U.S. ENVIRONMENTAL PROTECTION AGENCY, REGION II Emergency and Remedial Response Division 290 Broadway, 18th Floor New York, New York 10007-1866

MEMORANDUM

TO: Joe Cosentino, OSC (ERRD/RAB)

FROM: Chloe Metz, Risk Assessor (ERRD/PSB/TST)

DATE: November 30, 2010

RE: E.C. Electroplating (Garfield Chromium Groundwater Contamination Site) – Determination of Significant Threat

Introduction

The purpose of this memo is to document the Environmental Protection Agency’s (EPA) determination of significant threat for the Garfield Groundwater Contamination Site (GGCS). This document is consistent with 40 CFR Section 300.425(c)(3) of the National Oil and Hazardous Substances Contingency Plan. The Garfield Groundwater Contamination Site (a.k.a, E.C. Electroplating, Garfield Chromium Groundwater Contamination Site) consists of an area of groundwater contamination located within a mixed commercial/residential area in the Town of Garfield, New Jersey. The current site
boundaries are Van Winkle Avenue to the north, Monroe Street to the south, Sherman Place to the east, and the Passaic River to the West. EPA performed extensive sampling in the area and determined removal actions were necessary at thirteen properties based on the exceedence of the site-specific Removal Action Level (RAL). An exceedence of the RAL suggests that actual or potential exposure to concentrations of contaminants in these basements presents an unacceptable risk to occupants. Additionally, there is the potential

for recontamination and new contamination due to continued infiltration of contaminated groundwater exacerbated by weather conditions (i.e., heavy rains that cause flooding). Therefore, actual and threatened releases of hazardous substances from this site present a significant threat to public health and welfare.

Development of the RAL

Data collected from February 2009 through September 2010 from homes in the E.C. Electroplating Area of Concern (AOC) consisted of wipe samples (dust) from basementfloors and/or walls, some sediment samples from sump pumps and/or walls/floors, and sump water when it was available. However, only the Removal Action Level (RAL) developed for direct contact with dust is discussed below since the majority of samples collected in Garfield were dust samples and this was the only medium used to determine removal eligibility.

In 2007, the National Toxicology Program completed a study that identified hexavalent chromium as an oral carcinogen (previously, it had been considered by EPA to be an inhalation carcinogen only). On September 28, 2009, William Sette, former Senior Science Advisor in the Office of Solid Waste and Emergency Response (OSWER) provided Region 2 with a memo supporting the use of the oral slope factor developed by the New Jersey Department of Environmental Protection as a Tier III toxicity value (Attachment 1). According to the memo, this toxicity value of 0.5 (mg/kg-day) -1 is consistent with the third tier of the toxicity hierarchy from the 2003 OSWER Directive (EPA, 2003), because it “is based on the most recent science, has been peer reviewed, is publicly available, and, in the opinion of EPA's ORD, is "clearly written, understandable, and well organized", i.e. transparent.”

The RAL incorporated the NJ slope factor (Attachment 3) into the spreadsheet dust model developed and peer-reviewed for the World Trade Center response (Attachment 4). The model is based on “Standard Operating Procedures (SOPs) for Residential Exposure Assessment” originally published by the Office of Pesticides in 1997and updated in 2001 (EPA, 1997a and EPA, 2001a), as well as a number of other sources, including theSuperfund guidance on dermal contact (EPA,1989), the procedures used to develop reentry guidelines for the Binghamton State Office Building (Kim and Hawley, 1985), procedures used by NJDEP for setting interior building surface clean-up goals (NJDEP, 1993), the building clean-up procedures presented by Michaud et al (1994) and an approach developed by the EPA Region 3 Superfund program that has been employed by the U.S. Army Corps of Engineers to develop risk-based clean-up goals for interior surfaces at the Claremont Polychemical Superfund site (Radian, 1999).

In the AOC, some basements are finished living spaces where residents may spend a considerable portion of their day. Other basements in the study area are unfinished, rough spaces that may only contain a washer/dryer and/or storage and may not be accessed every day for long periods of time. Therefore, the RAL was developed with both high and low usage exposure parameters. Using two RALs allowed for actions to be planned accordingly based on current usage of contaminated areas.

During a telephone conversation on June 3, 2009, with Gilberto Irizarry and Janine Dinan of the Office of Emergency Management, within OSWER, verbal approval to set the

Removal Action Level at the 10 -5 cancer risk level, as opposed to the customary 10 -4 cancer risk, was provided. The 10 -5 cancer risk level was appropriate due to a number of uncertainties associated with the toxicity of hexavalent chromium.

1)	 EPA’s Office of Pesticide Programs developed an oral slope factor of 0.791 (mg/kg-day) -1 for hexavalent chromium to support the risk assessment for theChromated Copper Arsenate (CCA). Since this value has not been peerreviewed, it does not qualify as a Tier III toxicity value and cannot be used to support a removal action. However, it suggests that hexavalent chromium is a more potent carcinogen than the NJ value used to develop the RAL.

