Superfund Program Proposed Plan U.S. Radium Superfund Site August 2006 U.S. Environmental Protection Agency, Region II EPA ANNOUNCES PROPOSED PLAN This Proposed Plan presents the preferred No Action remedy for the ground water at the U.S. Radium Corp. Superfund Site located in Essex County, New Jersey (Site) and presents the rationale for that preference. This document is issued by the U.S. Environmental Protection Agency (EPA), the lead agency for Site activities. The New Jersey Department of Environmental Protection (NJDEP) is the support agency. The No Action remedy described herein is the preferred remedy for Operable Unit 3 (OU3) of the Site, which addresses ground water at the Site. Operable Units 1 and 2 addressed radiologically contaminated soil and building materials at the Site. EPA, in consultation with NJDEP, will select a final remedy for OU3 after reviewing and considering all information submitted during the 30-day public comment period. EPA, in consultation with NJDEP, may modify the preferred remedy based on new information or public comments. EPA is issuing this Proposed Plan as part of its public participation responsibilities under Section 117(a) of the Comprehensive Environmental Response, Compensation and Liability Act of 1980, as amended (CERCLA), and Section 300.430(f) of the National Oil and Hazardous Substances Pollution Contingency Plan (NCP). This Proposed Plan summarizes information that can be found in greater detail in the Remedial Investigation (RI) report and other documents contained in the Administrative Record file for OU3 of this Site. EPA and NJDEP encourage the public to review these documents to gain a more comprehensive understanding of the Site and Superfund activities that have been conducted at the Site. SITE HISTORY The former U.S. Radium Corporation facility, which covers 2 acres in the City of Orange, is a former radium- processing plant where extraction, production, application, and distribution took place from about 1915 through 1926. Approximately VT. ton of ore per day was processed and disposed of on and off the property. The original facility Dates to remember: MARK YOUR CALENDAR PUBLIC COMMENT PERIOD: August 10 to September 8, 2006 U.S. EPA will accept written comments on the Proposed Plan during the public comment period. PUBLIC MEETING: August 22, 2006 U.S. EPA will hold a public meeting to explain the Proposed Plan and the preferred No Action remedy. Oral and written comments will also be accepted at the meeting. The meeting will be held at the Orange City Hall Council Chambers located at 29 North Day Street in Orange, New Jersey at 7:00 p.m. For more information, see the Administrative Record at the following locations: U.S. EPA Records Center Region II 290 Broadway, 18th Floor. New York, New York 10007-1866 (212)637-3261 Hours: Monday-Friday, 9 am to 5 pm Orange Public Library 348 Main Street Orange, New Jersey (973)673-0153 West Orange Public Library 46 Mount Pleasant Avenue buildings were removed in 1999 as part of the remedial action. In addition, radium-contaminated soil and debris were identified at approximately 250 noncontiguous properties in the vicinity of the former plant and at various satellite locations throughout the municipalities of Orange, West Orange, and South Orange. At this time, investigations to identify additional contaminated properties are complete. The noncontiguous vicinity and satellite properties are occupied by residences, light industries, offices, grocery stores, and apartment buildings. The main portion of the Site is located in a densely populated, urban residential neighborhood. All area residents and businesses are supplied with municipal water. A Proposed Plan for the first operable unit (OU1) was released to the public on April 28, 1993, along with an OU1 Remedial Investigation and Feasibility Study (RI/FS) Report. OU1 consisted of mostly residential properties. On September 21, 1993, a Record of Decision (ROD) was ------- signed for the OU1 properties, selecting a remedy of excavation of radium-contaminated material from affected properties, restoration of the excavated areas, and off-site disposal of the radium- contaminated material. A Proposed Plan for the second operable unit (OU2) of the Site was released to the public on May 23, 1995, along with an OU2 RI/FS Report. OU2 consisted of the remainder of the Site; namely, the former U.S. Radium facility at High and Alden Streets, plus four other commercial properties used by U.S. Radium. On August 29, 1995, a ROD was signed for the OU2 properties, selecting essentially the same remedy as that for the OU1 properties: excavation of radium-contaminated material, restoration of the excavated areas, and off-site disposal of the radium-contaminated material. The OU1 and OU2 remedial actions are now essentially complete. Overall, approximately 650 properties were investigated during the remedial design. Of these properties, approximately 250 were identified as requiring remediation under the selected actions. Previous ground water sampling events indicated the presence of dissolved radionuclides, specifically