Salting away nuclear waste

Southeastern New Mexico is a lot like the rest of the western United States. There are precious few acres of farmland, scattered communities on the horizon and a few breathtaking natural monuments.

Carlsbad Caverns National Park, which is an underground limestone formation with as many as 86 caves and the jewels of nature's forces inside, is the most prominent.

There is also a low-level radioactive waste repository that's now open and accepting tons of nuclear waste.

The U.S. Department of Energy (DOE) received its first shipment of low-level radioactive waste in March from the Los Alamos National Laboratory in northern New Mexico, and other shipments have arrived from the Idaho National Engineering and Environmental Laboratory (INEEL) and the Rocky Flats Engineering and Technology Site, located near Denver. The race is on to fill the Waste Isolation Pilot Plant (WIPP) to the brim with transuranic radioactive waste - tools, protective clothing and equipment used during the Cold War to manufacture and arm the U.S. nuclear arsenal.

The first storage area is now a third full, and officials are preparing for increased shipments of plutonium-contaminated waste.

The first shipment of waste arrived March 26, 1999, from Los Alamos National Laboratory (LANL) only after conforming to strict requirements, such as tight security and transportation of the waste only under optimum weather conditions. The waste reached its destination under the watchful eye of nuclear waste storage proponents and amid the rallying of opponents.

This milestone marks the attainment of DOE's goal of permanent disposal of defense-generated transuranic waste left from research activities and production of nuclear weapons. Transuranic waste consists of metal tools, rubber gloves, cloth lab coats, shoe covers, rags and other items contaminated during weapons production and laboratory operations.

"This shipment to WIPP represents the beginning of fulfilling the long overdue promise to all Americans to safely clean up the nation's Cold War legacy of nuclear waste and protect the generations to come," said DOE Secretary Bill Richardson.

To understand the immensity of WIPP, one almost has to take a tour of the site itself. Near the WIPP site are several salt-producing industries; however, none are mining salt to make room for transuranic waste, which is what is occurring at WIPP. Some 2,200 feet below the earth's surface, workers have dug an 8-mile series of tunnels that lead to containment rooms where the transuranic waste is disposed.

The 56 rooms vary in depth but are mostly 100 yards deep; they also are 13 feet high and 33 feet wide. Tons of waste can be stored in each room, and, once they are filled, the rooms will be sealed. The salt, however, becomes the final container for the waste. There are seven rooms in eight panels and each panel, or hallway, will be used as a disposal area.

The life of the WIPP project is projected to last 35 years.

Project opponents
Opponents of the WIPP site have been vocal and successful in stopping shipments of waste, at least until recently.

The Concerned Citizens for Nuclear Safety (CCNS), based in Santa Fe, argue that there is a 220-foot crack in the ceiling in Room 7, where the waste is currently being stored. Opponents also say that little if any monitoring is being conducted.

While it is true that a crack in the ceiling exists, that is typical of the movement of salt, according to WIPP's engineers at Westinghouse Electric Corp. It moves, or fractures, then heals itself.

"That's the reason the rooms are designed the way they are," said Donavan A. Mager, media coordinator at the WIPP site for Westinghouse. "Monitoring equipment is placed strategically throughout the salt bed and watched constantly. We also are using the latest mining technology."

Joni Arends, waste program director for CCNS, claims the roof in each of the rooms where the contaminated waste will be stored runs the risk of collapsing at any given time because the rooms were dug out more than a decade ago. However, Westinghouse officials say they have proof this will not occur, according to tests they conducted more than a decade ago. Westinghouse is also using a roof bolting system, along with wire mesh, to slow the movement of the salt, as the waste begins to fill each of the rooms.

CCNS officials want to keep nuclear waste collected after 1970 in monitored retrievable facilities, so that if there is a problem, it could be addressed, then restored. Additionally, they are asking officials to take a second look at a Manhattan II project for nuclear waste disposal. (Manhattan II is the international campaign for a comprehensive test ban treaty to completely eliminate nuclear weapons and decommission current arsenals.)

Project comparisons
Engineers estimate that as the rooms are filled with waste, the salt formation will creep in on the waste from 2 inches to 4 inches per year, eventually reaching the waste and forming a tight cocoon. This process will take several hundred years.

WIPP has a sister project at Yucca Mountain, Nev., that is undergoing reviews and studies, but there are striking differences that are worth noting.

According to Mager, the WIPP site is a final encapsulation for this waste. At Yucca Mountain, the interior of the storage site is composed of volcanic tuft. It is a retrievable site - meaning the waste can be brought back to the surface for reprocessing if that ever proves necessary.

Another major difference is that the WIPP site has been ready to receive waste since 1986, while studies are still underway in Nevada.

Getting to WIPP
There are 23 sites nationwide that currently house nuclear waste that will be transported to the WIPP site; all of it, for the time being, will be transported by truck. DOE and the U.S. Department of Transportation (DOT) say this practice is safe, and that a significant number of checks and balances are in place to prevent any mishap.

While the first shipment from LANL arrived in March without any trouble, when the second shipment was scheduled a few days later, officials delayed the shipment for a few days, citing safety reasons.

LANL is near Santa Fe, a few miles south on Interstate 40. An early morning fog bank forced cancellation that day. Some say the government is being too careful, but WIPP opponents in New Mexico are particularly wary, even though the trip to the southeastern portion of the state isn't far from LANL.

