.
b Value rwpre■aau an ••va.c;• of o &a.d a r,l■ne. ·
Molecular dJ.ffuaJ.•itJ i.D. air. V&luaa obc.aJ..aad fraa IPI U£1Sup•rfund ttaeional Techn1c•l au1danc9
Stsdr s,r1,,. volumt rt, l■Simation 9# ,,,,11n• Ai£ P111ton1 pt Sup■r;ynd Sit••· AU.quat 1990.
K00 OquJ.c-carJ:loll pU'U~tJ.on coet:f.l41ant dari•ec:I t:rc:a loq loc: ••lu.e■• toq .._oc value.a ~u.i.aed
fraa tr&1nila9 ~ frc:a the lllpu'fu.ad tJni•■i·■itJ Tr&J.AJ.Jiq tn■titute (SlnI) Workal:.cp entitled,
nlR■P9G Md bH 9( 92:P!IPIDMt.l in tht su;,aurt•c:■, s.i,t.asNr Uta.
• a.nr,•1 law oouatu't. "9ala.u ,,_.. obt&lned from ta9 1VT't ttaini.n9 11&D~al nf■r.ncad above •
ff Volatilisation Pactor. Value vu deriYed frcm equation contained in Piqure 1.
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APPENDIX C
LIST OF ENDANGERED, THREATENED OR CANDIDATE SPECIES
OF FLORA AND FAUNA
FOR THE STATE OF NORTH CAROLINA
NHAN009.023
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LIST OF NORTH CAROLINA'S
ENDANGERED, 'nU!.EATENED. AND CANDIDATE PLANT SPECIES
FEBRUARY i990
PLANT CONSERVATION PROGRAM
PLANT INDUSTRY DIVISION
NORTH CAROLINA DEPARTMENT OP AGRICULTURE
JAMES A. GRAHAM, COMMISSIONER
This is the official list of Endangered, Threatened and Candidate
plant species of the state of North Carolina. The list is
maintained by the Plant Conservation Program in the North
Carolina Department of Agriculture. This list supersedes all
previously published lists.
Cover illustration by Carol Ann Moorhead
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NORTH CAROLINA'S RARE PLANT SPECIES
AH INTRODUCTION
The earth's biological diversity, that is, the number of
different plant and animal species, the habitats and ecosystems
in which they occur, and the genetic diversity and variation they
contain, is being rapidly depleted. Our own species is dependent
on this biolog·1.cal diversity for medicines, agriculture,
industrial·· products, recreation, and our psychological heal th.
Furthermore, we are ethically responsible for its protection.
Rare species have come to represent our nation's commitment
to protect biological diversity. They are indicators of uncommon
and diminishing habitats and, many times, rare species are the
first to show decline in biological diversity and the health of
an ecosystem. The federal Endangered Species Act and similar
legislation in many states have directed resources toward the
protection of rare species. But while the emphasis is on rare
species, their survival can be ensured only by protecting the
habitats and ecosystems in which they occur and the range of
life-sustaining genetic diversity that they contain.
North Carolina is blessed with an amazing diversity of plant
species. There are over 4500 vascular and nonvascular (mosses,
lichens) plants within its boundaries. This diversity reflects
the great physical diversity of the state --from sandy beaches
with semi-tropical palms to the highest peaks in the eastern
United States with species more common in northern New York.
Because of this varied geography, North Carolina has more species
of plants than 44 other states, and more than all of Canada.
Some of this plant diversity is in jeopardy. Development on
barrier islands has reduced dune and maritime forest plant
communities. Long-leaf pine forests, once covering the majority
of the coastal plain, now occupy less than 6, of their original
range. Prairie-like habitats in the piedmont are being
urbanized. Second-home development is threatening our rarest
wetland habitats in the mountains.
The need and importance of protecting these imperiled plant
species was recognized by the North Carolina General Assembly by
passage of the Plant Protection and Conservation Act in 1979. To
protect these diminishing species the Act established the Plant
Conservation Program and the Plant Conservation Board and
Scientific Committee.
While there are many components to the protection of rare
plant species, the first step is the determination of those which
are most endangered in the state. The current list contains 102
plant species that are listed as Endangered or Threatened and
another 174 plant species that are candidates for listing.
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EFFORTS TO PROTECT ENDANGERED AND THREATENED PLANT SPECIES: TWO COMPLEMENTARY PROGRAMS --ONE SHARED PURPOSE
The inventory and protection of North Carolina's rarest plant species is the responsibility of two state agencies: the Plant conservation Program in the Plant Industry Division, North Carolina Department of Agriculture, and the Natural Heritage Program in the Division of Parks and Recreation, Department of Environment,_ Health and Natural Resources.
The Plant Conservation Program is the primary agency responsible for the listing and protection of North Carolina's endangered and threatened plant species. It was established by passage of the Plant Protection and Conservation Act in 1979. The program inventories the state's rarest plant species, maintains the list of Endangered, Threatened, Special Concern and Candidate plant species, enforces regulations concerning state-listed plant species (outlined below>, monitors and manages populations of listed species, and provides educational materials to the public. The Act also established the Plant Conservation Board, a regulatory board representing botanical, horticultural, conservation, forestry, and agricultural interests, and the Plant Conservation Scientific Committee, an advisory group to the Board and the Program._
The Natural Heritage Program inventories the state's elements of natural diversity and protects natural areas. The program maintains a data-base of occurrences of rare plants, animals, natural communities, and geologic features, reviews environmental impact reports, inventories rare plant and animal species and exemplary natural communities, and works closely with landowners and governmental agencies to protect populations of rare species and unique natural communities.
Information on state-listed species is maintained in the Natural Heritage Program Inventory, a cross-referenced system of mapped occurrences, manual files, and a computer data-base. All information gathered by researchers and staff of both programs is stored in the Inventory. Information from this Inventory is available for use in environmental impact evaluation, resource management planning, and selected research projects.
These two state agencies work closely with the U.S. Fish and Wildlife Service, U.S. Forest Service, National Park Service, State Parks, N.C. Wildlife Resources Commission, N.C. Department of Transportation, N.C. Botanical Garden, and the North Carolina Nature Conservancy.
The two programs complement one another as they work toward one goal: the protection of North Carolina's biological diversity.
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LIST OP NORTH CAROLINA'S
ENDANGERED, THREATENED AND CANDIDATE PLANT SPECIES
.The following list identifies the native plants of North
Carolina which have been determined to be Endangered, Threatened,
or candidates for Endangered or Threatened status. The list is
the product of research conducted oy the Plant Conservation
Program, Natural Heritage Program, and botanists and naturalists
throughout the state. The species listed as Endangered or
Threatened have been approved by the Plant Conservation
Scientific Committee and the Plant Conservation Board with final
approval by public hearing.
NORTH CAROLINA STATUS: Three categories have been established to
summarize the current biological status of North Carolina's
rarest plant species. These categories rank the species by the
degree to which their survival is jeopardized.
ENDANGERED (El: The most critically imperiled species,
those that may become extinct or disappear from a significant
part of their range if they are not immediately protected.
THREATENED (Tl: The next most critical level of imperiled
species, those that may become endangered in or disappear from
the state if they are not protected.
CANDIDATE (Cl: Species that are under review for listing as
endangered or threatened because of few populations, small
populations, or occurrence in a rare and threatened habitat.
FEDERAL STATUS: Also included in the list is the federal status
of these state-listed species. The status of these species is
determined by the U.S. Fish and Wildlife Service. There are
several categories for federally listed and proposed species.
ENDANGERED (El: The most critically threatened species,
those that may become extinct or disappear from a significant
part of its range if they are not immediately protected.
THREATENED (Tl: The next most critical level of threatened
species, those that may become endangered if they are not
protected.