radium, thorium, and uranium in the ground water underlying the former U.S. Radium facility, but the results were not conclusive. Since the time of the OU1 and OU2 investigations, most of the contaminated source material has been removed from the former U.S. Radium facility area. SITE CHARACTERISTICS The City of Orange is located in the lower valley portion of the Passaic River Drainage Basin. Ground water in the Site's vicinity occurs in the unconsolidated glacial sediments (shallow, overburden aquifer) and in Passaic Formation bedrock (deeper aquifer). Ground water flow in the overburden is generally east-southeast. A slight upward flow of ground water is present at the Site, particularly in wells immediately down-gradient of the former U.S. Radium facility. The upward gradient between the deeper ground water and the shallow overburden ground water limits the downward movement of ground water. The overburden aquifer currently is not used for domestic or industrial water supply. While it is not expected that it will be used in the future as a source of potable water, it is classified by NJDEP as Class IIA, which means that it can be with appropriate treatment. All area residents are supplied with municipal water provided through United Water of Orange. From the early 1990s to 2005, the soil remedial action resulted in the removal of up to 15 feet of radiologically contaminated material at the former U.S. Radium facility. Therefore, the primary source of radiological contaminants beneath and immediately down-gradient of the Site has been removed. The ground water investigation was conducted in two phases (see Figure 1). First, a site-wide analysis was conducted which included wells located both at the former facility area and at various locations in the vicinity of the former facility where radiological contamination was found at residential and/or commercial properties. The second phase of investigation focused on a small area at which elevated concentrations of uranium in ground water were detected. It should be noted that the investigation evaluated the ground water for the presence of site-related radiological contamination only; other organic and inorganic contaminants may be present in the ground water, but were not part of this RI. Site-Wide Ground Water Investigation A comprehensive ground water investigation was planned in order to determine if site-related contamination had affected ground water at the former facility area or near any of the other approximately 250 properties from which radiological contamination was removed. As such, ground water samples were collected from 13 wells in 2003, and again in 2004 to verify the results. Two of these wells were located on the former facility area, and the rest were placed throughout Orange and West Orange. As part of this investigation, water from one of the supply wells located at Gist Place, which are used for the City of Orange residents, was tested for the presence of radiological contamination. Results of the sampling showed no evidence of a site-wide ground water radiological contamination problem. In general, concentrations of the site-related radionuclides were comparable to naturally occurring concentrations. In particular, the water supply well did not exhibit any elevated concentrations of site-related contaminants. One of EPA's shallow monitoring wells (Well P-2) did, however, have elevated concentrations of uranium. The maximum concentration of uranium detected in this well was approximately 127 micrograms per liter (ug/1), where ------- as the Federal Primary Drinking Water Standard for uranium is 30 ug/1. This well is located at the southeast corner of the former facility property. None of the other site-related contaminants, including the primary contaminant of concern at the Site, radium, were elevated at this well, nor were uranium concentrations elevated in a well co-located with this well but drawing water from a deeper interval. In addition, a well located approximately 800 feet down-gradient of this well did not exhibit elevated concentrations of uranium. Therefore, it was determined that additional investigation would be required to bound this apparently limited area of contamination near Well P-2. Since it was determined that a site-wide ground water problem does not exist, the remainder of the investigation focused on the Well P-2 area. Well P-2 Area Investigation The Well P-2 Area ground water investigation was completed over several phases. ------- In June 2004, soil and ground water samples were obtained from 7 locations in the vicinity of Well P-2. The samples were collected from several discrete intervals below the ground surface, and the soil data was used to determine if a source of uranium remained there. In order to further define the area of contamination, ground water from 9 additional locations was sampled in spring 2005. Ground water was collected at five-foot intervals to a maximum depth of approximately 50 feet below the ground surface, which is where the bedrock starts. These portions of the investigation revealed an area of uranium contamination