12-012 Code Vt. R. 12-032-012-X

Current through August, 2024

Section 12 032 012 - VERMONT GROUNDWATER PROTECTION RULE AND STRATEGY

Appendix D Hazardous Materials Listing

Pursuant to 10 V.S.A. § 6602(16)(A)(iv) any chemical or substance listed in the following table is a hazardous material.

CAS Number	Chemical Name
335-67-1	perfluorooctanic acid (PFOA)
1763-23-1	perfluoro-octane sulfonic acid (PFOS)
355-46-4	perfluorohexane sulfonic acid (PFHxS)
375-85-9	perfluoroheptanoic acid (PFHpA)
375-95-1	perfluorononanoic acid (PFNA)

Section D1 HAZARDOUS MATERIALS LISTING

Pursuant to 10 V.S.A. § 6602(16)(A)(iv) any chemical or substance listed in the following table is a hazardous material.

CAS Number	Chemical Name
335-67-1	perfluorooctanic acid (PFOA)
1763-23-1	perfluoro-octane sulfonic acid (PFOS)
355-46-4	perfluorohexane sulfonic acid (PFHxS)
375-85-9	perfluoroheptanoic acid (PFHpA)
375-95-1	perfluorononanoic acid (PFNA)

Appendix E Cumulative Risk Assessments

Nota bene: risk-based concentration (rbc) means the calculated concentration of a chemical (or group of chemicals) in an environmental medium estimated to correspond to a fixed level of risk e.g., a target Hazard Quotient (THQ) of 1.0 for noncarcinogenic (systemic, threshold) effects or target incremental lifetime cancer risk (ILCR) of one-in-one-million (1x10 [-6) ], for a predefined hypothetical human exposure scenario. Examples of rbcs for different environmental media based on different hypothetical exposure scenarios are included in this appendix as Tables 1-3.

I. SAMPLE-WISE APPROACH

For each Hypothetical Human Receptor Scenario and exposure medium (i.e., Soil, Indoor Air):

1. In accordance with the IRULE, for each sample, identify chemicals that are present above detection and retained for further consideration.

2. For each chemical, identify and record its receptor and medium-specific cancer and noncancer risk-based concentration (rbc) if both are available. Segregate cancer (c) from noncancer (nc) rbcs.

3. For each carcinogen in a sample, calculate the associated Incremental Lifetime Cancer Risk (ILCR):

a. Calculate the ILCR associated with each individual chemical that has a cancer rbc:

For a given chemical i in sample j:

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b. Calculate the cumulative ILCR across all chemicals in a sample that have a cancer rbc:

For a given number of chemicals (n) in sample j, where i is the first chemical:

Click here to view image

4. For each noncarcinogen in a sample, calculate the associated Hazard Quotient (HQ):

a. Calculate the HQ associated with each individual chemical that has a noncancer rbc:

For given a chemical i in sample j:

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b. Calculate the Hazard Index (sum of HQs) across all chemicals in a sample that have a noncancer rbc. Do not segregate chemicals by critical effect.

For a given number of chemicals (n) in sample j, where i is the first chemical:

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Example Sample-wise Calculation for Direct Contact to Soil: Residential Scenario

1. Benzene and ethylbenzene are detected in Soil Sample S01 at the following concentrations

Analyte	Soil Sample S01 (mg/kg)
Benzene	4.00E-01
Ethylbenzene	6.00E+00

2. Use Table 1 to find Residential Soil cancer and noncancer rbcs for benzene and ethylbenzene:

Analyte	Sample Concentration Soil Sample S01 (mg/kg)	Resident - Soil rbcs from Table 1
		rbccancer * (mg/kg)	rbcnoncancer * (mg/kg)
Benzene	4.00E-01	6.98E-01	1.11E+02
Ethylbenzene	6.00E+00	3.68E+00	4.45E+02

[*] Cancer rbcs are based on target ILCR=1E [-06; ] noncancer rbcs are based on target HQ=1.0

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7. It may be helpful to consolidate all this information into a table such as the following:

Resident - Soil
CANCER		NONCANCER
Analyte	Site Concentration Sample S01 (mg/kg)	a rbccancer (mg/kg)	Sample S01 ILCR (unitless)	b rbcnoncancer (mg/kg)	Sample S01 HQ (unitless)
Benzene	4.00E-01	6.98E-01	5.73E-07	1.11E+02	3.60E-02
Ethylbenzene	2.00E+00	3.68E+00	1.63E-06	4.45E+02	1.35E-02
Sample S01 Cumulative ILCR =	2.20E-06	Sample S01 Hazard Index =	4.95E-01

a. Cancer rbcs are based on a target Risk of 1E [-06 ]

b. Noncancer rbcs are based on a target Hazard Quotient of 1.0

8. The Cumulative ILCR and HI can now be compared to the target ILCR and target HI to determine whether further action is warranted:

a. Is the cumulative ILCR > the target cancer risk?

Is 2.20E [-06 ]>1E [-06 ]?

Yes

b. Is the HI > the target HI?

Is 4.59E [-01 ]>1

No

c. Because the Cumulative ILCR is greater than the target ILCR for the site, further attention is warranted.

II. SITE-WIDE/EXPOSURE UNIT APPROACH: Summary Statistic used as Exposure Point Concentration

For each Hypothetical Human Receptor Scenario and exposure medium (i.e., Soil, Indoor Air):

1. In accordance with the IRULE, for each site, or each exposure unit if appropriate, identify chemicals that are present above detection and retained for further consideration

2. Use appropriate Summary Statistic to develop chemical-specific Exposure Point Concentrations (EPCs).

3. For each chemical, identify and record its receptor and medium-specific cancer and noncancer risk-based concentration (rbc), if both are available. Segregate cancer (c) from noncancer (nc) rbcs.

4. For each carcinogen, calculate the associated Site Incremental Lifetime Cancer Risk (ILCR):

a. Calculate the ILCR associated with each individual chemical that has a cancer rbc:

For given chemical i:

Click here to view image

b. Calculate the cumulative Site ILCR across all the chemicals that have a cancer rbc:

For a given number of chemicals ( n), where i is the first chemical:

Click here to view image

5. For each noncarcinogen, calculate the associated Site Hazard Quotient (HQ):

a. Calculate the HQ associated with each individual chemical that has a noncancer rbc:

For given chemical i:

Click here to view image

b. Calculate the Hazard Index (sum of HQs) across all chemicals that have a noncancer rbc. Do not segregate chemicals by critical effect.:

For a given number of chemicals ( n), where i is the first chemical:

Click here to view image

Example Site-wide Calculation for Direct Contact to Soil: Residential Scenario

1. Benzene and ethylbenzene are detected in soil. The following Site-wide Exposure Point Concentrations (EPCs) are determined:

Analyte	Soil Exposure Point Concentration (mg/kg)
Benzene	4.00E-01
Ethylbenzene	6.00E+00

2. Use Table 1 to find Residential Soil cancer and noncancer rbcs for Benzene and Ethylbenzene:

Resident - Soil rbcs from Table 1
Analyte	Soil Concentration (mg/kg)	rbccancer* (mg/kg)	rbcnoncancer* (mg/kg)
Benzene	4.00E-01	6.98E-01	1.11E+02
Ethylbenzene	6.00E+00	3.68E+00	4.45E+02

[* ] Cancer rbcs are based on a target ICLR=1E [-06; ] noncancer rbcs are based on target HQ=1.0

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7. It may be helpful to consolidate all this information into a table such as the following:

Resident - Soil
CANCER		NONCANCER
Analyte	Site Exposure Point Concentration (mg/kg)	a rbccancer (mg/kg)	Site ILCR (unitless)	b rbcnoncancer (mg/kg)	Site HQ (unitless)
Benzene	4.00E-01	6.98E-01	5.73E-07	1.11E+02	3.60E-02
Ethylbenzene	2.00E+00	3.68E+00	1.63E-06	4.45E+02	1.35E-02
Site Cumulative ILCR =	2.20E-06	Site Hazard Index =	4.95E-01

a. Cancer rbcs are based on a target Risk of 1E [-06 ]

b. Noncancer rbcs are based on a target Hazard Quotient of 1.0

8. The Cumulative ILCR and HI can now be compared to the target ILCR and target HI to determine whether further action is warranted:

a. Is the Cumulative Site ILCR > the target cancer risk?

