SFUND RECORDS CTR 2141506
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION IX 75 Hawthorne Street San Francisco, CA 94105
MEMORANDUM
DATE: March 10,2008
SUBJECT: Request for a Time-Critical Removal Action for Residences most affected by the Asarco Hayden Plant Site, Hayden and Winkelman, Gila County, Arizona
FROM: Martin Powell, On-Scene Coordinator Emergency Response Section (SFD-9-2)
THROUGH: Steve Calanog, Acting Chief ^> Emergency Response Section (SFD-9-2)
TO: Daniel Meer, Chief Response, Planning & Assessment Branch (SFD-9)
I. PURPOSE
The purpose of this Action Memorandum is to obtain approval to spend up to $1,440,000 in direct costs to mitigate threats to human health, welfare, and the environment posed by the presence of high concentrations of arsenic, copper, and lead in residential soils in the Towns of Hayden and Winkelman, Gila County, Arizona. This Action will address those yards with concentrations of arsenic, copper, and lead in excess of Removal Action Objectives (RAOs) which are explained below.
The Action Memorandum would serve as approval for the expenditure required for U.S. EPA to take actions described herein to abate imminent and substantial endangerment to residents of properties contaminated by hazardous substances. The proposed removal of hazardous substances would be undertaken pursuant to Section 104(a)(1) of the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA), 42 U.S.C. § 9604(a)(1), and Section 300.415 of the National Oil and Hazardous Substances Pollution Contingency Plan (NCP), 40 CFR § 300.415.
II. SITE CONDITIONS AND BACKGROUND
Site Status: Non-NPL Category of Removal: Time-Critical CERCLIS ID: AZD008397127 SITE ID: 09JS A. Site Description
1. Physical Location
ASARCO, LLC owns and operates a set of facilities known as the Asarco Hayden Plant Site, which includes a crusher, a concentrator, an overhead conveyor, an active smelter, an inactive smelter, property with tailings piles, and other nearby properties in Hayden and Winkelman, Arizona. The facilities surround the town of Hayden, with a population of 900, and they are on two sides of the town of Winkelman, with a population of 450. Kearny, Arizona, with a population of approximately 2,250, is approximately 9 miles northwest of the facility. Hayden is located near the intersection of Highway 177 and Route 77, approximately 100 miles southeast of Phoenix and 52 miles northeast of Tucson. Winkelman is located approximately one mile southeast of Hayden. Releases from the Asarco facilities have caused hazardous substances, including arsenic, copper, and lead, to come to be located within the residential portions of Hayden and Winkelman. This Removal Action addresses contamination in the soil of the 15 residential properties in Hayden and Winkelman which have been shown to have the highest concentrations of these hazardous substances (the Removal Site).
2. Site characteristics
Removal Site consists of fifteen residential properties within Hayden and Winkelman. The residences are listed below:
Summary of Hayden Winkelman Removal Residential Locations
Parcel ID Address 101-07-035AS 71 0& 71 4 North Drive 101-07-040 767 Hayden Avenue 101-07-066 577 Utah Avenue 101-07-089Q 7 Warner Drive 101-07-089S Warner Drive 101-07-089T Warner Drive 101-07-091 765 Cottonwood Road 101-09-004 186 4th Street 101-09-036 1 74 2nd Street 101-09-039 1 63 1 st Street 101-09-070 589 Garfield Avenue 101-09-077 548 Velasco Avenue 101-09-088 455 Terrace Drive 101-09-140 562 Hillcrest Avenue 101-12-149 2nd Street (Hwy 177) The Asarco Hayden Plant Site in Hayden, Arizona, is an active copper ore processing, concentrating, and smelter facility located in Gila County, near the confluence of the Gila River and San Pedro River. The active portion of the Asarco Plant consists of Asarco's crusher, concentrator, smelter, and tailings impoundments areas. The crusher is located on the north side of State Route 177 and provides primary crushing of ore arriving via the Copper Basin Railway from the Ray Mine (and historically from other sources). An overhead conveyor (No. 9 conveyor), approximately 2,000 feet long, has an overhead portion (about 400 feet in length) that passes over some of Hayden's residential streets and directs ore from the crusher to the mill building at the concentrator facility. The 27,400 ton/day concentrator facility includes milling operations and two thickener tanks.
