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Public Health Assessment
Ciba-Geigy Corporation
(Dover Township) Toms River, New Jersey
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Environmental Contamination
Groundwater: On-site and Off-site Monitoring Wells
Many monitoring wells have been installed on and off the CGC site for the purpose of characterizing, groundwater contamination and flow. Monitoring wells are screened in elements of the Upper Sand and Lower Sand Aquifers. The groundwater Remedial Investigation (RI) for Operable Unit I indicated that there were multiple on-site sources of groundwater contamination, since several of the original lagoons and other disposal areas were unlined (NUS, 1988a).
In the USEPA Remedial Investigation, numerous contaminants were identified in groundwater under the CGC site, including VOCS, and metals- As summarized in the 1988 ATSDR Public Health Assessment, on-site monitoring wells contained high levels of the following VOCs (maximum value noted); acetone (74,500 µg/l), benzene (3,950 gg/1), chlorobenzene (26,000 µg/l), chloroform (4,400 µg/l), toluene (14,000
µg/l), tetrachloroethylene (12,000 µg/l), trichloroethylene (25,000 µg/l) and vinyl chloride (89 µg/l). On-site monitoring wells also contained elevated levels of metals (maximum value noted): cadmium (318 µg/l), chromium (318 µg/l), lead (255 µg/l) and mercury (12 µg/l). Monitoring of off-site groundwater was accomplished using existing residential wells (see "Groundwater: Residential Private Wells Adjacent to the CGC Site" section below). These wells
(used for irrigation) showed that groundwater contaminants had migrated from the CGC site below adjacent residential areas (NUS, 1988d).
In accordance with USEPA guidelines, only those chemicals that were on the Hazardous Substances List (HSL) were taken under consideration to be chemicals of concern (USEPA, 1986). The chemicals were then evaluated for toxicity and assigned an "indicator" score. This process resulted in the selection of 11 individual species as indicator chemicals. These chemicals were subsequently considered in the quantitative baseline (i.e., no action) risk assessment
performed for the USEPA (NUS, 1988c). The indicator chemicals which were selected were those known to have been used and disposed at the site, were found in monitoring wells or in private off-site wells, and had high "indicator" scores. The selected indicator chemicals were intended to represent the numerous other contaminants potentially present in the groundwater, but for which
standard or routine analytical methods were not available (for example, azo dyes, resins, or their reagent, such as epichlorohydrin, aniline, anthraquinone, benzidine, or their substituted analogs, hydrochlorides, or sulfonic acid salts). The selected indicator chemicals were:
Groundwater chemicals of concern (for potential carcinogenic risk): arsenic, benzene, chloroform, 1,2-dichloroethane, trichloroethylene, tetrachloroethylene.
Groundwater chemicals of concern (for potential non-carcinogenic effects): arsenic, barium, cadmium, chlorobenzene, nickel, 1,2,4-trichlorobenzene.
Between 1994 and 1996, four semi-annual sampling and monitoring plan (SAMP) events were conducted (Eckenfcldcr, 1996). The "SAMP 4" monitoring events evaluated approximately 133 on- and off-site monitoring wells screened in four aquifer elements; the Primary Cohansey (63 wells), the Lower Cohansey (26 wells), the Kirkwood No. 1 (36 wells), and the Lower Sand (8 wells). Contamination of groundwater by various metals (including cadmium, lead, and mercury)
and VOCs (including benzene, chlorobenzene, dichlorobenzene, chlorotoluene, dichloroethylene, methylene chloride, tetrachloroethylene, trichlorobenzene, trichloroethylene, and trichlornpropane) was found in both on- and off-site monitoring wells which are screened in the Primary Cohansey and Lower Cohansey elements of the Upper Sand Aquifer. Contamination of these aquifer elements has been found in several of the monitoring wells east of Toms River.
No contamination of the Lower Sand Aquifer by VOCs or metals was found. Figure 6 presents the estimated extent of contamination by total VOCs which were reported in SAMP 4 to be present in the Primary Cohansey and Lower Cohansey aquifer elements, respectively, in 1996.
Longer term (annual) monitoring of the groundwater in the vicinity of the CGC site is being conducted under the provisions of the Site Wide Monitoring Program of the Long Term Monitoring Plan (CI13A, 1995). The results of the First Annual Report (Eckenfelder, 1997) were similar to those reported in SAMP 4; 22 of the wells reported in SAMP 4 were the same data reported included in the First Annual Report. Table 3 shows the contaminants which were found
in samples taken during January 1998 as part of the Second Annual Report -in several on-site monitoring wells located near known source areas (Eckenfelder, 1999). As indicated, the concentrations of numerous chlorinated hydrocarbons found in these wells which sample both the Primary and Lower Cohansey aquifers exceed drinking water MCLs and the ESD-mandated cleanup criteria.