Is 2.20E [-06 ]>1E [-06 ]?

Yes

b. Is the HI > the target Site HI?

Is 4.95E [-01 ]>1

No

Because the Cumulative Site ILCR is greater than the target cancer risk for the site, further attention is warranted.

TABLE 1

SUMMARY TABLE

2019 - RESIDENT SOIL RISK-BASED CONCENTRATIONS (RBCS) (MG/KG)

INCIDENTAL INGESTION, DERMAL CONTACT AND INHALATION

Chemical Name	CAS No.	Resident - Soil risk-based concentations (rbcs)
		Cancer Target Risk=1E-6	Noncancer Hazard Quotient=1
		Combined Routes mg/kg	Combined Routes mg/kg
Acetochlor	34256-82-1	NA	1.22E+03
Acetone	67-64-1	NA	4.06E+04
Alachlor	15972-60-8	NA	6.08E+01
Aldrin	309-00-2	2.02E-02	2.10E+00
Aluminum	7429-90-5	NA	7.25E+04
Antimony	7440-36-0	NA	2.60E+01
Arsenic, Inorganic	7440-38-2	2.32E-01	2.10E+01
Barium	7440-39-3	NA	1.12E+04
Benomyl	17804-35-2	1.16E+02	7.90E+02
Benzene	71-43-2	6.98E-01	1.11E+02
Benzo(a)pyrene (a)	50-32-8	7.28E-02	1.72E+01
Beryllium	7440-41-7	5.67E+02	3.45E+01
Bis(2-chloro-1-methyl ethyl)ether	108-60-1	NA	2.80E+03
Boron	7440-42-8	NA	1.47E+04
Bromate	15541-45-4	5.36E-01	2.93E+02
Bromochloromethane	74-97-5	NA	1.93E+02
Bromoxynil	1689-84-5	2.69E+00	9.12E+02
Butylbenzene, n-	104-51-8	NA	3.50E+03
Butylbenzene, sec-	135-98-8	NA	7.01E+03
Butylbenzene, tert-	98-06-6	NA	7.01E+03
Cadmium (food)	7440-43-9	7.56E+02	6.86E+00
Carbaryl	63-25-2	3.17E+02	6.08E+03
Carbon Disulfide	75-15-0	NA	6.08E+02
Carbon tetrachloride	56-23-5	3.72E-01	1.30E+02
Chlorobenzene	108-90-7	NA	4.14E+02
Chromium (III) (insoluble salts)	16065-83-1	NA	4.02E+04
Chromium (VI)	18540-29-9	9.06E-02	1.16E+02
Cobalt	7440-48-4	1.51E+02	2.19E+01
Copper	7440-50-8	NA	1.04E+04
Di (2-ethylhexyl) phthalate	117-81-7	1.98E+01	1.22E+03
Dibromochloropropane	96-12-8	6.00E-03	6.63E+00
Dibromoethane, 1,2-	106-93-4	2.27E-02	1.15E+02
Dichloroethane, 1,1-	75-34-3	2.10E+00	1.40E+04
Dichloroethane, 1,2-	107-06-2	2.85E-01	4.95E+01
Dichloroethylene, cis 1,2-	156-59-2	NA	1.40E+02
Dichloroethylene, trans 1,2-	156-60-5	NA	1.40E+03
Dichloropropane, 1,2-	78-87-5	1.51E+00	2.63E+01
Dioxane, 1,4-	123-91-1	2.78E+00	1.05E+03
Ethylbenzene	100-41-4	3.68E+00	4.45E+02
Fluoranthene	206-44-0	NA	2.30E+03
Fluorene	86-73-7	NA	2.30E+03
Hexachlorobenzene	118-74-1	1.31E-01	5.61E+01
Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX)	121-82-4	4.60E+00	2.90E+02
Iron	7439-89-6	NA	5.13E+04
Isopropylbenzene (cumene)	98-82-8	NA	2.56E+02
Manganese (non-diet)	7439-96-5	NA	1.12E+03
Mercury (elemental)	7439-97-6	NA	3.13E+00
Methyl ethyl ketone	78-93-3	NA	1.70E+04
Methyl tert-butyl ether (MTBE)	1634-04-4	NA	6.49E+02
Molybdenum	7439-98-7	NA	3.66E+02
Naphthalene	91-20-3	2.72E+00	2.24E+02
Nickel	7440-02-0	5.23E+03	9.40E+02
Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX)	2691-41-0	NA	3.70E+03
Pentachlorophenol	87-86-5	4.84E-01	2.37E+02
Pentaerythritol tetranitrate (PETN)	78-11-5	NA	1.22E+02
Perchlorate	14797-73-0	NA	5.13E+01
Perfluoroheptanoic acid (PFHpA) (b)	375-85-9	NA	1.22E+00
Perfluorohexane sulfonic acid (PFHxS) (b)	355-46-4	NA	1.22E+00
Perfluorononanoic acid (PFNA) (b)	375-95-1	NA	1.22E+00
Perfluorooctane sulfonic acid (PFOS) (b)	1763-23-1	NA	1.22E+00
Perfluorooctanoic acid (PFOA) (b)	335-67-1	3.96E+00	1.22E+00
Polychlorinated biphenyls (c)(PCBs)	1336-36-3	1.14E-01	1.13E+00
Propoxur (Baygon)	114-26-1	7.88E+01	2.43E+02
Propyl benzene, n-	103-65-1	NA	2.53E+02
Selenium	7782-49-2	NA	3.66E+02
Silver	7440-22-4	NA	2.37E+02
Tetrachlorodibenzo-p-dioxin, 2,3,7,8- (TCDD)	1746-01-6	2.25E-06	4.91E-05
Tetrachloroethane, 1,1,1,2-	630-20-6	1.32E+00	2.10E+03
Tetrachloroethylene	127-18-4	2.38E+00	1.13E+02
Thallium (soluble Thallium)	7440-28-0 *	NA	7.33E-01
Toluene	108-88-3	NA	7.06E+02
Trichloroethylene (non-moa / mmoa)	79-01-6	6.81E-01	6.21E+00
Trichloropropane, 1,2,3-	96-18-4	3.11E-03	8.67E+00
Trimethylbenzene, 1,2,3- (d)	526-73-8	NA	2.06E+02
Trimethylbenzene, 1,2,4- (d)	95-63-6	NA	1.66E+02
Trimethylbenzene, 1,3,5- (d)	108-67-8	NA	1.44E+02
Trinitrotoluene, 2,4,6- (TNT)	118-96-7	1.15E+01	3.49E+01
Uranium (soluble salts)	NA	NA	4.40E+01
Vanadium	7440-62-2	NA	2.77E+00
Vinyl chloride	75-01-4	9.83E-02	8.51E+01
Xylenes	1330-20-7	NA	2.52E+02
Zinc	7440-66-6	NA	2.20E+04

TABLE 3

SUMMARY TABLE

2019 - RESIDENT AND NONRESIDENTIAL INDOOR AIR risk-based concentrations (rbcs) (5g/m [3) ]

INHALATION

Chemical Name	CAS No.	Indoor Air risk-based concentrations (rbcs)
		Resident - Indoor Air		Nonresidential - Indoor Air
		Cancer Target Risk = 1x10-6	Noncancer Hazard Quotient = 1.0	Cancer Target Risk = 1x10-6	Noncancer Hazard Quotient = 1.0
		Inhalation µg/m3	Inhalation µg/m3	Inhalation µg/m3	Inhalation µg/m3
Benzene	71-43-2	0.13	30.00	1.05	105.12
Carbon tetrachloride	56-23-5	0.17	100.00	1.36	350.40
Chloroethane	75-00-3	--	10000.00	--	35040.00
Chloroform	67-66-3	0.04	97.70	0.36	342.34
Dichloroethane, 1,1-	75-34-3	0.63	--	5.11	--
Dichloroethene, 1,1-	75-35-4	--	200.00	--	700.80
Ethylbenzene	100-41-4	4.00E-01	260.00	3.27E+00	911.04
Mercury (elemental)	7439-97-6	--	0.30	--	0.3 (a)
Methylene chloride	75-09-2	60.34	600.00	817.60	2102.40
Naphthalene	91-20-3	0.03	3.00	0.24	10.51
Tetrachloroethylene	127-18-4	0.63	40.00	5.11	140.16
Trichloroethylene	79-01-6	0.20	0.2 (c)	1.99	0.7 (b)
Trimethylbenzene, 1,2,3-	526-73-8	--	60 (c)	--	210.24 (c)
Trimethylbenzene, 1,2,4-	95-63-6	--	60 (c)	--	210.24 (c)
Trimethylbenzene, 1,3,5-	108-67-8	--	60 (c)	--	210.24 (c)
Vinyl chloride	75-01-4	0.11	100.00	1.86 (d)	350.40

(a) Benzo(a)pyrene cancer-based screening value applicable to benzo(a)pyrene itself and to total benzo(a)pyrene toxic equivalents [B(a)P-TE]. Benzo(a)pyrene noncancer-based value applicable only to benzo(a)pyrene itself.

