PRELIMINARY PUBLIC HEALTH ASSESSMENT
NEWPORT, NEW CASTLE COUNTY, DELAWARE
The Koppers Company, Inc. (Newport Plant) wood treatment plant is a National Priorities List(NPL) site located in Newport, New Castle County, Delaware (figure 1). On-site soils andsediments are contaminated with polycyclic aromatic hydrocarbons (PAHs), by-products of woodtreatment processes. The site also contains concentrations of metals (i.e., arsenic, barium,cadmium, chromium, lead, manganese, mercury, and vanadium) in soil and sediment that exceedcomparison levels.
Soil, sediment, and water have been sampled although only the results of the soil and sedimentanalyses are useable. The water samples could not be evaluated because of quality analysis andquality control problems. The most likely exposure pathways are ingestion of soil, sediment, andgroundwater, and ingestion of terrestrial and aquatic biota. Exposure scenarios are discussed inthe Potential Exposure Pathways section of this Preliminary Public Health Assessment.
Based on the available information, this site is considered to be an indeterminate public healthhazard. The limited available data do not allow a determination of whether persons are being,have been, or will be exposed to levels of contamination from this site that would be expected tocause adverse health effects. Preliminary results indicate that adverse health effects may bepossible due to potential exposure from ingestion of sediments and soils contaminated withPAHs, arsenic, cadmium, lead, and other possible unidentified chemicals.
Some PAHs have caused cancer in laboratory animals that have ingested, breathed, or had PAHsapplied to their skin. In addition, reports indicate that some PAHs may cause cancer in humans.
The ATSDR Health Activities Recommendation Panel (HARP) has evaluated the Koppers Co.,Inc. site to determine the need for follow-up health activities. Due to insufficient sitecharacterization, no follow-up health activities are proposed at this time.
Koppers Company, Inc. (Koppers) operated a wood treatment facility from 1929 to 1971 on a285 acres site (figure 2) which was part of a 317 acre area. During this time railroad ties andtelephone poles were pressure injected with creosote or a mixture of number 2 fuel oil andpentachlorophenol, which resulted in the release of wood treatment chemicals into theenvironment (1, 2).
Prior to 1929, the property was owned by several families. Various subsidiaries of Koppersoperated the wood treatment facility until 1971 when the property was sold to E.I. DuPont deNemours (DuPont). As part of the sales agreement, Koppers removed railroad rails andunknown chemicals from process tanks while DuPont removed existing structures. No recordswere kept on what types of operations were housed in the structures. In 1984, DuPont soldDuPont Ciba Geigy, which consisted of the pigment plant and 22 surrounding acres, to CibaGeigy. DuPont owns and operates the DuPont Holly Run Plant which produces chromiumdioxide, a metal, and Ciba Geigy owns and operates the Ciba Geigy Plant, which manufacturesquinocridone, a red pigment. Both manufacturing plants are located on property adjacent to the285 acre site (see figure 2).
DuPont still owns the property but has not used the site since the removal of the structures;however, in 1974, the New Castle County Department of Public Works constructed a sewagetreatment plant enclosed in a single building on the Koppers site. The sewage treatment plantclosed in 1977 and a new treatment plant was constructed north of Penn Central railroad tracksadjacent to the site. Doors and windows at the closed sewage facility are locked with pad locksand a fence surrounds the facility; however, the gate for the fence is always left open (see figure 1).
The official entrance to the site is along Access Road. Access to the road is controlled by a guardat the main entrance to the Ciba Geigy Plant located east of the site. One must drive throughportions of the Ciba Geigy Plant and the DuPont Holly Run Plant to enter the site. Since theclosed sewage treatment facility is the only fenced area on the site it is possible on foot or by boatto enter the site by crossing the Christina River, White Clay Creek, Hershey Run, and the wetlandareas. The most likely entry point is by crossing the railroad tracks from the residential area tothe north (see figure 2). "No Trespassing" signs are posted near all roads and trails entering thesite (3).
On October 17, 1990, Paul Racette, Agency for Toxic Substances and Disease Registry(ATSDR) Region III; Dennis Miller, ATSDR subcontractor from Oak Ridge NationalLaboratory; Andrew Sochanski, Environmental Protection Agency (EPA) Regional ProgramManager; Leslie Brunker, EPA Region III; the DuPont Environmental Project Manager; and arepresentative from the Delaware Bureau of Environmental Health conducted an inspection ofthe Koppers site. The DuPont Environmental Project Manager, who had been on the sitepreviously, provided information about the site's history and operations, as well as DuPont'sinvolvement with the site. He also provided information on the location of nearby private wells(3).
