Contents Chapter 2
Acronyms The Oak Ridge Environmental Management Program has four primary components. Environmental restoration studies environmental contamination and proposes cleanup solutions. Decontamination and decommissioning removes bulk contaminants and contaminated equipment from process buildings no longer in use. Waste management treats, stores, and disposes of waste generated from Department of Energy operations and cleanup work. Technology development creates new technologies or modifies existing technologies to solve environmental problems. Public involvement in decision-making is also an integral part of the Environmental Management Program.
For nearly half a century, one of the primary missions of DOE and its predecessor agencies was the production of nuclear weapons for the nation's defense. Production of materials for nuclear weapons, which began on the ORR in 1943, as part of the secret World War II Manhattan Project, also produced radioactive and hazardous wastes. In 1989 the reservation was placed on EPA's National Priorities List (NPL), which names waste sites across the country most in need of cleanup.
Once the reservation was added to the NPL, cleanup became subject to the process specified in CERCLA, more commonly known as Superfund. This law requires federal agencies and private-sector companies to investigate and remedy abandoned or uncontrolled hazardous waste sites where a release has occurred or may occur. It also requires public involvement to ensure that citizens are informed of and are involved in making cleanup decisions.
In 1990 DOE-HQ established the Office of Environmental Management, making DOE-ORO responsible for cleanup of the reservation, with Energy Systems serving as its managing and operating contractor. The following sections highlight some of the environmental management projects that were addressed in 1995.
3.2.1 K-25 Powerhouse Implosion
On September 9, 1995, the K-25 Powerhouse was demolished.
Explosives were used to implode the steel structure after most of the
brick and masonry walls had been removed. The facility was built in 1945
in support of the Manhattan Project and later was used for offices,
laboratories, and storage. The Powerhouse demolition was part of
DOE's Environmental
Restoration Incentive Project program, a new contracting method that
promotes faster, more cost-effective cleanups without compromising
safety (Fig. 3.1). The scope of this project included decontamination and demolition of
14 of the 22 structures located in the Powerhouse area.
3.2.2 A Decision Is Reached for Lower Watts Bar Reservoir
In 1995 DOE completed an environmental investigation of Lower Watts Bar
Reservoir downstream from Kingston (Fig. 3.2). Copies of DOE's findings were made available to the public, and
stakeholders meetings were held in Oak Ridge, Kingston, and Spring City.
The public had the opportunity to comment on the DOE findings between
March 24 and April 28, 1995. Results of the survey showed that
risks from contaminants in the reservoir are very low. Therefore, DOE
recommended that no action be taken to remove the contaminants.
Polychlorinated biphenyls (PCBs) and radioactive cesium are the contaminants of greatest concern in the reservoir. PCBs are cancer-causing industrial chemicals that accumulate in the flesh of fish. Their presence in Lower Watts Bar Reservoir can be attributed in part to DOE activities, although their use was once widespread, and they are also found in waters upstream of the ORR. Most of the cesium contamination resulted from DOE activities that took place 40 years ago. Small but detectable amounts are buried in deep-water sediment of the reservoir.
DOE and its regulators (EPA and TDEC ) have signed the Lower Watts Bar Reservoir Record of Decision (ROD). The ROD includes comments received during the public comment period and calls for institutional controls, such as fishing advisories and control of dredging activities, to limit exposure to contaminants in fish and sediments. DOE will continue monitoring conditions in the reservoir for at least another 5 years, at which time DOE, EPA, and TDEC will determine whether further monitoring is needed.
3.2.3 DOE Submits Record of Decision for Remediation of Lower East Fork Poplar Creek
On June 1, 1995, DOE delivered its ROD for Lower East Fork Poplar
Creek to EPA and TDEC for approval. DOE also held a public meeting on
June 8 to explain the ROD to the public. The ROD documents DOE's
plan for the removal of mercury contamination from floodplain soil along
the creek (Fig. 3.3). The contamination was released inadvertently into the creek from the
Y-12 Plant during the
1950s, where for many years mercury was used in production processes.
The planned remediation involves removal of contaminated soil until the level of mercury (measured in parts per million) is reduced and is no longer a threat to human health. To determine a safe level, DOE considered the types of mercury compounds present as well as the quantity. The threat posed by mercury to human health, and the health of other organisms, depends on how readily the mercury is taken into the body; some forms of mercury, such the elemental metal and mercuric sulfide, are less easily absorbed than mercuric chloride. By identifying the amounts and types of mercury present, DOE was able to determine a ``percent bioavailablity factor,'' from which it could estimate a safe parts-per-million concentration for the Lower East Fork Poplar Creek floodplain soil. Its findings were corroborated by EPA, TDEC, and the Agency for Toxic Substances and Disease Registry (ATSDR), which is part of the Centers for Disease Control.
