explanation of significant difference to the remedial

EXPLANATION OF SIGINIFICANT DIFFERENCE TO THE REMEDIAL ACTION

BARBER ORCHARD SUPERFUND SITE WAYNESVILLE, HAYWOOD COUNTY, NORTH CAROLINA

Prepared By: U.S. Environmental Protection Agency

Region 4 Atlanta, Georgia

March 2011

10800455

INDEX

1.0 OBJECTIVE 1 2.0 SITE LOCATION AND DESCRIPTION 1 3,0 SITE HISTORY 2 4.0 DESCRIPTION OF SIGNIFICANT DIFFERENCE AND BASIS FOR THE

DIFFERENCE 3 4.1 A R S E N I C BIOAVAILABILITY STUDY 6

4.2 REVISED CLEANUP LEVEL FOR ARSENIC IN SURFACE SOILS 8

4.3 IMPACT OF THE REVISED CLEANUP LEVEL FOR ARSENIC IN SURFACE SOILS 10

5,0 AFFIRMATION OF STATUTORY DETERMINATIONS 10 6.0 PUBLIC PARTICIPATION ACTIVITIES 10

6.1 SUMMARY OF WRITTEN COMMENTS AND EPA'S RESPONSE II 6.2 ADMINISTRATPVE RECORD/INFORMATION REPOSITORY 14

FIGURE

FIGURE 1 Site Location Map

ATTACHMENTS

Attachment A February 08, 2011 Letter of Concurrence from North Carolina Department of Environment & Natural Resources

Attachment B Responsiveness Summary

ACRONYMS

ARARs bgs BHC BHHRA COCs DDE DDT DDD ESD EPA HI HQ LTM mg/kg NCDENR NPL ppm RA RBF RCRA RI/FS ROD UF-CEHT ^g/L

Applicable or Relevant and Appropriate Requirements below ground surface betahexachlorocyclohexane Baseline Human Health Risk Assessment Chemicals of Concern dichlorodiphenyldichloroethylene dichlorodiphenyltrichloroethane dichlorodiphenyldichloroethane Explanation of Significant Difference U.S. Environmental Protection Agency Hazard Index Hazard Quotient Long-Term Monitoring milligrams/kilogram North Carolina Department of Environment and Natural Resources National Priority List part per million Remedial Action relative bioavailability factor Resource Conservation & Recovery Act of 1976 Remedial Investigation/Feasibility Study Record of Decision Center for Environmental & Human Toxicology at University of Florida microgram per liter cubic yards

EXPLANATION OF SIGNIFICANT DIFFERENCE BARBER ORCHARD SUPEPO^UND SITE

WAYNESVILLE, HAYWOOD COUNTY, NORTH CAROLINA

1.0 OBJECTIVE

The function ofthis Explanation of Significant Difference (ESD) is to relate to all parties of concern that the U.S. Environmental Protection Agency (EPA) is modifying a component of the remedial action (RA) selected in the Record of Decision (ROD) signed on September 29, 2004 for the Barber Orchard Superfimd Site. In the 2004 ROD, the cleanup level for arsenic in surface soil was established at 40 milligrams per kilogram (mg/kg) or parts per million (ppm). This ESD modifies the cleanup level for arsenic in surface soil to 80 ppm. This ESD is required under Section 117(c) ofthe Comprehensive Environmental Response, Compensation, and Liability Act and Section 300,435(c)(2)(I) ofthe National Oil and Hazardous Substances Pollution Contingency Plan.

The 2004 selected remedy for soil for the Barber Orchard Superfimd Site includes the following:

• excavate the top foot of soil from contaminated property (the revised estimate is 80 acres) and dispose ofthe excavated soil off-site at RCRA Subtitle D landfill

• remove the underground distribution pipeline and associated contaminated soils and dispose of off-site

• take confirmatory samples from excavated areas to confirm concentration of contaminants in the remaining soil do not exceed their cleanup levels

• back-fill excavated areas with clean soil, grade, and re-vegetate • implement institutional controls (deed recordation and/or restrictive covenants) for those

contaminated properties not remediated.

A copy ofthis ESD and supporting documentation for this ESD will be added to the Barber Orchard Superfiind Administrative Record/Information Repository located at the Haywood County Public Library, 402 South Haywood Street, Waynesville, North Carolina and in EPA's, Region IV Information Center, Atlanta, Georgia. The Administrative Record/Information Repository can be accessed and reviewed by the public during normal working hours.

2.0 SITE LOCATION AND DESCRIPTION

The Barber Orchard Site is located off of Highway 74/23 approximately 3 miles west of the Waynesville city limits in western Haywood County, North Carolina (refer to Figure 1). The Site is approximately 438 acres in size located on the northern slope of a mountain.

The Site is a former apple orchard that operated from 1908 to 1988. Apples were grown commercially and harvested until bankruptcy closed the orchard. As with many commercial agricultural operations, pesticides were used. Pesticides suspected of being used at the Site include: lead arsenate, dichlorodiphenyltrichloroethane (DDT), gamma-

Barber Orchard Superfund Site E.\planation of Significant Difference

March 2011

betahexachlorocyclohexane (BHC) (better known as lindane), dichlorodiphenyldichloroethylene (DDE), dichlorodiphenyldichloroethane (DDD), endrin, and dieldrin. These pesticides were applied through an elaborate, predominantly underground piping system built throughout the orchard.

3.0 SITE HISTORY

In 1988, after bankruptcy, the bank holding the loan on the Orchard began selling tracts of land in various sizes. Ofthe 438 acres, approximately 100 acres have been developed into residential properties, 10 acres have been replanted with apple trees, 20 acres have been developed into church properties, approximately 30 acres have been developed as either commercial or light industrial property, approximately 30 more acres may be developed into commercial or light industrial property, and the remaining acreage, approximately 248 acres, is anticipated to be developed into residential properties. The average residential property ranges in size between Vz to 3 acres.

In early 1999, the Haywood County Health Department sampled the well of a concemed homeowner in Barber Orchard. Pesticides were detected in this sample, prompting a larger sampling effort by North Carolina Department of Environment and Natural Resources (NCDENR) and the North Carolina Department of Agriculture, Results ofthis sampling were forwarded to the EPA for removal action evaluation in June of 1999.

EPA conducted additional testing of residential soils and drinking water in Barber Orchard, Results show elevated concentrations of arsenic, lead, and pesticides in soil in many residential yards. Groundwater samples were collected from 55 potable water wells across the Site, Organochlorlne pesticides including alpha-BHC, beta-BHC, gamma-BHC (Lindane) and lead were detected in several ofthe wells.

A removal action was initiated in October 1999 and was completed by August 2000. This action removed surface soils (the top foot) from the manicured portion of 28 residential properties where arsenic levels exceeded 40 ppm. The excavated areas were backfilled with clean soil and re-landscaped. The residents in the Orchard were also encouraged to install filtration systems on their wells.

As observed during the emergency response, the underground distribution piping system remains in the ground. Pipes were often exposed during excavations. It was noted that a liquid leaked from one of these pipes and a sample ofthis liquid contained arsenic at 2,460 ppm and lead at 6,970 ppm. Consequently, the buried piping system can act as a continuing source of contamination.

