ATSDR - PHA - Great Lakes Chemical Corporation, El Dorado, Union County, Arkansas

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PETITIONED PUBLIC HEALTH ASSESSMENT

GREAT LAKES CHEMICAL CORPORATION
EL DORADO, UNION COUNTY, ARKANSAS

APPENDIX A

APPENDIX B

Exposure Pathway Table

TABLE 1. COMPLETED EXPOSURE PATHWAYS

Pathway
Name
Source Medium Route
of
Exposure
Exposure Elements
Exposure Activities Chemicals
of
Concern

Point
of
Exposure Receptor
Population
Time

Private Well Unknown Groundwater Ingestion, Inhalation, & Dermal Contact Residential
Water Taps
Off-site Users of private well past Drinking, Bathing, & Household Cleaning PAHs (See Appendix C, Table 2)

TABLE 2. POTENTIAL EXPOSURE PATHWAYS

Pathway Name	Source	Medium	Route of Exposure	Exposure Elements			Exposure Activities	Chemicals of Concern
Pathway Name	Source	Medium	Route of Exposure	Point of Exposure	Receptor Population	Time	Exposure Activities	Chemicals of Concern
Ambient Air	GLCC	Ambient Air	Inhalation	Off-site Residential Areas On-site	Residents and GLCC Workers	p,c,f	Outdoor Activities Working	Methyl Bromide
Surface Water	GLCC	Surface Water	Incidental Ingestion and Dermal Contact	Bayou de Loutre Little Cornie Bayou Off-site and On-site	Recreation Enthusiasts and GLCC Workers	p,c,f	Recreation Working	See Appendix C, Table 3
Sediment	GLCC	Sediment	Dermal Contact	Creeks and Drainage Ditches Off-site and On-site	Residents and GLCC Workers	p,c,f	Outdoor Activities Working	Bromides and Chlorides
Key: GLCC = Great Lakes Chemical Corporation c = current; f = future; p = past

APPENDIX C

Environmental Sampling Data

Table 1. Overview of On-Site Groundwater Monitoring Data

Chemical
or Indicator Number of
Observations Maximum
Value

Barium 281 36 ppm

Benzene 5,606 55 ppm

Benzoic acid 47 ND

Bromides 5,838 170,000 ppm

Bromoform 5,559 36 ppm

Calcium 281 37,000 ppm

Chlorides 6,100 360,000 ppm

Dichloropropane 21 1.89 ppm

Ethylene dibromide 6,102 4,500 ppm

Ethylene dichloride 6,086 700 ppm

Hexachloroethane 47 ND

Iron 45 32 ppm

Manganese 45 1.1 ppm

Methyl bromide 47 ND

Methylene chloride 47 0.037 ppm

Phenol(s) 92 ND

Sodium 326 65,000 ppm

Sulfates 5,872 3,723 ppm

Toluene 5,606 47 ppm

Tribromophenol 6,102 5,300 ppm

Trichlorobenzene 29 ND

Notes: As described in the text of this attachment, the data in this table should be viewed as an extensive account of the groundwater sampling at the GLCC Main Plant, but not as a comprehensive account. A maximum concentration of ND means the chemical was never detected.

Table 2. Concentrations of PAHs Detected in one Private Well (1991)

Chemical Maximum
Concentration
(ppb ) RBC-c
(ppb)

Benzo[a]pyrene 66 0.0092

Benz[a]anthracene 112 0.092

Benzo[b]fluoranthene 140 0.092

Benzo[k]fluoranthene 47 0.92

Chrysene 94 9.2

*Note* This private well went out of service in 1968 [2]

ppb parts per billion
RBC-c Risk-Based Concentration (carcinogenic effects)

Table 3. Summary of NPDES Monitoring Data for GLCC

Chemical Range of Detection Limits (ppm) Comparison Value
(ppm) Reference
(refer to cover letter for codes) Number of Samples Analyzed for the Chemical Number of Samples in Which Chemical Was Detected Number of Samples in Which Concentration Exceeded the CV

