FREELAND, LUZERNE COUNTY, PENNSYLVANIA
The tables in this section list contaminants of concern. However, their listing does not imply that a health threat exists. This public health assessment evaluates these contaminants in subsequent sections and determines whether exposure has occurred and, if so, if those exposures were at levels of public health significance. PADOH selected the contaminants based upon the following factors: on- and off-site concentrations, field and laboratory data quality, sample design, comparison of site-related concentrations with background concentrations, and comparison of site-related concentrations with ATSDR health comparison values for carcinogenic and noncarcinogenic endpoints. Sometimes contaminants are identified during the site investigation that are contaminants of concern, but are not necessarily associated with the site. Because the public health assessment's goal is to identify any health threat that may exist to the public, those contaminants are listed as contaminants of concern. Whenever possible, the source of that contamination is determined.
Other chemicals, such as arsenic and selenium, were present at the site, but were eliminated as contaminants of concern because they did not meet the criteria used for selecting contaminants of public health concern. Likewise, chemicals formed by processes conducted while the facility was active may also be present at the site; however, sampling data do not indicate any of those chemicals are contaminants of concern at this site.
In addition, EPA's Toxic Chemical Release Inventory database was accessed by PADOH through the National Library of Medicine's Toxicology Data Network and searched for estimated annual releases of toxic chemicals to the environment from industries within a 2-mile radius of the C&D Recycling site, to identify possible facilities that could contribute to groundwater and other media contamination near the site. No significant releases that would affect the quality of the groundwater or other media near the site were reported in the 1987, 1988, and 1989 databases.
AT&T Nassau Metals, under EPA supervision, conducted five rounds of on-site groundwater sampling during the RI from June 28, 1988, through June 22, 1989 (Figure 4). CompuChem Laboratories analyzed the groundwater samples for contaminants listed in the Target Compound List (TCL) Organics and Target Analyte List (TAL) Inorganics. Samples from round 3 were analyzed for lead, copper, and manganese only. Organic contaminants of concern were not detected at levels above comparison values (1). A summary of the analysis for groundwater follows:
Table 1. On-Site Contaminants of Concern (1)
@ - µg/L=micrograms per liter
a - Monitoring Wells
* - Estimated Value
MCLG - Maximum Contaminant Level Goal (MCLG)
RMEG - Reference Dose Media Evaluation Guide, calculated from EPA's reference dose
Soils and Air
AT&T Nassau Metals, under EPA supervision, obtained two rounds of soil samples (Figure 5). The first round was collected in June 1988. A total of 101 soil samples were collected from 0-6 inches of overburden. The second round of samples was collected in July 1989. A total of 64 samples were collected from 0-36 inches of soil by hand-augering. CompuChem Laboratories analyzed all soil samples (1).
Recon Systems, Inc. conducted the first of two air quality sampling rounds at the site on November 27, 1987 (Figure 6). The sampling was carried out during construction activities associated with site securing and erosion controls. Those construction activities were believed to represent a "worst-case" scenario for generating particles in the air. Three sampling units were set up on the site, and air was sampled over an eight-hour period. The second air sampling round was conducted at the site to determine if there were significant amounts of lead entrained in the airborne dust particles. Four samples were obtained in July 1988 and submitted to Recon Systems, Inc. for lead and copper analysis (1).
Table 2. On-Site Contaminants of Concern (1)
@ - mg/Kg=milligrams per kilogram
NT - Not Tested
NA - Not Available
* - Maximum Concentration
** - Levels above this range may to result in increases in blood lead levels in children if exposure occurs.
During the course of the RI, the following off-site environmental media were identified and sampled.