The Barber Orchard Site was proposed for inclusion on the National Priority List (TvIPL) in the Federal Register on January 1, 2001 and was finalized on the NPL on September 13, 2001. The Site's EPA identificafion number is NCF FNO 406 989. The NPL is EPA's list ofthe most serious uncontrolled or abandoned hazardous waste sites identified for possible long-term remedial acfion under Superfiand.

Barber Orchard Superfund Site Explanation of Significant Difference

March 2011

4.0 DESCRIPTION OF SIGNIFICANT DIFFERENCE AND BASIS FOR THE DIFFERENCE

Although the former orchard occupies approximately 438 acres, the Remedial Investigation/Feasibility Study (RI/FS) expanded the study area to the edges ofthe watershed which covers an area of approximately 725 acres. The boundaries ofthe watershed are defined by the mountain top to the south, Richland Creek to the north, and two unnamed tributaries to Richland Creek, to the east and west. Included within the watershed boundaries are several businesses, the Saunook Fire Stafion, several churches, and a daycare center. This 725-acre area is drained by eight unnamed tributaries to Richland Creek. Figure 1 shows the location ofthe Barber Orchard Site.

The RUFS confirmed the presence of elevated concentrations of arsenic, lead and pesticides in the top foot of soil within the Orchard which results in unacceptable risks. The RI/FS also confirmed the presence of organochlorlne pesficides in the groundwater underlying the Orchard which also results in unacceptable risks. The unacceptable risks associated with the groundwater will be addressed in a future ROD.

The following chemicals were identified as chemicals of concern (COCs) in the soil: arsenic, lead, DDD, DDE, DDT, aldrin, dieldrin, endrin, and endrin ketone. These COCs are associated with one or more ofthe following exposure scenarios which resulted in an unacceptable risk:

• CURRENT/FUTURE RESIDENT - incidental ingestion of and dermal contact with surface soil, certain homegrown produce, overburden and bedrock groundwater;

• CONSTRUCTION WORKER - incidental ingesfion of, dermal contact with, and inhalation of subsurface soil, suspended particulates, overburden and bedrock groundwater;

• COMMERCIAL WORKER - incidental ingestion of, dermal contact with, and inhalation of overburden groundwater; and

• SPORTSMAN - fish ingesfion.

The issuance ofthe September 2004 ROD completed the RI/FS. The 2004 ROD requires the following acfions:

• Protect human health by reducing the amount of contaminated soils at the Site, • Excavate the top foot of an estimated 120 acres (developed and undeveloped acreage) (the

120 acres is based on an arsenic soil cleanup level of 40 ppm in the Orchard including the removal ofthe underground distribution pipeline and associated contaminated soils. o The excavated soil will be stabilized, if necessary, and then disposed of off-site at a

RCRA Subfifie D landfill), o Following confirmation sampling, the excavated areas will be back-filled with clean

soil, graded, and re-vegetated, o The underground pipeline and its contents will be excavated and disposed of off-site.

The sediment in the pipe will be sampled and any hazardous material will be disposed of off-site at a RCRA, Subtitle C landfill. If cost effecfive, the piping will be


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decontaminated and recycled.

• Implement institutional controls for those contaminated properties that are not remediated by this RA. Institutional controls include deed recordation, restrictive covenants, and a "Special Grant Condition". Cooperation ofthe property owner will be necessary to implement restrictive covenants. The State will be responsible for enforcing deed recordafions and restrictive covenants and Haywood County will be responsible for enforcing the "Special Grant Condition".

• If not all contaminated acreage is remediated, then a statutory five-year review will be necessary with the first review being completed within five years ofthe start ofthe remedial action.

In accordance to the 2004 ROD, the following activities are anticipated to take place as part ofthe RA:

This alternative involves removing the underground distribution pipeline and associated contaminated soils as well as excavating approximately the top foot of approximately 117 acres of the Orchard. Following the location of all underground utilifies, the underground pipeline, its contents, and any associated contaminated soils will be excavated and disposed of off-site, as appropriate. Testing the sediment in the pipeline will determine where and how this material will be disposed of (any hazardous material will be disposed of off-site at a RCRA Subfitle C landfill). The excavated soil (approximately 209,000 cubic yards (yd'')) will be tested to determine if treatment is needed. Treatment, if necessary, will be through the addition of a stabilizer such as fly ash or cement prior to transportation to an off-site Subtitle D landfill for disposal. Prior to backfilling an excavated area, confirmafion soil sample(s) will be collected and analyzed. Upon confirming an area has been cleaned, the excavated area will be back-filled with clean soil, graded, and re-vegetated. As part of this remedy, a soil staging area and decontamination area will be constructed.

If feasible, the piping will be decontaminated and recycled. If this is not a cost effective approach, then the piping will be sampled and disposed of accordingly.

If not accomplished during the design phase, additional sampling will be done prior to inifiafing excavafion efforts using X-ray Fluorescence (XRF) to better delineate surface soils requiring excavation based on the concentration of arsenic. In over 96% of the surface soils collected to date, if elevated COCs were present, arsenic was also present above 40 ppm. In only four samples did concentrations of organic pesticides exceed their cleanup level where arsenic was below 40 ppm. To insure the

Barber Orchard Superftind Site Explanation of Significant Difference

March 2011

remediation removes all contaminated soil, 30% of these XRF screening samples will be analyzed for all pesficides.

This alternative may also include the employment of institutional controls and the development/implementafion of a long-term monitoring (LTM) program for those contaminated soils that are not removed. The institutional controls will focus on those properties not cleaned up by this remedial action. The institutional controls considered are deed recordafion, covenant restrictions, and the Special Grant Condition. The purpose of deed recordation is to provide notice to potential purchasers of a property that it is contaminated. Restrictive covenants will be placed on property deeds, with the property owner's consent, on contaminated property that is not cleaned up by this remedial acfion. The restrictive covenants will protect neighboring properties and human health. EPA and NCDENR will work together implementing these institutional controls. NCDENR will be responsible for enforcing deed recordation and restrictive covenants. Haywood County will be responsible for enforcing the Special Grant Condition.

The 2004 ROD also established the following remedial action objectives:

Surface Soil and Sediment For Human Health: Prevent ingestion, inhalation, or direct contact with soil containing constituents at concentrations in excess of total hazard indices (HI) greater than 1 and/or a cumulative excess lifetime cancer risk of 1 X 10' for an onsite resident or onsite adolescent visitor.

Subsurface Soil For Human Health: Prevent ingestion, inhalation, or direct contact with soil containing constituents at concentrations in excess of total His greater than 1 and/or a cumulative excess lifetime cancer risk of 1 x 10" for an onsite construction worker.