In August and September 1997, NJDHSS (in cooperation with Ciba-Geigy) conducted a separate sampling of 31 monitoring wells on- and off-site which were screened in the Upper Sand (Primary Cohansey, Lower Cohansey and Kirkwood No. 1 elements) and Lower Sand aquifers. The nature and extent of groundwater contamination observed was consistent with previous investigations. The data from this sampling episode will be presented in a separate summary document.
Groundwater: Extraction Wells
The ESD list of contaminants has also been analyzed quarterly in the untreated, blended water from the 43 extraction welts (CI03A, 1998a). Table 4 shows the contaminants found in the untreated, extracted water during the period January through March 1999 (CIBA, 1999a). As with the individual monitoring wells, the blended extracted groundwater also contains numerous substances, including many chlorinated hydrocarbons, which exceed cleanup criteria or MCLS.
Extracted water is treated to meet levels set in the ESD.
Groundwater: Residential Private Wells Adjacent to the CGC Site
In the period 1985 to 1988, several private residential wells in the Cardinal Drive/Oak Ridge Parkway area to the southeast of the CGC site (reported to be used for irrigation and/or non-potable domestic purposes at the time) were found to have been contaminated with VOCs (NUS, 1988a). These VOCs included (maximum level noted): chloroform (251 µg/l), trichloroethylene (38 µg/l), benzene (100 µg/l),
tetrachloroethylene (58 µg/l), chlorobenzene (79 µg/l) and xylenes (8 µg/l) (ATSDR, 1988a; NUS, 1988a). According to the USEPA, 15 private residential wells (used for irrigation) in the northern portion of the Cardinal Drive/Oak Ridge Parkway area were identified and seated between 1996 and 1991.
Other residential areas to the southwest and northeast of the CGC site were also sampled and tested during this time. Lead and mercury above drinking water MCLs or action levels were detected in the Coulter Street area and other areas, but the pattern of detections did not suggest the CCIC site as a source of the contaminants (NUS, 1999d).
On-site Source Areas
Characterization of the on-site source areas (Operable Unit 2) have been addressed in a Remedial Investigation (CDM, 1993 a) and Feasibility Study (CIBA, 1999b). Approximately 20 source areas have been shown to contain metals, VOCs and SVOCS. The USEPA has selected several indicator chemicals for on-site source area contamination:
Source area chemicals of concern: chlorobenzene, 2-chlorotoluene, 1,2-dichlorobenzene, naphthalene, nitrobenzene, tetrachloroethylene, trichloroethylene, 1,2,4-tiichlorobenzene, 1,2,3-trichloropropane, toluene, phenanthrene, ethylbenzene, 1,2-dichloroethylene, arsenic, lead and mercury
The indicator chemicals have been used as the basis for source area surface soil pathways analysis and baseline source area risk assessment documents (CDM, 1993d; CDM 1993e). Additional documents describe the hundreds of surface and subsurface contaminants which have been identified and their toxicological characteristics (CDM, 1994a). Several hundred unidentified species (or tentatively identified compounds; i.e., TICS) have also been found in samples
taken from on-site property (see next section).
Studies of Non-Target Compounds in On-site Soils
In addition to the indicator chemicals, the USEPA has investigated the presence of additional species, primarily organic dyes and their reagents, in surface and subsurface soils on the CGC site (CDM, 1993f, 1994a). The majority of these samples were taken in the production area and in the east equalization basin. Many non-target compounds (NTCS) have been found in the approximately 200 surface soil samples taken on the CGC site. Some of these NTCs have
been tentatively identified (TICS) but not quantified. Approximately 147 NTCs (63 of which have been identified by CAS Registry Number) have been detected in surface soils (CDM, 1993f-, CDM, 1994a). Among the TICs are the following: anthraquinone, aminoanthraquinone, chloroanthraquinone, dihydroxyanthraquinone and several other substituted variants; aniline and substituted species; 1-methyl-2-pyrrolidone; benzanthrone; and pentachlorothioanisole.
In addition, 378 NTCs (157 of which have been identified by CAS Registry Number) have been detected in 560 subsurface soil borings (of which 216 samples were taken in the production area, 60 in the drum disposal area, and 50 in the west equalization basin) taken on the CGC site (CDM, 1994b; CDM, 1994c). As with the surface soils, among the TICs found in subsurface soils arc anthraquinone (and many substituted variants) and benzanthrone. A re-analysis of
several original sample results described approximately 108 NTCs (of which at least 66 were tentatively identified, including substituted anthraquinones and beizaiithrone) that were present in on-site surface and subsurface soils (DS, 1997).