(b) PFAS - Sum of PFHpA, PFHxS, PFNA, PFOS and PFOA not to exceed 1.22 mg/kg.

(c) Polychlorinated Biphenyls -IRIS high risk and persistence cancer toxicity values employed; noncancer assessment of Total PCBs based on oral reference dose and VF for Aroclor 1254.

* - CAS Number is for Metallic Thallium

Groundwater temperature of 150C used in derivation of volatiziation factors with May 2018 Regional Screening Level Calculator.

Csat substitution used if soil inhalation screening value greater than Csat. Csats derived using May 2018 Regional Screening Level Calculator.

All cancer-based soil inhalation screening values were less than respective Csat thus no substitutions.

Noncancer-based soil inhalation screening value above respective Csat thus Csat substitiouion employed for the following:

Acetone, Carbon Disulfide, Ethylbenzene, Isopropylbenzene (cumene), Mercury (elemental), Methyl ethyl ketone, Methyl tert-butyl ether, n-Propyl benzene, Tetrachloroethylene, Toluene, Trimethyl benzenes, Xylenes.

(d) Trimethyl benzenes -Sum of the three isomers not to exceed 1.44E+02 mg/kg, based on the most conservative value derived for an individual isomer.

TABLE 2

SUMMARY TABLE

2019 - COMMERCIAL WORKER SOIL risk-based concentrations (rbcs) (mg/kg)

INCIDENTAL INGESTION, DERMAL CONTACT AND INHALATION

Chemical Name	CAS No.	Commerical Worker - Soil risk-based concentations (rbcs)
		Cancer Target Risk=1E-6	Noncancer Hazard Quotient=1
		Combined Routes mg/kg	Combined Routes mg/kg
Acetochlor	34256-82-1	-	1.44E+04
Acetone	67-64-1	-	1.00E+05
Alachlor	15972-60-8	-	7.18E+02
Aldrin	309-00-2	9.76E-02	2.15E+01
Aluminum	7429-90-5	-	9.42E+05
Antimony	7440-36-0	-	3.19E+02
Arsenic, Inorganic	7440-38-2	1.41E+00	2.71E+02
Barium	7440-39-3	-	1.27E+05
Benomyl	17804-35-2	7.01E+02	9.34E+03
Benzene	71-43-2	4.19E+00	4.18E+02
Benzo(a)pyrene (a)	50-32-8	1.54E+00	1.94E+02
Beryllium	7440-41-7	4.63E+03	2.89E+02
Bis(2-chloro-1-methyl ethyl)ether	108-60-1	-	3.63E+04
Boron	7440-42-8	-	1.96E+05
Bromate	15541-45-4	3.27E+00	3.92E+03
Bromochloromethane	74-97-5	-	5.97E+02
Bromoxynil	1689-84-5	1.63E+01	1.08E+04
Butylbenzene, n-	104-51-8	-	5.11E+04
Butylbenzene, sec-	135-98-8	-	1.02E+05
Butylbenzene, tert-	98-06-6	-	1.02E+05
Cadmium (food)	7440-43-9	6.18E+03	8.72E+01
Carbaryl	63-25-2	1.91E+03	7.18E+04
Carbon Disulfide	75-15-0	-	6.62E+02
Carbon tetrachloride	56-23-5	2.23E+00	3.59E+02
Chlorobenzene	108-90-7	-	7.26E+02
Chromium (III) (insoluble salts)	16065-83-1	-	3.60E+05
Chromium (VI)	18540-29-9	1.75E+00	1.14E+03
Cobalt	7440-48-4	1.24E+03	2.91E+02
Copper	7440-50-8	-	1.39E+05
Di (2-ethylhexyl) phthalate	117-81-7	1.20E+02	1.44E+04
Dibromochloropropane	96-12-8	6.15E-02	2.75E+01
Dibromoethane, 1,2-	106-93-4	1.39E-01	3.49E+02
Dichloroethane, 1,1-	75-34-3	1.26E+01	2.04E+05
Dichloroethane, 1,2-	107-06-2	1.71E+00	1.40E+02
Dichloroethylene, cis 1,2-	156-59-2	-	1.81E+03
Dichloroethylene, trans 1,2-	156-60-5	-	1.81E+04
Dichloropropane, 1,2-	78-87-5	9.06E+00	6.81E+01
Dioxane, 1,4-	123-91-1	1.69E+01	4.49E+03
Ethylbenzene	100-41-4	2.21E+01	4.73E+02
Fluoranthene	206-44-0	-	2.64E+04
Fluorene	86-73-7	-	2.64E+04
Hexachlorobenzene	118-74-1	6.86E-01	5.74E+02
Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX)	121-82-4	2.80E+01	3.84E+03
Iron	7439-89-6	-	6.86E+05
Isopropylbenzene (cumene)	98-82-8	-	2.64E+02
Manganese (non-diet)	7439-96-5	-	1.14E+04
Mercury (elemental)	7439-97-6	-	3.13E+00
Methyl ethyl ketone	78-93-3	-	2.70E+04
Methyl tert-butyl ether (MTBE)	1634-04-4	-	4.46E+03
Molybdenum	7439-98-7	-	4.90E+03
Naphthalene	91-20-3	1.64E+01	6.78E+02
Nickel	7440-02-0	4.28E+04	9.71E+03
Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX)	2691-41-0	-	4.98E+04
Pentachlorophenol	87-86-5	2.90E+00	2.48E+03
Pentaerythritol tetranitrate (PETN)	78-11-5	-	1.44E+03
Perchlorate	14797-73-0	-	6.86E+02
Perfluoroheptanoic acid (PFHpA) (b)	375-85-9	-	remove
Perfluorohexane sulfonic acid (PFHxS) (b)	355-46-4	-	1.44E+01
Perfluorononanoic acid (PFNA) (b)	375-95-1	-	1.44E+01
Perfluorooctane sulfonic acid (PFOS) (b)	1763-23-1	-	1.44E+01
Perfluorooctanoic acid (PFOA) (b)	335-67-1	2.39E+01	1.44E+01
Polychlorinated biphenyls (PCBs) (c)	1336-36-3	6.83E-01	1.28E+01
Propoxur (Baygon)	114-26-1	4.76E+02	2.87E+03
Propyl benzene, n-	103-65-1	-	2.61E+02
Selenium	7782-49-2	-	4.90E+03
Silver	7440-22-4	-	2.48E+03
Tetrachlorodibenzo-p-dioxin, 2,3,7,8- (TCDD)	1746-01-6	1.37E-05	6.35E-04
Tetrachloroethane, 1,1,1,2-	630-20-6	8.00E+00	3.07E+04
Tetrachloroethylene	127-18-4	1.43E+01	1.51E+02
Thallium (soluble Thallium)	7440-28-0 *	-	1.96E+05
Toluene	108-88-3	-	7.98E+02
Trichloroethylene (non-moa)	79-01-6	6.47E+00	1.86E+01
Trichloropropane, 1,2,3-	96-18-4	7.05E-02	2.29E+01
Trimethylbenzene, 1,2,3- (d)	526-73-8	-	2.82E+02
Trimethylbenzene, 1,2,4- (d)	95-63-6	-	2.12E+02
Trimethylbenzene, 1,3,5- (d)	108-67-8	-	1.77E+02
Trinitrotoluene, 2,4,6- (TNT)	118-96-7	7.00E+01	4.50E+02
Uranium (soluble salts)	Uranium	-	5.88E+02
Vanadium	7440-62-2	-	2.72E+01
Vinyl chloride	75-01-4	5.93E-01	3.24E+02
Xylenes	1330-20-7	-	2.57E+02
Zinc	7440-66-6	-	2.94E+05

(a) Benzo(a)pyrene cancer-based screening value applicable to benzo(a)pyrene itself and to total benzo(a)pyrene toxic equivalents [B(a)P-TE]. Benzo(a)pyrene noncancer-based value applicable only to benzo(a)pyrene itself.