The following surface and subsurface soil cleanup levels were established in the 2004 ROD:


March 2011

Contaminants of Concern

Cleanup Level^ in parts per million (ppm)

Basis for Selection

SURFACE SOILS/RESIDENTIAL SCENARIO

Aldrin Arsenic 4,4-DDD 4,4-DDE 4,4-DDT Dieldrin Endrin Endrin ketone Lead

0.033 40 2.4 1.7 1.7

0.035 15 1.5 400

1 X 10"*' cancer risk (BHHRA) 1x10'^ cancer risk (BHHRA) 1x10"*' cancer risk (BHHRA) 1 X 10-" cancer risk (BHHRA) 1x10"" cancer risk (BHHRA) 1x10"" cancer risk (BHHRA)

non-cancer risk (g HQ = 1 (BHHRA) non-cancer risk (@ HQ = 1 (BHHRA)

EPA Screening Guidance SUBSURFACE SOILS/RESIDENTIAL SCENARIO

Arsenic 4,4-DDT Endrin ketone

87 145 6.6

non-cancer risk (§ HQ = 1 (BHHRA) non-cancer risk (§ HQ = 1 (BHHRA) non-cancer risk (^ HQ = 1 (BHHRA)

parts per million (ppm) is equivalent to milligrams per kilogram (mg/kg) a - Risk-based values are back-calculated using the methodology and assumptions of

the Baseline Human Health Risk Assessment (BHHRA); "(§ 1 x lO"̂ " denotes the remedial goal option (clean-up levels) at a target incremental lifetime cancer risk of "1 X 10"̂ ", and "(^ Hazard Quotient (HQ) = 1" denotes the clean-up levels at a target hazard quotient of 1.

b - Current residential screening level for lead in residential soil.

The rationale for selecting 40 ppm as the cleanup level for arsenic is based on a review of the arsenic toxicity criteria. Instead of using the chronic reference dose and a hypothetical residential child receptor having a 6-year exposure duration of a child receptor, the 2004 ROD used the subchronic reference dose. Applying the subchronic reference dose of 5 x 10" mg/kg-day to a child receptor exposed for 6 years gives a preliminary remediation goal of over 300 ppm. However, because arsenic is a known human carcinogen by the oral route, the preliminary remediation goal was reduced to 40 ppm, representing a l x lO"'* cancer risk, and hence, protective for both the cancer and noncancer endpoints.

The cost ofthe Barber Orchard remedy, as described in the 2004 ROD, was estimated to be $19,000,000 - $20,000,000. This cost is based on excavating the top foot of soil across 120 acres and disposing ofthis soil [approximately 209,000 yd̂ or 313,500 tons (209,000 yd̂ x 1.5 tons/yd^)].

4.1 ARSENIC BIOAVAILABILITY STUDY

Since Site specific bioavailability data for the absorption of arsenic was not available in 2003 when the Baseline Risk Assessment was generated, a default value was used in the Agency's Superfund risk assessment process. For the bioavailability of COCs in soil, the default


March 2011

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value is 100 percent which means, ifa person ingests a teaspoon of soil, the Agency assumes that the person's body would absorb all ofthe arsenic in that teaspoon of soil.

In order to generate a Site specific bioavailability value for arsenic in Barber Orchard soil, EPA-Region 4 contracted with the Center for Environmental & Human Toxicology at University of Florida (UF-CEHT) to conduct a study to measure how much ofthe arsenic in the Barber Orchard soil is bioavailable using primates (adult male cynomolgus monkeys). The use of cynomolgus monkeys was elected over juvenile swine (pigs) as the characteristics ofthe cynomolgus monkey's gastrointestinal tract more closely resemble the human gastrointestinal tract. The study was entitled. Relative Bioavailability of Arsenic from Soil (August 2009) for the Barber Orchard Superfund Site.

EPA sent eight (8) soil samples collected from the Orchard to UF-CEHT. The 8 soil samples were designated MS-1, MS-2, MS-3, MS-4, MS-5, MS-6, MS-7, and MS-8. Small aliquots from four (4) of these soil samples were fed to the monkeys over numerous months. The study's experimental protocols and quality assurance and quality control requirements can be found in the July 2007 document entitled. Measurement of Relative Oral Bioavailability of Arsenic from Barber's Orchard Site Contaminated Soil Using Cynomolgus Monkeys. All necessary and required precautions were taken to ensure these animals were not harmed during or as a result ofthis study. Details regarding animal care and treatment can be found in Appendix B ofthe 2009 report. The concentrations of arsenic in the 4 soil samples used in this study are shown in the table below.

Concentration of Arsenic in parts per million (ppm) Soil Sample MS-1 MS-4 MS-5 MS-8

Whole Soil 280 300 370 310

Sieved Soil 290 388 382 364

The relative bioavailability of arsenic from the soil was determined by comparing the amount of urinary arsenic excreted by the monkeys following the ingestion of contaminated soil to the amount of urinary arsenic excreted following the ingestion of a dose of arsenic in water. For mass balance purposes, the amount of arsenic in fecal material was also measured.

The relative bioavailability of arsenic for the 4 soil samples are shown below:

Relative Bioavailability of Arsenic from Soil Soil Sample MS-1 MS-4 MS-5 MS-8 Average

Relative Bioavailability 0.33 ± 0.05 0.28 ±0.03 0.38 ±0.07 0.25 ±0.05 0.31 ±0.03

Barber Orchard Superfiind Site Explanation of Significant Difference

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The above data shows that only 25 to 38 percent ofthe arsenic in the Barber Orchard soil is bioavailable. Using the above relative bioavailability factors (RBF), the soil cleanup level for arsenic was adjusted by using the following equation:

C, (S-adjusted) = c (S-unadjusted) -RBF

where: C(S-adjusted) = Ncw soil clcanup level adjusted for relative bioavailability

factor C(s-unadjusted) = Current soil cleanup level RBF = upper limit ->- 0.38

lower limit —+ 0.25

The range for the adjusted cleanup level for arsenic becomes:

for a RBF of 0.38

for a RBF of 0.25

40 ppm-0.38 = 105 ppm

40 ppm-0.25 = 160 ppm

In addition to the study conducted by UF-CEHT, a similar bioavailability study (also sponsored by EPA) was conducted by the Veterinary Medical Diagnostic Laboratory, College of Veterinary Medicine, at the University of Missouri under contract to EPA. This study used juvenile swine (pigs) and the two reports generated from this effort are entitled, Relative Bioavailability of Arsenic in Barber Orchard Soil MS-1 (March 20, 2009) and Relative Bioavailability of Arsenic in Barber Orchard Soil MS-5 (March 20, 2009). The relative bioavailability of arsenic for these two soil samples are shown below:

Relative Bioavailability of Arsenic from Soil Soil Sample MS-1 MS-5

Relative Bioavailability 0,33 0.51

As can be seen, the results for sample MS-1 are the same for both studies. However, there is some difference for the results for sample MS-5 between the two studies.

Using the RBF of 0.51, the adjusted cleanup level becomes 40 ppm-0.51 = 78 ppm

4.2 REVISED CLEANUP LEVEL FOR ARSENIC IN SURFACE SOILS

The cancer risk associated with the original arsenic cleanup level for soil (40 ppm) is 1 x 10" . This means 1 person out of 10,000 has a greater possibility of developing cancer over their life due to the long-term exposure to the arsenic in these soils. However, this cleanup level was based on using the risk assessment bioavailability default value that 100% ofthe arsenic in the soil was bioavailable.

Baibcr Orchard .Superriind .Site E.xplanation of Signil'icanl Difference

March 2011

Based on the results ofthe UF-CEHT bioavailability study, an arsenic cleanup ievel between 105 ppm and 160 ppm will result in the same cancer risk level of 1 x 10" as the study verified that not all ofthe arsenic in the soil at Barber Orchard is bioavailable. However, to be conservative, this ESD increases the arsenic soil cleanup level from 40 ppm to 80 ppm. Due to the range of Site specific relative bioavailability factors, the estimated excess cancer risk tbr arsenic in the soil at the Barber Orchard Site at a concentration of at 80 ppm ranges from 5x10'^ to 8 X 10'"" (this range is less thanl •< IO"'').