PE or PT: Candidate species currently proposed for listing
as Endangered or Threatened.
C1: Candidate species presently under review for federal
listing for which adequate information exists on biological
vulnerability and threat(s) to list the taxa as Endangered or
Threatened.
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Cl: Candidate species presently under review for federal
listing for which information indicates that listing as
Endangered or Threatened is possibly appropriate, but for which
adequate data on biological vulnerability and threat(s) are not
currently known or on file to support proposed rules.
REGION IN THE STATE: The regions of the state in which
populations of the listed species are found are: mountains (MT),
piedmont (PDI ,--sandhills (SDI, and coastal plain (CPI. North (n)
and south (s), and for the coastal plain, inner (il and outer
(ol, are added to provide more detailed locational data. For
more information on species in a particular region or county
contact the Natural Heritage Program.
There are a few other abbreviations found in the species
list. They are: SP. for species, SSP. for subspecies, VAR. for
variety, and NOV. for novum, Latin for new.
All endangered and threatened species lists are dynamic,
changing as new data becomes available and protection activities
are implemented. We invite comments on these listed species or
other species appropriate for listing. The comprehensive
information we have on these species was gathered by a
cooperative effort of naturalists, botanists, and
conservationists. Similarly, the protection of these species can
be accomplished only through the cooperative effort of
landowners, federal and state agencies, conservation groups and
concerned individuals.·
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Ciiiiiia iiiiil iiiii iiiii - - - ----.. -------
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I LIST. OF ENOAHGEREO, THREATENED A,10 CANOIOATE PUNT SPECIES
NOii™ CAAOI.INA PUNT OJjSER'/ATl0N P~
FEBRUAAY 1990
I SCIENTIFIC NAl<E CX)tQj -NC FEDERAL ,EGION
surus snrus IN STATE
I ACON!Tl.l< RECLINATI.I< TRAILING loOl.fSBAHE C ,.,.
AO(A)ITl.f' CAPILLUScVENERIS VE!lJS'S-HAIR FERN C sCP
AESOffNCKNE VIRGINICA SENSITIVE J0l"1VITOi E CP
AGAl.!N!S APHYLL.A SCAI.E·LEAF GER.lllOIA C ,CP
I AGAl.!N!S V!RGATA VIRGATE GERAROIA C CP
AGROSTIS MERTENS!! ARCTIC BEJITGRASS C ,..,.,.
ALLII.I< OJ'™BERTII STRIP£D G.UlLIC C PO
I AL!lJS VIRIOIS SSP, CRISPA GIIEEN ALDER C ,..,.,.
..-.RANmJS P\l<ILUS ~ -RAIi™ T C2 CP
AIOI-GEORGIANA VAR, CON'1JSA CAAOI. !NA LEAOPUHT C sCP
A/OIPH.l GEORGIANA VAR, <>EOIIG I ANA GEORGIA LEAOPUHT C ,.a, I A/OIPH.l ~RINI! SOfo<ERIN'S LE.ADl'l-'HT C PO
AMPM!CARPU< P\JRSl<l I P\JRSl<'S GOOBER GRASS C CP
ANOROPOGCN IO<RI I BOG BLUESTEl1 C CP
I A,IEIQ<E BERLA)IO!ERI SCl/THERN THIMl!I.EWEED C PO
&RABI~ H!RSUTA VAR, ADPIIESSIPILIS SUNDER ROOtCRESS C PO
ARABIS HISSCIJRIEPISIS H!SSCIJRI ROCXCRESS C sPO
I •RABIS PATENS SPIIEAOING ROO:CRESS C sHT
ARETHUSA BULBOSA B0Q ROSE E ,.,.
ARiSTIOA PALUSTR!S LONGl.£AF THREE--C CP
ASCLEPIAS PEOICELL.ATA STAUED HIUlEED C sCP
I ASCLEP!AS TO'IENTOSA SAHOH!LLS H!LOIEED C SD tCP
ASPI.EN!l.l' HETERORESILIENS CAIIOl.!NA SPUE!W)RT E C2 sCP
ASPLENII.I< MONAHTHES SINGLE-SOIIUS SPLEEl6«lRT E sHT
I ASTER AV!T\JS .lUXAHOER' S ROO: ASTER C Cl sHT
ASTER GEORGIANUS GEORGIA ASTER C PO
ASTER L.AEVIS VAR. CllNCINNUS Sl«lOTl4 BLUE ASTER C PO
ASTER HIRABILIS P!EIMJjT ASTER C PO
I ASTRAGAI.US H!OiAUXI I M!OWIX'S H!l.J(I/ETOi C SD
BACOiARIS Gl.CKRIJLIFLORA A GRCILWOS£L-TREE C oCP
BALOU I NA A TRQP\JRP\JREA IOIE\'tl)19 HE.AO C sCP
I BET\JL.A PAPYRIFERA VAR, COROIFOLIA /1JJITAIN PAP(R BIROi C ,..,.,.
BOTRVO<Il.l< -TIFIDI.I< W™ERY GWEFERN C ,..,.,.
BOTRVO<I~ ONEIOEHSE BWIT-LOBED GRAPf:FERN C ,<T PO
BOTRYOi I~ SIMPLEX LEAST P'IXNoORT C sHT I BRYOCRl.l<IA A)IDERSON!l GORGE '1lSS E sM'T
BUCXLEYA DISTIO<ll'HYLL.A PIRATEBIJ5!< E C2 sM'T
81.KL!A TENAX TOUGI< BUCICTHORN C oCP
I CACALIA RUGELIA IUGEL'S RAQ.ORT T c, sM'T
CACALIA SUAVEOLENS SWEET l.~OIAN PLANTAIN C sMT
CAL.AHAGROST!S C-IINI I CAIN'S REED GlU.SS C Cl ,.,.
I Lll.N1lVILFA BREVIPILIS PINE BARRENS SANOREED E C2 sCP
C..WSSIA SC!LLO!OES SILO HYACINTH r ,<P
CAROAl'IINE C~El'\ATIT!S >OJNTAIN BITTERCRESS C ,.,.
CAROAMINE FL.AGELL!FERA A BITTE,CRESS C . ..r I 'EB 1990
I
I
m
•-SCIENTIFIC NN1E eoto<NM<E NC ,£0£RAL REGION
STArus snrus [N STATE
CARO.,,INE MICRAHTHERA SIIALL-ANTHERED BITTERCRESS E E nPO
m CAREX AENEA FERHALD'S HAY SEDGE E -CAREX BARRATTll BARRATT'S SEDGE E C2 -iC?