Although it should not be assumed that the dyes and intermediates identified in on-site soils are also present in the groundwater, the possibility does exist that partition between soil and aqueous phases and transport of these species may result in some of them being present in the groundwater beneath the CGC site. Many of the dyes and reagents were in fact used in the form of their (water-soluble) hydrochloride and
sulfonic acid salts. Few of these compounds have been analyzed for in on- or off-site groundwater. Unfortunately, standard analytical methods for low-level quantitative detection of many organic dyes and their reagents in aqueous media are not available.
Surface Water and Sediments: The Toms River
Surface Water
The practice at the Toms River Plant of discharging process wastewater into the Toms River prior to the use of the ocean outfall pipeline in 1966 had a direct, negative impact on the water quality of the Toms River. New Jersey Department of Health inspection reports for June 1962 and October 1963 (NJDOH, 1962; NIDOU, 1963) indicate discharges to the Toms River resulted in conspicuous coloration (red/brown), noticeable odors, increased biological oxygen demand,
and the presence of "phenolic substances" at 0.29 parts per million (ppm, or milligrams per liter). For the period of October 1965 to January 1966, the Toms River Chemical Company discharged diazotizable amines (measured as aniline) to the Toms River at the rate of 530 to 1,210 pounds per day (TRCC, 1965). Nitrobenzene was also discharged into the Toms River by the Toms River Plant, for example, approximately 26,370 pounds of nitrobenzene were reported as discharged
during April 1966 (TRCC, 1966c). After installation of the outfall pipeline in late 1966, direct discharge of liquid wastes to the Toms River was terminated. However, in January 1969, the Toms River Chemical Company estimated that approximately 200,000 gallons of liquid wastes per day continued to infiltrate the Toms River from sludge lagoons and disposal areas (NUS, 1988a; TRCC, 1969).
Sediments
Historically, the impact of the CGC site upon sediments of the Toms River has been reported by the USEPA to have resulted in increases 'in the presence of metals and VOCS, and a decrease in the number and diversity of macro invertebrates and other pollution intolerant species. However, the termination of release of untreated process wastes has since resulted in an improvement in the quality of surface waters and sediments of the Toms River (CDM, 1994d).
In September 1996, NJDHSS obtained samples of sediment at four locations (at depths of 0-6" and 6-12") along the Toms River downstream of the Ciba-Geigy plant, and at five locations along the intermittent stream adjacent to Long Swamp Road downstream from known breaks in the outfall pipeline. The locations of these samples are also shown in Figure 7. The results of analyses of these l8 samples are compared with NJDEP and Ontario Ministry of Environment and Energy
guidelines in Table 6 (NJDHSS, 1997a). There are no established human health-based standards for contaminants in aquatic sediments; however, the concentrations of heavy metals and SVOCs found in these samples were not unusual for aquatic sediments in urban areas.
Community Water Supply Wells
The Toms River Chemical Company's (TRCC) practice of discharging process wastes directly to the Toms River prior to 1966 affected community water supply wells of the Toms River Water Company (TRWC, later United Water Toms River). Three shallow supply wells (#13, #14, and #18) of the Holly Street well field (located near the banks of the Toms River approximately 1.4 miles downstream of the wastewater discharge point; see inset) were found to be contaminated in the mid-I960s.
In a "Water Analysis Record" from March 1965, raw water from Well #13 was described as having a distinct odor and as being visibly contaminated with "trade wastes (dye)." This document further indicated that water from Well #13 was treated with chlorine at 8 ppm to reduce
coloration prior to distribution ('I'RWC, 1965). TRCC analyses of Holly Street well field wells from May through October 1966 showed contamination of Wells #13, #14,
and #18 with "diazotizables" (aniline-based dyes, measured as aniline) at concentrations ranging up to 160 µg/l (TRCC, 1966a; USEPA, undated). Nitrobenzene was also reported at concentrations up to 17 µg/l (TRCC, 1966b).
In 1965 and 1966, the Holly Street Well Field was a major source of water for the TRWC community water supply (other sources included well # 15 at Brookside Avenue, and wells at Anchorage and Saver Bay). Holly Street Well # 13 was permitted in 1946 and reported as sealed in 1967 (Wayne, 1955; UWTR, undated). Well #14 was used until 1975 and well #18 was used until 1980. Both wells #14 and #18 were sealed in 1983.
Airborne Contaminants
There were community complaints of odors related to emissions and site runoff related to the Toms River Plant throughout its period of operation. In September 1986, ambient air was sampled and analyzed (Radian, 1986) as a result of complaints of odors in the marshland areas of Winding River Park on the east side of the Toms River. Samples showed the presence of several VOCs used at the Toms River Plant which appear to be
above background (maximum level noted): benzene (3.2 micrograms per cubic meter, or µg/m3), chlorobenzene (16.5 µg/m3), chloroform (15.1 µg/m3), toluene (180 µg/m3 ) tetrachloroethylene (8.8 µg/m3) and trichloroethylene (58 µg/m3).