The non-cancer hazard associated vvith the soil cleanup level of 40 ppm for arsenic, assuming 100% bioavailability, is a hazard quotient (HQ) of 0.5 (less than 1). Using the results ofthe UF-CEHT bioavailability study, the non-cancer hazard associated with an arsenic soil cleanup level of 80 ppm the HQ is still 0.5, since the bioavailability applies to both the carcinogenic and noncarcinogenic endpoints.

The cleanup levels for all the other COCs remain the same accept for arsenic. The table below lists the current cleanup levels.

Cleanup Levels for Chemicals of Concern in the Surface and Subsurface Soils at Barber Orchard Superfund Site

Contaminants of Concern

Cleanup Levef' in parts per million (ppm)

Basis for Selection

SURFACE SOILS/RESIDENTIAL SCENARIO

Aldrin

Arsenic

4,4-DDD

4,4-DDE

4,4-DDT

Dieldrin

Endrin

Endrin ketone Lead

SUBSURFACE SOILS/

Arsenic 4,4-DDT

Endrin ketone

0:033

80

2.4

1.7

1.7

0.035

15

1.5 400

1 X 10"" cancer risk (BHHRA) 5 X 10"= cancer risk (BHHRA)

1 X 10"" cancer risk (BHHRA)

1 X 10"" cancer risk (BHHRA)

1 X 10"̂ cancer risk (BHHRA) 1 X 1Q-" cancer risk (BHHRA)

non-cancer risk (g HQ = 1 (BHHRA)

non-cancer risk (g HQ = 1 (BHHRA)

EPA Screening Guidance RESIDENTIAL SCENARIO

87 145

6.6

non-cancer risk (2̂ HQ = 1 (BHHRA) non-cancer risk @ HQ = 1 (BHHRA)

non-cancer risk @ U Q = \ (BHHRA)

parts per million (ppm) is equivalent to milligrams per kilogram (mg/kg) a - Risk-based values are back-calculated using the methodology and assumptions of

the Baseline Human Health Risk Assessment (BHHRA); "@ 1 x 10"^" denotes the remedial goal option (clean-up levels) at a target incremental lifetime cancer risk of "1 X 10"^", and "@ Hazard Quotient (HQ) = 1" denotes the clean-up levels at a target hazard quotient of 1.

b - CuiTcnt residential screening level for lead in residential soil.

Barber Orchard Supcrlbiid Site Explaiialiun ol'Significant Difference

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4.3 IMPACT OF THE REVISED CLEANUP LEVEL FOR ARSENIC IN SURFACE SOILS

Changing the arsenic cleanup level from 40 ppm to 80 ppm will result in a reduction of acreage requiring cleanup. As stated above, the 2004 ROD estimated 120 acres required cleanup. Employing the 80 ppm cleanup level for arsenic, the acreage requiring remediation is expected to decrease to approximately 90 acres. This acreage was further reduced to 80 acres as the result ofthe analytical data generated by the sampling strategy implemented by EPA during the spring and summer of 2010. The results ofthis sampling effort can be found in the report entitled, Remedial Design Investigation for the Barber Orchard Superfund Site, Waynesville, North Carolina (October 2010).

Using an arithmetic ratio, reducing the acreage to be cleaned up by a fourth equates to a reduction of one-fourth in the cost to implement this remedy. Therefore, the estimated new cost ofthe cleanup ranges between $14,250,000 - $15,000,000. This cost is based on excavating the top foot of soil over 80 acres and disposing of approximately 127,374 yd̂ or 191,061 tons (127,374 yd' x 1.5 tons/yd^) of soil.

5.0 AFFIRMATION OF STATUTORY DETERMINATIONS

The Agency and NCDENR believe that this change to the selected remedy does not alter the protectiveness for human health and the environment, compiles with Federal and State requirements that are applicable or relevant and appropriate to this reniedial action, and is cost-effective.

NCDENR concurs with this change (refer to Attachnient A).

6.0 PUBLIC PARTICIPATION ACTIVITIES

Over 800 fact sheets were mailed to the public on November 30, 2009 to inform the public ofthe Agency's proposal to increase the cleanup level for arsenic from 40 ppm to 80 ppm. Not only did this Fact Sheet provide the supporting rationale for proposing this change, it also informed the public of a public availability session which was held on Tuesday, December 8, 2009. The public availability session was held at the Saunook Fire Station from 2:00 to 8:00 p.m. and representatives from EPA and NCDENR were available between these hours to address any questions/concerns. Twelve citizens attended the availability session as well as camera crew from the television station WLOS-13. The public availability session also initiated the 30-day public comment period on the proposed change to the arsenic cleanup level. The public comment period closed on January 8, 2010, 30 days after the public availability session.

The primary comment/question expressed by individuals who attended the availability session was, "When will the actual cleanup occur?"


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Prior to the public availability session, EPA also conducted a conference call with North Carolina Department ofHealth and Human Services and the Haywood County Health Department, in an attempt to address their concerns.

Three sets of comments were received during the 30-day, one from North Carolina Department ofHealth and Human Services/Division of Public Health/Epidemiology Section/Occupational and Environmental Epidemiology Branch, one from the Haywood County Health Department, and one from Clean Water for North Carolina. The comments from the Haywood County Health Department mirror those prepared by North Carolina Department of Health and Human Services/Division of Public Health. The three sets of comments express concern about making the proposed change and requested EPA to reconsider making the proposed change to the arsenic cleanup level. Copies of these comments are included in Attachment B.

6.1 SUMMARY OF WRITTEN COMMENTS AND EPA'S RESPONSE

The following summarizes the concerns expressed in written comments received by EPA during the comment period:

1) Due to the proposed change, 30-acres ofthe Orchard will not be remediated leaving in place soil with concentrations of arsenic between 40 ppm and 80 ppm and this may put future residents at risk.

2) Concerns about the methodology ofthe two bioavailability studies, 3) The use ofthe results of animal studies to predict the effect on the human population. 4) The proposal does not take into account the potential presence of other pesticides in soil

and the bioavailability of these pesticides in humans. 5) The bioavailability study using cynomolgus monkeys fails to take the variability in the

human population. 6) Questions the use of Site specific data in EPA's risk assessment process versus using

the default values in EPA's risk assessment when Site specific data is not available. 7) EPA's priorifization for the cleanup ofthis Site. 8) Correlation between arsenic bioavailability in primates and swine and that in humans

and the increasing the arsenic cleanup level from 40 ppm to 80 ppm is not erring on the side of safety.

9) The use of arsenic as the single parameter to drive cleanup decisions. 10) Consider the impact ofthe continual leaching of contaminants from the 30-acres that

will not be remediated due to increasing the arsenic cleanup level from 40 ppm to 80 ppm into the adjacent areas.

The following is a summary of EPA's response to the above ten (10) comments. A response to each individual comment can be found in Attachment B.