DOE's planning was also tempered by public opinion. On January 26, 1995, DOE held a public meeting to announce a proposed plan for removal of the mercury. The plan was the result of a remedial investigation that had begun in 1990. DOE received 90 responses from the public, 50 at the meeting and 40 more during the comment period, which lasted until February 22. It was the most responses ever generated from a proposed remedial action in Oak Ridge. Many of the comments expressed concerns that the proposed excavations would harm the floodplain ecology, which in spite of the mercury, is thriving. Following the announcement of a revised cleanup level, DOE held another comment period, from June 14 to July 14.
Actions to be taken include the removal of all floodplain soil containing mercury concentrations above 400 ppm, thus reducing the threat to human health while minimizing the impact on the local ecology. The creek will continue to be monitored to determine the effectiveness of the project. The soil will be taken to a permitted landfill on the Y-12 Plant, and the excavated sites will be back-filled with clean soil. At a cost of about $30 million, the project will allow unrestricted future land use. All documentation, including public comments and the ATSDR report, pertaining to the Lower East Fork Poplar Creek Floodplain remediation project are available at the DOE Information Resource Center, 105 Broadway Avenue, Oak Ridge.
3.3 DECONTAMINATION AND DECOMMISSIONING
3.3.1 Variable Dose Rate Irradiation Facility Dismantled
The Variable Dose Rate Irradiation Facility
(VDRIF), located on the
ORR, has been dismantled.
During the 1960s and 1970s, VDRIF had served as state-of-the-art
radiation-exposure research facility. It contributed significantly to
experiments in radiobotany, pathology, soil chemistry and plant
nutrition, genetics, and animal physiology. In 1995 its cobalt-60
sources were removed, thus ending the long useful service of VDRIF.
Research into the effects of radioactive fallout began in Oak Ridge in 1948, following the weapons testing at Alamogordo, New Mexico. The Atomic Energy Commission set aside a portion of the ORR as an agricultural research station to be operated jointly with the University of Tennessee. Its purpose was to study responses of plants and animals to external radiation, uses of radioisotopes in agricultural research, and transport of radionuclides in food chains. During the 1950s the open-air Low Dose Irradiation Facility was constructed to study the effects of whole-body gamma radiation on large animals.
The desire to conduct experiments at higher dose rates led to the building of VDRIF. Funding for construction was authorized by the Atomic Energy Commission (AEC). ORNL, the Y-12 Plant, and the University of Tennessee collaborated to supply the design and materials.
The VDRIF is an enclosed structure containing an entrance maze, a control room, and an irradiation room. Each of the six cobalt-60 radiation sources contained 363 1-cm-diam. wafers within stainless steel, lead-shielded tubes. The activity of the wafers increased exponentially from top to bottom to provide variable dose rates, and each source could be raised or lowered independently of the others from shielded wells. In June 1967 the activity of each source, 452 Tbq (4.52E\math{+}14 Bq or 1.2E\math{+}16 pCi) contributed to an initial maximum exposure of about 70 R/min at the exposure stations.
The Agricultural Research Laboratory (renamed the ``Comparative Animal Research Laboratory'' in 1975) became the responsibility of ORAU in 1981. The VDRIF sources were last used in May 1984; the sources were sealed and the lifting mechanisms were removed in 1991. In 1995 a company under contract to ORAU on behalf of DOE transported the sources to California for recycling. The VDRIF structure is currently vacant and is available for other uses.
3.4.1 TDEC Issues an Order for Mixed-Waste Treatment and Storage
In September 1995 the commissioner of
TDEC issued an order to
DOE that specifies a schedule
for the treatment and disposal of mixed waste originating from the three
ORR sites. In early
April 1995 DOE submitted to TDEC a proposed treatment plan for all
mixed wastes on the ORR. The development of the plan encouraged
stakeholder involvement, which in addition to general stakeholder
meetings included three workshops for local individuals interested in
waste treatment. The state order modifies the proposed site treatment
plan.
Mixed waste is a mixture of hazardous chemical waste and transuranic radioactive waste components. DOE was required to submit a mixed-waste treatment plan under RCRA as amended by the Federal Facilities Compliance Act of 1992. The Act requires that hazardous components of mixed waste be treated before disposal.
The final order details a timetable for treatment of the wastes, includes schedules for additional characterization of some wastes when it is required to support planning for treatment, and takes into account funding availability. It will be reviewed annually to consider changing technologies and funding levels. The order is available in the DOE Public Reading Room at 55 Jefferson Circle, off the turnpike in Oak Ridge.