in the ground water limited in both areal and vertical extent. The results showed that the depth of contamination is limited to the shallow portion of the aquifer just below the water table and extends laterally for approximately 100 feet, to a location approximately 45 feet down-gradient of the former facility area. Samples collected further up-gradient and down-gradient of these locations, and at greater depths, contained significantly lower concentrations of uranium, below drinking water standards. Soil sample results did not identify a clear source of uranium in ground water. Based on the results obtained above, 10 additional monitoring wells were installed in 2006. These wells were installed at locations from which data can be obtained within, below, and just outside of the area of contamination over a long-term period. Ground water from these new wells, along with 10 previously sampled wells, has since been analyzed twice, in April and May 2006, for the presence of radiological contamination. The results confirm the earlier findings that the contamination is limited in both areal and vertical extent. The results of data from these wells were also used to determine that ground water flows at a slightly upward gradient, which further limits the migration of contamination to the deeper bedrock aquifer. Since no source of contamination in the soil was located during the 2004 and 2005 sampling efforts, additional soil from USGS Orange. Wew Jersey 7 5 minute Qudc'fang/e, dated '955 COM Figure 1 Site Location Map U.S. Radium Superfund Site Orange, New Jersey ------- samples were obtained in spring 2006. Soil samples were collected at approximately 50 locations on the former facility property, with a large portion concentrated near well P-2. Once again, samples were obtained from discrete intervals down to bedrock in some locations. An iterative approach was used, and additional locations were sampled as results were obtained. Ground water was also sampled at some locations to gain additional information about the potential source area and flow patterns. The soil investigation revealed that the bulk of the uranium remaining in the soil was located over a relatively small area of approximately 50 feet by 50 feet just up-gradient of and encompassing Well P-2. The bulk of the elevated uranium concentrations was also limited to a depth of approximately 8 to 10 feet below the ground surface; samples obtained from intervals deeper than this generally had significantly lower concentrations of uranium These results are in line with the results EPA obtained from Well P-2, which draws water from a depth of 7 to 17 feet below the ground surface; water from Well P-2D, which draws water from 33.5 to 43.5 feet below the ground surface does not exhibit elevated concentrations of uranium. As a result of these findings, additional soil removal was initiated in July 2006. Approximately 200 to 400 cubic yards of soil with slightly elevated concentrations of uranium are being removed from the Site, and will be disposed of at an appropriate off-site facility. This will effectively remove the majority of the known source of the ground water contamination. It should be noted that the earlier excavation activities conducted at the former facility area focused on the presence of radium, which is the primary contaminant of concern at the Site. A field screening process was used to determine if all of the radium-contaminated soil had been removed, but this process could not detect the presence of uranium. As a result, this small area of uranium contamination in soil was not addressed previously. This is not, however, indicative of a site-wide problem, as evidenced by the ground water sampling results and, primarily, by the operational procedures that were utilized by the former U. S. Radium Corporation, as described below. Historical Analysis The first question that arose from the above findings was how the uranium got into the soil. In order to answer this question, the operational procedures used by the U.S. Radium Corporation were reviewed. The corporation would obtain ore containing naturally high levels of radium. In order to extract the radium, the uranium that was also present in the ore had to be removed. Thus, acid was used to leach the uranium out of the ore and, presumably, the uranium-rich acid waste was then disposed of outside of the treatment building, either directly onto the ground or into floor drains. Plans exist which show the layout of the buildings that existed when the U.S. Radium Corporation was operating and the uses of those buildings. The area of contamination is outside of the footprint of any of the buildings that existed and on a corner of the former facility property. Therefore, the presumed operational procedures employed by the corporation support the findings of the investigation. Geochemical Analysis Once it was understood how the uranium got into the ground water, the next question became why is it not moving significantly off-site. The area of contamination has essentially remained stationary since it was first placed there approximately 