Response to Comment #1: The comment is correct in stating that by increasing the arsenic cleanup level from 40 ppm to 80 ppm, the areal extent ofthe soil cleanup will be reduced leaving behind concentrations of


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arsenic in the soil between 40 ppm and 80 ppm. However, as shown above, a concentration of 80 ppm of arsenic in the surface soil equates to a cancer risk range of 5 x 10"̂ to 8 x 10"̂ and a hazard quotient (HQ) of 0.5, EPA's acceptable cancer risk range is 1 x IO'"* to 1 x 10" and EPA's acceptable non-cancer hazard is less than 1. In addition, prior to preparing the Scope of Work for the RA, the Agency resampled all acreage proposed for remediation. This sampling effort consisted of collecting two 5-aliquot composite soil samples from each quarter acre. One composite sample represented the surface soils (i.e., top foot of soil) and the second composite sample was collected from 12 inches below ground surface (bgs) to 18 inches bgs. The analytical results ofthe second soil sample were used to define the vertical extent soil contamination and confirm that the underlying soils are clean. The term "clean" implies "allows for unlimited use and unrestricted exposure". All samples will be analyzed for the COCs.

Response to Comment #2: According to the lead researcher at UF-CEHT, pharmacokinetics studies that rely on primates like the Barber Orchard Bioavailability Study, typically use 3-5 animals per group. The Barber Orchard study used 4 animals and one animal as a control, therefore the number of animals in the Barber Orchard study is well within the norm for primate studies.

Response to Comment #3: It is the Agency's position that this comment is the commenter's personnel opinion as the commenter did not cite any specific scientific literature. Some ofthe research work conducted by UF-CEHT with primates on arsenic absorption and excretion values is nearly identical to observations from human volunteers (Roberts et al. Tox. Sei. 67:303-31-, 2002). The important idea is that the information sought is relative bioavailability (soil versus water), not absolute bioavailability. There is no data in humans for relative bioavailability of arsenic from soil to compare with animal studies. The best that science can do is to get information from well conducted studies using animals whose gastrointestinal tract characteristics closely resemble the human gastrointestinal tract. In addition there is some comparability ofthe results between species (monkey versus swine).

Response to Comment #4: The Agency's Superfund risk assessment process is designed to calculate the overall risk posed by a Site. This process includes looking at all appropriate exposure pathways as well as all chemicals identified as chemicals of concern. The overall goal ofthe remedial action is to achieve a level of cleanup that allows for unrestricted use and unlimited exposure after the remediation.

Response to Comment #5: EPA's Superfund risk assessment process does take the variation in the human population into account. This risk assessment process is very conservative and errors on the side of being protective.

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Response to Comment #6: It is the Agency's position that Site specific data is always preferable over default values. However, due to the high cost and length in time to develop Site specific data, the Agency developed and adopted default values to be used in the risk assessment process in the event that Site specific data was not available. However, the bioavailability study provides Site specific data.

Response to Comment #7: In August 1995, EPA established the National Risk-Based Priority Panel to evaluate the risk at NPL sites with respect to human health and the environment. The Agency uses these evaluations to establish funding priorities for all new cleanup construction projects in the Superfiind program. This national approach is intended as a way for each Region to list its priority projects and rank these projects against priority projects from other Regions, ensuring that resources are allocated to the projects posing the most risk to human health and the environment.

This systein allows for an evaluation of projects based on the following principles: Protection of human health; Protection from significant environmental threats; and Potential human health or environmental threats based upon current site conditions.

Five criteria and associated weighting factors are used to compare projects based on common criteria. These include risks to human populafion exposed, contaminant stability, contaminant characteristics, threat to a significant environment, and program management considerations. The Nafional Risk-Based Priority Panel is comprised of national program experts from Regional offices and Headquarters.

The Region originally presented the Barber Orchard Site to this panel in 2003 and again in 2006. The Site was ranked in the middle; however, the Region informed the panel of its intention to conduct the arsenic bioavailability study so funding the RA was placed on hold until after the completion ofthe arsenic bioavailability study. After the issuance ofthis ESD, the Region will again have this Site re-instated on the fiinding priority list.

Response to Comment #8: Refer to Response to Comment #3 above regarding the concern about the correlation between arsenic bioavailability in animals and that in humans and the Response to Comment #1 regarding not erring on the side of safety.

Response to Comment #9: Ultimately, the Agency is not using a single parameter to drive the cleanup. In the near fiiture, the Agency will be refining the areas to be excavated based on all COCs. The Agency selected arsenic as the driver due to the following rationale:

In over 96 percent ofthe surface soils collected to date, if elevated COCs were present, arsenic was also present above 40 ppm. Based on this observation, the


March 2011

14

following fact became evident, wherever elevated concentrations of contaminants were detected, elevated levels of arsenic were always present. Therefore, in the 2004 ROD, the Agency elected to use the concentration of arsenic as the driver for the soil cleanup.

Response to Comment #10: If leaching (vertically and/or horizontally) was an active mechanism for the movement of contaminants at the Site, then elevated levels of Site related contaminants would have been detected in the surface water/sediment in the streams that drain the Site. Below is an excerpt from the RI,

"Although several inorganic analytes were detected at levels above background concentrations and National Recommended Water Quality Criteria (EPA, 1999), arsenic was not detected in surface water and lead was detected only at low concentrations (3.0 microgram per liter (|Jg/L) to 4.7 fig/L). Detections of organic pesticides exceeding federal surface water criteria include heptachlor, alpha-BHC, beta-BHC, and 4.4-DDT. The detection of 4.4-DDT is from a location in Richland Creek immediately downstream of the watershed, and the remainder of the detections are located within the footprint of the former orchard. Most of the detections occur in one stream (Stream D) that drains the area where pesticides were mixed before application. Also note that this location is where subsurface soils were most contaminated, suggesting that leaching from the contaminated soils is a possible source to surface water."

The surface soils along Stream D are to be remediated as part ofthe soil cleanup effort.

6.2 ADMINISTRATIVE RECORD/INFORMATION REPOSITORY

This ESD will be added to the Barber Orchard Site Administrative Record/Information Repository. The Site's Administrative Records/Information Repositories are kept at:

Haywood County Public Library 678 South Haywood Street Waynesville, North Carolina 828-452-5169 Hours: Mon, Tues, Wed, & Fri: 9:00 am - 6 pm

Thur, 9:00 am-7:00 pm Sat, 9:00 am-5:00 pm

and

15

U.S. Environmental Protection Agency Region IV - Records Center 61 Forsyth Street Atlanta, Georgia 30303 http://r4intranet.epa.gov/r41ibrarv/index.htm 404-562-8190


March 2011

These records are available for public review during normal working hours.

"franklin E. Hill, Director Superfiind Division

Lj/l/ / i7/ / Date

http://r4intranet.epa.gov/r41ibrarv/index.htm

FIGURE

Haywood County

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Nortt iCc

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\j!i^2r~\>-~rZ-Z —

rolina

1 f [ r~̂ y 'Ov^^X

^^A^^^W)

"^^^S^ < ^ > ^

LEGEND Roads

/ \ / Streams

Watershed

" K Town

0 1500 Feet

Figure 1 Barber Orchard Location Map

Barber Orchard Haywood County, NC

ATTACHMENT A

FEBRUARY 08,2011 NORTH CAROLINA DEPARTMENT OF

ENVIRONMENT & NATURAL RESOURCES

Letter of Concuirence

^ ^

NCDENR North Carolina Department of Environment and Natural Resources

Division of Waste Management

Beverly Eaves Perdue Dexter R. Matthews Dee Freeman

Governor Director Secretary

08 February 2011

Mr. Jon Bomholm Superfiind Branch, Waste Management Division US EPA Region IV 61 Forsyth Street. SW Atlanta, Georgia 30303

SUBJECT: Concurrence with Explanation of Significant Difference Barber Orchard Waynesville, Haywood County

Dear Mr. Bomholm:

The State of North Carolina by and through its Department of Environment and Natural Resources, Division of Waste Management (herein after referred to as "the state"), reviewed the Explanation of Significant Difference (ESD) received by the Division on 04 February 2011 for the Barber Orchard Site and concurs with the selected remedy, subject to the following conditions:

1. State concurrence on the ESD for this site is based solely on the information contained in the ESD received by the State on 04 Febmary 2011, Should the State receive new or additional information which significantly affects the conclusions or amended remedy contained in the ESD, it may modify or withdraw this concurrence with written notice to EPA Region IV.