The 720,000 ton/year smelter facility is located approximately 2,000 feet east- northeast of Hayden and includes an oxygen flash furnace, converters, anode casting, oxygen plant, and acid plant (Asarco website, www.asarco.com, 2006). Although closely related, Asarco manages the concentrator and smelter operations separately, with each operation having a separate entrance. The active smelter is approximately 11 stories tall and treated air emissions are released to the atmosphere through a 1,000 foot tall stack. Slag from active smelter operations is deposited in an open dump area located immediately southeast of the smelter.
The former Kennecott smelter area, located on the north edge of Hayden and north of the concentrator facility, underwent demolition work beginning in 2004. It currently consists of miscellaneous building debris, storage tanks, foundations, and an abandoned slag dump northwest of the former smelter. The former Kennecott smelter stack was not subject to the demolition activity.
Tailings Impoundment AB/BC is located south of State Route 177 and north of the Gila River, extends for a length of approximately two and one-half miles, and has a maximum width of one mile and a maximum height of 200 feet. The newer Tailings Impoundment D is located south of the Gila River, extends for a length of approximately two miles, has a maximum width of 1,500 feet, and a maximum height of 150 feet.
Process/storm water management facilities consist of several small surface water impoundments located throughout the concentrator and smelter areas: Power House Wash (bisecting the active smelter area and concentrator/Hayden residential areas), retention ponds located south-southeast of Tailings Impoundment AB/BC, a large retention pond (Last Chance Basin) at the northwest edge of Tailings Impoundment AB/BC, and containment berms in selected areas of the tailings impoundments areas.
Hayden's drinking water is supplied by a well field, which is operated by Asarco and is located south of Hayden and east of Tailings Impoundment AB/BC. Winkelman's drinking water is supplied by three wells, which are operated by the Arizona Water Company, located east of town within the community park adjacent to the Gila River.
3. Removal site evaluation
In 2004, the EPA Emergency Response Section (ERS) under the authority of CERCLA, contracted Ecology & Environment Inc. to perform additional sampling in the Hayden area. Specific details of the scope of work, results, and conclusions from the removal assessment (RA) are provided in the ASARCO Hayden Removal Assessment: Final Report (Ecology & Environment, Inc., 2004). The objective of the RA was to continue to identify and address levels of metals contaminants contained in soil resulting from operations at the Asarco Hayden Plant Site, and specifically to evaluate impacts on the communities of Kearny, Hayden, and Winkelman. The investigation was focused on determining levels of metals contamination within residential, commercial, and public areas of the three towns. The summary in the following paragraphs focuses on the approach and results of sampling in Hayden and Winkelman. Soil samples were collected at a total of 51 locations in Hayden and 69 locations in Winkelman from randomly selected locations within an established grid. Background samples were collected at six locations along State Route 77 south of Winkelman. Surficial samples were collected to depths of approximately two inches below ground surface (bgs).
Of the 51 samples in the Hayden area, the total metals analyses revealed metals contamination above the Residential Soil Remedial Levels (R-SRL) at 40 locations including the following:
• Arsenic levels exceeded the R-SRL of 10 mg/kg at 40 locations (maximum of 91 mg/kg); • Copper levels exceeded the R-SRL of 2,800 mg/kg at 29 locations (maximum of 11,400 mg/kg); and • Lead levels exceeded the R-SRL of 400 mg/kg at one location (463 mg/kg).
Sample locations revealing elevated copper and lead concentrations generally coincided with locations showing high arsenic concentrations, with the highest concentrations typically concentrated close to Asarco facilities, including particularly the No. 9 conveyor belt.
