ASARCO Incorporated (ASARCO) operated a lead refinery at 500 Douglas Street in Omaha, Nebraska, for over 100 years beginning in the 1870s. The operation of the refinery ceased in 1997. As a routine part of the refinery operation, lead particles were emitted into the atmosphere at the refinery.
In addition, the Gould Incorporated lead battery recycling plant was located at 555 Farnam Street in Omaha and was a secondary smelter of lead from discarded lead batteries. The blast furnace used to smelt the lead at the Gould plant emitted lead particles into the air from that refinery. The Gould plant closed in 1982.
Several other facilities in the Omaha area used lead in their manufacturing processes. A few of these included Carter White Lead at 21st and Locust Street which produced white lead paint bases and red lead and litharge protective coatings until 1936, Omaha Shot and Lead which later became Lawrence Shot and Lead, and then became National Lead Company which manufactured lead shot by melting pig lead, Grant Storage Battery Company, Storage Battery Factory, and Exide Corporation which manufactured lead storage batteries.
Numerous other locations in the Omaha area such as foundries, iron works, metal salvaging companies, and other manufacturers used or processed lead at their facilities.
In 1998 the Omaha City Council asked the U.S. Environmental Protection Agency (EPA)to look into why the Douglas County Health Department (DCHD) found children with elevated blood-lead concentrations more often in east Omaha than anywhere else in the county. The EPA began an investigation using its authority under the Superfund Law. Most of this investigation has involved the sampling of soil at residential homes.
Sampling of residential soil began in March of 1999 and is still on-going. Approximately 40% of those analyzed exceed the EPA’s 400 parts per million (ppm) screening level.
The EPA has plotted the early results of the Omaha metropolitan area on a map and had it analyzed to identify any geographic trends. This analysis did reveal a geographic trend that shows surface contamination which gradually decreases with increasing distance from the downtown area.
The EPA continues to test residential properties including the homes of elevated blood-lead children (EBL children) and homes where licenced child care services are being provided. The testing of these properties is given priority over other types of residential properties.
In 2003, the EPA expanded its residential soil sampling effort to further define the boundaries of contamination. The EPA began the 2003 expanded soil sampling effort in May and tested soil from approximately 13,000 residential properties, including child care facilities and EBL residences. The EPA resumed its sampling effort in the Spring of 2004 and plans to test the soil of 12,000 residences by the end of 2004.
The 2003 soil testing effort identified 574 residential properties with one or more non-foundation samples at, or above, 1200 ppm. These properties are eligible for EPA’s ongoing soil removal action. In addition approximately 10 homes of children with an elevated blood-level were found to have soil concentrations of 400 ppm or greater during the 2003 sampling effort.
Four additional licenced child care facilities were also found to have lead at or above 400 ppm. The EPA has also included these EBL homes and child care facilities in the soil removal action.
On March 31, 2005 an Action Memorandum Amendment was signed. The purpose of this amendment was to change the previously approved scope of work and to seek a funding ceiling increase for continued removal response at the Omaha Lead Site, which encompasses eastern Omaha, Nebraska. Two Action Memoranda have previously been approved for work at the Site. The first Action Memorandum was approved on August 2, 1999, and addressed lead-contaminated soils exceeding 400 parts per million (ppm) at child care facilities and residences where a child with an elevated blood-lead level (EBL) exceeding 15 micrograms per deciliter (µg/dl) lived. This Action Memorandum was amended on August 3, 2001, to lower the EBL threshold from 15 µg/dl to 10 µg/dl. The second Action Memorandum was approved on August 22, 2002, and addressed lead-contaminated soils at highly contaminated properties at the Site where one non-foundation sample exceeded 2,500 ppm. The second Action Memorandum was amended on March 25, 2004, to combine the activities of both Action Memoranda into a single response action and increase the funding and scope to include residential properties with lead-contaminated soil above 1,200 ppm. The purpose of the current Action Memorandum Amendment is to expand the scope of the removal action to include elements of an Interim Record of Decision (ROD) issued on December 15, 2004, for the Site, and to increase the expenditure ceiling to allow funding of these activities.
The removal action will allow continued removal response to address the highest priority lead-contaminated residential properties at the Site. This Action Memorandum Amendment enables several significant enhancements to the ongoing removal response action including:
• Lowering the action level from 1,200 ppm to 800 ppm for residential properties that are not otherwise eligible for response on the basis of high child-impact or EBL lead levels;
• Modifying the cleanup level to continue excavating until reaching a residual concentration of less than 400 ppm in the upper foot of soil, or less than 1,200 ppm at depths of one foot or greater. In garden areas, excavation will continue until reaching a residual concentration of 400 ppm in the upper two feet of soil, or less than 1,200 ppm at depths of two feet or greater. The installation of a physical barrier prior to backfilling will be discontinued;
• Expanding the types of properties that are considered high child-impact areas, and therefore eligible for response if non-foundation lead concentrations exceed 400 ppm, to include schools, churches, parks, vacant lots, and other properties where children could congregate;
• Providing for stabilization of deteriorating, exterior lead-based paint in cases where the continued protectiveness of the remedy would be threatened by loose and flaking paint; and
• Providing for high-efficiency cleaning of household interiors for remediated properties when interior dust concentrations exceed the allowable standards established by the United States Department of Housing and Urban Development (HUD), and the Environmental Protection Agency (EPA). These standards allow a maximum dust loading of 40 micrograms per cubic feet (µg/ft2) for floors and 250 µg/ft2 for window sills.
The EPA considers 400 ppm as a screening level for lead contamination in residential soils. Concentrations of lead exceeding 400 ppm have been found in one or more non-foundation samples at 8,967 residential properties at the Site. These include 92 licensed child-care centers and 287 EBL residences. More than 2,500 additional residential properties have been identified with at least one non-foundation sample exceeding 800 ppm that are eligible for a soil response under this Action Memorandum Amendment.
A new Interagency Agreement (IAG) with the U.S. Army Corps of Engineers was entered into on August 16, 2005, that provides for remediation of an additional 350 residential properties by Environmental Chemical Corporation. This IAG and the recent award of a performance-based contract by EPA to Environmental Restoration, provide for remediation of up to 650 additional properties during the current construction season. Yard cleanups are also continuing under the ERRS contract until a new time and materials contract can be negotiated with a small disadvantaged business [8(a)] that will replace this mechanism.
A cooperative agreement application was received from Omaha on August 29, 2005 that will provide for the City Lead Hazard Control Program to assume the lead for stabilization of deteriorating exterior paint and deep cleaning of interior dust. The City will leverage EPA funds with Department of Housing and Urban Development grant funding to address multiple lead exposure sources at affected properties.
Subcontractor staff for the EPA public information centers (PICs) in Omaha has been selected. Training will be provided to PIC staff the week of September 19, 2005, at the Regional Office. Initial PIC located in south Omaha will open following completion of training. Negotiations are continuing for north Omaha office space.
Negotiations with the primary potentially responsible party have been extended through September 30, 2005. To date, 1,553 properties have been characterized for lead in 2005, bringing the project total to 27,281 properties. A total of 501 properties have been excavated in 2005, bringing the project total to 1,208 properties as of September 2, 2005.