1,1,1-trichloroethane 0.003--0.01 0.2 MCL 74 0 0

1,1,2,2-tetrachloroethane ^a 0.005--0.01 0.0002 CREG 74 0 0

1,1,2-trichloroethane ^a 0.005--0.01 0.0006 CREG 74 0 0

1,1-dichloroethane 0.004--0.01 NA NA 74 0 0

1,1-dichloroethylene ^a 0.002--0.01 0.00006 CREG 74 0 0

ethylene dibromide ^a 0.005--0.01 0.0000004 CREG 16 7 7

1,2-dichlorobenzene 0.005--0.01 0.6 MCL 60 0 0

ethylene dichloride ^a 0.002--0.01 0.0004 CREG 74 1 1

1,2-dichloropropane 0.005--0.01 0.005 MCL 74 0 0

1,2-trans-dichloroethylene 0.001--0.01 0.1 MCL 74 0 0

1,3-cis-dichloropropylene 0.005--0.01 0.07 MCL 74 0 0

1,3-dichlorobenzene 0.005--0.01 0.6 LTHA 60 0 0

1,3-trans-dichloropropylene ^a 0.005--0.01 0.003 RMEG (Child) 74 0 0

1,4-dichlorobenzene 0.005--0.01 0.075 MCL 60 0 0

2-chloroethylvinyl ether 0.005--0.01 NA NA 74 0 0

acrolein ^a 0.01--0.1 0.005 c-EMEG (Child) 27 0 0

acrylonitrile ^a 0.01--0.1 0.00006 CREG 27 0 0

benzene ^a 0.004--0.01 0.001 CREG 74 0 0

benzyl chloride ^a 0.005--0.1 0.0002 CREG 66 0 0

bromoform 0.004--0.01 0.004 CREG 74 3 3

carbon tetrachloride ^a 0.002--0.01 0.0003 CREG 74 0 0

chlorobenzene 0.005--0.006 100 MCL 37 0 0

chlorodibromomethane ^a 0.003--0.01 0.0004 CREG 74 0 0

chloroethane 0.01--0.02 NA NA 74 0 0

chloroform 0.001--0.01 0.006 CREG 74 1 1

dichlorobromomethane ^a 0.002--0.01 0.0006 CREG 74 0 0

dichlorodifluoromethane 0.005--0.01 1.0 LTHA 18 0 0

dichlorofluoromethane 0.01--0.01 NA NA 11 0 0

epichlorohydrin 0.005--0.1 0.07 DWEL 29 0 0

ethylbenzene 0.005--0.01 0.7 MCL 74 0 0

methyl bromide 0.01--0.02 0.01 LTHA 74 4 4

methyl chloride ^a 0.01--0.02 0.003 LTHA 74 2 2

methylene chloride 0.002--0.01 0.005 CREG/MCL 74 3 1

tetrachloroethylene ^a 0.004--0.01 0.0007 CREG 74 0 0

toluene 0.004--0.01 0.2 i-EMEG (child) 74 2 0

trichloroethylene 0.001--0.01 0.003 CREG 74 0 0

trichlorofluoromethane 0.005--0.01 2.0 LTHA 75 1 0

vinyl chloride ^a 0.005--0.02 0.0002 c-EMEG (child) 74 0 0

NA= not applicable (a comparison value has not been developed for these chemicals in this medium)
^a Range of detection limits exceeds comparison value

Table 4. Distribution of On-site Soil Concentrations of Ethylene Dibromide (EDB), by Depth

Maximum Depth
of Soil Samples Total Number of Samples Distribution of Measured Concentrations Maximum Concentration (ppm)

Non-Detects 1 ppm >1 ppm; 10 ppm >10 ppm

Depth not indicated 74 36 29 2 7 350

Less than 3 feet 57 28 22 2 5 5,800

Greater than 3 feet but less than 10 feet 178 67 55 17 39 8,100

Greater than 10 feet 325 116 111 42 56 6,800

Overall 634 247 217 63 107 8,100

Notes: (1) Shaded cells indicate samples where concentrations exceeded the CREG for ethylene dibromide (or 0.008 ppm).