90 years ago. In order to understand this, a geochemical analysis was performed. Several possible explanations for the low-mobility of the uranium were explored, including adsorption and coprecipitation. Adsorption is the process whereby an ion in solution adheres to the surface of a soil or sediment grain in contact with it. These adsorbed substances will then not move with the ground water flow. Coprecipitation occurs when an element, such as uranium, is incorporated into a solid mineral, thus affecting the mobility of the substance. Some major factors that may affect the mobility of uranium in ground water include the pH of the water, the oxidation- reduction potential of the water (Eh), carbonate and phosphate levels in the water, organic carbon levels, and the nature of the soil and/or sediment in the aquifer. In this case, it was found that neither adsorption nor precipitation of pure uranium were the dominant processes affecting the mobility of the uranium. Rather, pure uranium is being reduced to another form which then coprecipitates easily with another mineral, calcite. Organic carbon levels in the aquifer increase just down-gradient of Well P-2, and thus the uranium is removed from the ground water as it flows away from the Site. While the above explanation is greatly simplified, more detail can be found in the Remedial Investigation report. ------- The results of the geochemical analysis correspond with the uranium concentrations that have been actually detected in the ground water. The analysis provides an adequate explanation of why the uranium contamination was found over such a limited area, and also provides assurance that the area of contamination will not likely expand in the future. SCOPE AND ROLE OF THE ACTION The remediation of the Site has been addressed in three operable units. OU1 and OU2 were the subject of prior RODs and have been addressed. This action, referred to as OU3, is intended to be the final action for the Site. This Proposed Plan summarizes the rationale for the preferred No Action alternative to address ground water at the U. S. Radium Site. SUMMARY OF SITE RISKS As part of the RI for the ground water, two baseline human health risk assessments (BHHRA) were performed. A BHHRA is an analysis of the potential adverse human health effects caused by exposure to hazardous substances from a site in the absence of any actions or controls to mitigate that exposure under current and potential future land uses. The first BHHRA was based on the results of the site-wide investigation and excluded data from the P-2 Well. The second BHHRA was based on data obtained during the Well P-2 Area investigation. Site-Wide Risk Assessment As described in the box "What is Risk and How is it Calculated?", the site-wide BHHRA followed a four step process that includes: Hazard Identification, Dose Response, Exposure Assessment, and Risk Characterization. A brief description of the results of each of these steps is provided below. Hazard Identification: The BHHRA used data meeting all appropriate QA/QC requirements. The assessment identified a number of Contaminants of Potential Concern (COPCs) that were evaluated in the BHHRA. Based on this analysis, the primary COPCs evaluated included radium, radon, thorium, and uranium. Dose-Response: Toxicity data was obtained form EPA's consensus toxicity database, the Integrated Risk Information System, and other appropriate sources including the Health Effects Assessment Tables. Toxicity data included radionuclide-specific toxicity values for cancer and non-cancer health effects. Toxicity values for inhalation, dermal absorption, and ingestion of COPCs in ground water were selected based on the potential routes of exposure and available toxicity information. Exposure Assessment: The BHHRA focused on future health effects to both adult and child residents exposed to ground water from the overburden water bearing used being used as a tap water source in the future. Exposure routes included ingestion and dermal contact with the water, and inhalation of the COPCs while showering. The BHHRA evaluated exposures in the absence of institutional controls or remedial actions. Reasonable Maximum Exposure (RME) assumptions were used to be protective of human health and account for uncertainties in the risk assessment process. Risk Characterization: Data from the previous steps were combined to calculate cancer risks and non-cancer health hazards, which are expressed as a total Hazard index (HI). The site-wide BHHRA found that the potential future risks were within the upper bounds of the risk range for cancer of 10"6 to 10"4, and below an HI of 1 for non-cancer. The total RME cancer risk for adult and child residents exposed to the Site ground water was 3x10"4, where approximately 90% of this risk is associated with inhalation of radon in the air while showering from ground ------- WHAT IS RISK AND HOW IS IT CALCULATED? A Superfund human health risk assessment is an analysis of the potential adverse health effects caused by hazardous substances released from a site in the absence of any actions to control