CAREX BIL!J,(JREANA BILT!'ll!IE SEDGE C C2 -I CAR EX BUXBAa< l l SUXIIAI.N'S SEDGE C -CAREX CANESCEHS VAR. O!SJUHCTA SILVERY SEDGE C nCP SD CAREX OC<RW< I I OC<RW<' S SEDGE T sCI'
CAREX COLLINS! I COUIHS'S SEDGE C MT PO E CAREX CONJ!OEA CONE-SHAPED SEDGE T -CAREX EX!LIS MEAGER SEDGE C so CAREX IMPt!ESSINERVIA A SEDGE C MT
I CAREX LEPTONERVIA FINELY-NEl!\IED SEDGE C MT CAREX MANHART!! -RT'S SEDGE C MT CAREX MISERA wRETO<ED SEDGE T -CAREX OL!GOSPERIIA FEW-SEEDED SEDGE C -I CAREX PEOUHCUUTA LllNGSTALK SEDGE C sl'fT sPO c.lREX PROJECTA SEC<LACE SEDGE C MT sPO CAREX PV•PI.J•IFERA P\.JRP\.E SEDGE E MT
I CAREX •OANEHSIS ROAN SEDGE C Cl -CAREX SO<WEINITZII so..E!NITZ'S SEDGE E sHT CAREX vESTITA CLOTl<EO SEDGE C nPO
I CARY A LACIH IOSA BIG SHELL!IARK H[Cl:ORY C nPO CARYA. MYRISTICAEFOR1'1S M11!1EG HICXORY T sCI' OiASl',ANTH I ll1 N I T [ OU1 A SPANGLEGRASS C sCI' O<ELONE CUTHBERT! I OJTHBERT'S TURTI.EHEAO C MT I CIRSILN CAROLINIANLN CAROLINA THISTI.E C PO CUDILN MAR!SCXllDES TWIG-RUSH C
-Cl' COLLiNSON!A rueEROSA TUIIEROJS HORSEBALM C PO
I COLLINSON!A VERT!CILUTA .HOALED HORSEBALM C sPO CON!OSEL!NLN O<INENSE HEl<l.0::X-PARSLEY C MT COREOPS!S UT!FOL!A BIIOAOLEAF COREOPSIS C C2 -CR!NLN ~RICANLN -•LILY C sCI' I CYPERUS OENTATUS TOOTl<ED•LEAF FLATSEDGE C oCP CYP£ RUS HCllK.H TON I I HOUGHTON' S SW€ET-•uSH C PO CYPt!IPEDILN •EGINAE Sl«MV LADY'S SL!PP£R C sHT
I CYSTOPTERIS TENNESSEENSIS TENNESSEE BUDDERFERN E sCI' DALIBAROA REP£HS R08IN R-Y E MT
DELPHINILN EXALTATUM TALL LARKSP\.JR E HT nPO DESOW'PS!A CESPITOSA SSP. GLAOCA . TUFTED HAIRGRASS C sHT I DESHlOILN OO<IIOLEI.Kl.t4 CREA/'!Y TICK-TREFOIL C PO OESHlOll.N SESSILIFOLILN SESSILE·LEAVEO-BEGG.IR'S-TlCK C PO D!SPORLN MACUUTUM NJOOING MANDARIN C MT I EO<!NACEA L.AEVIGATA $otlOTH CONEFLC\<ER E CZ nPO EO<!NOOC•us NULUS CWA•F 3URHEAO C sCP ELEOO<AR IS E·:;l.J !SETO! :ES KJRSETAIL SPIKERUSH C CP
I E~EOCHARIS HALOPH[LA SALT SP!KERUSH T oCP ELEOO<A• IS ,SEUNOCARPA BUC<F•UIT SP!KERUSH C CP ELEOO<A•IS ROBBINS!! ROBB!NS'S S?[KERUSH C CP ELY1't.JS TRAO<YCAULUS SS?. ".'~ACMYCAULUS SLENDER ""EATGRASS C -I FEB 1990 3
I
• • SCIENTIFIC NNE C(JtOj NNE NC •EOERAL ,EGION • STATUS STATUS i:N STATE
EPILOBil.11 LEPTOPHYLLl.11 NARROWLEAF WILLDof<ERB C -I ERl0CAULON LINElRE LINEAR PIPOOAT E ,MT
ERIOCAULOII PARKER! PARKER'S P!PE\,ORT C C2 ,<?
EUPATORil.11 RESINOSl.11 RESINOJS BONESET E C2 ,CP SO
I EUP!<ORBIA PLRPUREA GI.ADE SPUIIG£ C C2 MT
<ILIPENOULA RUBl!l QUEEN-OF-Tl<E-PRAIRIE C MT
<IMBRIST'ILIS PERPUSILLA HARPER'S FRINGE-RUSH T C1 ,CP
FOTHERGI LLA HAJ0R WITOl-ALOER C MT PO I GAILLARDIA AESTIVALIS INOIAN BLANKET C SD GEHTIAHOPSIS CRINITA FRINGED G<NTIAN E MT
li<\14 ALEPP!Cl.11 YEl.l.()j AVENS C MT
I li<l.11 li<NICUL,lTU• BENT AVENS T C2 -s li<\14 RAO!ATl.11 SPIIEAOING AVENS E PE MT
GLYCERIA NUBIGENA -,oJNTAIN ~ E C1 ,MT
~!TIS NI-TA DWARF POLYPODY FERN E C2 ,MT I GVMO:.ARP!L!1 SP. >«N. AP9Al./.Oi!AN OAK CERN C -GVM«lDER/'!A LlNEARE GIOOE FINGER LIOiEN T MT HELEN!l.11 BREVIFOL!l.11 LITTLELEAF SNEEZEl<EEO C MT PO Cl'
I HELIANT!<EPV< BICKNELLII PLAINS FROST',;EED C MT SELIANTHE"'-'< GEORGI..,.,, ii<ORG!A RCX:KROSE C oCP HEL!ANTl<E"-'< Pl!OPINOUt,o CREEPING FRQST',;EEO C MT PD
I HELIANTl<US GLAUCOPHYLLUS -.,ITELEAF SUNFLMR C C2 MT HELIAN™US SOMINITZII SOMINITZ'S SUNFLMR E c, sPO HELCJilAS BULLATA -PINK T T ,MT
HE\JOiERA LONGIFLOl!l LllNG-FLO<ERED ALL.MROOT C MT.
I HEXAST'IL!S CONTl!ACTA l'QJjTAIN HElRTLEAF E C2 sMT HEXASTVLIS LEl<ISII LEWIS'S HEARTLEAF C C2 nPO 1CP HEXASTVLIS NANIFLORA CWARF-FLMRED HEARTLEAF E T sPO
I HEXASTVLI S RHC1'1l I FORIO IS FRENOi BROAll HEARTLEAF C sMT HIEROCHLOE OOORATA HOLY GRASS C -HCUSTONIA PLRPUREA VAR. >'Ol<TANA l'QJjTA!N BLUET C PE -H1JOSONIA >'ONTANA l'QJjTAIN GOLDEN HEATHER T T "'T I HUPERZIA POl!OPHILA R00C CLUBl1lSS C MT HYORASTIS CANADENSIS GOI.OENSEAL E /ofT nPO HYPERICL!1 AOPRESSl.11 BOG ST. JO<N'S-.oRT C CP
I HYPOXIS SESSILIS SESSILE-FLMRED YELLO< STARGRASS : ,Cl' I LEX A/'1ELANOHER SARVIS HOLLY C C2 ,CP iCP !LEX CCLI.INA LONG-STALKED HOLLY T C2 MT ISOETES PIEl)<QNT-PIEl)<QNT CUILOORT T C2 PD I ISOTRIA MEDEOLOIDES SMALL ,HQRLED POGl)j!A E E sMT PD IVA HICROCEPHALA SIIALL·"EAOED HARSH ELDER C sCP JUNOJS GY...ac:ARPUS SAKED-<RUITEO RUSH C MT I JUNCUS TRIFIOUS SSP. ClROLINIANUS ONE-FLOWERED RUSH E CZ -JUNIPERUS CCHV<IS 'JAR. Cc?RESSA GROUND JGNIPER C PO