(b) PFAS - Sum of PFHpA, PFHxS, PFNA, PFOS and PFOA not to exceed 14.4 mg/kg.

(c) Polychlorinated Biphenyls -IRIS high risk and persistence cancer toxicity values employed; noncancer assessment of Total PCBs based on oral reference dose and VF for Aroclor 1254.

* - CAS Number is for Metallic Thallium

Groundwater temperature of 150C used in derivation of volatiziation factors with May 2018 Regional Screening Level Calculator.

Csat substitution used if soil inhalation screening value greater than Csat. Csats derived using May 2018 Regional Screening Level Calculator.

(d) Trimethyl benzenes -Sum of the three isomers not to exceed 1.77+02 mg/kg, based on the most conservative value derived for an individual isomer.

(a) Mercury (elemental) - Due to the developmental toxicity associated with mercury exposure, the inhalation Reference Concentratio is used as the nonresidential air value without adjusting for exposure period.

(b) Trichloroethylene - Due to the nature and severity of a particular non-cancer endpoint (fetal cardiac malformations) that may be associated with a brief window of susceptibility, there is significant uncertainty regarding the exposure period of concern. Thus, a target hazard quotient of 0.1 was used in the calculatin of noncancer values.

(c) Trimethyl benzenes - The sum of the 3 isomers should not exceed 60 5g/m [3 ] for Resident - Indoor Air and not exceed 210.24 5g/m [3 ] for Nonresidential - Indoor Air

(d) Vinyl chloride - Inhalation Unit Risk of 4.4E-06 (5g/m [3) -1 ] based on continuous lifetime exposure during adulthood using to develop cancer based value for Nonresidential - Indoor Air

Section E1 INSTRUCTIONS FOR CALCULATING CUMULATIVE CANCER RISK AND HAZARD INDEX HYPOTHETICAL HUMAN RECEPTOR: SOIL AND/OR INDOOR AIR

Nota bene: risk-based concentration (rbc) means the calculated concentration of a chemical (or group of chemicals) in an environmental medium estimated to correspond to a fixed level of risk e.g., a target Hazard Quotient (THQ) of 1.0 for noncarcinogenic (systemic, threshold) effects or target incremental lifetime cancer risk (ILCR) of one-in-one-million (1x10 [-6) ], for a predefined hypothetical human exposure scenario. Examples of rbcs for different environmental media based on different hypothetical exposure scenarios are included in this appendix as Tables 1-3.

I. SAMPLE-WISE APPROACH

For each Hypothetical Human Receptor Scenario and exposure medium (i.e., Soil, Indoor Air):

1. In accordance with the IRULE, for each sample, identify chemicals that are present above detection and retained for further consideration.

2. For each chemical, identify and record its receptor and medium-specific cancer and noncancer risk-based concentration (rbc) if both are available. Segregate cancer (c) from noncancer (nc) rbcs.

3. For each carcinogen in a sample, calculate the associated Incremental Lifetime Cancer Risk (ILCR):

a. Calculate the ILCR associated with each individual chemical that has a cancer rbc:

For a given chemical i in sample j:

Click here to view image

b. Calculate the cumulative ILCR across all chemicals in a sample that have a cancer rbc:

For a given number of chemicals (n) in sample j, where i is the first chemical:

Click here to view image

4. For each noncarcinogen in a sample, calculate the associated Hazard Quotient (HQ):

a. Calculate the HQ associated with each individual chemical that has a noncancer rbc:

For given a chemical i in sample j:

Click here to view image

b. Calculate the Hazard Index (sum of HQs) across all chemicals in a sample that have a noncancer rbc. Do not segregate chemicals by critical effect.

For a given number of chemicals (n) in sample j, where i is the first chemical:

Click here to view image

Example Sample-wise Calculation for Direct Contact to Soil: Residential Scenario

1. Benzene and ethylbenzene are detected in Soil Sample S01 at the following concentrations

Analyte	Soil Sample S01 (mg/kg)
Benzene	4.00E-01
Ethylbenzene	6.00E+00

2. Use Table 1 to find Residential Soil cancer and noncancer rbcs for benzene and ethylbenzene:

Analyte	Sample Concentration Soil Sample S01 (mg/kg)	Resident - Soil rbcs from Table 1
		rbccancer * (mg/kg)	rbcnoncancer * (mg/kg)
Benzene	4.00E-01	6.98E-01	1.11E+02
Ethylbenzene	6.00E+00	3.68E+00	4.45E+02

[*] Cancer rbcs are based on target ILCR=1E [-06; ] noncancer rbcs are based on target HQ=1.0

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7. It may be helpful to consolidate all this information into a table such as the following:

Resident - Soil
CANCER		NONCANCER
Analyte	Site Concentration Sample S01 (mg/kg)	a rbccancer (mg/kg)	Sample S01 ILCR (unitless)	b rbcnoncancer (mg/kg)	Sample S01 HQ (unitless)
Benzene	4.00E-01	6.98E-01	5.73E-07	1.11E+02	3.60E-02
Ethylbenzene	2.00E+00	3.68E+00	1.63E-06	4.45E+02	1.35E-02
Sample S01 Cumulative ILCR =	2.20E-06	Sample S01 Hazard Index =	4.95E-01

a. Cancer rbcs are based on a target Risk of 1E [-06 ]

b. Noncancer rbcs are based on a target Hazard Quotient of 1.0

8. The Cumulative ILCR and HI can now be compared to the target ILCR and target HI to determine whether further action is warranted:

a. Is the cumulative ILCR > the target cancer risk?

Is 2.20E [-06 ]>1E [-06 ]?

Yes

b. Is the HI > the target HI?

Is 4.59E [-01 ]>1

No

c. Because the Cumulative ILCR is greater than the target ILCR for the site, further attention is warranted.

II. SITE-WIDE/EXPOSURE UNIT APPROACH: Summary Statistic used as Exposure Point Concentration

For each Hypothetical Human Receptor Scenario and exposure medium (i.e., Soil, Indoor Air):

1. In accordance with the IRULE, for each site, or each exposure unit if appropriate, identify chemicals that are present above detection and retained for further consideration

2. Use appropriate Summary Statistic to develop chemical-specific Exposure Point Concentrations (EPCs).

3. For each chemical, identify and record its receptor and medium-specific cancer and noncancer risk-based concentration (rbc), if both are available. Segregate cancer (c) from noncancer (nc) rbcs.

4. For each carcinogen, calculate the associated Site Incremental Lifetime Cancer Risk (ILCR):

a. Calculate the ILCR associated with each individual chemical that has a cancer rbc:

For given chemical i:

Click here to view image

b. Calculate the cumulative Site ILCR across all the chemicals that have a cancer rbc:

For a given number of chemicals ( n), where i is the first chemical:

Click here to view image

5. For each noncarcinogen, calculate the associated Site Hazard Quotient (HQ):

a. Calculate the HQ associated with each individual chemical that has a noncancer rbc:

For given chemical i:

Click here to view image

b. Calculate the Hazard Index (sum of HQs) across all chemicals that have a noncancer rbc. Do not segregate chemicals by critical effect.:

For a given number of chemicals ( n), where i is the first chemical:

Click here to view image

Example Site-wide Calculation for Direct Contact to Soil: Residential Scenario

1. Benzene and ethylbenzene are detected in soil. The following Site-wide Exposure Point Concentrations (EPCs) are determined:

Analyte	Soil Exposure Point Concentration (mg/kg)
Benzene	4.00E-01
Ethylbenzene	6.00E+00

2. Use Table 1 to find Residential Soil cancer and noncancer rbcs for Benzene and Ethylbenzene:

Resident - Soil rbcs from Table 1
Analyte	Soil Concentration (mg/kg)	rbccancer* (mg/kg)	rbcnoncancer* (mg/kg)
Benzene	4.00E-01	6.98E-01	1.11E+02
Ethylbenzene	6.00E+00	3.68E+00	4.45E+02

[* ] Cancer rbcs are based on a target ICLR=1E [-06; ] noncancer rbcs are based on target HQ=1.0

Click here to view image

Click here to view image

7. It may be helpful to consolidate all this information into a table such as the following:

Resident - Soil
CANCER		NONCANCER
Analyte	Site Exposure Point Concentration (mg/kg)	a rbccancer (mg/kg)	Site ILCR (unitless)	b rbcnoncancer (mg/kg)	Site HQ (unitless)
Benzene	4.00E-01	6.98E-01	5.73E-07	1.11E+02	3.60E-02
Ethylbenzene	2.00E+00	3.68E+00	1.63E-06	4.45E+02	1.35E-02
Site Cumulative ILCR =	2.20E-06	Site Hazard Index =	4.95E-01

a. Cancer rbcs are based on a target Risk of 1E [-06 ]

b. Noncancer rbcs are based on a target Hazard Quotient of 1.0

8. The Cumulative ILCR and HI can now be compared to the target ILCR and target HI to determine whether further action is warranted:

a. Is the Cumulative Site ILCR > the target cancer risk?