Groundwater and Surface Water
AT&T Nassau Metals conducted three rounds of groundwater sampling at five residences within a 1/2-mile radius of the site from June 1988 through June 1989. CompuChem Laboratories analyzed the samples for contaminants in the lists of TCL Organics and TAL Inorganics. Organic contaminants of concern were not detected at levels above comparison values. In addition, four rounds of off-site groundwater sampling from seventeen residences from June 1988 through June 1989 were collected (Figure 2). All residences were not sampled during each event. However, with the combined sampling, each well was sampled between three and five times. Seventeen wells had at least one reading of lead above the MCLG of µ0 g/L; each well also had at least one reading of lead below the EPA action level of 15 µg/L. The maximum lead concentration detected in a private well was 41 µg/L (1).
AT&T Nassau Metals, under EPA supervision, conducted surface water sampling in Mill Hopper Creek and in the pond water at the site in June 1988. A total of twelve surface water grab samples (two samples obtained at each of the four locations; the remaining four samples were filtered/unfiltered replicate and field blanks). Surface water samples were collected at the inflow of the pond, the center of the pond, the outflow of the pond, and approximately 300 feet downstream of the pond outflow (Figure 7). At each location, a sample set consisting of one filtered and one unfiltered sample was collected (1).
Table 3. Off-Site Contaminants of Concern (1)
@ - Unfiltered residential well water
a - µg/L=micrograms per liter
* - Maximum Concentration
a - Unfiltered Residential Well Water
NT - Not Tested
MCLG - Maximum Concentration Level Goal
RMEG - Reference Dose Media Evaluation Guide, calculated from EPA's reference dose
Soils and Sediment
AT&T Nassau Metals conducted three rounds of off-site soil sampling in June 1988, July 1989, and October 1989. Fifteen samples were collected from the top 6 inches of overburden in the first sampling round. Ten soil samples were collected from the surface and up to 3 feet in depth by hand-augering in the second sampling round. Twenty-one samples were collected in the third round, all within the top 6 inches of soil except for one sample collected at a depth of 1 foot. All samples were analyzed by CompuChem Laboratories. Four samples were collected in the pond, one from Mill Hopper Creek and two from the drainage swale west of the site (Figure 8) (1).
AT&T Nassau Metals, under EPA supervision, collected and analyzed 12 sediment samples in June 1988. Six samples were collected from Mill Hopper Creek and six samples were collected in the pond. In July 1989, an additional seven sediment samples were collected and analyzed by the same laboratory. Four samples were collected in the pond, one from Mill Hopper Creek and two from the drainage swale west of the site (Figure 9) (1).
Table 4. Off-Site Contaminants of Concern (1)
@ - mg/Kg=milligrams per kilogram
NT - Not Tested
NA - Not Applicable
* - Maximum Concentration
** - Levels above this range may result in increases in blood lead levels in children if exposure occurs.
All analytical data generated during the Remedial Investigation for the purpose of assessing the nature and extent of any environmental impact used EPA Contract Laboratory Program's (CLP) format. The required quality assurance/quality control (QA/QC) deliverables for CLP were supplied with each results package and reviewed by a qualified chemist to ensure the data were valid. EPA's Laboratory Data Validation Functional Guidelines for Evaluating Organic, Inorganic and Pesticides/PCBs Analyses was used to validate and qualify all analytical data. The analytical data were reviewed, and any quality control parameter that was out of specification was noted and the data were qualified accordingly. The data used in this public health assessment are both qualitative and quantitative, and estimated. The best data to use to evaluate site conditions are qualitative and quantitative data that have all critical QA/QC parameters within analytically acceptable control limits. As a result, the identification and concentration of organic compounds or inorganic constituents are known with a reasonable level of confidence.
Estimated data, those data that are qualitative but only semi-quantitative, have one or more QA/QC parameters outside of control limits, but not to the extent that the data are unusable. The identification of organic or inorganic constituents are known with a reasonable confidence level. However, a systematic error has occurred, which inhibits precise quantitation. Data presented in this document include estimated data so that possible worst-case conditions are not overlooked. Estimated data, when used, are indicated.