2. State concurrence on this ESD in no way binds the State to concur in future decisions or commits the State to participate, financially or otherwise, in the cleanup ofthe site. The State reserves the right to review, overview comment, and make independent assessment of all fiiture work relating to this site.

1646 Mail Service Center, Raleigh, North Carolina 27699-1646 M9!rt-hr'c»rr>rnci Phone: 919-508-8400 \ FAX: 919-7154061 \ Internet: www.wastenotnc.org IN 01111 L^aiOl ina

An Equal Opportunity \ Affirmative Action Employer J^atumlly

http://www.wastenotnc.org

3, If, after remediation is complete, the total residual risk level exceeds 10"*, the State may require deed recordation/restriction to document the presence of residual contamination and possibly limit future use ofthe property as specified in NCGS 130A-310.8

The State of North Carolina appreciates the opportunity to comment on the ESD and looks forward to working with EPA on the remedy for the subject site. Ifyou have any questions or comments, please call Mr. Nile Testerman at 919 508-8482,

Sincerely,

Dexter R. Matthews, Director Division of Waste Management

cc: Jack Butler, Chief NC Superfund Section David Lown, NC Superfund Nile Testerman, NC Superfimd

1646MailServiceCenter, Raleigh, North Carolina 27699-1646 sP'̂ ^ un T Phone: 919-508-8400 \ FAX: 919-715-4061 \ Internet: www.wastenotnc.org iNortnL-arOlina

Jyatumllij An Equal Opportunity \ Affirmative Action Employer

http://www.wastenotnc.org

ATTACHMENT B

RESPONSIVENESS SUMMARY

Three sets of comments were received during the 30-day, one from North Carolina Department ofHealth and Human Services/Division of Public Health/Epidemiology Section/Occupational and Environmental Epidemiology Branch, one from the Haywood County Health Department, and one from Clean Water for North Carolina. The comments from the Haywood County Health Department mirror those prepared by North Carolina Department of Health and Human Services/Division of Public Health. Copies of these comments are included below along with EPA's response.

Norrh C.irolin» Department of Health aud Unman Services Division of Public Health • CpiJemiology Secliou

Occupational and Environmenlal Epidemiology Branch 1912 Mall Service Center • Raleigh, North Carolina 27699-1912

Tel 919-707-5900 • Fax 919-870-4810 Beverly l.'̂ aves I'ertjue, Cti.">\'einor Jcfl'icy P. r.ngel. M.!."). (..atijcr M. (^iiiislcr. Sccrciiin- .Srate Mciillh l.')irct:[t)r

January 9, 2010

MEIMORANDUM

TO: Jon Bomholm, Environmental I'roieciion Agency, Region IV

FROM: Kenneth Riido, Ph.D. Toxicoiogist, Nonh Carolina Division of Public Health ../h

SUBJECT: North Carolina Division of Public Heallh Comments Regarding IZP.A's Proposed Change in the Soil Clean Up Level lor Arsenic at thc Barber's Orchard Superfund Site in Waynesville, Noiih Carolina

Introduction: The North Carolina Division ofPublic Health (NCDPH) would like to put forward comments regarding the above EPA proposed change to arsenic soil clean up levels at the Barber's Orchaid Superfund Site.

Comnienis:

liPA has proposed changes to the arsenic soil clean up levels at Barber's Orchard from 40ppm to 80ppm. Ihe NCDPH has concerns from a public heatth protective standpoint regarding this change because it may put future residents at a higher risk than would have occurred wilh the original cleanup level of 40 ppm. The reason for this concern centers upon the 30 acres that EPA will clean up lo a higher concentration of arsenic that poses an increased human health risk from arsenic exposure to levels exceeding the current EPA aclion level of 40ppm. Arsenic is a known human carcinogen that can cause various types of cancer in humans at low levels ofexposure. 40ppm in soil represents a lifetime human cancer risk of 1 in 10,000. A change to a clean up level to 80ppm for arsenic in soil increases the cancer risk to I in 5000. Public health protective levels utilized by NCDPH for arsenic in soil are lower than EPA's 40 ppm arsenic clean up level and EPA's 40 ppm clean up level is also considerably lower than the EPA regional arsenic levels in soil that represent a 1 in 1,000,000 lifetime cancer risk. Biised on these heallh protective levels, thc use of 80 ppm represents an unacceptable human exposure level for residents in NC living on land with arsenic soil levels above 40 ppm. Trom the viewpoint

Morth Carolina Public H«alili 'k i r^ fer a hcal'Jticr i n j i a t e r NatthCi>«li frvwhCFE. Lvrrvdir Ivcrfbody m^