or mitigate these releases; it estimates the "baseline risk" in the absence of any remedial actions at the site under current and future land uses. To estimate this baseline risk at a Superfund site , a four-step process utilized for assessing site-related human health risk for reasonable maximum exposure (RME) scenarios. Hazard Identification: The hazard identification step identifies the contaminants of potential concern (COPC) in ground water for this specific site. Factors considered include: toxicity, frequency of occurrence, fate and transport of the contaminants in the environment, concentrations of the contaminants in specific media, mobility, persistence, and bioaccumulation. Exposure Assessment: In this step, the different exposure pathways through which people might be exposed to the contaminants identified in the previous step are evaluated. Examples of exposure pathways for a groundwater site include ingestion of groundwater and inhalation of volatiles while showering. Factors relating to the exposure assessment include but are not limited to the concentrations that people might be exposed to and the potential frequency and duration of exposure. Using these factors, a RME scenario, which portrays the highest level of human exposure that could reasonably be expected to occur is calculated. Toxicity Assessment: The toxicity step determines the types of adverse health effects associated with exposures to chemicals or radionuclides, and the relationship between the magnitude of exposure (dose) and severity of adverse effects (response). Potential health effects are chemical or radionuclide-specific and may include the risk of developing cancer over a lifetime or other non-cancer health effects such as changes in the normal functions of organs within the body (e.g., changes in the effectiveness of the immune system). Some chemicals are capable of causing both cancer and non-cancer health effects. Risk Characterization: This step summarizes and combines outputs of the exposure and toxicity assessments to provide a quantitative assessment of site risks. Exposures are evaluated based on the potential risk for developing cancer and the potential for non-cancer health hazards. The likelihood of an individual developing cancer is expressed as a probability. For example, a 10 4 cancer risk means a "one in ten thousand excess cancer risk"; or one additional cancer maybe seen in a population of 10,000 people as a result of exposure to site contaminants under the conditions explained in the exposure assessment. Current federal Superfund guidelines for acceptable exposures are an individual lifetime excess cancer risk in the range of 104 to 106 (corresponding to a one-in-ten- thousand to a one-in-a-million excess cancer risk). For non- cancer health effects, a "Hazard Index" (HI) is calculated. An HI represents the sum of the individual exposure levels compared to their corresponding Reference Doses (RfDs). The key concept for a non-cancer Hazard Index is that a "threshold level" (measured as an HI of 1) exists below which non-cancer water. The concentrations of radon present in the ground water are naturally occurring and not site-related. Well P-2 Area Risk Assessment The same four-step process was used for the Well P-2 Area risk assessment. It was based on the maximum detected concentration of each COPC in the focused Well P-2 Area. This risk assessment showed that, even at Well P-2, the potential future cancer risks were within the upper bounds of the risk range. The non-cancer hazard index slightly exceeded the threshold level of 1 for a potential future receptor, with a total HI of approximately 4 for the RME future resident, while the Central Tendency, or average, exposures resulted in an HI of approximately 2. The future residential scenario assumed the RME individual would be exposed to only this small geographic area and would obtain all of their drinking water from only this one locatioa EPA has taken actions through the removal program to remove the source in this area, which will further reduce the potential future non-cancer hazard identified above. EPA will continue to monitor the wells in and around this area to assure the remedy remains protective. Ecological Risks The need for an ecological risk assessment was evaluated during OU1 and OU2 of this Site. There are no exposure pathways for ecological receptors to ground water at this Site. Therefore, an ecological risk assessment was not performed as part of this investigation. EVALUATION AND SUMMARY OF THE PREFERRED NO ACTION ALTERNATIVE After careful consideration of the site-specific details and analysis of all data collected, EPA has determined that a No Action remedy, with monitoring, is the preferred remedial approach. EPA has determined that this remedial approach is protective of human health and the environment based on the following: • Currently, water is provided to the residents in the vicinity of the Site via the local water company. There is presently no elevated risk posed by the Site ground water since no potable wells are located within the contaminated area or considered