In preparing this public health assessment, PADOH relies on information provided in the referenced documents and believes that adequate quality assurance and quality control measures were followed regarding chain-of-custody, laboratory procedures, and data reporting. PADOH also believes that the qualifier code serves as a reasonable indication of the qualitative and quantitative reliability of the data presented in this public health assessment. The validity of the analyses and conclusions in this public health assessment depend on the reliability of the referenced information.
The site is fenced and not accessible to the public; however, in the event the site's security is breached, the furnace and the bales of wire may pose a physical hazard to trespassers.
To determine whether nearby residents are exposed to contaminants migrating from the site, PADOH and ATSDR evaluate the environmental and human components that lead to human exposure. This pathway analysis consists of five elements: a source of contamination, transport through an environmental medium, a point of exposure, a route of human exposure, and an exposed population. PADOH and ATSDR identify exposure pathways as completed, potential, or eliminated. A completed exposure pathway occurs when the five elements of an exposure pathway link the contaminant source to a receptor population. This exposure may be past, present, or likely to occur in the future. A potential pathway exists if one or more of the five elements are missing. Potential pathways indicate that exposure to a contaminant could have occurred in the past, could be occurring now, or could occur in the future. Eliminated pathways require that at least one of the five elements is missing and will never be present. The discussion that follows identifies the completed, potential, and eliminated pathways at this site. See Tables 5 and 6 for the completed and potential exposure pathways.
|EXPOSURE PATHWAY ELEMENTS|
|Surface Soil||Past||Site||Surface Soil||On-Site Soil||Ingestion||On-Site Workers|
|Air||Past||Site||Air||On-Site Air||Inhalation||On-Site Workers|
|EXPOSURE PATHWAY ELEMENTS|
|Site||Surface Water||Mill Hopper Creek, Pond & Wooded Area Around Site||Ingestion||Children & Other Residents Near the Site|
Creek, Pond & Wooded
|Ingestion||Children & Other Residents Near the Site|
Creek, Pond &
|Ingestion||Children & Other Residents Near the Site|
|Inhalation||Children & Other Residents Near the Site|
Past completed exposure pathways to lead and manganese are possible from contaminated on-site soils and air for on-site workers. Adults typically ingest 100 milligrams (mg) of soil per day. This information can be used to calculate an estimated dose people would receive. That dose can then be compared with health guidelines. While a completed exposure pathway for lead in air also exists, no data are known to be available to quantitatively estimate on-site worker and off-site residential exposure to lead and manganese during the operation of the facility.
Past, present, and future completed exposure pathways are possible for off-site residents through the ingestion of lead and manganese found in private well water. The source of the lead and manganese is not believed to be the C&D Recycling site. With the possible (but unlikely) exception of residential Well #10, groundwater flow from the site is not toward nearby residences. The source of lead and manganese in residential wells near the site is believed to be from naturally occurring elements in the soil. For instance, under acid conditions commonly found at coal mine spoils, the lead and manganese in soil may leach out of the soil and enter groundwater. Lead may also originate in residential plumbing.
The maximum concentration of lead and manganese detected during the Remedial Investigation in off-site residential wells was 41 µg/L and 644 µg/L, respectively. The typical child is considered to drink 1 liter of water per day. The typical adult is considered to drink 2 liters of water per day. When comparing a dose to the body through ingestion with a dose that researchers believe to be safe, PADOH and ATSDR use the maximum (worst-case) dose that the people may receive.
Past, present, and future potential exposure pathways to lead and manganese in off-site soil, surface water, sediment, and air theoretically exist for children and other residents; however, there is no information indicating that nearby residents were routinely exposed to elevated concentrations of site contaminants in these media. Young children typically ingest 200 mg of soil per day. With this information, PADOH and ATSDR can calculate worst-case conditions and an estimated dose that a child might receive.
That dose can then be compared with health guidelines for evaluation. While exposure to lead and manganese in off-site air also represents a potential completed exposure pathway, no data are known to be available to quantitatively estimate off-site residential exposure to those substances.