To be selected for the project, truck drivers have to meet extensive criteria. They must have logged more than 100,000 road miles without incident, and seven years of continuous service. Drivers must stop every 100 miles or every two hours to check the load.

While the waste from New Mexico travels a relatively short distance, DOE expects nearly 38,000 shipments coming from sites in California, Colorado, Idaho, Illinois, Nevada, Ohio, Tennessee, South Carolina and Washington. Shipments must follow a specific route, closely monitored by the driver, who is constantly in contact with a satellite tracking system. If necessary, a load is given a police escort.

Low-level radioactive nuclear waste will be stored in vacuum-sealed drums or bins and then placed in secure Transuranic Packaging Transporter Model 2 (TRUPACT) containers. The TRUPACT containers have a familiar shape, looking a lot like giant Thermos® bottles. They are made of stainless steel, and are doubly contained, non-vented and several inches thick. The TRUPACT containers are 8 feet in diameter and 10 feet high. Containers have been tested with drops from a height of 30 feet onto an unyielding surface, exposure to a jet fuel fire at a temperature of 1,475 degrees Fahrenheit for a minimum of 30 minutes and drops onto a steel spike from 40 inches to test puncture resistance. Tests showed the container would hold its seal and prevent release of radioactivity to the atmosphere.

Officials believe WIPP will receive 17 shipments per week. Once a shipment reaches the site, another series of inspections is conducted to ensure no tampering has occurred. Workers also give the TRUPACT containers a radioactive sweep to test for errant contamination.

Next, the drums or bins are removed from the TRUPACTs and are swept for alpha/beta ray particles. The shipment is given several other tests for possible leaks, and finally is scanned to ensure bar codes on the containers agree with the bill of lading.

Going underground
Once all the radioactive tests are completed and necessary inspections and paperwork are finalized, workers take the drums or bins into an airtight room and prepare them for their 2,150-foot descent into the salt caverns. It takes little more than five minutes by elevator, which can hold 45 tons of weight.

There are four vertical shafts to the salt caverns: one for air intake; one for exhaust; one for lowering the waste and necessary equipment; and one to pull mined salt from the caverns.

A person's voice echoes off the concrete walls while descending, but halfway down that changes to a dull pitch. Lower down, the walls are formed of salt and laced with iron pyrite.

Tons of equipment are stored in the mine, including a half dozen golf-type carts used for tours and getting around the more than 8 miles of tunnels and storage rooms. The near absence of moisture means the equipment does not corrode; however, if it is brought topside again, it begins to flake and peel.

Safety of the mine
Because the disposal area is essentially a mine, it is inspected quarterly by the U.S. Mine Safety and Health Administration (MSHA). State mining inspectors also make frequent unannounced visits.

The southeast corner of New Mexico has several other salt recovering and processing mines. But because the federal government owns the 8-square-mile storage zone and a 2-mile buffer zone, there isn't any encroachment of industry on the WIPP site. The area also is saturated with working oil wells, but none of them has been drilled in the storage zone. Angle drilling for oil is a possibility, but unlikely, as DOE owns the mineral rights in the 8 square miles.

Additionally, Westinghouse officials who oversee the government contract check daily with their own staff geologists and hydrologists.

The underground salt cavern is also equipped with its own fire department, including an ambulance that can easily move an injured worker from the site up the elevator to a waiting medical care unit or topside facility. The fire department and ambulance crews underground work with miniature versions of the vehicles normally used aboveground.

Local reaction
Carlsbad is a picturesque tourist destination, mainly because of the Carlsbad Caverns National Park, but the WIPP site has overwhelming local support because it has created 850 jobs. It's not uncommon to see signs throughout the town that read "Congratulations WIPP" and "Finally" - referring to the first shipment of received waste.

Within the state, three environmental groups fought to have the project halted. The state also requested a delay until a hazardous waste permit was issued. Neither succeeded, as U.S. District Judge John Garret Penn ruled the shipment could proceed, since neither the state nor the environmentalists could show "irreparable injury" if the shipments were not delayed.

The state filed a lawsuit, but has dropped its legal challenge to the federal certification of WIPP after the first interstate shipment of nuclear waste arrived from eastern Idaho.

New Mexico Attorney General Patricia Madrid admitted it was unlikely the state could succeed in its efforts to keep WIPP from operating. The state's decision to abandon the lawsuit was partly due to a lower court ruling that the $2 billion facility did not require a special state hazardous waste permit to store nuclear waste that was not contaminated by other substances. The legal challenge by environmental groups was dismissed in July.

Argument for safety
DOE says it has done everything to ensure the safety of not only transportation of the nuclear waste, but also mine safety. Work at the site began 25 years ago, and the initial seven underground rooms have been ready for nuclear waste since 1986. Critics say the brine pockets make the cavern unsuitable since the brine could allow radioactivity to migrate to the surface.

Transportation of the nuclear waste has been meticulously planned. The TRUPACT was developed specifically for transporting the waste.

Most of the transportation will take place on interstate highways, which are in relatively good repair. DOE has invested $230 million to build a four-lane highway (State Highway 285) from Interstate 40 south to Carlsbad.

Shipments from the east won't use the new stretch of highway, since they will drive south to Interstate 20 and turn north to the storage site. That road is already a four-lane road.

WIPP officials contend safety has been the site's primary goal since work started in the salt beds in the early 1980s. They also emphasize that underground testing is an ongoing process. Monitoring the shipments, containers and waste, according to officials, is the site's top priority.

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This article originally appeared in the 09/01/1999 issue of Environmental Protection.

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