3.4.2 Envirocare Shipments Continue
Shipments are continuing from the K-25 Site to Envirocare of Utah,
Inc. Since August of 1994 more than 20,592 drums (264 box
cars) have been shipped to the Envirocare facility, located
80 miles (about 129 km) west of Salt Lake City. Wastes shipped
from the K-25 Site include material dredged from two ponds as well
as ash from the TSCA
Incinerator.
Envirocare is the only commercial facility in the United States licensed to dispose of mixed waste once it has been treated to stabilize the hazardous components. After the box cars arrive at Envirocare, the drums are unloaded, are tested to ensure that they meet waste acceptance criteria, and are placed in a lined disposal cell. When the cell is filled, steel box lids are placed around the drums, forming a boundary (Fig. 3.4). Clean concrete is then poured over the drums to fill void spaces between them. Once filled completely, the cell is capped with clean soil.
3.5.1 TRANSCOM Tracks Waste Shipments
The U.S. Transportation Command
(TRANSCOM) is part of
DOE's Transportation
Information Network, which uses a satellite positioning and reporting
system to track highway shipments of waste and spent nuclear fuel. After
vehicle information is transmitted to a satellite receiving station, it
is relayed to the TRANSCOM Control Center in Oak Ridge, located at
3 Main Street. Authorized users can gain access to the information
from their personal computers.
3.5.2 Interim Waste Management Facility Refines Tumulus Disposal Technique
At the ORNL Interim Waste
Management Facility (IWMF)
DOE applies ``tumulus'' disposal technology to ensure that
LLW stays isolated from the
environment. Developed by the French nuclear industry, tumulus disposal
involves placing compacted LLW in metal boxes, sealing the boxes, and
placing them inside concrete vaults. The vaults are stacked three-high
on an engineered concrete pad that has been reinforced with layers of
sand and gravel and with plastic and fabric liners. Impervious liners
and soil are placed over completed stacks, making an earthen mound that
resembles the ancient burial sites from which the technique gets its
name.
Tumulus disposal began at ORNL in 1988, when two pads were installed at SWSA 6. The first two pads were used until 1992; they are currently sealed and covered. The first IWMF pad was built in 1991. The design was modified, based on experience with the first two tumuli. The primary modification was the inclusion of a surface-water collection and monitoring system. Each pad has a drainage system beneath it to direct surface water to a monitoring station, where the water is either held for treatment or released if it meets discharge requirements.
Currently, two pads are full, a third is operational, and three others are being built. Each measures 50 by 90 ft (15.25 by 27.45 m) and is capable of holding about 330 vaults. Contents are limited to contact-handled LLW (Fig. 3.5).
Several major environmental cleanup decisions were reached in 1995 with stakeholders playing key roles. DOE's public involvement program continued to hold regular stakeholder meetings in which citizens were updated on environmental management work on the reservation. DOE also hosted numerous other workshops and public meetings (Fig. 3.6). In addition, the Oak Ridge Reservation Environmental Management Site-Specific Advisory Board was formed and began operation in late 1995.
Other 1995 public-involvement activities include the following:
3.6.1 EnvironMENTAL Fair 1995
DOE held its fourth annual EnvironMENTAL Fair on October 10. More
than 2000 sixth-graders from 27 area schools had fun while learning
what we can all do to make the world a cleaner place (Fig. 3.7).
3.6.2 Common Ground Process Concludes
A process that began in 1994 to involve all affected stakeholders in
land-use planning at the ORR
concluded in late 1995. More than 350 stakeholders participated in the
Common Ground Process, including citizens who live and work in the
surrounding region, local government leaders, union leaders, opinion
leaders, regulators, and senior management from DOE and
Energy Systems.
Conclusions reached in the final Common Ground report will be used to aid in reaching cleanup decisions and in strategic planning for overall land use. The overall vision specifies that the site should serve as an integrated science, education, and technology complex operated in partnership with the private sector. Under this scenario, the reservation would be managed by the federal government as a single parcel. The final report also recommends a comprehensive planning process, led by a group of federal, state, and local interests, to work through land-use decisions.
3.6.3 Site-Specific Advisory Board Convenes
In September 1995 the Oak Ridge Environmental Management
Site-Specific Advisory Board held its first meeting. The board was
established to advise DOE on environmental management issues, including
recommendations for cleanup levels, technology development, and
long-term waste management issues. The group includes 17 citizen
members from communities affected by cleanup decisions and three
nonvoting members from DOE,
TDEC, and
EPA Region 4. The board
co-hosted with DOE two workshops on DOE 's Prioritization List for
Fiscal Year 1998.
3.6.4 Some Web Sites and a New Toll-Free Number
You can get the latest information on environmental cleanup and waste
management in Oak Ridge, including the Public Involvement Calendar, at
the following web addresses:
Stakeholders outside the local calling area may reach the Environmental Management Community Relations Office by calling toll-free: 1-800-382-6938.