This section addresses health effects that may occur in persons exposed to site contaminants in site soils and non-site related elements found in private well water at levels above comparison values, and evaluates the relevancy of state health databases to provide information for the C&D Recycling site. To evaluate health effects, ATSDR developed Minimal Risk Levels (MRLs) for contaminants commonly found at hazardous waste sites. The MRL is an estimate of daily human exposure to a contaminant below which non-cancer, adverse health effects are unlikely to occur. MRLs are developed for routes of exposure, such as ingestion and inhalation and for the length of exposure, such as acute (less than 14 days), intermediate (15 to 364 days), and chronic (greater than 365 days). To further evaluate health effects, EPA developed Reference Doses (RfD). The RfD is an estimate of a daily exposure (mg/Kg/day) to the general public that is likely to be without appreciable risk of harmful effects during a lifetime exposure (chronic RfD) or exposure during a limited time interval (subchronic RfD). MRLs and RfDs are based on doses that have been shown to cause little or no adverse effects in humans or animals. Where human data are available, those data are preferred. More often than not, animal data are used because human data are not available. Because uncertainties exist when trying to relate doses derived from animal studies to human populations, safety factors ranging from 10 to 1,000 or more are used to calculate MRLs and RfDs.
EPA also developed Maximum Contaminant Levels (MCLs). Primary MCLs are federal drinking water standards promulgated under the Safe Drinking Water Act. MCLs are based on lifetime exposure to a contaminant from all sources (air, food, waste, etc.). Generally, an MCL for a toxic chemical represents the allowable lifetime exposure to the contaminant for a 70-Kg adult who is assumed to ingest 2 liters of water per day. In addition to health factors, an MCL is required by law to reflect the technological and economical feasibility of removing the contaminant from the water supply. The limit set must be feasible given the best available technology and treatment techniques. MCLs are applicable at the tap where the water will be provided directly to 25 or more people or will be supplied to 15 or more service connections, but, in addition, are relevant and appropriate requirements against which to evaluate all groundwater quality. PADOH will give consideration to standards and criteria developed by other organizations to determine whether the groundwater in the vicinity of the site is acceptable to use as a potable water supply.
People near the site with contaminated wells have been exposed to lead in their drinking water. From a special investigation conducted by PADOH (discussed in detail in the Community Concerns Evaluation section of this public health assessment), it appears that this exposure is to naturally occurring lead and possibly to lead originating in residential plumbing. Lead affects primarily the peripheral and central nervous systems, the blood cells, and metabolism of vitamin D. Lead also causes reproductive toxicity and is classified by EPA as a possible human carcinogen. The most sensitive target of lead poisoning is the nervous system. In children, neurologic deficits have been documented at exposure levels once thought to cause no harmful effects (14).
Neurologic deficits, as well as other effects caused by lead poisoning, may be irreversible. Effects in children generally occur at lower blood levels than adults. The developing nervous system in children can be affected adversely at blood lead levels as low as 10 micrograms per deciliter (µg/dL) and perhaps lower. Lead inhibits several enzymes that are critical to the synthesis of heme; however, low-level lead poisoning in children rarely results in anemia. Lead also interferes with a hormonal form of vitamin D, which affects multiple processes in the body, including cell maturation and skeletal growth. Lead-induced chronic renal insufficiency may result in gout. Furthermore, maternal lead stores readily cross the placenta, placing the fetus at greatest risk (8).
Some persons with lead poisoning may not be overtly symptomatic. Because of the differences in individual susceptibility, symptoms of lead intoxication and their onset may vary. With increasing exposure, the severity of symptoms can be expected to increase. In the early stages of symptomatic lead intoxication or mild toxicity, blood lead levels generally range from 35 to 50 µg/dL in children and 40 to 60 µg/dL in adults. Mild toxicity may result in muscle pain and irritability. Moderate toxicity may result in bone pain, general fatigue, difficulty concentrating, headache, diffuse abdominal pain and weight loss. Severe lead toxicity may result in encephalopathy, which may lead to seizures. A purplish line on the gums, known as a lead line, is rarely seen today, but if present, usually indicates severe and prolonged lead poisoning.