Is 2.20E [-06 ]>1E [-06 ]?

Yes

b. Is the HI > the target Site HI?

Is 4.95E [-01 ]>1

No

Because the Cumulative Site ILCR is greater than the target cancer risk for the site, further attention is warranted.

TABLE 1

SUMMARY TABLE

2019 - RESIDENT SOIL RISK-BASED CONCENTRATIONS (RBCS) (MG/KG)

INCIDENTAL INGESTION, DERMAL CONTACT AND INHALATION

Chemical Name	CAS No.	Resident - Soil risk-based concentations (rbcs)
		Cancer Target Risk=1E-6	Noncancer Hazard Quotient=1
		Combined Routes mg/kg	Combined Routes mg/kg
Acetochlor	34256-82-1	NA	1.22E+03
Acetone	67-64-1	NA	4.06E+04
Alachlor	15972-60-8	NA	6.08E+01
Aldrin	309-00-2	2.02E-02	2.10E+00
Aluminum	7429-90-5	NA	7.25E+04
Antimony	7440-36-0	NA	2.60E+01
Arsenic, Inorganic	7440-38-2	2.32E-01	2.10E+01
Barium	7440-39-3	NA	1.12E+04
Benomyl	17804-35-2	1.16E+02	7.90E+02
Benzene	71-43-2	6.98E-01	1.11E+02
Benzo(a)pyrene (a)	50-32-8	7.28E-02	1.72E+01
Beryllium	7440-41-7	5.67E+02	3.45E+01
Bis(2-chloro-1-methyl ethyl)ether	108-60-1	NA	2.80E+03
Boron	7440-42-8	NA	1.47E+04
Bromate	15541-45-4	5.36E-01	2.93E+02
Bromochloromethane	74-97-5	NA	1.93E+02
Bromoxynil	1689-84-5	2.69E+00	9.12E+02
Butylbenzene, n-	104-51-8	NA	3.50E+03
Butylbenzene, sec-	135-98-8	NA	7.01E+03
Butylbenzene, tert-	98-06-6	NA	7.01E+03
Cadmium (food)	7440-43-9	7.56E+02	6.86E+00
Carbaryl	63-25-2	3.17E+02	6.08E+03
Carbon Disulfide	75-15-0	NA	6.08E+02
Carbon tetrachloride	56-23-5	3.72E-01	1.30E+02
Chlorobenzene	108-90-7	NA	4.14E+02
Chromium (III) (insoluble salts)	16065-83-1	NA	4.02E+04
Chromium (VI)	18540-29-9	9.06E-02	1.16E+02
Cobalt	7440-48-4	1.51E+02	2.19E+01
Copper	7440-50-8	NA	1.04E+04
Di (2-ethylhexyl) phthalate	117-81-7	1.98E+01	1.22E+03
Dibromochloropropane	96-12-8	6.00E-03	6.63E+00
Dibromoethane, 1,2-	106-93-4	2.27E-02	1.15E+02
Dichloroethane, 1,1-	75-34-3	2.10E+00	1.40E+04
Dichloroethane, 1,2-	107-06-2	2.85E-01	4.95E+01
Dichloroethylene, cis 1,2-	156-59-2	NA	1.40E+02
Dichloroethylene, trans 1,2-	156-60-5	NA	1.40E+03
Dichloropropane, 1,2-	78-87-5	1.51E+00	2.63E+01
Dioxane, 1,4-	123-91-1	2.78E+00	1.05E+03
Ethylbenzene	100-41-4	3.68E+00	4.45E+02
Fluoranthene	206-44-0	NA	2.30E+03
Fluorene	86-73-7	NA	2.30E+03
Hexachlorobenzene	118-74-1	1.31E-01	5.61E+01
Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX)	121-82-4	4.60E+00	2.90E+02
Iron	7439-89-6	NA	5.13E+04
Isopropylbenzene (cumene)	98-82-8	NA	2.56E+02
Manganese (non-diet)	7439-96-5	NA	1.12E+03
Mercury (elemental)	7439-97-6	NA	3.13E+00
Methyl ethyl ketone	78-93-3	NA	1.70E+04
Methyl tert-butyl ether (MTBE)	1634-04-4	NA	6.49E+02
Molybdenum	7439-98-7	NA	3.66E+02
Naphthalene	91-20-3	2.72E+00	2.24E+02
Nickel	7440-02-0	5.23E+03	9.40E+02
Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX)	2691-41-0	NA	3.70E+03
Pentachlorophenol	87-86-5	4.84E-01	2.37E+02
Pentaerythritol tetranitrate (PETN)	78-11-5	NA	1.22E+02
Perchlorate	14797-73-0	NA	5.13E+01
Perfluoroheptanoic acid (PFHpA) (b)	375-85-9	NA	1.22E+00
Perfluorohexane sulfonic acid (PFHxS) (b)	355-46-4	NA	1.22E+00
Perfluorononanoic acid (PFNA) (b)	375-95-1	NA	1.22E+00
Perfluorooctane sulfonic acid (PFOS) (b)	1763-23-1	NA	1.22E+00
Perfluorooctanoic acid (PFOA) (b)	335-67-1	3.96E+00	1.22E+00
Polychlorinated biphenyls (c)(PCBs)	1336-36-3	1.14E-01	1.13E+00
Propoxur (Baygon)	114-26-1	7.88E+01	2.43E+02
Propyl benzene, n-	103-65-1	NA	2.53E+02
Selenium	7782-49-2	NA	3.66E+02
Silver	7440-22-4	NA	2.37E+02
Tetrachlorodibenzo-p-dioxin, 2,3,7,8- (TCDD)	1746-01-6	2.25E-06	4.91E-05
Tetrachloroethane, 1,1,1,2-	630-20-6	1.32E+00	2.10E+03
Tetrachloroethylene	127-18-4	2.38E+00	1.13E+02
Thallium (soluble Thallium)	7440-28-0 *	NA	7.33E-01
Toluene	108-88-3	NA	7.06E+02
Trichloroethylene (non-moa / mmoa)	79-01-6	6.81E-01	6.21E+00
Trichloropropane, 1,2,3-	96-18-4	3.11E-03	8.67E+00
Trimethylbenzene, 1,2,3- (d)	526-73-8	NA	2.06E+02
Trimethylbenzene, 1,2,4- (d)	95-63-6	NA	1.66E+02
Trimethylbenzene, 1,3,5- (d)	108-67-8	NA	1.44E+02
Trinitrotoluene, 2,4,6- (TNT)	118-96-7	1.15E+01	3.49E+01
Uranium (soluble salts)	NA	NA	4.40E+01
Vanadium	7440-62-2	NA	2.77E+00
Vinyl chloride	75-01-4	9.83E-02	8.51E+01
Xylenes	1330-20-7	NA	2.52E+02
Zinc	7440-66-6	NA	2.20E+04

TABLE 2

SUMMARY TABLE

2019 - COMMERCIAL WORKER SOIL risk-based concentrations (rbcs) (mg/kg)