During the visit we saw the main areas of contamination, although it was difficult to see theentire site because of the dense vegetation. We noted several areas that may be sources or sinksof contamination. One such area is a building foundation that served as a railroad loading dock. A surface seep, consisting of a long narrow pool of black creosote-like liquid, was observedalong the length of this foundation. The seep drains and collects at the southwest corner of thisstructure. Piles of vegetation-covered railroad ties were noted across the site. Another area wasthe old fire pond located near the northwest corner of the site. The pond, which was used to storewater for fire suppression, is now only a depression where large trees and dense vegetation grow.
Some areas on the site that were identified in various documents as possible contaminant sourcescould not be observed because of the dense vegetation, e.g., a drainage ditch containing anunidentified liquid located adjacent to the eastern boundary of the site and an opening covered byboards located on the eastern portion of the site (see figure 2).
We found evidence of hunters on the site at different locations. Spent shells were found near theseep at the building foundation and near the old fire pond. We also discovered a deer blind nearthe old fire pond. At another location a target with several bullet holes in it was nailed to astump.
We inspected adjacent off-site properties during the site tour. Contrary to documentation thatstated most buildings along Old Airport Road are residences, the majority of buildings are usedfor small businesses such as junk/salvage yards and auto mechanic shops.
The Koppers site is located 4.5 miles inland from the Atlantic Ocean in the City of Newport,Delaware, which has a population of 1,240. 19,500 people reside within a 3-mile radius. Thetown of Christiana is located approximately 3-1/2 miles southwest of the site.
The Koppers site is bounded by rivers, creeks, and industrial complexes. To the east, it isbounded by the Christina River and two plants, Ciba Geigy Plant and DuPont Holly Run Plant. The site is bounded to the south by White Clay Creek, and to the west by fresh-water wetlandsand Hershey Run Creek. The southwest portion of the site is wooded. The Pennsylvania Centralelectric commuter train line borders the site to the north. A warehouse district is located north ofthe railroad tracks.
The residential area nearest to the site is north beyond the warehouse district, approximately onefourth of a mile away from the site boundary in the City of Newark. The City of Newark has apopulation comprised of a few hundred lower-middle to middle income households. Of thesepeople, eighty-eight percent are Caucasian, ten percent are Black, and two percent are Hispanic(4). Approximately 100 people live or work in a small residential and business area locatedacross the Christina River three-fourths of a mile south east of the site along Old Airport Road. Businesses along Old Airport Road consist of salvage yards and car mechanic shops.
Recreational activities off the site include fishing, boating, and swimming in the Christina River. In addition, trespassers hunt and hike on the site. There are no known public or private boatlaunches north of the James Street Bridge. The James Street Bridge crosses over the ChristinaRiver adjacent to the Ciba Geigy Plant east of the site. Because the bridge is low to the water, itacts as a barrier to larger boats, although small boats (e.g., row boats, canoes, etc.) can still accessthe river adjacent to the site by going beneath the bridge. According to the Fisheries SectionProgram Manager, the Delaware Fish and Wildlife Department keeps no records on the numberof people using the Christina River near the Koppers site (5).
Two water companies, the Artesian Water Company and the Wilmington Suburban WaterCompany, service most of the population in the area. The Artesian Water Company usesgroundwater as its water supply source and has production wells scattered throughout NewCastle County. The nearest wells are approximately 2-1/2 miles to the southeast of the site, neara subdivision. The Wilmington Suburban Water Company gets its water from surface sources: Stanton Water Treatment Plant, whose water comes from White Clay Creek west of the site nearDelaware Park Race Track; and Christina Treatment Plant, whose water is obtained fromSmalleys Dam southwest of the site (2).
In areas where public water is not available, private wells are used. Most residences andbusinesses along Old Airport Road use private wells as their source of potable water. Theseprivate wells, serving approximately 100 people, were identified during a site investigation at theDuPont Holly Run plant. These well users are approximately 0.75 miles southeast of the siteacross the Christina River on Old Airport Road.
The Delaware Department of Public Health maintains a database that can provide the followingDelaware public health information: infant mortality, birth defects, tumor registry, and mortality. However, in order to properly evaluate these public health data, we must first have morecomplete site characterization (i.e., specific types and quantities of contaminants).
We know of no current public health concerns of residents living near the Koppers site, although,when State and local officials were contacted in an effort to glean concerns we discovered onepast concern. In an article in the July 18, 1978 issue of the Wilmington News Journal, residentsclaimed odors from the site caused nausea, burning throats and noses, and watery eyes (2). Inaddition, a residential well survey conducted for the DuPont Holly Run and the Ciba Geigyplants indicated that some private well users on Old Airport Road did not drink water from theirwells because of concern about contamination from Ciba Geigy and DuPont Holly Run plantsgetting into their well water (2).