A blood lead level is the most useful screening and diagnostic test for lead poisoning (9). Current blood lead data for nearby sensitive populations and for other persons known to be exposed to lead in drinking water are not available at this time. Therefore, human exposure to lead and the corresponding public health implications associated with elevated blood lead cannot be addressed at this time. On June 7, 1991, EPA promulgated a Maximum Contaminant Level Goal (MCLG) of zero for lead. The purpose is to establish maximum human health protection by reducing the lead levels at consumers' taps as close to the MCLG as feasible. The MCL of 50 µg/L was in effect until December 7, 1992. Currently, there is no MCL for lead, but an action level of 15 µg/L has been established. Based on the maximum possible levels of exposure, long term exposure to lead in drinking water may adversely affect the health of some residents, with children being at highest risk.
Manganese is a naturally occurring element that exists in the environment. There is no direct evidence that manganese is beneficial or essential in humans; however, ingestion of manganese compounds is required in animals. While manganese may be essential at low intake levels, oral or inhalation exposure to high levels can cause adverse health effects. The most sensitive target organ of manganese is the central and peripheral nervous system. Ingestion of elevated levels of manganese in drinking water has been shown to cause neurological deficits in animals and may adversely affect humans. Manganese in drinking water may cause neurological effects in humans. While infants, children, and the elderly may be somewhat more susceptible to the neurotoxic effects of manganese than the general population, as indicated in Table 3, the maximum concentration of manganese in off-site groundwater was 644.0 µg/L. That level would not be expected to cause adverse health effects even in the aforementioned sensitive populations living near the site (15).
Inhaled manganese can also cause neurotoxicity. However, comprehensive off-site air sampling information is not available for manganese; therefore, potential human exposure via inhalation and the corresponding public health implication cannot be addressed at this time (15).
PADOH has evaluated health outcome data as follows: resident live births, infant deaths, and fetal deaths were reviewed for Foster Township for the 11-year period 1980-1990. Limitations of these data evaluation include under reporting because of information processing (miscoding), failure to report the miscarriage, and the inability to statistically compare a very small population out of a much larger population. The information will indicate if a very high trend in adverse pregnancy outcomes exists that warrants further investigation.
There were 341 resident live births reported in this period with no infant deaths (10). The infant death rate for Pennsylvania for 1980-1990 was 10.8 infant deaths per 1,000 births. Applying the state rate to the number of births in Foster Township, three or four infant deaths would have been expected. There was only one fetal death reported in Foster Township in the period 1980-1990 (fetal deaths are not yet available for 1990). The fetal death occurred in 1988. The mother's place of residence is near Freeland Borough and not in proximity to the site. Nonetheless, the fetal death rate for Foster Township is approximately 3 per 1,000 deliveries compared to 19 for the state over the same period.
Available infant and fetal mortality data indicate that there were no infant or fetal deaths in the 1980s in the vicinity of the site. However, three residents reported having miscarriages or stillbirths in the community close to the site. The information on those fetal deaths was not captured on the database because of either miscoding of the place of residence, the miscarriage occurred at less than 16 weeks gestation, or the adverse pregnancy outcome was not reported by the physician.