INCIDENTAL INGESTION, DERMAL CONTACT AND INHALATION

Chemical Name	CAS No.	Commerical Worker - Soil risk-based concentations (rbcs)
		Cancer Target Risk=1E-6	Noncancer Hazard Quotient=1
		Combined Routes mg/kg	Combined Routes mg/kg
Acetochlor	34256-82-1	-	1.44E+04
Acetone	67-64-1	-	1.00E+05
Alachlor	15972-60-8	-	7.18E+02
Aldrin	309-00-2	9.76E-02	2.15E+01
Aluminum	7429-90-5	-	9.42E+05
Antimony	7440-36-0	-	3.19E+02
Arsenic, Inorganic	7440-38-2	1.41E+00	2.71E+02
Barium	7440-39-3	-	1.27E+05
Benomyl	17804-35-2	7.01E+02	9.34E+03
Benzene	71-43-2	4.19E+00	4.18E+02
Benzo(a)pyrene (a)	50-32-8	1.54E+00	1.94E+02
Beryllium	7440-41-7	4.63E+03	2.89E+02
Bis(2-chloro-1-methyl ethyl)ether	108-60-1	-	3.63E+04
Boron	7440-42-8	-	1.96E+05
Bromate	15541-45-4	3.27E+00	3.92E+03
Bromochloromethane	74-97-5	-	5.97E+02
Bromoxynil	1689-84-5	1.63E+01	1.08E+04
Butylbenzene, n-	104-51-8	-	5.11E+04
Butylbenzene, sec-	135-98-8	-	1.02E+05
Butylbenzene, tert-	98-06-6	-	1.02E+05
Cadmium (food)	7440-43-9	6.18E+03	8.72E+01
Carbaryl	63-25-2	1.91E+03	7.18E+04
Carbon Disulfide	75-15-0	-	6.62E+02
Carbon tetrachloride	56-23-5	2.23E+00	3.59E+02
Chlorobenzene	108-90-7	-	7.26E+02
Chromium (III) (insoluble salts)	16065-83-1	-	3.60E+05
Chromium (VI)	18540-29-9	1.75E+00	1.14E+03
Cobalt	7440-48-4	1.24E+03	2.91E+02
Copper	7440-50-8	-	1.39E+05
Di (2-ethylhexyl) phthalate	117-81-7	1.20E+02	1.44E+04
Dibromochloropropane	96-12-8	6.15E-02	2.75E+01
Dibromoethane, 1,2-	106-93-4	1.39E-01	3.49E+02
Dichloroethane, 1,1-	75-34-3	1.26E+01	2.04E+05
Dichloroethane, 1,2-	107-06-2	1.71E+00	1.40E+02
Dichloroethylene, cis 1,2-	156-59-2	-	1.81E+03
Dichloroethylene, trans 1,2-	156-60-5	-	1.81E+04
Dichloropropane, 1,2-	78-87-5	9.06E+00	6.81E+01
Dioxane, 1,4-	123-91-1	1.69E+01	4.49E+03
Ethylbenzene	100-41-4	2.21E+01	4.73E+02
Fluoranthene	206-44-0	-	2.64E+04
Fluorene	86-73-7	-	2.64E+04
Hexachlorobenzene	118-74-1	6.86E-01	5.74E+02
Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX)	121-82-4	2.80E+01	3.84E+03
Iron	7439-89-6	-	6.86E+05
Isopropylbenzene (cumene)	98-82-8	-	2.64E+02
Manganese (non-diet)	7439-96-5	-	1.14E+04
Mercury (elemental)	7439-97-6	-	3.13E+00
Methyl ethyl ketone	78-93-3	-	2.70E+04
Methyl tert-butyl ether (MTBE)	1634-04-4	-	4.46E+03
Molybdenum	7439-98-7	-	4.90E+03
Naphthalene	91-20-3	1.64E+01	6.78E+02
Nickel	7440-02-0	4.28E+04	9.71E+03
Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX)	2691-41-0	-	4.98E+04
Pentachlorophenol	87-86-5	2.90E+00	2.48E+03
Pentaerythritol tetranitrate (PETN)	78-11-5	-	1.44E+03
Perchlorate	14797-73-0	-	6.86E+02
Perfluoroheptanoic acid (PFHpA) (b)	375-85-9	-	remove
Perfluorohexane sulfonic acid (PFHxS) (b)	355-46-4	-	1.44E+01
Perfluorononanoic acid (PFNA) (b)	375-95-1	-	1.44E+01
Perfluorooctane sulfonic acid (PFOS) (b)	1763-23-1	-	1.44E+01
Perfluorooctanoic acid (PFOA) (b)	335-67-1	2.39E+01	1.44E+01
Polychlorinated biphenyls (PCBs) (c)	1336-36-3	6.83E-01	1.28E+01
Propoxur (Baygon)	114-26-1	4.76E+02	2.87E+03
Propyl benzene, n-	103-65-1	-	2.61E+02
Selenium	7782-49-2	-	4.90E+03
Silver	7440-22-4	-	2.48E+03
Tetrachlorodibenzo-p-dioxin, 2,3,7,8- (TCDD)	1746-01-6	1.37E-05	6.35E-04
Tetrachloroethane, 1,1,1,2-	630-20-6	8.00E+00	3.07E+04
Tetrachloroethylene	127-18-4	1.43E+01	1.51E+02
Thallium (soluble Thallium)	7440-28-0 *	-	1.96E+05
Toluene	108-88-3	-	7.98E+02
Trichloroethylene (non-moa)	79-01-6	6.47E+00	1.86E+01
Trichloropropane, 1,2,3-	96-18-4	7.05E-02	2.29E+01
Trimethylbenzene, 1,2,3- (d)	526-73-8	-	2.82E+02
Trimethylbenzene, 1,2,4- (d)	95-63-6	-	2.12E+02
Trimethylbenzene, 1,3,5- (d)	108-67-8	-	1.77E+02
Trinitrotoluene, 2,4,6- (TNT)	118-96-7	7.00E+01	4.50E+02
Uranium (soluble salts)	Uranium	-	5.88E+02
Vanadium	7440-62-2	-	2.72E+01
Vinyl chloride	75-01-4	5.93E-01	3.24E+02
Xylenes	1330-20-7	-	2.57E+02
Zinc	7440-66-6	-	2.94E+05

TABLE 3

SUMMARY TABLE

2019 - RESIDENT AND NONRESIDENTIAL INDOOR AIR risk-based concentrations (rbcs) (5g/m [3) ]

INHALATION

Chemical Name	CAS No.	Indoor Air risk-based concentrations (rbcs)
		Resident - Indoor Air		Nonresidential - Indoor Air
		Cancer Target Risk = 1x10-6	Noncancer Hazard Quotient = 1.0	Cancer Target Risk = 1x10-6	Noncancer Hazard Quotient = 1.0
		Inhalation µg/m3	Inhalation µg/m3	Inhalation µg/m3	Inhalation µg/m3
Benzene	71-43-2	0.13	30.00	1.05	105.12
Carbon tetrachloride	56-23-5	0.17	100.00	1.36	350.40
Chloroethane	75-00-3	--	10000.00	--	35040.00
Chloroform	67-66-3	0.04	97.70	0.36	342.34
Dichloroethane, 1,1-	75-34-3	0.63	--	5.11	--
Dichloroethene, 1,1-	75-35-4	--	200.00	--	700.80
Ethylbenzene	100-41-4	4.00E-01	260.00	3.27E+00	911.04
Mercury (elemental)	7439-97-6	--	0.30	--	0.3 (a)
Methylene chloride	75-09-2	60.34	600.00	817.60	2102.40
Naphthalene	91-20-3	0.03	3.00	0.24	10.51
Tetrachloroethylene	127-18-4	0.63	40.00	5.11	140.16
Trichloroethylene	79-01-6	0.20	0.2 (c)	1.99	0.7 (b)
Trimethylbenzene, 1,2,3-	526-73-8	--	60 (c)	--	210.24 (c)
Trimethylbenzene, 1,2,4-	95-63-6	--	60 (c)	--	210.24 (c)
Trimethylbenzene, 1,3,5-	108-67-8	--	60 (c)	--	210.24 (c)
Vinyl chloride	75-01-4	0.11	100.00	1.86 (d)	350.40

(a) Benzo(a)pyrene cancer-based screening value applicable to benzo(a)pyrene itself and to total benzo(a)pyrene toxic equivalents [B(a)P-TE]. Benzo(a)pyrene noncancer-based value applicable only to benzo(a)pyrene itself.

(b) PFAS - Sum of PFHpA, PFHxS, PFNA, PFOS and PFOA not to exceed 1.22 mg/kg.