(2) GLCC monitoring reports generally included a range of soil depths over which each sample was collected. The "maximum depth" in this table refers to the upper end of the depth range for a given soil sample. For example, ERG classified soils sampled over a depth range of 2 to 8 feet in the category of "maximum depth greater than 3 feet but less than 10 feet."

Table 5. Distribution of On-site Soil Concentrations of Ethylene Dichloride (EDC), by Depth

Depth of soil sampling Number of Samples Distribution of Measured Concentrations Maximum Concentration (ppm)

Non-Detects 1 ppm >1 ppm; 8 ppm >8 ppm

Depth not indicated 31 21 8 1 1 29

Less than 3 feet 24 19 5 0 0 0.5

Greater than 3 feet but less than 10 feet 70 43 18 7 2 43

Greater than 10 feet 132 56 30 25 21 140

Overall 257 139 61 33 24 140

Notes: (1) Shaded cells indicate samples where concentrations exceeded the CREG for ethylene dichloride (8 ppm).

APPENDIX D

Evaluation of Environmental Contamination and Potential Exposure Pathways Methodology

Quality Assurance

In preparing this report, ATSDR relied on the information provided in the referenced documents and by contacts with the United States Environmental Protection Agency, Arkansas Department of Environmental Quality, Arkansas Department of Health, Union County Department of Health, and community members. ATSDR assumes that adequate quality assurance and control measures were taken during chain-of-custody, laboratory procedures, and data reporting. The validity of the analyses and conclusions drawn in this document are determined by the availability and reliability of the information.

Human Exposure Pathway Evaluation and the use of ATSDR Comparison Values

ATSDR assesses a site by evaluating the level of exposure in potential or completed exposure pathways. An exposure pathway is the way chemicals may enter a person's body to cause a health effect. It includes all the steps between the release of a chemical and the population exposed: (1) a chemical release source, (2) chemical movement, (3) a place where people can come into contact with the chemical, (4) a route of human exposure, and (5) a population that could be exposed. In this assessment, ATSDR evaluates chemicals in environmental media that people living in nearby residences may come into contact with.

Data evaluators use comparison values (CVs), which are screening tools used to evaluate environmental data that is relevant to the exposure pathways. Comparison values are concentrations of contaminants that are considered to be safe levels of exposure. Comparison values used in this document include ATSDR's environmental media evaluation guide (EMEG) and cancer risk evaluation guide (CREG). Comparison values are derived from available health guidelines, such as ATSDR's minimal risk levels and EPA's cancer slope factor.

The derivation of a comparison value uses conservative exposure assumptions, resulting in values that are much lower than exposure concentrations observed to cause adverse health effects; thus, insuring the comparison values are protective of public health in essentially all exposure situations. That is, if the concentrations in the exposure medium are less than the CV, the exposures are not of health concern and no further analysis of the pathway is required. However, while concentrations below the comparison value are not expected to lead to any observable health effect, it should not be inferred that a concentration greater than the comparison value will necessarily lead to adverse effects. Depending on site-specific environmental exposure factors (for example, duration of exposure) and activities of people that result in exposure (time spent in area of contamination), exposure to levels above the comparison value may or may not lead to a health effect. Therefore, ATSDR's comparison values are not used to predict the occurrence of adverse health effects.

The comparison values used in this evaluation are defined as follows: The CREG is a concentration at which excess cancer risk is not likely to exceed one case of cancer in a million persons exposed over a lifetime. The CREG is a very conservative CV that is used to estimate cancer risk. Exposure to a concentration equal to or less than the CREG is defined as an insignificant risk and is an acceptable level of exposure over a lifetime. The risk from exposure is not considered as a significant risk unless the exposure concentration is approximately 10 times the CREG and exposure occurs over several years. The EMEG is a concentration at which daily exposure for a lifetime is unlikely to result in adverse noncancerous effects.

Selecting Contaminants of Concern

Contaminants of concern (COCs) are the site-specific chemical substances that the health assessor selects for further evaluation of potential health effects. Identifying contaminants of concern is a process that requires the assessor to examine contaminant concentrations at the site, the quality of environmental sampling data, and the potential for human exposure. A thorough review of each of these issues is required to accurately select COCs in the site-specific human exposure pathway. The following text describes the selection process.