Fetal deaths under 16 weeks are not reportable; however, according to a recent study of the estimated number of total pregnancies for the United States, prepared by the National Center for Health Statistics (NCHS), the distribution of live births, fetal deaths, and induced abortions was found to be as follows:
Table 7. U.S. Estimated Total Pregnancies 1981 (11)
These estimates of pregnancies were based on data compiled by the Division of Vital Statistics, NCHS, and were prepared by summing the three outcomes: live birth, induced abortion, and fetal death. Live births are those tabulated by the Natality Statistics Branch, Division of Vital Statistics, from the birth registration system. Fetal death estimates were based on unpublished data from the National Survey of Family Growth, Division of Vital Statistics, conducted in 1982 by NCHS. These estimates were based on interviews with a national sample of about 8,000 women of child-bearing age and refer to their pregnancies of the previous five years. The estimates are undercounts of the actual number of fetal deaths to the extent that some fetal losses are not detected (11). The preceding data indicate that one of eight pregnancies would be expected to involve a fetal death. However, no data exist concerning the frequency of spontaneous abortions in early pregnancy.
The Foster Township pregnancy outcome cannot be compared to this national survey since the data collection was unique. The comparison of Foster Township's infant and fetal death rate to the state is more acceptable. That comparison was made; it indicated that Foster Township had a lower infant death rate and fetal death rate than the state for the period 1980-1989. The information on adverse pregnancy outcomes provided by the people living near the site was incorporated and the data were reevaluated. Again, no increased rate was seen for the community. Evaluation of a smaller community than Foster Township (such as that located near the site) is not possible with the databases available at this time.
In addition to the preceding evaluation, erythroprotoporphyrin (EP) commonly assayed as zinc protoporphyrin (ZPP), a method of screening for lead poisoning, and blood lead data were obtained by a private organization known as the Northeastern Pennsylvania Vector Control Association (NPVCA). Blood was drawn from 62 children residing in Foster Township on October 29, 1984. Seven children lived near the C&D site; the remaining children resided in more distant areas of Foster Township. All 62 children were sampled for EP; however, only 19 of the 62 children had their blood analyzed for lead.
When statistical tests were conducted on the blood lead data by an EPA Toxicologist, the seven children living near the site were found to have statistically significant blood lead levels compared to 55 children residing a greater distance from the site (12). A misinterpretation of the analysis appears to have been made. The 43 children who actually were not tested for blood lead were interpreted as non-detect for lead. PADOH believes that the children were, indeed, not tested for blood lead. Therefore, there have been seven children tested for lead near the site, and 12 children tested that were some distance from the site. This provides an entirely different data set. It is not possible from the available data to determine each blood lead value for all the children living near or distant from the site. However, the January 11, 1991, letter from an EPA Toxicologist to the Remedial Program Manager for the C&D Recycling site indicates two of the seven children near the site had blood levels that exceeded the Centers for Disease Control and Prevention's (CDC) and EPA's Region III blood lead criteria of 10 µg/dL (16). One child had a blood lead level of 16 µg/dL and another child had a blood lead level of 25 µg/dL (12). That information along with a statement from ATSDR's Region III Regional Representative which stated that only 19 children were tested for lead enabled PADOH to draw the following conclusions:
- Two out of seven (28.6%) children near the site had blood lead values above the 10 µg/dL level. Four out of twelve (33.3%) children more distant from the site had blood levels above 10 µg/dL.
- Five out of seven children near the site had blood levels in the 5-10 µg/dL range, and 8 out of 12 children more distant from the site had blood levels in the 5 to 10 µg/dL range (43 children were not tested).
Therefore, the distribution of the 19 known blood lead values provide no discernible difference in blood lead values near and distant from the site.
Table 8 shows the array of blood lead values for the 19 children.
|BLOOD LEAD VALUE
*Exceeds EPA Region III and the Centers for Disease Control and Prevention's blood lead criteria of 10 µg/dL (16).
The data contained birth dates for 14 of the 19 children. Their ages ranged from approximately 20 months to 67 months. There is no apparent correlation, based on the limited available information, between the age of children and blood lead levels. The data also fail to establish any clear relationship in blood lead values and distance from the site if, indeed, 43 children were not tested for blood lead levels.