Of the 69 samples from the Winkelman area, the total metals analyses revealed the following exceedances of R-SRLs: • Arsenic levels exceeded the R-SRL of 10 mg/kg at 16 locations (maximum of 320 mg/kg); • Copper levels exceeded the R-SRL of 2,800 mg/kg at seven locations (maximum of 19,000 mg/kg); and • Lead levels exceeded the R-SRL of 400 mg/kg at three locations (maximum of 485 mg/kg). The RA concluded that surficial soil contamination is present in the towns of Hayden and Winkelman, and that a soil sampling effort focused on residential yards is warranted as part of a Remedial Investigation (Rl).
As part of the Rl, residential soil sampling activities were conducted and included the collection of soil samples from 130 habitable homes within Hayden and Winkelman. This total consisted of 99 homes in Hayden and 31 homes in Winkelman. The residential soil sampling activities were conducted between January 30, 2006 and February 24, 2006.
Sample locations were selected within the town limits of Hayden and Winkelman based on the potential human risk of exposure to metals. To aid with this process, Hayden and Winkelman were divided into 26 separate zones. These zones were then separated into two categories termed Category 1 and Category 2. Category 1 includes areas in closer proximity to facility operations, which have a greater potential to be affected by aerial deposition, surface water runoff, or waste disposal activities, while Category 2 includes areas more distant from facility operations, which are likely to be affected primarily by aerial deposition. At least 30 percent of all residential lots in zones from Category 1 were sampled, while a lower sample frequency of at least 15 percent was employed for zones from Category 2.
Prior to sampling, a signed access agreement was obtained from the property owner or tenant at each residence. Ten surface samples were collected on each residential lot, which consisted of nine surface soil samples (0-2 inches bgs) and one subsurface sample (10-12 inches bgs).
Data collected from the surficial soil sampling at Hayden and Winkelman residential properties indicates that the primary metals of concern are arsenic, copper, and lead. Based on the laboratory results of the 99 homes sampled in Hayden, 97 homes had arsenic concentrations that exceeded the R-SRL of 10 mg/kg, 89 homes had copper concentrations that exceeded the R-SRL of 3,100 mg/kg, and 45 homes had lead concentrations that exceeded the R-SRL of 400 mg/kg. Of the 32 homes sampled in Winkelman, two residences had arsenic concentrations that exceeded the R-SRL (no homes showed exceedances of copper or lead). A small number of residential properties showed exceedances of R-SRLs for other metals, but none of these metals are widespread at elevated concentrations. In general, the highest concentrations of metals in soils were found in residential properties located closest to the active concentrator facility and the inactive former Kennecott smelter.
4. Release or threatened release into the environment of a hazardous substance, or pollutant or contaminant
Elevated levels of arsenic, lead and copper in the soil on and around private residences in the vicinity of the Asarco Hayden Plant constitute a release of hazardous substances to the environment. A review of Rl residential soil sampling data by an EPA Region 9 toxicologist has identified levels of metals in residential yards that raise concerns. While EPA is considering a broader removal action, this initial Removal Action is intended to immediately address those yards that have the highest levels of contamination. The RAOs for this Removal Action have been selected as:
• Arsenic - 200 mg/kg • Lead - 2000 mg/kg • Copper - 20,000 mg/kg
The sample data for each residential property sampled during the Rl was compared to the site RAOs. Based on this comparison, 14 properties in Hayden and 1 in Winkelman have been identified as having levels of metals in soil exceeding the RAOs, and are targeted for inclusion in this Removal Action. This data is summarized in the table below:
Summary of Residential UCL Soil Data1 Arsenic Lead Copper 95% 95% 95% Parcel ID Address Town Zone UCL UCL UCL 710 & 714 North 101-07-035AS Drive Hayden 10 27.9 204 25,100 101-07-040 767 Hayden Avenue Hayden 9 54.5 217 23,400 101-07-066 577 Utah Avenue Hayden 11 12.2 3,180 3,310 101-07-089Q 7 Warner Drive Hayden 9 37.7 156 22,100 101-07-0893 Warner Drive Hayden 9 66.5 230 20,600 101-07-089T Warner Drive Hayden 9 540 265 19,500 765 Cottonwood 101-07-091 Road Hayden 8 45 250 22,300 101-09-004 186 4th Street Hayden 12 37 8,170 7,320 101-09-036 174 2nd Street Hayden 14 32.1 2,330 7,000 101-09-039 163 1st Street Hayden 14 22.3 3,010 6,890 101-09-070 589 Garfield Avenue Hayden 13 25.9 3,030 8,510 101-09-077 548 Velasco Avenue Hayden 14 45.7 7,250 6,550 101-09-088 455 Terrace Drive Hayden 15 19.1 92,600 2,690 101-09-140 562 Hillcrest Avenue Hayden 16 221 779 39,700 101-12-149 2nd Street (Hwy 177) Winkelman 21 45.3 2,330 5,130 Site RAO(s) 200 2,000 20,000 All units are in mg/kg. The "UCL" is the Upper Confidence Limit. 5. NPL status
The Asarco Hayden Plant Site is not on the National Priorities List (NPL). In 2002, EPA conducted a RA and a subsequent Rl in 2006-2007 at the Asarco Hayden Plant Site (CERCLIS ID No. AZD008397127) and surrounding communities. The two site reports are included in the Administrative Record. The RA and Rl reports identified observed contamination and observed releases of hazardous substances at the Asarco Hayden Plant Site.
B. Other Actions to Date
No other response actions have occurred at the Asarco Hayden Plant Site to date.
C. State and Local Authorities' Roles
1. State and local actions to date
The ADEQ Remedial Projects Section, PA/SI Section and Voluntary Cleanup Program have participated during the course of the RA, Rl, and Removal Action planning activities. EPA and ADEQ have reached consensus that EPA will take the lead on removal activities pertaining to the Removal Site.
III. THREATS TO PUBLIC HEALTH OR WELFARE OR THE ENVIRONMENT, AND STATUTORY AND REGULATORY AUTHORITIES
Current conditions at the Removal Site pose the threat of potential future releases of hazardous substances, namely arsenic, lead and copper. The likelihood of direct human exposure, via ingestion and/or inhalation of hazardous substances, and the threat of potential future releases and migration of those substances, pose an imminent and substantial endangerment to public health, and/or welfare, or the environment based on the factors set forth in the NCP, 40 CFR § 300.415(b)(2). These factors include:
1. Actual or potential exposure to hazardous substances or pollutants or contaminants to nearby populations
As described in Section II.A.4, high concentrations of arsenic, lead and copper have been detected in samples of residential soils at the Removal Site. Arsenic, lead and copper may be entrained in naturally and mechanically generated dust and/or transported on shoes and clothing of residents passing over contaminated areas. Gardening, yard work and recreation may result in exposure to contamination. Arsenic primarily enters the body through ingestion or inhalation as airborne dust. Arsenic and arsenic compounds are considered skin and lung carcinogens in humans and high levels of ingested arsenic are known to produce death. Ingestion of arsenic could also cause irritation of stomach and intestines, nerve injury, and possible liver damage. Common side effects include decreased production of red and white blood cells, abnormal heart rhythm, impaired nerve function such as feeling pins and needles sensation in hands. Studies in animals indicate that doses of arsenic sufficient to impact pregnant females also cause low birth weight, fetal malformations, or death. Oral ingested causes skin pattern changes such as warts, moles, and corns that may develop into skin cancer. Inhalation of arsenic dust may cause irritated lungs but more significantly increased lung cancer has been associated with the exposure.