(c) Polychlorinated Biphenyls -IRIS high risk and persistence cancer toxicity values employed; noncancer assessment of Total PCBs based on oral reference dose and VF for Aroclor 1254.

* - CAS Number is for Metallic Thallium

Groundwater temperature of 150C used in derivation of volatiziation factors with May 2018 Regional Screening Level Calculator.

Csat substitution used if soil inhalation screening value greater than Csat. Csats derived using May 2018 Regional Screening Level Calculator.

All cancer-based soil inhalation screening values were less than respective Csat thus no substitutions.

Noncancer-based soil inhalation screening value above respective Csat thus Csat substitiouion employed for the following:

Acetone, Carbon Disulfide, Ethylbenzene, Isopropylbenzene (cumene), Mercury (elemental), Methyl ethyl ketone, Methyl tert-butyl ether, n-Propyl benzene, Tetrachloroethylene, Toluene, Trimethyl benzenes, Xylenes.

(d) Trimethyl benzenes -Sum of the three isomers not to exceed 1.44E+02 mg/kg, based on the most conservative value derived for an individual isomer.

(a) Benzo(a)pyrene cancer-based screening value applicable to benzo(a)pyrene itself and to total benzo(a)pyrene toxic equivalents [B(a)P-TE]. Benzo(a)pyrene noncancer-based value applicable only to benzo(a)pyrene itself.

(b) PFAS - Sum of PFHpA, PFHxS, PFNA, PFOS and PFOA not to exceed 14.4 mg/kg.

(c) Polychlorinated Biphenyls -IRIS high risk and persistence cancer toxicity values employed; noncancer assessment of Total PCBs based on oral reference dose and VF for Aroclor 1254.

* - CAS Number is for Metallic Thallium

Groundwater temperature of 150C used in derivation of volatiziation factors with May 2018 Regional Screening Level Calculator.

Csat substitution used if soil inhalation screening value greater than Csat. Csats derived using May 2018 Regional Screening Level Calculator.

(d) Trimethyl benzenes -Sum of the three isomers not to exceed 1.77+02 mg/kg, based on the most conservative value derived for an individual isomer.

(a) Mercury (elemental) - Due to the developmental toxicity associated with mercury exposure, the inhalation Reference Concentratio is used as the nonresidential air value without adjusting for exposure period.

(b) Trichloroethylene - Due to the nature and severity of a particular non-cancer endpoint (fetal cardiac malformations) that may be associated with a brief window of susceptibility, there is significant uncertainty regarding the exposure period of concern. Thus, a target hazard quotient of 0.1 was used in the calculatin of noncancer values.

(c) Trimethyl benzenes - The sum of the 3 isomers should not exceed 60 5g/m [3 ] for Resident - Indoor Air and not exceed 210.24 5g/m [3 ] for Nonresidential - Indoor Air

(d) Vinyl chloride - Inhalation Unit Risk of 4.4E-06 (5g/m [3) -1 ] based on continuous lifetime exposure during adulthood using to develop cancer based value for Nonresidential - Indoor Air

Appendix F Toxicity Equivalence Factors

Some chemicals are members of the same family or group and have been shown to exhibit similar toxicological properties; however, each chemical may differ in the degree of toxicity (EPA, 2019). In some such instances, a toxicity (sometimes referred to as toxic) equivalency factor (TEF) or relative potency factor (RPF) must be applied to convert the reported concentration of each member of the group to a toxicity (sometimes referred to as toxic) equivalent concentration (TEQ) or to toxic equivalents (TE) relative to the toxicity of the index chemical for the group. The index chemical is assigned a TEF or RPF of 1. Total TEQ or TE can be compared to risk-based values derived for the index chemical or assessed using as any other single chemical in a quantitative risk assessment.

Dioxins, Furans and dioxin-like Polychlorinated Biphenyls (PCBs)

The index chemical for this group is 2,3,7,8-Tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD). As of this writing, Health recommends that the 2005 World Health Organization Toxic Equivalency Factors (Van den Berg et al., 2006) be employed in the evaluation of dioxins, furans and dioxin-like PCBs. These values are also presented in the May 2013 U.S. EPA fact sheet, "Use of Dioxin TEFs in Calculating Dioxin TEQs at CERCLA and RCRA Sites" which references the 2010 U.S. EPA report, "Recommended Toxicity Equivalency Factors (TEFs) for Human Health Risk Assessments of 2,3,7,8-Tetrachlorodibenzo-p-dioxin and Dioxin-Like Compounds" (EPA, 2019). TEFs for Di-ortho PCBs may be obtained from Ahlborg, U.G. et al., 1994 (EPA, 2019). TEFs may be applied to the ingestion, dermal (see EPA, 2004) or inhalation routes of exposure and adjusted values may be used in the assessment of both cancer and noncarcinogenic effects (EPA, 2013). The sum of adjusted concentrations is often referred to as 2,3,7,8-TCDD TEQ.

Dioxin Toxicity Equivalence Factors (EPA, 2019)

CAS Registry Number	Compound	2,3,7,8-TCDD Toxicity Equivalence Factor
Chlorinated dibenzo-p-dioxins
1746-01-6	2,3,7,8-TCDD	1
40321-76-4	1,2,3,7,8-PeCDD	1
39227-28-6	1,2,3,4,7,8-HxCDD	0.1
72918-21-9	1,2,3,6,7,8-HxCDD	0.1
57653-85-7	1,2,3,7,8,9-HxCDD	0.1
35822-46-9	1,2,3,4,6,7,8-HpCDD	0.01
3268-87-9	OCDD	0.0003
Chlorinated dibenzofurans
51207-31-9	2,3,7,8-TCDF	0.1
57117-41-6	1,2,3,7,8-PeCDF	0.03
57117-31-4	2,3,4,7,8-PeCDF	0.3
70648-26-9	1,2,3,4,7,8-HxCDF	0.1
57117-44-9	1,2,3,6,7,8-HxCDF	0.1
72918-21-9	1,2,3,7,8,9-HxCDF	0.1
60851-34-5	2,3,4,6,7,8-HxCDF	0.1
35822-46-9	1,2,3,4,6,7,8-HpCDF	0.01
55673-89-7	1,2,3,4,7,8,9-HpCDF	0.01
39001-02-0	OCDF	0.0003

PCBs
IUPAC No.	Structure
Non- ortho
32598-13-3	77	3,3',4,4'-TetraCB	0.0001
70362-50-4	81	3,4,4',5-TetraCB	0.0003
57465-28-8	126	3,3',4,4',5-PeCB	0.1
32774-16-6	169	3,3',4,4',5,5'-HxCB	0.03
Mono- ortho
32598-14-4	105	2,3,3',4,4'-PeCB	0.00003
74472-37-0	114	2,3,4,4',5-PeCB	0.00003
31508-00-6	118	2,3',4,4',5-PeCB	0.00003
65510-44-3	123	2',3,4,4',5-PeCB	0.00003
38380-08-4	156	2,3,3',4,4',5-HxCB	0.00003
69782-90-7	157	2,3,3',4,4',5'-HxCB	0.00003
52663-72-6	167	2,3',4,4',5,5'-HxCB	0.00003
39635-31-9	189	2,3,3',4,4',5,5'-HpCB	0.00003
Di- ortho*
35065-30-6	170	2,2',3,3',4,4',5-HpCB	0.0001
35065-29-3	180	2,2',3,4,4',5,5'-HpCB	0.00001

[* ] Di-ortho values come from Ahlborg, U.g., et al (1994), which are the WHO 1994 values from Toxic equivalency factors for dioxin-like PCBs: Report on WHO-ECEH and IPCS consultation. December 1993. Chemosphere Volume 28, Issue 6. March 1994. Pages 1049-1067.

Carcinogenic Polycyclic Aromatic Hydrocarbons (cPAH)

Benzo(a)pyrene (B(a)P) is the index chemical for this group of compounds. As of this writing, Health recommends that the following RPFs (EPA, 1993) be employed in the evaluation of cPAH only with respect to carcinogenicity. The sum of adjusted concentrations is referred to as Benzo(a)pyrene toxic equivalents i.e., B(a)P-TE and may be used in the assessment of ingestion, dermal (see EPA, 2004) or inhalation exposure.