OLJ1 ! A C:..:NEA TA ""1[TE ·,.tCKV -Cl sCP SO
I LAOiNOCAULON BEYR I CH [ ANl.11 SOUTHERN BOG-BUTTON C ,CP LEOiEA TORREY! TORREY"S Pl.,,.EEO C sCP SO LIA TR IS HELLER I e.ELLER"S 3LAZrnG S7AR ~ T -s LILAEGPSIS DROLINENSIS DROUNA L[c.AEOPSIS T CZ oCP I FEB 1990 l
I
•
I
SCIENTIFIC NN1IE CCl't(lNNNtE NC >Ell£RAl ,EG!ON
I STATIJS STATIJS rN STATE
LILll.1' GRAY! GRAY'S LILY T C2 -I Lll'OSELLA AUSTRALIS AWl.•LEAF ~CWJAT C oCP
LINOERA MELISSAEFOLIA SOJTI<ERN SPICEBUSH E E ,cP
LINOERA SUllCllR!ACEA BOG SPICEBUSH E C2 so
LOBEL IA BOYKIN! I BOYK!N'S LOBELIA C C2 ,CP
I LOPHIOLA AUREA GOI.OEN-CREST C CP
L YCOPUS COKER l COKER'S BUGI.EW€ED C so
LYS!M,t,O<IA ASPERULAEFOL!A RaJGHSLEAF LOOSESTRIFE E E SO sCP
I LYS!M,t,O<IA FRASER! FRASER'S LOOSESTRIFE E sHT
"-ACBR I DEA CAROi. i N I ANA CAROLINA ~INT C sCP
'1ARSHALLlA GRANDIFLORA LARGE-FLCMREO BARIIAAA' S BUTTONS C C2 KT
ME lANTI< I Lf1 l(JQO l I OZ.UK BUNO<FLCMR C sPD I MENYANTHES TR!FOllATA BI.Cl(BEAN T -MILll.1' EFFUSLt1 MILLET GRASS C sHT
.•It•JARTIA GODFREY! GODFREY'S SANMRT E C2 sCP
I MINUART!A GROENLANOICA GREENlANO SANCWJAT C -.04 !NUAIHIA uNlFLORA SINGLE-FLOWERED SANOWORT E sPO
11'.JNOTROPSIS OOORATA SWEET PINESAP C MT PO
I 11MLENBERGIA GLO<ERATA BRISTLY l'«MlY C KT
~ENBERGIA TORREYANA TORREY'S 11MLY E c, sCP
M'IR!CA GALE SW£ET GALE C sHT
M'IR!OPHVLLLM LAXLM LOOS£ WATER!'11Lf0ll T C2 CP
I M'IR!OPHVLLLM TENELLUM LEAFLESS WATERMILFOll C CP
NARTI<EC I Lf1 AMER I CANU1 BOG ASPHODEL E C2 sHT
SESTRONIA Lf1BELLULA NESTRONIA T C2 PO
I ORBEXILLM "-'CROPHVLLUM BIGI.EAF SOJRFPEA E Cl sPD
ORBEXILLM CINOt!RYCHIS l.NCElEAF SOJRFPEA C KT
;ROOTRIO<Lt1 <EEVERAE KEEVER'S BRISTlE l'OSS E . nPO
OXYPOLIS CANBY! CAHBY' S CQ;BAHE E E •CP I OXYPOLIS TERNATA SAVANNA CCl,;SAHE C CP
>ANtC'J< TENERl.1' SCllTliEASTERN PANIC GRASS C CP
PARNASSIA CAROLINIANA CAROLINA GRASS-OF -PARNASSUS E C2 sCP
I >ARNASS!A GRANOIFOLIA LAIIGE•lEAVEO GRASS-OF-PARNASSUS C KT sCP
PARTI<EN!LM INTEGRIFOLIU/'1 VAR AURl<lJLATLM GlAll€ W!LO QUININE C PO
PARTI<ENILM RAOFORO!l SANllHlLLS WILD QUININE C SD
I PELLAEA SRIGHTIANA WRIGHT'S CL:FF-BRAKE CERN E sPO
PHAC£llA RANUNCIJlACEA BUmROJP PHACEllA C nPO
PHAS(OlUS SlNUATIJS SANOHILLS BEAN C SD
PHEGOPTER!S CONNECTlllS NOIITI<ERN BEECH-FERN C s11T
I •tNGUlOJLA P\.NllA Sl'1AlL BUTTER\,ORT C sCP
PlANTAGO CCROATA HEART-LEAF PlANTAIN E CZ sPO
PLANTAG0 SPARSl>LORA PlNElANO PLANTAIN E sCP
I PLATANTHERA INTEGRA YELlOW FRINGELESS CRO<!O T sCP
>LATANTHERA INTEGRILABIA ""ITE FRINGELESS ORO<IO E C2 sl1T
PL.ATANTHEitl, PE}Ui11JE~A PURPLE F,INGElESS CRO<IO C Kl' nPO
,CA PALUOIGENA BOG BLUEGRASS C -I ,CA SALTUENSIS • BLUE GRASS C sl1T
,OLYGALA HOOKER I HCXJKER'S ~!~OORT C sCP
,OLSGCNELLA ARTIC~L.>TA COAST ~:;.~r.EEO C nCP
I 'EB 1990 ·~
I
I
I
SCIENTIFIC NN€ COtOI NN€ NC FEDERAL •EGION
I STATUS STATUS IN STATE
POLYGON.I< Gl.,lUCU1 SEAIIEACH KNOMEO C oCP
I PORT\JL.ACl SMALL! I SMAI.L' S PORT\JL.ACl E PO
POT..-cJGETON CCNFERVOIOES Cl)jfERVl PONOW£EO C SO nCP
PSILOCARYA SC:RPOIOES LONG-8£AK BALO-S£0GE C sC.O
PTEROGI.OSSASPIS ECRISTATA EULOPHll E C2 ,cP I PTILl~ILt< NOOOSl'1 HAIIPERELLA E E nPO
PYROLA ELLIPT!Cl A SIHNLEAF C ,t<T
PY'l<IOANTl<ERA l!ARBUL.AU VAR. BREVIFOLIA wEW'S PIXIE-KlSS E c, so
I RNlJNQJLUS HEOERACEUS IVY BUTTEROJP C nCP
RHO!l ARISTOSl ._O MEAOQ;-BEAUTY T C2 ,c.o
RIUi MIOWJXII MIOWJX'S SUW: E E PO
I RHYNCH0SP0AA ALl!l -..1TE BEAKR\JSH C -CP
RHYNO«lSPOIIA OECLRRENS OEClJRRENT BEAKR\JSH C ,c.o
RHYIO«lSPOAA OLIGANTl<l FEW-FLMREO BEAKRUSH C sC.O PO
RHYNC>ClSPORA PALL!OA PALE BElKRUSH C c.o
I RHYIO«lSPORA STEl<OPl<YLLA LI mELElF BEA KRUSH C sCP
ROBINIA HISPIOA VAR. FERT!LIS FRUITFUL LOCUST C so
ROBINIA H!SPIOA VAR. <ELSEY! <ELSEY'S BRISTLY LOC\JST C ,xr
I ROBINIA VISCOSA VAR. HARTWIG!! HARTW!G'S Cl.Altfr LOCUST C . ,xr
AU08£CK!A HEL!OPSIOIS SIM-FACING CONEFLO.ER T CZ so
RUELL!A HU1lLUS LCM W!LO-PET\JN!l C PO
SA&\Tll KENHEOYANA P\. YK\JTI< GENT! AN T sCP I SAGERET!A M!NUTIFLOAA ~-FLO.CREO BLCl(Tl<(JRN C sCP
SAGITTAR!l FASCICLL.AU l!I.NO<EO ARRO,HEAO E E ,xr
SARAACENll JONES!l >QljTllN SWf:ET PITOiER PLANT E E ,xr
I SlRRM:EN!A OREOPHIL.A GREEN PITOiER PLANT E E ,xr
SlXIFRAGl CAROl.!NIANA CAROi. INA SlXIFRAG£ C CZ HT
SlXIFRAGl PENSYLVAN!Cl -SlXIFRAG£ C -nPO
I SOH SANORA GLABAA >W.NOl.lA•VINE T nCP
SO<LOTl<E!Mll LANCIFOLIA HlGliLANOS ~ T ,xr
SO<WALBEl AM£RICANA OWFSEEO E C2 ,c.o