Exposure to lead is particularly dangerous to unborn and young children. Lead can affect virtually every system in the body and is particularly harmful to the developing brain and nervous system of fetuses and young children. Unborn children can be exposed to lead through their mothers' circulatory systems, which exposure may cause premature births, smaller babies, and decreased mental ability in the infant. Severe lead exposures in children can cause coma, convulsions, and even death. Lower levels of lead exposure can cause adverse effects on the central nervous system, kidney, and hematopoietic system. Blood lead levels as low as 10 milligrams per deciliter (ug/dL), which would not cause distinctive symptoms, are associated with decreased intelligence and impaired neurobehavioral development. Many other effects begin at low levels including decreased stature or growth, decreased hearing acuity, and decreased ability to maintain a steady posture.
In adults, lead exposure may decrease reaction time and possibly affect the memory. Lead exposure may also cause weakness in fingers, wrists, or ankles. Finally, lead exposure may cause high blood pressure, anemia, brain and kidney damage, miscarriages, and damage to the male reproductive system.
Copper at low levels is essential for good health. However, exposure to higher doses can be harmful. Long term exposure to copper dust can irritate the nose, mouth, and eyes, and cause headaches, dizziness, nausea, and diarrhea. Ingestion of higher than normal levels of copper, may cause nausea, vomiting, stomach cramps, or diarrhea. Intentionally high intakes of copper can cause liver and kidney damage and even death.
Contamination is readily accessible to on-site full-time residents and potentially nearby part-time and/or full-time residents. Persons living on these contaminated properties, or engaging in recreational activities on or in close proximity to the properties are likely to come into contact with uncontrolled hazardous substances present within residential soils.
2. Weather conditions that may cause hazardous substances or pollutants or contaminants to migrate or be released Heavy rains and winds may transport contaminated soils from the Removal Site, causing contaminant dispersal and increasing the likelihood of exposure.
3. Availability of other appropriate Federal or State response mechanisms to respond to the release
The Removal Site is located on private land and is therefore not under the jurisdiction of any other Federal agency. EPA and ADEQ are working in conjunction to obtain an administrative order on consent for a broader removal action and a complete Remedial Investigation.
IV. ENDANGERMENT DETERMINATION
Actual and threatened releases of hazardous substances from the Removal Site, if not addressed by implementing a Time-Critical Removal Action may continue to present an imminent and substantial endangerment to public health, or welfare, or the environment.
V. PROPOSED ACTIONS AND ESTIMATED COSTS
A. Proposed Actions
1. Proposed action description
All of the actions to be taken during this removal will comply with all applicable, relevant, or appropriate requirements (ARARs) to the extent practicable, considering the exigencies of the situation, and provide an effective mitigation of the imminent and substantial threats posed to the general public health and environment by the Removal Site.
USEPA proposes to mitigate imminent and substantial threats to human health, welfare, or the environment by taking the following actions to prevent direct human contact with the identified contaminants in residential soils.
• Obtain consensual access agreements from the property owners.
• Document existing physical conditions of each property, and develop restoration plans.
• Excavate soil at the 15 most highly contaminated of the previously sampled properties, specifically, the 14 yards in Hayden and 1 yard in Winkelman that exceed 95% UCL soil concentrations of 200 ppm Arsenic, 2000 ppm Lead, or 20,000 ppm Copper. Soil removal at each property will be to background or SRLs, or to a maximum depth of 24 inches, at the discretion of the OSC.
• Conduct confirmatory sampling and analysis. Transport and dispose of excavated soil.
Clean interior of residences as deemed necessary by the On Scene Coordinator (OSC).
Provide for temporary relocation of residents as deemed necessary by the On Scene Coordinator (OSC).
Conduct air monitoring during the removal activity.
Restore properties to pre-removal condition per the developed restoration plans. Replacement soil will meet background levels or SRLs for all constituents, at the discretion of the OSC.
2. Contribution to remedial performance
The selected response contributes to any additional conceivable future remedial action by preventing direct human contact with the contaminated soil at the most contaminated yards. This will eliminate the direct contact pathway to hazardous substances found in the Removal Site's surface and subsurface soils.