Relative Potency Factors for Carcinogenic Polycyclic Aromatic Hydrocarbons

CAS Registry Number	Compound	Benzo(a)pyrene Relative Potency Factor
50-32-8	Benzo(a)pyrene	1
56-55-3	Benzo(a)anthracene	0.1
205-99-2	Benzo(b)fluoranthene	0.1
207-08-9	Benzo(k)fluoranthene	0.01
218-01-9	Chrysene	0.001
53-70-3	Dibenzo(a,h)anthracene	1
193-39-5	Indeno(1,2,3cd)pyrene	0.1

References

EPA, 1993. Provisional Guidance for Quantitative Risk Assessment of Polycyclic Aromatic Hydrocarbons. U.S. Environmental Protection Agency. Research Triangle Park, N.C. EPA/600/R-93/089, July 1993.

EPA, 2004. Risk Assessment Guidance for Superfund Volume I: Human Health Evaluation Manual (Part E, Supplemental Guidance for Dermal Risk Assessment) Final. OSWER 9285.7- 02EP.July 2004.

EPA, 2013. Use of Dioxin TEFs in Calculating Dioxin TEQs at CERCLA and RCRA Sites. United States Environmental Protection Agency. May 2013.

EPA, 2019. United States Environmental Protection Agency. Regional Screening Levels for Chemical Contaminants at Superfund Sites. User's Guide. November 2018 edition. (accessed February 27, 2019).

Van den Berg et al., 2006. The 2005 World Health Organization re-evaluation of human and mammalian toxic equivalency factors for dioxins and dioxin-like compounds. Toxicol Sci 93(2):223-241.

Section F1 TOXICITY EQUIVALENCE FACTORS AND RELATIVE POTENCY FACTORS

Some chemicals are members of the same family or group and have been shown to exhibit similar toxicological properties; however, each chemical may differ in the degree of toxicity (EPA, 2019). In some such instances, a toxicity (sometimes referred to as toxic) equivalency factor (TEF) or relative potency factor (RPF) must be applied to convert the reported concentration of each member of the group to a toxicity (sometimes referred to as toxic) equivalent concentration (TEQ) or to toxic equivalents (TE) relative to the toxicity of the index chemical for the group. The index chemical is assigned a TEF or RPF of 1. Total TEQ or TE can be compared to risk-based values derived for the index chemical or assessed using as any other single chemical in a quantitative risk assessment.

Dioxins, Furans and dioxin-like Polychlorinated Biphenyls (PCBs)

The index chemical for this group is 2,3,7,8-Tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD). As of this writing, Health recommends that the 2005 World Health Organization Toxic Equivalency Factors (Van den Berg et al., 2006) be employed in the evaluation of dioxins, furans and dioxin-like PCBs. These values are also presented in the May 2013 U.S. EPA fact sheet, "Use of Dioxin TEFs in Calculating Dioxin TEQs at CERCLA and RCRA Sites" which references the 2010 U.S. EPA report, "Recommended Toxicity Equivalency Factors (TEFs) for Human Health Risk Assessments of 2,3,7,8-Tetrachlorodibenzo-p-dioxin and Dioxin-Like Compounds" (EPA, 2019). TEFs for Di-ortho PCBs may be obtained from Ahlborg, U.G. et al., 1994 (EPA, 2019). TEFs may be applied to the ingestion, dermal (see EPA, 2004) or inhalation routes of exposure and adjusted values may be used in the assessment of both cancer and noncarcinogenic effects (EPA, 2013). The sum of adjusted concentrations is often referred to as 2,3,7,8-TCDD TEQ.

Dioxin Toxicity Equivalence Factors (EPA, 2019)

CAS Registry Number	Compound	2,3,7,8-TCDD Toxicity Equivalence Factor
Chlorinated dibenzo-p-dioxins
1746-01-6	2,3,7,8-TCDD	1
40321-76-4	1,2,3,7,8-PeCDD	1
39227-28-6	1,2,3,4,7,8-HxCDD	0.1
72918-21-9	1,2,3,6,7,8-HxCDD	0.1
57653-85-7	1,2,3,7,8,9-HxCDD	0.1
35822-46-9	1,2,3,4,6,7,8-HpCDD	0.01
3268-87-9	OCDD	0.0003
Chlorinated dibenzofurans
51207-31-9	2,3,7,8-TCDF	0.1
57117-41-6	1,2,3,7,8-PeCDF	0.03
57117-31-4	2,3,4,7,8-PeCDF	0.3
70648-26-9	1,2,3,4,7,8-HxCDF	0.1
57117-44-9	1,2,3,6,7,8-HxCDF	0.1
72918-21-9	1,2,3,7,8,9-HxCDF	0.1
60851-34-5	2,3,4,6,7,8-HxCDF	0.1
35822-46-9	1,2,3,4,6,7,8-HpCDF	0.01
55673-89-7	1,2,3,4,7,8,9-HpCDF	0.01
39001-02-0	OCDF	0.0003

PCBs
IUPAC No.	Structure
Non- ortho
32598-13-3	77	3,3',4,4'-TetraCB	0.0001
70362-50-4	81	3,4,4',5-TetraCB	0.0003
57465-28-8	126	3,3',4,4',5-PeCB	0.1
32774-16-6	169	3,3',4,4',5,5'-HxCB	0.03
Mono- ortho
32598-14-4	105	2,3,3',4,4'-PeCB	0.00003
74472-37-0	114	2,3,4,4',5-PeCB	0.00003
31508-00-6	118	2,3',4,4',5-PeCB	0.00003
65510-44-3	123	2',3,4,4',5-PeCB	0.00003
38380-08-4	156	2,3,3',4,4',5-HxCB	0.00003
69782-90-7	157	2,3,3',4,4',5'-HxCB	0.00003
52663-72-6	167	2,3',4,4',5,5'-HxCB	0.00003
39635-31-9	189	2,3,3',4,4',5,5'-HpCB	0.00003
Di- ortho*
35065-30-6	170	2,2',3,3',4,4',5-HpCB	0.0001
35065-29-3	180	2,2',3,4,4',5,5'-HpCB	0.00001

[* ] Di-ortho values come from Ahlborg, U.g., et al (1994), which are the WHO 1994 values from Toxic equivalency factors for dioxin-like PCBs: Report on WHO-ECEH and IPCS consultation. December 1993. Chemosphere Volume 28, Issue 6. March 1994. Pages 1049-1067.

Carcinogenic Polycyclic Aromatic Hydrocarbons (cPAH)

Benzo(a)pyrene (B(a)P) is the index chemical for this group of compounds. As of this writing, Health recommends that the following RPFs (EPA, 1993) be employed in the evaluation of cPAH only with respect to carcinogenicity. The sum of adjusted concentrations is referred to as Benzo(a)pyrene toxic equivalents i.e., B(a)P-TE and may be used in the assessment of ingestion, dermal (see EPA, 2004) or inhalation exposure.

Relative Potency Factors for Carcinogenic Polycyclic Aromatic Hydrocarbons

CAS Registry Number	Compound	Benzo(a)pyrene Relative Potency Factor
50-32-8	Benzo(a)pyrene	1
56-55-3	Benzo(a)anthracene	0.1
205-99-2	Benzo(b)fluoranthene	0.1
207-08-9	Benzo(k)fluoranthene	0.01
218-01-9	Chrysene	0.001
53-70-3	Dibenzo(a,h)anthracene	1
193-39-5	Indeno(1,2,3cd)pyrene	0.1

References

EPA, 1993. Provisional Guidance for Quantitative Risk Assessment of Polycyclic Aromatic Hydrocarbons. U.S. Environmental Protection Agency. Research Triangle Park, N.C. EPA/600/R-93/089, July 1993.

EPA, 2004. Risk Assessment Guidance for Superfund Volume I: Human Health Evaluation Manual (Part E, Supplemental Guidance for Dermal Risk Assessment) Final. OSWER 9285.7- 02EP.July 2004.

EPA, 2013. Use of Dioxin TEFs in Calculating Dioxin TEQs at CERCLA and RCRA Sites. United States Environmental Protection Agency. May 2013.

EPA, 2019. United States Environmental Protection Agency. Regional Screening Levels for Chemical Contaminants at Superfund Sites. User's Guide. November 2018 edition. (accessed February 27, 2019).

Van den Berg et al., 2006. The 2005 World Health Organization re-evaluation of human and mammalian toxic equivalency factors for dioxins and dioxin-like compounds. Toxicol Sci 93(2):223-241.

12-012 Code Vt. R. 12-032-012-X