SC!RPUS CESPITOSIJS DEE~ IR BULRUSH C HT
I SCIRPUS Fl.ACCIOIFOL!US AEQ.INING BULRUSH C nCP
SCIRPUS LINEAT\JS LINEAR-LEAVED BULRUSH C nPO
SQ.ERll GEORGIANA GEORGIA NUTRUSH C ,c.o
I SCLERll vERTIClLL.ATA SAv.-NUTRUSH C sC.O
SOJTELL.AR!l SlXATIL!S ROOC SICULLCAP C -SEOLt< PUSILLLt< P\.ICX"S ORPINE E C2 sPO
SEOLt< ROS£A ROSEROJT E ,.,.T
I SENECIO M!LLEF0\.11.11 OIVIOEO-LEAF RAGWlRT T sMT
SENECIO PL.ATTENSIS PRAIRIE GAOUNOSEL C HT nPO
SENECIO SO<,/EINITZ,ANUS ~INITZ'S GAOUNOSEL E ,t<T
I SHJRT!A GAL.ACIFOLIA OCONEE 3ELLS E C2 sMT sPO
S!LENE OVUA >OIJNTAIN ClTOiFLY C HT
SILPH!Lt< TEREBINTH!NACEL,., PRAIRIE OOCK C nPO
SISYRINO<Ilt< OICHOTO>t.t, REFLEXED BLUE-EYED G•ASS E sPO I SMILAX BILT1<lREANA BILTl<lRE'S C.,RRIONFLO.ER C sMT PO
SOLi OAGO PLU!"OSA PL~E GCLDESROO C PO
SOLIOAGO PTARMICOICES PRAIRIE GCLOESROO C nPO
I FEB 1990 '1
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SCIENTIFIC NNE COtOI NNE ,«: FE0£RAL QEG!()j
m STAT\JS STAT\JS IN STATE
SOI.IOAGO PULOiRA SAVWU.. GOLOENROO E c, sCP • SOI.IDAGO SP!TH.IMEA BLUE R!OGE ,;QLOENROO E T -SOI.IDAGO VERIIA SPRING-FLCWERING GOLDENROD E C2 CP
SPIRAEA VIRGINl.lNA VIRGINIA SPIRAEA E PT '" SP!RAHTl<ES LACINIATA LACE-LIP LAD!ES'-TAESSES C sCP
I SP!RAHTl<ES LONG!LABR!S Lilllr-LIP LAD!ES'-TRESSES C sCP
SPOIIOBOLUS HETEROLEP!S PRAIRIE DIIOPSEED E sMT
SPOAOBOLUS TERETIFOLIUS W!RELEAF DROPSEEO T C2 sCP
I STREPTOPIJS A/1PLEX!FOL!US WHITE "-'HOAR!N C '" STYllSIIA P!CXERINGII VAR. PICXER!NGII P!CXERING'S IG!H!NG GLORY E C2 SO sCP
SYNAHOAA HISPIOULA SYNAHOAA C C2 sMT
1'l<AI.ICT-CIXlLEYl CIXlL£Y' S '1EAOIWIUE E E sCP I 1'H£LYPTER!S S!IIJLATA BOG FERN T -Tl<ERKlPSIS ><JI.LIS VAR. FIW<!N!FOLIA A.SH-LEAVED GOLDEN--R C so
TOflELDIA GLA8IIA G1.A8RWS FALSE ASPl<OO£L C CP
I Tllf!ELD!A GLUT!NOSA ST!Cl:Y l!0G ASPKlOEL C '" TA!OOW<ES BOSO<!ANl.11 APl'AL.<Oi!AN Fll.1"1-FERN T sMT
TR!OOW<ES PETERS!! OWAaF Fll.1"1-FERN T sMT
TQIOiOSTEIIA SP. QUj[ BLUEQJRLS C sCP I TA!Df:NS CAAOI.IN!ANUS CAIIOI.INA SAN0GRASS C SO sCP
TRIENTALIS l!Ot!EAL!S STAAFLCW:R C sMT
TRILL!Lt1 D!SClll.OR >'llTTl.EO TRILL!Lt1 T sMT
I TRILLILt1 FLEX!PES l!£HT WHITE TRILLILt1 C '" TRILLILt1 PUSILLLJ'1 CAIIOI.INA LEAST TR!LL!Lt1 E C2 CP
TRILLILJ'1 REQJRVATI..N 1'4'A!RIE TRILL1Lt1 C KT
I TRISrn.11 SP!CATI..N VAR. ,0.LE SOFT TR 15£TI..N E -UTRIQJLARIA MINOA USS[R BL.ADOERIOIT C -UTRIQJLAR!A OLIVACEA OWAaF BL.ADOERIOIT T sa>
VACCIN!Lt1 H!RSl/11.N WAIRY BLUEBERRY C sMT
I VACCIN!Lt1 MACIIOCARPON CUN8ERAY C -CP
VERBENA RIPAR!A RIVER VERVA!N C sPO
VERBESINA WALTER! WAI.TEA'S W!NGSTE/1 C •CP
I WAREA CLNIFOL!A CAIIOI.INA WAREA C so
XYRIS FLABELLIFORl11S SAV-YELLCW-EYEO GRASS C sCP
ZIGAllENUS ELEGANS SSP. GL.ALOJS WHITE CNIASS C -I
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Snecial Concern Plant Species
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LIST OF
NORTH CAROLINA'S SPECIAL CONCERN SPECIES
The following list identifies the plant species determined
as Special Concern. Like the list of Endangered and Threatened
plant species, this list is the product of research by the Plant
Conservation Program and review by the Plant Conservation Board
and Scientific Committee. Final approval was by public hearing.
STATE STATUS: Two types of species are listed as Special
Concern, those that are listed as Endangered or Threatened and
those that are not.
ENDANGER.ED -SPECIAL CONCERN (E-SC) and THREATENED -SPECIAL
CONCERN (T-SC): These are species listed as Endangered or
Threatened of which propagated plants may be offered for sale or
exchange. Propagated plants of these species must be offered by
a registered propagator and accompanied by a commerce permit and
tag. It is unlawful to sell, trade, or exchange propagated
plants of species listed as Endangered or Threatened if they are
not also listed as Special Concern. For all species listed as
Endangered or Threatened it is unlawful to sell, trade, or
exchange wild-collected plants.
SPECIAL CONCERN (SC): Species that require monitoring but
may be collected lawfully from the wild and sold according to
specific regulations. Regulations are specific for each species.
Contact the Plant Conservation Program for additional
information.
FEDERAL STATUS: The federal status categories of these species
are described under the list of Endangered, Threatened and
Candidate plant species.