threatened by the contaminated area. The supply well that provides water to area residents has been tested several times and does not contain elevated concentrations of site- related contaminants. Further, water from the supply ------- well is regulated by NJDEP and is tested on a regular basis. The supply wells are not threatened by site- related contamination for two primary reasons. First, the area of contamination is not moving significantly from where it is now. Second, even if it were to move, the supply wells draw water from the bedrock aquifer, which is significantly deeper than the affected water. Furthermore, the presence of an upward gradient within the bedrock zone creates a hydraulic barrier which limits the migration of contaminants from the shallow aquifer. • A geochemical analysis of the Site data provides a scientific basis for why the area of contamination is neither moving nor expanding significantly. The geochemical processes that are occurring at the Site will continue into the future. • Although non-cancer human health risks to potential future residents are slightly elevated, this would only occur if a potable well were installed in the Well P-2 area, which is considered highly unlikely. The extent of contamination is limited and does not intersect any current or potential future residential properties. Further, the depth of contamination is shallower than a potable well would likely be installed. Finally, all area residents are supplied with municipal water; there is no reason to install a potable well. • Concentrations of uranium in the area of contamination are expected to decrease with time, since the bulk of the source of the contamination in the soils is being removed. As part of the No Action remedy, a ground water monitoring program will be implemented. The monitoring will assure that the No Action remedy remains effective and protective of human health and the environment. The monitoring program may be modified on an on-going basis depending upon the sampling results obtained. Currently, EPA does not believe that additional wells will be required for the purpose of the sampling program. However, if the results of any sampling round indicate that additional wells are necessary, they will be installed. If all results clearly show that uranium concentrations in ground water decrease to levels below drinking water standards, then monitoring may be discontinued. Alternatively, additional action may be taken if monitoring shows that it is warranted. The present worth cost of the initial monitoring program, which is anticipated to include semi-annual testing of the 20 wells that were sampled in 2006 and last for five years, is estimated to be approximately $360,000. Because contamination is being left in place, a Five-Year Review will be required. Since the bulk of the source of the uranium contamination is being removed, EPA anticipates that the concentration of uranium in ground water will decrease and that drinking water standards will be met by the end of the first five years of monitoring. The preferred No Action remedy for the Site has been developed based on the findings contained in the Remedial Investigation Report for OU3, which includes the baseline Risk Assessment, a Focused Risk Assessment memorandum developed for the Well P-2 Area, and a soil investigation report prepared by EPA. As described herein, the remedy does include ground water monitoring to ensure that the public is not exposed to the small area of site- related ground water contamination at the Site. EPA believes the preferred remedial approach is protective of human health and the environment. COMMUNITY PARTICIPATION EPA and NJDEP provide information regarding the cleanup of the U.S. Radium Site to the public through public meetings, the Administrative Record file for the Site, and announcements published in the Star Ledger and the Orange Transcript. EPA and the State encourage the public to gain a more comprehensive understanding of the Site and the Superfund activities that have been conducted there. The dates for the public comment period, the date, location and time of the public meeting, and the locations of the Administrative Record files, are provided on the front page of the Proposed Plan. EPA Region 2 has designated a public liaison as a point-of-contact for community concerns and questions about the federal Superfund program in New York, New Jersey, Puerto Rico, and the U.S. Virgin Islands. To support this effort, the Agency has established a 24-hour, toll-free number that the public can call to request information, express their concerns, or register complaints about Superfund. ------- For further information on the U.S. Radium Site, please contact: Stephanie Vaughn Pat Seppi Remedial Project Manager Community Relations Coordinator (212)637-3914 (212)637-3679 U.S. EPA 290 Broadway, 19lh Floor. New York, New York 10007-1866 The public liaison for EPA's Region 2 office is: George H. Zachos Regional Public Liaison Toll-free (888) 283-7626 (732) 321-6621 U.S. EPA Region 2 2890 Woodbridge Avenues, MS-211 Edison, New Jersey08837 ------- |