3. Description of alternative technologies
The proposed technology eliminates human contact with surface soils at the Removal Site efficiently and effectively. No other cost effective alternatives exist.
4. Applicable or relevant and appropriate requirements (ARARs)
Section 300.415(j) of the NCP provides that removal actions must attain ARARs to the extent practicable, considering the exigencies of the situation.
Section 300.5 of the NCP defines applicable requirements as cleanup standards, standards of control, and other substantive environmental protection requirements, criteria or limitations promulgated under Federal environmental or State environmental or facility siting laws that specifically address a hazardous substance, pollutant, contaminant, remedial action, location or other circumstances at a CERCLA site.
Section 300.5 of the NCP defines relevant and appropriate requirements as cleanup standards, standards of control and other substantive requirements, criteria, or limitations promulgated under Federal environmental or State environmental or facility siting laws that, while not applicable to a hazardous substance, pollutant, or contaminant, remedial action, location, or other circumstances at a CERCLA site, address problems or situations sufficiently similar to those encountered at the CERCLA site and are well-suited to the particular site.
Because CERCLA on-site response actions do not require permitting, only 10 substantive requirements are considered as possible ARARs. Administrative requirements such as approval of, or consultation with administrative bodies, issuance of permits, documentation, reporting, record keeping, and enforcement are not ARARs for the CERCLA actions confined to a site.
The following ARARs have been identified for the proposed response action. All can be attained.
Federal ARARs: The CERCLA Off-Site Disposal Rule OSWER Directive 9347.3- 8FS; and the U.S. Department of Transportation of Hazardous Materials Regulations 49 CFR Part 171, 172 and 173.
State ARARs: USEPA has considered the SRLs in the selection of a cleanup level as stated above.
5. Project schedule
It is estimated that removal activities will take approximately 6 months to complete.
B. Estimated Costs
Regional Removal Allowance Costs
Cleanup Contractor $ 900,000 (This cost category includes estimates for: ERRS, subcontractors, Notices to Proceed, and Interagency Agreements with Other Federal Agencies.)
Other Extramural Costs Not Funded from the Regional Allowance
START Contractor $ 300.000
Extramural Subtotal $ 1,200,000
Extramural Contingency (20%) $ 240.000
TOTAL, Removal Action Project Ceiling $ 1,440,000
VI. EXPECTED CHANGE IN THE SITUATION SHOULD ACTION BE DELAYED OR NOT TAKEN
Should the action described in this action memorandum be delayed or not taken, the potential exposure of nearby human populations to hazardous substances found in the surface and subsurface soils will remain unabated.
11 VII. OUTSTANDING POLICY ISSUES
There are no outstanding policy issues with the Removal Site identified at this time.
VIII. ENFORCEMENT
Please see the attached Confidential Enforcement Addendum for a discussion regarding potentially responsible parties.
IX. U.S. EPA RECOMMENDATION
This decision document represents the selected removal action for the Removal Site, Hayden and Winkelman, Gila County, Arizona developed in accordance with CERCLA as amended, and not inconsistent with the NCR. This decision is based on the Administrative Record for the Removal Site.
Because conditions at the Removal Site meet the NCR criteria for a Time-Critical Removal Action, USEPA enforcement staff recommend the approval of the removal action proposed in this Action Memorandum. The total project ceiling if approved will be $1,440,000, of which an estimated $900,000 comes from the Regional Removal Allowance. Approval may be indicated by signing below.
Approve: Daniel Meer, CRIef Date Response, Planning and Assessment Branch
Disapprove: Daniel Meer, Chief Date Response, Planning and Assessment Branch
Enforcement Addendum
12 INDEX TO THE ADMINISTRATIVE RECORD
1. ASARCO Hayden Removal Assessment, December 2004 .
2. Remedial Investigation Work Plan, September 2005
3. Remedial Investigation Field Sampling Plan, November 2005
4. Remedial Investigation Residential Soil Sampling Results, 2007
5. ASARCO website, www.asarco.com