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LIST or SPECIAL CONCERN PLANT SPECIES NORTH CAROLINA PLANT CONSERVATION PROGRAM AUGUST 1990
SCIENTIFIC NAME COMMON NAME
CYSTOPTERIS TENNESSEENSIS TENNESSEE BLADDERFERN DELPHINIUM EXALTATUM TALL LARKSPUR ECHINACEA LAEVIGATA SMOOTH CONEFLOWER GENTIANOPSIS CRINITA FRINGED GENTIAN CEUH RADIATUM SPREADING AVENS HELONIAS BULLATA SWAMP PINK KYDRASTIS CANADENSIS COLDEN SEAL KALKIA CUNEATA WHITE WICKY LIATRIS HELLERI KELLER'S BLAZING STAR LILIUM CRAYI CRAY'S LILY PANAX QUINQUEFOLIUS GINSENG PELLAEA WRIGHTIANA WRICH?' CLIFF-BRAKE FERN RHUS MICHAUXII MICHAUX'S SUMAC SABATIA KENNEDYANA PLYMOUTH GENTIAN, SEA PINK SARRACEHIA JONESII MOUNTAIN SWEET PITCHER PLANT SARRACENIA OREOPHILA GREEN PITCHER PLANT SCHISANDRA GLABRA MAGNOLIA-VINE SHORTIA CALACIFOLIA OCONEE BELLS
NC FEDERAL STATUS STATUS
E·SC
E·SC
E·SC
E·SC C2
E-sc E
T·SC T
E·SC
E-sc Cl T·SC T
T·SC C2
SC
E•SC
E-sc E
T·SC
E·SC E
E·SC E
T·SC
E·SC C2
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liiiiiii liiiiil iiii .. -.. -liliil liiii -.. --------
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REGULATIONS AND PERMITS
Plant species listed as Endangered, Threatened and Special
concern are legally protected. Under the regulations the term
"plant" applies to all parts of the plant, including seeds, roots
and propagules. The following is a brief summary of the .
regulations. For more information contact the Plant Conservation
Program.
ENDANGERED AND THREATENED PLANT SPECIES: For species listed as
Endangered or Threatened it is unlawful to sell, trade, or
exchange for any purpose any wild-collected plant. A permit
system allows individuals to possess legally-obtained Endangered
and Threatened species. There are two types of permits: a
Protected Plant Conservation Permit and a Protected Plant
Propagation Permit.
PROTECTED PLANT CONSERVATION PERMIT: A permit issued to
individuals who possess Endangered or Threatened plants which
have been legally obtained. Conservation permits may be obtained
for any listed species if possession is intended to enhance the
survival of the species. This includes scientific research on
the biology of the species, rescue operations to save the plants
from destruction, and cultivation of plants by home gardeners.
PROTECTED PLANT PROPAGATION PERMIT: A permit issued to
nurseries that wish to sell propagated plants of Endangered-
Special Concern and Threatened-Special Concern status. Plants
that are sold, exchanged, traded or otherwise moved must be
accompanied by a commerce permit and tags.
To collect plants of Endangered or Threatened species from
the wild requires written permission of the landowner and a
permit from the Plant Conservation Program. Collection from the
wild is approved only for specific reasons that would enhance the
survival of the species.
SPECIAL CONCERN PLANT SPECIES: For species listed as Special
Concern, the collection from the wild and sale of wild-collected
plants is regulated. Contact the Plant Conservation Program for
additional information.
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NEW HANOVER COUNTY PROTECTED SPECIES LIST
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SC
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SC
SC
SC
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SC
SC
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SC
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SC
SC
SC
SC
SC
~ N.C. :.;[L.D.,[FE ~ 70 9'31349.!5619 P.04
NEW MANOUER C~NTY
PROTECTED SPEC:ES .LlST
CQ!'MQN NA1'11; ·
PEREGRINE FALCON RiO-COCKAOED WOODPECKER SHORTNOSE STURGEON RIDLEY
.. PlPlNG PLOVER
EJ:ISTERN WOODRAT LOGGERHEAD
GREEN TURTLE AMERICAN ALLIGATOR CRAWFtSH FROG BROWN PELICAN
SNOWY EGRIT
LlTTut BLUE MEACN TRICOLORED MERON GLOSSV rats
BLACK UUL TURE
COOPER'S MAWK GULL-BILLED TERN BLACK SKIMM&:R
NORTHERN SAW-WHET OWL GOI..DEN-CROWN&:ll KINGLET LOGGERHEAD SHRIKE SACHMAN1 S SPARROW
STQR-NOSED 1'10LE SOUTHEJ:ISTERN 1'1YOTIS RAFINESCUE'S SIG-EARED. BAT BRQZILIAN FREE-TAILED BAT DIAMONDBACK TERRAPIN MIMIC GLASS LIZARD PINE SNAKE
SCIENTtFIC '-lAl'1E
FALCO P&:REGR!NUS
PICOIDES BOREALIS
ACIPENSER BREVIROSTRUM LEPIDOCHELYS KEl'IPII CHARQDRIUS Ml!I..OCUS NiOTOMA FLORIDANA FLORIDANA CQAETTA CQRETTA
CHELONlA MYDAS ALLIGATOR MISSISSlPPtENSIS RANA QREOLATA
PELECANUS OCCIDENTALIS
EGRETTA THIJl..i:I
EGRETTA CQERLILEA
EGRETTQ TRICOLOR PLEGACIS FALCINELLUS CORAGVPS ATRATUS ACCIPITI.R COOPERII
STERNA NILOTICA
RVNCHOPS NIGER AEGOLIUS QCADIC1.JS REGuLUS SATRAPA
LANIUS LUDOVlCIANUS
AIMOPHILA AESTIVALIS CONDvt.URA CRISTATQ MYOTIS AUSTRORIPARIUS
PLECOTUS RAF!NaSQUII TACAR[CA BAASILIENSIS MALACLEMYS TERRAPIN
OPHISAUAUS M!MICUS PtTUOPHIS MELANOLEUCUS
TOTl'L P.04
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NORTH CAROLINA HERITAGE PROGRAM
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EXPLANATION OF SPECIES STATUS CODES
The attached output from the N.C. Natural Heritage Program
database is a listing of the elements (rare species, geolog:c
f eat.ures, natural communities, special animal habitats) kno·..in to
occur in your geographic area of interest.. Following is an
explanat.ion of the four columns of status codes on the right.hand
side of the-printout.
STATE STATUS
Plants:
E = Endangered
T = Threatened
SC= Special Concern
C = Candidate
SR= Significantly Rare
From most recent Natural Heritage Program and Plant
Conservation Program lists.
E,T,and SC species are prot.ected by stat.e law (the Plant Protec-
tion and Conservar.ion Act, 1979); t.he or.her two categories
indicate rarity and the need for population monitoring and
conservation action, as determined by the Plant Conservat.ion and
Natural Heritage Programs.
Animals:
E = Endangered
T = Threatened
SR= Significantly Rare
P_ = Proposed (E,T, or SC)
SC= Special Concern
UNK= Under.ermined
EX= Extir;iated
The Endangered, Threatened, and Special Concern statuses
for Vertebrates and Mollusks are from "Endangered Wildlife of
North Carolina", June 13, 1990, N.C. Nongame and Endangered
Wildlife Program. As of that date, Mammals, Birds, Rept.iles, and
Amphibians have legally protected State status,· ·..ihereas lists for
Fishes and Mollusks have not yet been adopt.ed for legal
protection. Stat.uses for invertebrates other than mollusks and
butterflies are primarily taken frorri Cooper, J.E., S.S. Robinson,
and J.B. Funderburg (Eds.). 1977. Endangered and Threatened
Plants and Animals of North Carolina. N. C. :.iuseu.'n of Natural
History, Raleigh, NC. 444 pages+ i-xvi. 7he Significantly Rare,
Undetermined, and Extirpated statuses are (for -che most. part)
Natural Heri -cage ?rogram designat.ions.. They indicat.e rar i -c·1 and
the need for population monit.oring and conservation action.
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FEDERAL STATUS
From Endangered & Threatened Wildlife and Plants, April 10,
1987. 50 CFR 17.11 & 17.12. Department of Interior. Established
by the Endangered Species Act of 1973, as amended.
E = Taxa currently listed as Endangered
T = Taxa currently listed as Threatened
PE= Taxa currently proposed for listing as Endangered
PT= Taxa currently proposed for listing as Threatened
Taxa·under review for possible listing ("candidate species"):
Cl= Taxa with sufficient information to support listing
C2 = Taxa without sufficient information to support listing
GLOBAL RANK (STATE RANK)
The Nature Conservancy's system of measuring rarity and
threat status. "Global" refers to worldwide, "State" to
statewide.