2) The OPP assessment also identified hexavalent chromium as acting by mutagenic mode of action (MMOA). Therefore, children may be more susceptible to this chemical. Both the high and low usage scenarios assume that young children have some contact with the hexavalent chromium. The age dependent adjustment factors (ADAFs) prescribed in the 2005 Supplemental Guidance for Assessing Susceptibility from Early-Life Exposure to Carcinogens were not applied here because hexavalent chromium is not specifically identified as an MMOA chemical in the guidance. However, since the state of science seems to support that this chemical acts by mutagenic mode of action, setting the RAL at a 10 -5

cancer risk level has a similar effect of applying the ADAFS

.

Below are the assumptions used in developing high and low use RALS. The assumptions are a combination of standard default exposure assumptions for Superfund risk assessment (EPA, 1989) and recommendation from the 1997 Exposure Factors Handbook (Tables 15­ 56, 15-118, and 15-117).

USE RAL Assumptions
High 1 10 ug/m2 or 1.1 ug/wipe • Developed using WTC dust model

• Ingestion only (no dermal or inhalation)

• No dissipation of chemicals assumed due to possibility of recontamination

• Exposure time: 8 hrs for soft surfaces; 4 hrs for hard surfaces (6 hrs soft; 2 hrs hard – school age 7-18)

• Exposure duration: 350 days/yr for 30 years

• 10 -5 cancer risk

Low 870 ug/m2 or 8.7 ug/wipe • Developed using WTC dust model

• Ingestion only (no dermal or inhalation)

• No dissipation of chemicals assumed due to possibility of recontamination

• Exposure time: Adults and children 11-18 yrs old (150 minutes); children 1-10 yrs old (60 minutes)

• All time in the basement is spent on hard surfaces

• Exposure duration: Adults and children 1- 5 yrs old (5 days/wk); children 6-18 yrs old (2 days/wk)

• 10 -5 cancer risk

The exposure assumptions for the low-use RAL are described in more detail below. Based on Table 15-56 of the EFH, 44% of adults, ages 18-64, do laundry between 3 and 7 days a week. Therefore, the RAL assumes a reasonable estimate would be 5 days a week. For children, the RAL assumes that ages 1-5 would also be in the basement 5 days a week, but for a more limited time, since parents may only bring them sometimes. Children, ages 6-18, are assumed to be in school 5 days a week, so their exposure occurs only on the weekend, or 2 days a week.The EFH provides estimates (in number of minutes) of the time spent in both the laundry/utility room (Table 15-118) and the basement (Table 15-117). For adults, the 90th percentile for time in laundry/utility room is 150 minutes. For basement, the 90th percentile value is 410 minutes. Since the basement value probably includes finished basements, it would be biased high for the low use scenario. Therefore, the laundry/utility room estimate of 150 minutes for adults was used. The RAL assumes that young children (1-11) spend less than half the time that adults do – 1 hour. For children older than 11, the RAL assumes that they could spend the same amount of time as an adult (150 minutes) since they might take over laundry responsibilities at that age. The limited data on this age group from the EFH support this assumption.

Conclusions

The concentrations of hexavalent chromium used in this analysis represent a discreet moment in time. Because the groundwater in the AOC is heavily contaminated with hexavalent chromium (maximum concentration in excess of 36 ppm) and the soils at E.C.Electroplating are still acting as a source, there will be continued contamination and recontamination of basements. Concentrations are likely to fluctuate as the basements get wet and dry out again and people clean. There is also the possibility that low use basements become high use basements in the future and concentrations that may not pose

a risk now will in the future.

In April 2010, NJDHSS and ATSDR issued a health consultation which assessed the potential hexavalent chromium exposures to area residents based on previous sampling investigations conducted by EPA in residential/commercial properties. Both agencies concluded that there is evidence of a complete exposure pathway regarding ingestion of and dermal contact with surface dust containing hexavalent chromium. Both agencies also concluded that past, present and future exposures represent a public health hazard via the ingestion of hexavalent chromium dust in some basements. In September 2010, ATSDR issued a Public Health Advisory for the site, recommending that EPA take

immediate measures to dissociate residents and others from the basement area of the properties showing the highest chromium levels in surface dust to prevent exposures from continuing. The Advisory also recommended that EPA take short- and long-term measures to dissociate individuals (in both residential and commercial properties), who are located in the area of the contaminant plume, from hexavalent chromium exposures due to the infiltration of contaminated groundwater into the basements of these properties.

To date, thirteen properties have had both groundwater infiltration and concentrations of hexavalent chromium in excess of the RAL. These properties are eligible for remediation and those efforts are ongoing. There are two properties with finished basements in the plume that do not currently exceed the high use RAL. EPA plans to monitor these to ensure that the basements do not become wet in the future. Of the 709 properties in the study area, there are still roughly 130 for which EPA has no information. Therefore, there is the potential that EPA is not aware of the full extent of contamination. There is also the possibility that the 288 homes that were previously identified as having groundwaterinfiltration problems, some of which were sampled and found to be clean (roughly 240), could become contaminated in the future. As the hotspot of the plume moves downgradient, basements that are not currently contaminated may become so if they have groundwater infiltration issues.