In the first step of the COC selection process, the maximum contaminant concentrations are compared directly to health comparison values. ATSDR considers site-specific exposure factors to ensure selection of appropriate health comparison values. If the maximum concentration reported for a chemical was less than the health comparison value, ATSDR concluded that exposure to that chemical was not of public health concern; therefore, no further data review was required for that chemical. However, if the maximum concentration was greater than the health comparison value, the chemical was selected for additional data review. In addition, any chemicals detected that did not have relevant health comparison values were also selected for additional data review.

Comparison values have not been developed for some contaminants, and, based on new scientific information other comparison values may be determined to be inappropriate for the specific type of exposure. In those cases, the contaminants are included as contaminants of concern if current scientific information indicates exposure to those contaminants may be of public health concern.

The next step of the process requires a more in-depth review of data for each of the contaminants selected. Factors used in the selection of the COCs included the number of samples with detections above the minimum detection limit, the number of samples with detections above an acute or chronic health comparison value, and the potential for exposure at the monitoring location.

APPENDIX E

Public Comments and ATSDR's Response

This appendix contains the comments received during the public comment period for GLCC and ATSDR's response to those comments. The comments have been numbered and are in italic with the response directly below each comment.

A citizen wrote to ATSDR that they disagreed with the findings and are no longer interested in this public health assessment.

These comments have been noted and included in ATSDR's official site file.

The official plant name and location are incorrect. The correct title is "Great Lakes Chemical Corporation El Dorado Plant".

This change has been implemented in ATSDR's database and in the public health assessment.

On page 5, insert the following sentence: The Arkansas Department of Environmental Quality (ADEQ) monitored the GLCC property line and Parkers Chapel (a nearby residential community) weekly for methyl bromide from June 2, 1995 to May 27, 1996. Most analytical results were below the EPA risk-based concentration for ambient air".

The ambient air sampling event referred to in this comment has been evaluated and included in the public health assessment.

Page 6; page 7;- 16,000 ppm looks high by 10x.

ATSDR re-evaluated the sampling summary and 16,000 ppm is correct.

Table of Contents

Agency for Toxic Substances and Disease Registry, 1825 Century Blvd, Atlanta, GA 30345
Contact CDC: 800-232-4636 / TTY: 888-232-6348

Department of Health and Human Services

Chemical or Indicator	Number of Observations	Maximum Value
Barium	281	36 ppm
Benzene	5,606	55 ppm
Benzoic acid	47	ND
Bromides	5,838	170,000 ppm
Bromoform	5,559	36 ppm
Calcium	281	37,000 ppm
Chlorides	6,100	360,000 ppm
Dichloropropane	21	1.89 ppm
Ethylene dibromide	6,102	4,500 ppm
Ethylene dichloride	6,086	700 ppm
Hexachloroethane	47	ND
Iron	45	32 ppm
Manganese	45	1.1 ppm
Methyl bromide	47	ND
Methylene chloride	47	0.037 ppm
Phenol(s)	92	ND
Sodium	326	65,000 ppm
Sulfates	5,872	3,723 ppm
Toluene	5,606	47 ppm
Tribromophenol	6,102	5,300 ppm
Trichlorobenzene	29	ND

Chemical	Maximum Concentration (ppb )	RBC-c (ppb)
Benzo[a]pyrene	66	0.0092
Benz[a]anthracene	112	0.092
Benzo[b]fluoranthene	140	0.092
Benzo[k]fluoranthene	47	0.92
Chrysene	94	9.2