Gl = Critically imperiled globally because of extreme rarity
or otherwise very vulnerable to exinction throughout
its range.
G2 = Imperiled globally because of rarity or otherwise
vulnerable to extinction throughout its range.
G3 = Either very rare and local throughout its range, or
found locally in a restricted area.
G4 = Apparently secure globally, though it may be quite rare
in parts of its range (especially at the periphery).
GS= Demonstrably secure globally, though it may be quite
rare in parts of its range (especially at the periphery).
GU= Possibly in peril but status uncertain; need more
information.
GX = Believed to be extinct throughout range.
Q = a suffix attached to the Global Rank indicating questionable
taxonomic status.
T = an additional status for the subspecies or variety; the
G rank then refers only to the species as a whole.
State rank codes follow the same definitions, except substitute
the words, "in the state," for "globally" or "throughout its
range."
9/18/90
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zN.C. ~ATURAL ~ERITAGE =ROGRAM AND PLANT CONSERVATI:N ~ROGRAM E~EMENT L:STz
U SCIENTIFIC AND
COMMON NAME
*** vascwlar olants I AGALINIS ARHYLLA
SCALE-LEAF GERARDIA
AGALINIS LINIFOL:A
IJ FLAXLEAF GERARDIA II AGALINIS VIRGATA
BRANCHED GERARDIA II AMARANTHUS PUMILUS II SEABEACH AMARANTH
AMORPHA GEORGIANA VAR C:NFUSA
SAVANNA LEADPLANT I ARISTIDA PALUSTRIS
LONGLEAF THREE-AWN
ASCLEP!AS PEDICELLATA
I SAVANNA M!LKWEEO
ASTRAGALUS M!CHAUXII
SANDHILLS MILKVETCH
I BACOPA INNOMINATA
A WATER-HYSSOP
CAREX CHAPMANII
CHAPMAN'S SEDGE
I CAREX DECOMPOSITA
CYPRESS KNEE SEDGE
CAREX VERRUCOSA
WARTY SEDGE I CRINUM AMERICANUM
SWAMP-LILY
CYPERUS LECONTE!
I LECONTE'S FLATSEDGE
CYPERUS TETRAGCNUS
FOUR-ANGLEcl Fc.'ATSEDGE
I DIONAEA MUSCI;>ULA
VENUS FLYTRAP
ELEOCHARIS EQUISETO!DES
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HORSETAIL SPIKERUSH
ELEOCHARIS MELANOCARPA
BLACKFRUIT SPIKERUSH
ELEOCHARIS ROBBINS!!
ROBBINS'S SPIKERUSH
ERYTHRINA HERBACEA
C.<>RAL-~E.I'""
EUPATORIUM LEPTOPHYLLUM
LIMESINK DOG-FENNEL I HE'-'.·:ruM PINNAT:.~::::uM
DISSECTED SNEEZEWEED I ~YPERICUM AOPRESSUM
:OG ST. :OHN'S-WORT
LACHNOCAULON 8EYRICH!ANUM I SOUTHERN 80G-8UTTCN
'.TIAFOPS!S CAROL!NENSIS
STATE USA STATE GLOBAL
PROT. RROT. RANK RANK
C
SR
C
T
C
C
C
C
SR
T
SR
SR
C
SR
SR
C
SR
C
C
SR
C
SR
C
C
T
SR
C2
C2
C2
C2
3C
3C
3C
3C
S2
S2
S2
52
Sl
S2
Sl
SH
Sl
SH
Sl
Sl
SH
S2
S3
S2
Sl?
Sl
Sl
Sl
S2?
SH
Sl
52
52
G3G4
G3G4
G3G4
G2
G2Tl
G4
G3G4
G3
GS
G2G3
G3G4
GS
GS
G4?
G4?
G3
G4
G4
G4GS
GS
G4GS
G3GS
G2G3
G2G3
G3
G4
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ZN.C. NATURAL HER:7AGE =RCGRAM ANO PLANT CCNSERVA7!CN CROGRAM ELEMENT L:srz
Ill SCIENTIFIC ANO II COMMori NAME
111 SOUTHERN TWAYBLADE
IJ LITSEA AEST:VALIS
PONDSPICE
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LOPHIOLA AUREA
GOLDEN CRES.T
LUOWIGIA ALATA
WINGED SEEDBOX
I) LUDWIGIA LANCEOLATA
II LANCELEAF SEEDBOX
LUDWIGIA LINIFOLIA
FLAXLEAF SEEDBOX I LUDWIGIA SUFFRUTICOSA
SHRUBBY SEEDBOX
PANICUM TENERUM
I SOUTHEASTERN PANIC GRASS
PELTANDRA SAGITTIFOLI.:.
SPOON FLOWER
I PLATANTHERA NIVEA
SNOWY ORCHID
POLYGALA HOOKER!
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HOOKER'S MILKWORT
POLYGONUM GLAUCUM
SEA8EACH KNOTWEED
PTEROGLOSSASPIS ECRISTATA
EULOPH IA
PTILIMN!UM COSTATIJM
RI98ED BISHOP'S-WEED
RHEXIA CUBENSIS
CUBAN MEADOW-BEAUTY
RHYNCHOSPORA PALL!OA
.CALE SEAKRUSH
RHYNCHOSPORA PLE!ANTHA
COASTAL BEAKRUSH
RHYNCHOSPORA SC!RPOIDES
LONG-BEAK BALO-SEDGE
RHYNCHOSPORA TRACY!
TRACY'S BEAKRUSH
SCLERIA GEORGIANA
GEORGIA NUTRUSH
SIDEROXYLON TENAX
TOUGH 8UMELIA
SOL!OAGO VERNA
SPR!NG-FLOWER!NG
STYL!SMA PICKERING:: VAR =:cKER!NGI:
PICKERING'S MORNI:JG GLCRY
THAL!CTRUM COOLEY!
COOLEY'S MEADOWRUE
TOF!ELC:A GLABRA
CAPOL :t1A ASPHODEL
STATE USA STATE GLOBAL
PROT. PROT. RANK RANK
C
C
SR
SR
SR
SR
SR
SR
C
C
C
E
SR
SR
SR
C
C
SR
C
C
E
E
E
C
C
C2
C2
C2
CZ
C2
C2
S2 G4GS
Sl G4
S2? G3G4
SH G?
Sl G4
S2 GS
Sl G4
S2 G3G4
S2 GS
Sl? G3G4
Sl G3
SX G3G4
Sl GS
Sl G4GS
S2S3 G2G3
Sl G3
Sl G4
S2 G4
Sl G4
Sl G3?
52 G2?
SZ
Sl
S2S3
S2
S2
G4?Tl?
Gl
G2G3
G2
G4
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APPENDIX D
SAMPLE CALCULATION FOR ESTIMATING
THE EXPOSURE POINT CONCENTRATION
NHAN009.023
: :_·' ~·:~•~~~~•~: :i ~· · .. ~-· :c-'.·~· ,. ~~~'--'----'~
. ,. :-, • • , -_.J: ,. •• " .!; : __ . '. ' '. . . .. i1'·'_; ·•c.DM.· ··-F:ED-ER'A.L: ~:RoiQRt\,i,\s·· -. c,:o R r o R AT i oN. i' • .
II .. · se~ter!iber2s)1992· .. , .:,·_
• ·, ~ I • , •
1.
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.· ·¥/·,Jon Born~plm :· . . ... ·-. _ _ . · u,s: Environrrierital Protection Agency .
. 345 Courtland Street N:E. ; · . ' . . . ·, _.,,· ; . _._. ·. . . '._ . . ,·•. · ..