References

EPA, 1989. Risk Assessment Guidance for Superfund. Volume I: Human Health Evaluation Manual (Part A). Interim Final. Office of Emergency and Remedial Response, Washington, D.C. December.

EPA, 1997a. Draft Standard Operating Procedures (SOPs) for Residential Exposure Assessment. Office of Pesticides Programs. December 19, 1997.

EPA, 1997b. Exposure Factors Handbook. EPA/600/P95/002

EPA, 2001a. Science Advisory Council for Exposure. Policy Number 12 on Recommended Revisions to the Standard Operating Procedures (SOPs) for Residential Exposure Assessments . Revised: February 22, 2001

EPA, 2003. United States Environmental Protection Agency, Office of Solid Waste and Emergency Response. Human Health Toxicity Value in Superfund Risk Assessments.

Directive No. 9285.7-53. http://www.epa.gov/oswer/riskassessment/pdf/hhmemo.pdf

Kim N.K. and J. Hawley. 1985. Re-Entry Guidelines: Binghamton State Office Building.

New York

Lioy JL, Freeman CG, Millette JR. 2002. Dust: A Metric for Use in Residential and Building Exposure Assessment and Source Characterization. Environ. Health Persp. 110:

969-983.

Michaud, J.M., S.L. Huntley, R.A. Sherer, M.N. Gray, and D.J. Paustenbach. 1994. PCB and dioxin re-entry criteria for building surfaces and air. Journal of Exposure Analysis and Environmental Epidemiology 4(2):197-227.

New Jersey Department of Environmental Protection (NJDEP). 1993. Technical Basis and Background for Cleanup Standards for Contaminated Sites. N.J.A.C. 7:26D (Draft).

Radian International. 1999. Development of risk-based wipe sample cleanup levels at the Claremont Polychemical Superfund site in Old Bethpage, New York. Prepared for: U.S. Army Corps of Engineers.Attachment 1- Memo from William SetteAttachment 2 - Region 2 Memo to OSWER Requesting Use of NJ Slope Factor as a Tier III Value

U.S. ENVIRONMENTAL PROTECTION AGENCY, REGION II Emergency and Remedial Response Division 290 Broadway New York, New York 10007-1866

TO: William Sette, Senior Science Advisor, Office of Solid Waste and Emergency Response

FROM: Chloe Metz, Risk Assessor, Emergency and Remedial Response Division, Region 2

DATE: August 17, 2009

RE: Classification of the Oral Slope Factor for Hexavalent Chromium (Cr VI) Developed by New Jersey as a Tier 3 Toxicity Value

As defined in OSWER directive 9285.7-53, a Tier 3 value, “Includes additional EPA and non-EPA sources of toxicity information. Priority should be given to those sources of information that are the most current, the basis for which is transparent and publicly available, and which have been peer reviewed.” Region 2 believes that the oral slope factor for Cr VI of 0.5 (mg/kg-day) -1 developed by Alan Stern of the New Jersey Department of Environmental Protection meets the above definition. The assessment is current (released in July, 2009) and was subject to an external peer review which is available online ( http://www.state.nj.us/dep/dsr/chromium/peer-review-comments.pdf ). Added support for the use of this

OSF as a Tier 3 value is the fact that EPA-NCEA reviewed the draft risk assessment and concluded that it

was, “C learly written, understandable, and well organized, and it was, for the most part, consistent with EPA’s risk assessment methodologies.”

The hierarchy directive goes on to say that, “Consultation with the STSC or headquarters program office is recommended regarding the use of the Tier 3 values for Superfund response decisions when the contaminant appears to be a risk driver for the site.” As such, Region 2 respectfully requests that OSWER provide written support for the use of the New Jersey OSF for Cr VI to determine action levels for the Garfield site where Cr VI is the only contaminant

of concern.

References New Jersey Department of Environmental Protection (April, 2009). Derivation of Ingestion-Based Soil Remediation Criterion for Cr +6 Based on the NTP Chronic Bioassay Data for Sodium Dichromate Dihydrate. http://www.state.nj.us/dep/dsr/chromium/soil-cleanup-derivation.pdf

United States Environmental Protection Agency, Office of Solid Waste and Emergency Response (2003). Human Health Toxicity Value in Superfund Risk Assessments.

Directive No. 9285.7-53. http://www.epa.gov/oswer/riskassessment/pdf/hhmemo.pdf

cc: Michael Sivak

Helen Dawson

Stiven Foster

Janine Dinan

Dave CrawfordAttachment 3 – New Jersey Slope Factor

(under separate cover)Attachment 4 – Dust Wipe Model

(under separate cover)