Location: 5505 Six Forki Road A hloiir. Rnom O-l • Knigigli, N.C. 27609

of NCDPH, EPA's clean up levels come with an elevated human cancer risk that we believe based on the proposed EPA changes is not advisable from a general public health protection standpoint. The EPA proposed change to the arsenic soil clean up level at the Barber's Orchard Superfund Site is based upon the results of 2 studies using cynomolgus monkeys and juvenile swine. These studies indicated a relative bioavailability of arsenic from Barber's Orchard soil ranging from 25 to 51 percent. NCDPH has some methodological concerns with these 2 studies. For example, NCDPH questions the use of only 2 soil samples in the juvenile swine study versus 4 samples in the cynomolgus monkey smdy and the small number of animals used in each study. NCDPH's primary concerns are over the use of these animal studies to predict the bioavailability of arsenic in Barber's Orchard residents with arsenic contaminated soil levels exceeding 40 ppm. In general, the scientific literature and in particular the voluminous human data base for arsenic has indicated that animal studies have been poor predictors of human health risks for cancer and non cancer endpoints as well as for human exposure/metabolism/absorption/excretion. Although studies ofthe bioavailability of arsenic suggest that the absorption of arsenic in ingested soil or dust is less than the absorption from ingested salts, there are clearly differences in humans compared to animals. Human data reports absorption percentages of arsenic that are higher than in animals, including the 2 animals in the EPA studies used in their proposed arsenic soil level change. Based on this information, to assume that human bioavailability will be the same as in these 2 animal studies when literature reports indicate human arsenic absorption to be higher than these 2 animals is a concern. To make a cleanup level change for future residents ofthe 30 acres in Barber's Orchard based on animal data that clearly would not be applicable to humans and that may actually underestimate human exposure represents a poorly thought out scientific approach that may not be protective of human health. EPA's proposal does not take into account the other pesticide contaminants in the soil at this site in terms of their bioavailability to humans. EPA's proposal does not take into account the potential effect that the presence ofthe other pesticides may have on the actual arsenic human bioavailability. EPA's proposal does not take into account the additional lifetime cancer risk posed by the additional pesticides in the soil at this site. EPA simply makes the assumption that arsenic soil levels vvill be "driver" for the soil cleanup. This is poor public health protection policy, especially in light ofthe scientifically based problems that exist with using the 2 animal studies in assuming human arsenic bioavailability, and the added human cancer risk attendant to this scientifically fiawed approach, in addition to the additional human cancer risk from the other pesticides in the soil. The animal studies do not take into consideration human interindividual variation. EPA is assuming that every person who may live on the Barber's Orchard 30 acres that will not be cleaned up in their proposal will have the same bioavailability to arsenic in soil that the cynomolgus monkeys and juvenile swine have. This clearly would not be the case and certainly is not justifiable by EP.A based on the increased human absorption compared to animals and interindividual variation in humans, where some people may have levels of absorption from the arsenic in the soil much higher than the levels in the animal studies as well as much higher than their fellow humans that may live on the 30 arsenic contaminated acres that will not be cleaned up by EPA in their proposal EPA has up to this point in time assumed 100 percent availability of arsenic in soil for humans as a default in their risk assessments and does not appear to be proposing to change this at this time or at any time in the near fiiture. Changing this default on a site by site basis using animal studies with soil from a specific site has not been sufficient proof for EPA to adjust soil bioavailability percentages as a risk assessment policy for superfiind cleanup across the country and is not justified for arsenic in particular based on the poor predictability of animal data for human health effects from arsenic exposure. While it is certain that human bioavailability of arsenic from soil is not 100 percent, it is probable that it is above the 25-51 percent seen in the animal studies. Using this animal data for Barber's Orchard specifically is not accurate based on the .scientific literature comparing human absorption to animals and the fact that human interindividual variation is not being taken into consideration by EPA,in this proposal. It is NCDPH's opinion based on this information that the use of EPA proposed arsenic soil clean up

level may result in an increased human cancer risk over and above the already increased cancer risk that NCDPH finds unacceptable in Barber's Orchard from the levels of arsenic and other pesticides in the soil at this site.

Conclusion:

Based on the above comments, NCDPH recommends that EPA not use the proposed arsenic soil clean up level of 80 ppm.

If EPA overrules the concerns and recommendation of NCDPH in this matter, NCDPH strongly recommends safeguards be put into place by EPA and the Haywood County Health Department that restricts human exposure and development on the 30 acre tract ofthe Barber's Orchard Superfiind Site that would not be cleaned up under EPA's proposal in order to protect public health from exposure to arsenic and the other pesticides in the soil at this site.

The following are EPA's responses to the above comments from North Carolina Department ofHealth and Human Services/Division ofPublic Health:

Response to First Comment: The coimnenter states that "40 ppm represents a lifetime human cancer risk of 1 in 10,000". This relationship is based on the arsenic in the soil being 100 percent bioavailable. However, has shown through the primate study, only 25 to 38 percent on the arsenic is bioavailable. Therefore, changing the cleanup goal from 40 parts per million (ppm) to 80 ppm does not result in an increase in the cancer risk to 1 in 5,000 as stated in the comment. At a cleanup goal of 80 ppm, the lifetime cancer risk associated with the arsenic is 2 x IO"'* which is within the EPA's acceptable risk range. EPA's acceptable risk range is 1 x 10' to 1 ^ 10" .

Response to Second Cotnment: According to the lead researcher at UF-CEHT, typically, pharmacokinetics studies relying on primates use 3-5 animals per group and therefore this number of animals in the Barber Orchard study is well within the norm for primate studies. The Region's risk management decision is based on the findings ofthe primate study and not the swine study. Therefore, the Region is relying on the results of four soil samples in the primate study to support the change in the cleanup goal for arsenic.

Response to Third Comment:' It is the Agency's position that this comment is the commenter's persomiel opinion as the cominenter did not cite any specific scientific literature. Some ofthe research work conducted by UF-CEHT with primates on arsenic absorption and excretion values is nearly identical to observations from human volunteers (Roberts et al. Tox. Sei. 67:303-31-, 2002). The important idea is that the information sought is relative bioavailability (soil versus water), not absolute bioavailability. There is no data in humans for relative bioavailability of arsenic from soil to compare with animal studies. The best that science can do is to get information from well conducted studies using animals whose gastrointestinal tract characteristics closely resemble the human gastrointestinal tract. In addition there is some comparability ofthe results between species (monkey versus swine).

Response to Fourth Comment: The Agency's Superfijiid risk assessment process is designed to calculate the overall risk posed by a Site. This process includes looking at all appropriate

exposure pathways as well as all cheinicals identified as chemicals of concein. The overall goal ofthe RA is to achieve a level of cleanup that allows for unrestricted use and unlimited exposure after the remediation. The following table is a condensed version of Table 18 from the 2004 ROD enfitled "Cleanup Levels for Chemicals of Concern in the Surface and Subsurface Soils". As can be seen, a cleanup goal has been established for each chemical of concern.

Contaminants of Concern Cleanup Level in parts per

million (ppm) SURFACE SOILS/RESIDENTIAL SCENARIO

Aldrin Arsenic 4,4-DDD 4,4-DDE 4,4-DDT Dieldrin Endrin Endrin ketone Lead

0.033 40 2.4 1.7 1.7

0.035 15 1.5 400

SUBSURFACE SOILS/RESIDENTI.A.L SCENARIO

Arsenic 4,4-DDT Endrin ketone

87 145 6.6

Response to Fifth Coinment: EPA's Superfund risk assessment process does take the variation in the human population into account. This risk assessment process is very conservative and errors on the side of being protective.

Response to Comment #6: It is the Agency's position that Site specific data is always preferable over default values. However, due to the high cost and length in time to develop Site specific data, the Agency developed and adopted default values to be used in the risk assessment process in the event that Site specific data was not available.

Response to Final Cotnment: As stated above, the overall goal ofthe RA is to achieve a level of cleanup that allows for unrestricted use and unlimited exposure after the remediation. However, as the Agency is dealing with private property owners, there is a possibility that a property owner will not grant access EPA to their property for cleanup. If this situation does evolve, then the Special Grant Condition as explained in the 2004 ROD (Secfion 6.1 LAND USES, page 45) would become relevant. The County of Haywood has the responsibility of enforcing the Special Grant Condition.

HAYWOOD COHNTV HEALTH DEPARTMENT Main Offices

2177 Asheville Road. Waynesville. North Carolina 28786 Tciephoiic (828) •45:-<5<575

Kn vironmental Heal lb 1233 N. Main Si. Box X. Wayncvville. NC 28786

Telephone (828)452-6682

CanniiK F. Rocco, M . S . , Health Director

Jaimar> 7.2010

Mr. Jun Bomholm U.S. H P A - R e g i o n 4 61 Forsjlh Street, SW Atlanta. (Jeorgia J0.?03 - 3104

Dear Mr. Bomholm:

•fhe purpose ofthis krltcr is to provide public comments conceming the proposed change in soil cleanup level for arsenic at Barber Ocliard Superfund Site. Waynesville, NC as described in Ihe F.PA Fact Sheel dated October 20W.