· Atlanta; Georgia 30365, '· . . . ' . ' . . . ·. \.
· · Subject: · '.New;Hanciver.County Airport Burn Pit Site
Wilmingtori;c,North'.Car.dlina : < .·. ·.·. 0\' •..
: ·;_.
. _ Project: ' . . . . : EPA Contract No. :68: W9-0()56 ' ..• . . .· -, ., '. ..,; -./' •,
· ~oc~mept Control N~::· .. ·•: 7740~005:RA-BGVQ · , : . : . ~ ' -., ---~'. ' . , _,
DeiirMr. Bornholin: : •. ;. .
. ;_'(,• ..
. Iri response to the'fa:x received ~n Septemb,er 14; '.1992, Camp Dresser cSl McKee Federal ·.· ,•
· · Prngrains Corporation (CDM Federal) is-sub1Tiitting the following.sample_ data set, equation, .
and sample calculation to derive ihe)5 perceilt upper. ~onfidence liinit. .The applied statistics · ..
are:rev1sed'io be in agreement with the information obtained frilm the March 26, 1991 Region>.
IV Supplementa!•Risk'Assessment Guidapce provided by Ms.Julie °Keller·(EPA) .. '.., . ·. . :."~·<:--· . . .. -.. ~:-__ ; -.. ··" ' . . -.
Attachinent1 ;pi-eserii~ the d~t(setfor' Qenzene:, Attachment 2 is the equatidn to calculate the
. 95 peibenltipper confidencb;Iimit from the .data' set:. i11;additi.oii, Attacliment 3 is a table • .. ·
·· pro\iided_ tc{derive.the Hvalue necessary t6ca!tulate the exposure point'concentraiion. • . ·. . ~: ~ . . . . . . . .. ·. . ! ... • .. '. ' .... ' ' . .. . . . . . . . . . . -'. . . . . , .. ,.
I hope the·information prpvi<led is-ad~u:i.te. _We apprecjate the opportunity to be of continued
assistance ro EPA.on this.project.· . . :· :· . .·-. . · ·.
< • • •• • ', •• -...
''
Sincerely, ·:\, ,--·:. ,,._: ..
CDM. Federa.l Programs qorporation
• •·R----~¼ ~, :~Jt.~r-
Gary.r::. 'demons, l'h:D., P:E. . ..
GLC/pw .·
; '
A ttachlnents .
cc: Mary K. Leslie, COM FederaliOKR • ..
Document,Confrol. ·
2030 Powers Ferry Road, Suite 499 Atl~nta, GA 30339 404 952-7393
LTR0JI.022
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ATIACHMENf 1 E DATA SET FOR BENZENE
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I 110 4.7
I 0.5 ND -0.7
110 4.7
I 7.9 J 2.1
3.5 I 1.3
I 0.5 ND -0.7
7.7 2.0
I 0.5 ND -0.7
1.1 0.1
94 4.5
I 0.5 ND -0.7
31 3.4
I 7.7 2.0
74 4.3
I 110 4.7
0.5 ND -0.7
I 0.5ND -0.7
0.5 ND -0.7
I 4.2 1.4
0.5 ND -0.7
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ATTACHMENT 2
To calculate the 95 percent upper confidence limit (UCL) the following equation is used:
UCL =
where:
X =
s =
H =
n =
e =
UCL =
e
[ x + o.5 s2 + ,ill v n-1 )
mean of the log transformed data = 1.5
standard deviation of the log transformed data = 2.2
statistic (from Attachment 3) = 4.141
sample size = 20
constant (natural log)
95th upper confidence limit on the arithmetic mean
The H statistic is found by using the standard deviation and the sample size for the data set
and obtaining the value from the one-sided upper 95% confidence limit table (Attachment 3).
The antilog of the resultant sum is the exposure point concentration.
For example,
1.5 + [0.5 * 2.22] + [ 2.2 * 4.141
Vl9
The exposure point concentration = e 6·01 = 407 µg/1.
) = 6.01
Since the 95 % UCL value exceeds the maximum detected concentration for this data set, the
maximum detected concentration of 110 µg/1 is used to estimate risk for benzene.
LTR03I.022
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Table A12
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0.10
0.20
0.30 o.,o
o.so
0.60
0.70
0.10
0.90
1 .00
1 .2S
1 .50
1.75
2.00
2 .so
3 .00
3.50
•. 00
,.so
5.00
6.00
7.00
8.00
9.00
10.00
ATIACHMENT 3
Values of H, _ 0 = H0 95 for Computing a One-Sided Upper 95% Confidence Limit
on a Lognormal Mean
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3 s 7 10 12 15 21 31 SI 101
Z.750 2.035 1.116 1.102 1.775 1.7'9 1 .7Z2 1. 701 1.68• 1.670 3.295 2.1'8 1.992 , .1e, 1 .1•3 1.809 , .n, 1. 7•2 1 .711 1 .697 ,.,o9 2.,02 2.125 1.977 1.92:' , .ao~ 1 .133 1 .793 1. 761 1 .733 S .220 2.651 2 .212 2.089 2.026 1 .968 1 .905 1.156 1 .11) 1 .777 ,.,95 2.9'7 2 .&65 2.220 2. ,,, 2 .068 1.959 1.928 1.1~6 1.130
7.807 3 .287 2.673 2 .368 2.271 2. 181 :.oe~ 2.010 1 .916 · 1 • 891 9. 120 3.662 2.9011 2.537 2.411' 2 .306 2.191 2.102 .2.0.s 1 .960 10.•3 •.062 3.1S5 2.710 2.570 2.,.3 2.307 2.202 2 .112 2.035 11 .H ,.,i8 3.&20 2 .90: 2.738 2.5e9 2.•32 2 .310 2.206 2 .117 13.05 •.905 3.696 3. 103 2.915 2.7U 2.5 .. 2.•23 2 .3()1; 2.20S
16.33 6.001 ••• 26 3.639 l.389 3 .163 2 .923 2.737 2 .!>IO 2.417 19.60 7 .120 s. ,e, •.207 3.196 3.612 l .311 l.077 2.111 2. 713 22.87 1.250 S.960 •.795 • .,22 •.oe1 3.719 l.'37 l.200 2.997 26. ~ -9.387 6.7'7 5.396 &.962 •. s .. ". ,., l.812 3.Sll 3.295 3 2. 69 11 .67 1.339 6.621 6.067 S.557 S .013 •.see ,.211 3.920
39.23 13.97 9 .9•s 7.16• 7 .191 6.570 5.907 S.38e •.9'7 •.S69 •S.77 16.27 11.S6 9.11 e 1.326 7.596 6.815 6.201 S.681 5.233 52.31 18.58 13. 18 10.38 9.•69 8.630 7 .731 7.02• 6.112, 5.906 58.85 20.88 1' .80 11 .,. 10.62 9.669 8.&52 7 .8>4 7. 1 ,, 6.S90 65 .35 23.19 16.•3 12.91 11. 77 10.71 9.579 8.688 7 .92' 1.2n
78.•7 27.81 19.68 15.•S H.011 1 2. a 1 11.u 10.36 , ... , 8.661 91.S5 32.•3 22.9• 18.00 16.39 1' .90 13.31 12.os 10.98 10.0S 10< .6 37 .06 26.20 20.SS 18. 71 17 .01 15.18 13. 7' 12.51 11 .•5 117 .7 ,1.68 29.16 23 .10 21.03 19. 11 17.0S 15.'3 1'.05 12.15 130.8 '6.31 32.73 25.66 23.35 21.22 11.93 17 .13 1S.59 1'.26
Source: After Land. 1975.
LTROJ! .022