Chemical	Range of Detection Limits (ppm)	Comparison Value (ppm)	Reference (refer to cover letter for codes)	Number of Samples Analyzed for the Chemical	Number of Samples in Which Chemical Was Detected	Number of Samples in Which Concentration Exceeded the CV
1,1,1-trichloroethane	0.003--0.01	0.2	MCL	74	0	0
1,1,2,2-tetrachloroethane ^a	0.005--0.01	0.0002	CREG	74	0	0
1,1,2-trichloroethane ^a	0.005--0.01	0.0006	CREG	74	0	0
1,1-dichloroethane	0.004--0.01	NA	NA	74	0	0
1,1-dichloroethylene ^a	0.002--0.01	0.00006	CREG	74	0	0
ethylene dibromide ^a	0.005--0.01	0.0000004	CREG	16	7	7
1,2-dichlorobenzene	0.005--0.01	0.6	MCL	60	0	0
ethylene dichloride ^a	0.002--0.01	0.0004	CREG	74	1	1
1,2-dichloropropane	0.005--0.01	0.005	MCL	74	0	0
1,2-trans-dichloroethylene	0.001--0.01	0.1	MCL	74	0	0
1,3-cis-dichloropropylene	0.005--0.01	0.07	MCL	74	0	0
1,3-dichlorobenzene	0.005--0.01	0.6	LTHA	60	0	0
1,3-trans-dichloropropylene ^a	0.005--0.01	0.003	RMEG (Child)	74	0	0
1,4-dichlorobenzene	0.005--0.01	0.075	MCL	60	0	0
2-chloroethylvinyl ether	0.005--0.01	NA	NA	74	0	0
acrolein ^a	0.01--0.1	0.005	c-EMEG (Child)	27	0	0
acrylonitrile ^a	0.01--0.1	0.00006	CREG	27	0	0
benzene ^a	0.004--0.01	0.001	CREG	74	0	0
benzyl chloride ^a	0.005--0.1	0.0002	CREG	66	0	0
bromoform	0.004--0.01	0.004	CREG	74	3	3
carbon tetrachloride ^a	0.002--0.01	0.0003	CREG	74	0	0
chlorobenzene	0.005--0.006	100	MCL	37	0	0
chlorodibromomethane ^a	0.003--0.01	0.0004	CREG	74	0	0
chloroethane	0.01--0.02	NA	NA	74	0	0
chloroform	0.001--0.01	0.006	CREG	74	1	1
dichlorobromomethane ^a	0.002--0.01	0.0006	CREG	74	0	0
dichlorodifluoromethane	0.005--0.01	1.0	LTHA	18	0	0
dichlorofluoromethane	0.01--0.01	NA	NA	11	0	0
epichlorohydrin	0.005--0.1	0.07	DWEL	29	0	0
ethylbenzene	0.005--0.01	0.7	MCL	74	0	0
methyl bromide	0.01--0.02	0.01	LTHA	74	4	4
methyl chloride ^a	0.01--0.02	0.003	LTHA	74	2	2
methylene chloride	0.002--0.01	0.005	CREG/MCL	74	3	1
tetrachloroethylene ^a	0.004--0.01	0.0007	CREG	74	0	0
toluene	0.004--0.01	0.2	i-EMEG (child)	74	2	0
trichloroethylene	0.001--0.01	0.003	CREG	74	0	0
trichlorofluoromethane	0.005--0.01	2.0	LTHA	75	1	0
vinyl chloride ^a	0.005--0.02	0.0002	c-EMEG (child)	74	0	0

Maximum Depth of Soil Samples	Total Number of Samples	Distribution of Measured Concentrations				Maximum Concentration (ppm)
Maximum Depth of Soil Samples	Total Number of Samples	Non-Detects	1 ppm	>1 ppm; 10 ppm	>10 ppm	Maximum Concentration (ppm)
Depth not indicated	74	36	29	2	7	350
Less than 3 feet	57	28	22	2	5	5,800
Greater than 3 feet but less than 10 feet	178	67	55	17	39	8,100
Greater than 10 feet	325	116	111	42	56	6,800
Overall	634	247	217	63	107	8,100

Depth of soil sampling	Number of Samples	Distribution of Measured Concentrations				Maximum Concentration (ppm)
Depth of soil sampling	Number of Samples	Non-Detects	1 ppm	>1 ppm; 8 ppm	>8 ppm	Maximum Concentration (ppm)
Depth not indicated	31	21	8	1	1	29
Less than 3 feet	24	19	5	0	0	0.5
Greater than 3 feet but less than 10 feet	70	43	18	7	2	43
Greater than 10 feet	132	56	30	25	21	140
Overall	257	139	61	33	24	140