The Haywood County Heallh Department and Board of I Icahh has been involved with the soil and water contamination issue at Barber Orchard since 1999. We are signiFicantly concerned about the cleanup and public heallh impact ofthe pesticide cmilaniinalion at this Superfund site. Ihe change in soil cleanup levels is a signit'icanl departure from thc original action level of JO parts per million (ppm I of arsenic and raises thc limit to 80 ppm. resulting in .^0 fewer aca-s being clenned of arsenic and tuher pesticide contaminants.

We have reviewed thc North Carolina Division ofPublic lieahh's (NCDPH) comments regarding changes in the arsenic cleimup levels. We share many ofthe same concerns, specifically; we are concemed about thc melhodologv' used to ju.stit> changing the soil cleanup level of arsenic. The NCDPH questions thc scienlinu approach ascd lo make this change and tbe local health department relies on their expert advice and guidance when considering action or policy decisions in matters ofthis tvpe. Ihercfore. we would ask that the FP.A reconsider this change in cleanup level for arsenic.

The other area of concern we have involves the prioritization ofthis site on Ihe Superfund Site Action lisl. Some cleanup has been accomplished to date however, there is more to do. Plea.se provide us with the current prioriti7Jition level for this site and additional information regarding the priorili/aiitm process si> we understand who and how rankings are established and changed. Given data on the level. e.Ktent and time the contamination has been at this site, we would strongly urge thc bPA to elevate the prioritization level of Barber Orchard so that cleanup lakes place within thc year.

Thank you for your consideration of our concerns and requests.

Sincerely. . --j

I,vnisc Paschke, Board ofMeahh Chair Carmine F. Rocco. Health Director

"Promoling Healthy Ulestytes"

http://Plea.se

Only the comment expressed in the last paragraph ofthe Haywood County Health Department's letter is addressed below.

Response to Comment: In August 1995, EPA established the National Risk-Based Priority Panel to evaluate the risk at NPL sites with respect to human health and the environinent. The Agency uses these evaluations to establish funding priorities for all new cleanup construction projects in the Superfiand program. This national approach is intended as a way for each Region to list its priority projects and rank these projects against priority projects from other Regions, ensuring that resources are allocated to the projects posing the most risk to human health and the environment.

This system allows for an evaluation of projects based on the following principles: Protection of human health; Protection from significant environmental threats; and Potential human health or environmental tlireats based upon current site conditions.

Five criteria and associated weighting factors are used to compare projects based on common criteria. These include risks to human population exposed, contaminant stability, contaminant characteristics, threat to a significant environment, and program management considerations. The National Risk-Based Priority Panel is comprised of national program experts from Regional offices and Headquarters.

The Region originally presented the Barber Orchard Site to this panel in 2003 and again in 2006. The Site was ranked in the middle, however, the Region informed the panel of its intention to conduct the arsenic bioavailability study so funding the RA was placed on hold until after the completion ofthe arsenic bioavailability study. After the issuance ofthis ESD, the Region will again have this Site re-instated on the funding priority list.

January 5,2010

Mr. Jon Bomholm U.S. EPA-Region 4 61 Forsyth Street, SW Atlanta, Georgia 30303-3104

Dear Mr. Bornholm,

On behalf of Clean Water for North Carolina, I would like to submit thc following comments on the proposed change to the .soil cleanup level for arsenic at the Barber Orchard Superfund Site (EPA IDU NCF FNO 406 989). After reviewing the details ofthe 2004 Record of Decision and the results ofthe Arsenic Bioavailability Study as presented in the Proposed Explanation of Sigjiificant Difference Fact Sheet, we have several coneems regarding the proposed change.

1. The results ofthe Arsenic Bioavailability Study do suggest decreased health risks from arsenic for the soil exposure pathway. However, CWFNC does not feel that these results merit an increa.sed soil cleanup level for arsenic. First, it is our concern that thc correlation between arsenic bioavailabilitj' in primates and swine, and that in humans has not been fully explored. Without this knowledge, thc estimates of arsenic bioavailability obtained through the Arsenic Bioavailability Study are not guaranteed to be accurate estimates ofthe human health risk at the site. Second, CWFNC supports the Agency's commitment to err on the side of safety when it comes to safe cleanup levels. However, thc new proposed soil cleanup level for arsenic, 80 mg/kg, does not err on the side of safety; it is higher than the highest adjusted cleanup level of 78 mg/kg. To better fulfill this commitment, we recommend that EPA maintain the current soil cleanup level, which ensures that soil arsenic levels are safe for residents.

2. Jn the past, CWFNC has questioned the appropriateness of using a single parameter (arsenic, in this case) to drive cleanup decisions for this site. In tliis situation, wc feel obliged lo point out the doubts caused by this method. ITie new cleanup level, if accepted, would reduce the acreage requiring cleanup from 120 acres to 90 acres, eliminating 30 acres which presumably have arsenic levels higher than 40 rag/kg but less than 80 mg/kg. While CWFNC understands that this reduction in acreage could save up to $5 million in federal fimding and realizes that there are many other sites on the NPL in need of these funds, we worry that thc 30 eliminated acres could contain elevated levels ofthe other chemicals of concern, resulting in unintended failure to meet remediation goals. We recommend careful monitoring of a// parameters prior to a change in the acreage included in the cleanup.

3. CWFNC commends the Agency's cifort to expand its study area fo the entire watershed surrounding the site. Due to the high volimie of contaminated soil on the site, contamination of nearby ground and surface water is probable. Although EPA's Fact Sheet did not report data from the larger 725-acre area included in the Remedial Investigation/Feasibility Study, comments at the Public Availability Session on

December 8 indicated that EPA found elevated levels of contamination outside the Superfund site's boundaries but within the larger study area. Although the surrounding acreage does not fall under EPA's jurisdiclion, there is potential for continual leaching and contamination of this area. It is vital that EPA consider the impact which eliminating 30 acres of contaminated soil from the cleanup effort could have on the continual leaching of toxic chemicals into adjacent areas.

Thank you for this opportunity to submit comments on the Proposed Explanation of Significant Difference Fact Sheet, We appreciate EPA's continued attention to this site and look forward to the initiation of remedial activities to create a safer environment for Haywood County residents.

Sincerely,

Katie Hicks Water Justice Organizer

And

Hope Taylor Executive Director

Response to First Comment: As stated earlier, there is no data in humans for relative bioavailability of arsenic from soil to compare with animal studies. The best that science can do is to get information from well conducted studies using animals whose gastrointestinal tract characteristics closely resemble the hunian gastrointestinal tract. In addition there is some comparability ofthe results between species (monkey versus swine). Based on the findings reported entitled. Relative Bioavailability of Arsenic from Soil (August 2009) and the risk assessment process employed by the Superfund program, using 80 ppm as the cleanup level for arsenic is will be protective of human health.

Response to Second Comment: EPA's decisions are based on the database developed for the Site.

Response to Third Comment: As stated earlier, the surface water/sediment data indicates that very little to no contamination is migrating tlirough surface run-off following a rain event and based on the recent soil sampling effort the Agency conducted, very little contamination was migrated vertically in the soil. EPA collected a surface soil sample (0-6 inches) and a subsurface soil sample (12-18 inches below surface) at 939 locations. All samples were analyzed for organic pesticides and arsenic and lead. Only at 16 locations did any ofthe concentrations for the contaminants of concern exceeded their cleanup level in the subsurface soil sample.

explanation of significant difference to the remedial

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