Also, until recently, the test of choice for screening asymptomatic children and other populations at risk was EP. Using an EP or ZPP assay to screen children for lead poisoning is not as useful as once thought. The major disadvantage of using EP (ZPP) testing as a method for lead screening is that it is not as sensitive at the lower levels of lead poisoning. Findings from the second National Health and Nutrition Examination Survey (NHANES II) shows that a significant number of children with lead toxicity would be missed by reliance on EP (ZPP) testing alone as a screening tool. Therefore, the best screening and diagnostic test for lead poisoning is a blood lead level.
Due to the limitations of the data discussed in this section, additional blood lead analyses are necessary to determine the current public health significance of exposure to lead for residents near the C&D Recycling site.
Community concerns and responses to those concerns expressed during the second public comment period are presented in the Attachment at the end of this public health assessment.
PADOH has addressed the community concerns about health expressed during the investigation of this site as follows:
- Has lead migrated from the C&D Recycling site through groundwater and contaminated nearby residential wells?
Residences in the immediate vicinity of the site obtain water from the Mauch Chunk Formation, which also underlies the site. The quality of water obtained from the Mauch Chunk Formation is generally good. However, quality problems have been reported that include low pH, excessive concentrations of iron and manganese, and the presence of hydrogen sulfide in areas proximal to mining operations (1). Table 9 compares regional averages for lead concentrations in the Mauch Chunk Formation with lead concentrations found in residential and monitoring wells tested during the Remedial Investigation.
Number of Samples
17 Residential Wellsa 7.17 65 5 Residential Wellsb 7.57 16 On-Site Monitoring Wellsc 9.07 37 Mauch Chunk Formationd 7.00 17
a - Includes results from samples collected by U.S. EPA and HART.
b - Results from HART sampling only.
c - Includes results from open boreholes and construction wells.
d - Results from Taylor, 1984.
Note: For the purpose of averaging, the detection limit value was used for results reported as not detected.
As indicated in Table 9, the levels of lead in groundwater slightly exceed background concentrations in the Mauch Chunk Formation, but are below EPA's Action Level of 15 µg/L. There is no identifiable groundwater plume associated with this site and no indication that lead is migrating from the site and contaminating nearby residential wells. While the average concentration of lead in groundwater corresponds closely to the concentration of lead in the Mauch Chunk Formation, a few private wells near the site had levels of lead that necessitated a field investigation to attempt to determine the source of the lead and to further confirm the lead present in residential well water was not site related.
Geological information gathered during the field investigation and from published reports on area coal mining provide evidence that groundwater flow is southward at the southern part of the site and northward from the northern property line. Evidence also exists that a groundwater divide crosses the site approximately parallel to the northern property line. Therefore, as clarified earlier in the Site Visit section, residential wells east and west of the site should not be in a position to intercept groundwater migrating from the site. Residents north of the site are located approximately 1/4 mile from the site. Because of the groundwater flow regime, the groundwater quality at those residences should not be affected by groundwater at the site. Lead in groundwater in this area can reasonably be attributed to the dissolution of naturally occurring lead from the Mauch Chunk Formation by acidic surface and groundwater associated with coal mine spoil. There is no known residence immediately south of the site, and, as stated in the Site Visit section, there is no definable groundwater plume associated with the site.
The evaluation of residential Well #1 posed a unique dilemma. The property is geologically upgradient of the site, and groundwater in the well showed elevated levels of lead (up to 41 µg/L). The elevated level is several times higher than the neighboring residential Well #2, which is located approximately 200 feet to the west, and significantly higher than the average levels of lead in newly drilled residential wells or in the Mauch Chunk Formation. A pH as low as 4.2 and other low pHs have also been consistently detected in residential Well #1. On the morning of October 9, 1991, the field investigation team, identified in the Site Visit section, discovered a possible cause for elevated lead in residential Well #1. An elongated pile of coal mine spoil (probably an old railroad bed) crosses the property topographically and is geologically upgradient of residential Well #1. The spoil passes through the property where residential Well #2 is located, but is downgradient of Well #2. The spoil probably causes the acidic recharge waters identified upgradient of residential Well #1, and, in turn, is the likely cause of the elevated lead concentrations detected in Well #1. Residential Well #2 probably experiences little, if any, effect from the coal waste as indicated by relatively lower lead concentrations. The presence of the coal mine waste was not known or not mentioned in any report associated with the site.