Soil gas VOCs had been measured in the Cardinal Drive/Oak Ridge Parkway area (11 ppm total VOCs) and in the Winding River park (1,625 ppm total VOCs)(Weston,1991). However, soil gas and flux chamber measurements taken later at residences in the Cardinal Drive/Oak Ridge Parkway area showed low to no detectable levels of VOCS, indicating that the concentrations of these contaminants were not at levels of public health concern at that time (CDM, 1993b; CDM, 1993c).
Stack emissions from the Toms River Plant were regulated through permits by the NJDEP. A review of the USEPA Toxic Release Inventory (TRI) data show that stack emissions from the CGC in the period 1987 to 1990 plant included: acetone, ammonia, copper compounds, epichlorohydrin, formaldehyde, methanol, methyl ethyl ketone, methyl isobutyl ketone, 4,4'-methylenedianiae, n-butyl alcohol, o-cresol, toluene, and xylenes.
Uncontrolled Discharges from the Outfall Pipeline
Prior to 1966, process wastewater from CGC was discharged directly to the Toms River. However, during the 25 year period between 1966 and 1991, treated wastewater was discharged to the Atlantic Ocean through a 10 mile long pipeline (28 " outside diameter, coated internally and externally with coal tar enamel). The underground pipeline ran predominantly along Mapletree Avenue and Bay Avenue, then under Barnegat Bay and Ortley Beach (an area of Dover Township located on a barrier island)
before emptying approximately 3,500 feet out into the Atlantic Ocean (Figure 7). Use of the outfall pipeline for disposal of treated wastewater was terminated in 1991. The section of the pipeline from the CGC site to Bay and Vaughn Avenues was filled with water and closed in 1992. In 1994 the pipeline section which extended into the Atlantic Ocean was removed, and the section from Bay and Vaughn Avenues and the barrier island was transferred to the Ocean County Utilities Authority to be used as a supplemental sanitary sewer line.
Between 1984 and 1989, several incidents of uncontrolled discharge of treated wastewater occurred as a result of malfunctioning valves or from inadvertent construction damage to the pipeline. According to the NJDEP, potentially contaminated soils were removed and replaced with clean soils when the pipeline breaks were repaired. After an uncontrolled pipeline discharge in 1985, a pipeline monitoring program was proposed (AWARE, 1985).
Six monitoring wells were installed by the CGC along the pipeline in 1987, and monitoring was started in 1988. Elevated concentrations of chromium and lead were found in samples from four of the six installed monitoring wells over the course of several sampling episodes between 1988 and 1993 (CIBA 1997), largely due to particulate matter in the samples. Forty-five private residential wells were sampled by the CGC at different times between 1987 and 1994. Samples from several private
wells contained low levels of VOCs (below applicable MCLS); chromium, copper, lead and mercury were detected in other private well samples, in some cases above the applicable MCLs (CIBA,1996). The sources of these substances are uncertain, but the geographic pattern of detected contaminants does not suggest that the outfall pipeline breaks were a likely source. Lead and copper have been commonly found to be present in private residential well water samples, most likely due to corrosion
of plumbing by acidic groundwater. Mercury has also been frequently found in private residential wells in Dover Township and elsewhere in southern New Jersey.
ATSDR/NJDHSS Exposure Investigation
In September 1996, the NJDHSS and ATSDR collected and analyzed 18 surface soil samples that were taken at four locations along Bay Avenue in the vicinity of known outfall pipeline breaks (Figure 7)(NJDHSS, 1997a). The results of these analyses are given in Table 5. As shown, none of these surface soil samples exceed soil Comparison Values for metals and organic chemicals. A full summary of these data will be included in a separate document.
From February to May 1997, the NJDHSS and ATSDR sampled 54 private wells located throughout Dover Township for chemical and radiological testing (NJDHSS, 1997b; NJDHSS, 1997c). Ten of the 54 private wells were located near the CGC site (Figure 8); chemical testing results are shown in Table 7. None of these ten wells showed any contaminants which exceed drinking water MCLs or that were considered site-related. Similarly, 14 of the 54 private wells were within approximately
one-quarter mile of the route of the former outfall pipeline. None of these wells exhibited contaminants that could be considered pipeline-related. Chromium was below the limit of detection in all 54 sampled wells.
Several of the 54 wells located in Dover Township were found to have elevated levels of lead and mercury. Low levels of chloroform were found in several of the tested wells. There was no pattern which would indicate that CGC or the outfall pipeline is the source of these contaminants. Gross alpha activity in excess of the MCL was found in many of the sampled wells, attributable to naturally occurring radium species. A complete summary and evaluation of the private well data generated during the Exposure
Investigation conducted by the NJDHSS and the ATSDR will be presented in a separate document.
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