- Could the levels of lead present in private wells near the site produce adverse pregnancy
The highest lead level of five residents' wells within a 1/2-mile radius of the site was 41 µg/L. That level and the other lower levels of lead detected in private wells are higher than the present MCLG of 0 µg/L for public water supplies. The levels are below the former MCL of 50 µg/L that was the standard for potable water at the time of the remedial investigation. Because the current health goal is to prevent exposure to lead, the levels detected in the private wells are of public health concern.
As stated in the Toxicological Evaluation section, exposure to high levels of lead is especially dangerous to unborn children because they can be harmed during the development of the fetus. Pregnant women exposed to lead can pass lead to unborn children, causing premature birth, low birth weight, and miscarriages (9).
- Is there an elevated level of adverse pregnancy outcome in the area of the C&D
As stated in the Health Outcome Data Evaluation section, the evaluation of pregnancy outcome (infant and fetal mortality) indicated no elevation in adverse outcome in comparison to the state data. Pennsylvania does not require the reporting of spontaneous abortions under 16 weeks. People living near the site informed PADOH and ATSDR that at least one stillbirth and possibly other miscarriages were not captured in the database for analyses. After reevaluating the numbers involved to include those adverse pregnancy outcomes, the rate of adverse pregnancy outcomes for Foster Township is still lower than the state's. Analysis of the smaller community around the site is not possible at this time because databases are not established that would allow that.
There is a section on the birth certificate under the heading Confidential Information for Medical and Health Use Only that attempts to obtain a pregnancy history. One question asks about "other terminations" before 16 weeks and after 16 weeks and the date (month and year) of last other termination. However, those data are not appropriate for answering public health questions addressing miscarriages or other adverse pregnancy outcome for the following reasons:
- A pregnancy involving a live birth outcome would be necessary to report this information.
- Previous terminations of pregnancy may have occurred in other geographic areas.
- The completeness of data collection varies in geographic areas.
- Much of the data from this section of the certificate are not routinely summarized and disseminated because some of the pregnancy outcome questions are subjective.
- Is the alternative for on-site disposal of stabilized materials effective over a long period
The selected remedy of removal of stabilized contaminated materials and off-site disposal is protective of public health over the long term. However, during the actual removal of materials, a very slight risk of exposure to contaminants exists, especially if conditions are windy and dry (17). The potentially responsible parties have submitted a proposal for stabilization and on-site disposal to EPA. ATSDR has requested to review the document because the community has asked the agency to do so. However, EPA is responsible for the final decision on any remedial action.
Although the proposal for on-site disposal has not been reviewed by ATSDR yet, questions that should be evaluated include (but may not be limited to):
Have future land use practices on and near the site been considered?
Have the effects of acid rain been considered?
Has a plan for long-term monitoring of the cell and environmental media in the area been established?
Is the design based on sound engineering principles?
Is a cell-failure contingency plan developed?
ATSDR's evaluation will be submitted to EPA, although the comments may not be incorporated into their decision because of time constraints and because other reviewers will address similar issues.
One way to ensure the safety of the community over an indefinite period of time is to implement deed and land use restrictions. For instance, zoning of the property could ensure restriction of future use of the site. Deeds to property south of the site could impose restrictions on well development or monitoring of private wells could be instituted. Since contaminant stabilization and on-site disposal of those materials is a relatively new process, such institutional controls may be the only way to ensure public health safety until such a time that monitoring indicates no further need to do so.