Burying hazardous waste in salt domes could be one answer to a problem causing considerable stir in Washington, in executive board rooms, and in communities.
United States industry now turns out an estimated 225 million to 275 million metric tons of these wastes a year, of which 45 million metric tons fall under federal control, according to the Environmental Protection Agency (EPA). This total is expected to grow each year.
''Domal salt is strong, plastic, impermeable, and nonreactive to virtually all chemicals,'' says Tom Noel, a former assistant secretary of the Department of Energy who once headed the Strategic Petroleum Reserve program. ''Salt domes may be easily mined to form huge disposal cavities far below and isolated from ground-water supplies by hundreds of feet of rock salt.'' The US has its entire strategic reserve of crude oil, more than 300 million barrels, stored in salt.
Mr. Noel is now president of Empak Inc., a Houston-based subsidiary of Pakhoed USA. His company is working on dome-salt storage of hazardous waste, a method now being used in Europe.
Up to now, the most common method of waste disposal has been placement in landfills and lagoons. The danger of these methods lies in liner deterioration, which results in contaminated material seeping into the ground water. This is what happened at Love Canal and may happen again, according to Jan Geiselman, director of planning and development for Pakhoed and former regional head of EPA's Air Waste Management Division. Ms. Geiselman directed the Love Canal cleanup.
''The clay cap we put on Love Canal is a temporary solution,'' she said. ''The clay will eventually leak.''
Other methods of disposal include incineration; deep-well injection; and physical, chemical, and biological treatments - all of which have potential dangers. Incineration is expensive and can release uncombusted material into the atmosphere. Physical, chemical, and biological treatments produce sludges and reduce volume, but are usually insufficient alone and can release trace contaminants. The exact location of the waste is unknown after deep-well injection.
If Empak's plans to store waste in domes comes to fruition, the residents of the Gulf of Mexico coastline will be those principally affected. This coastal region contains 524 known domes, ranging up to 12 miles in diameter and several miles in height.
Empak is proposing a $100 million multiuse storage facility deep within a salt dome near Vinton, La., for petrochemical-product storage as well as disposal of industrial waste, according to Mr. Noel. The company has obtained an option on 180 acres on the 35,000-acre family-owned ranch of Matilda Gray Stream , which is close to the Intercoastal Waterway. Start-up is planned for 1985, after all necessary permits are obtained from state and federal agencies.
Empak plans to use solution-mining technology (dissolving the salt by pumping water in and then removing the brine) to create what the company calls ''string of pearl'' caverns - vast vaultlike cavities vertically stacked in the deep rock salt. Waste will be pumped down into the cavity through a casing string consisting of five layers of steel and three layers of cement. Containment will be far below drinking-water aquifers, Mr. Noel said. The Vinton salt dome is large enough to hold 3,000 buildings the size of the New Orleans Superdome.
''As an additional safeguard, every waste load will be tested to ensure compatibility with the salt cavity and its contents,'' Mr. Noel said.
''Containment is so complete that pockets of brine water and gas, entombed 100 million years ago in the dome's infant stages, have been found intact during salt-mining operations,'' he added. ''Salt domes are impervious to earthquakes and faults - indeed, government experiments detonating devices equivalent to 3, 000 tons of TNT in salt domes produced no breaching and cracking of only a few feet adjacent to the blast.''
But few communities are comfortable about storing hazardous waste in their backyards, and the residents of Vinton, La., are no exception. A ''roar of protest'' has erupted since the project was announced, according to Debbie Kebodeaux, a reporter for the weekly Vinton News. A Citizens Environmental Action League has been formed to oppose the proposed facility, and Louisiana state Sen. Cliff Newman and state Rep. Burton Andreport have come out publicly against the project.
Empak is now involved in a massive public relations campaign to show that all possible precautions against accidents, spillage, environmental damage, and so forth have been taken. The company asked for and received a $100 million insurance policy against bodily injury and property damage from Lloyd's of London.
But the residents of Vinton are unconvinced. ''We know it's experimental, and we don't want to be guinea pigs,'' Ms. Kebodeaux said. ''The same scientists that were telling us clay liners were safe 10 years ago are now saying salt is safe. I don't think they can gain the acceptance of this town.''
Those in the underground-storage industry call the proposed project ''extremely safe.'' The hazardous waste is heavier than water and should have no tendency to float upward and escape. Highly volatile liquefied gases have been successfully stored in underground caverns under high pressure for the last 30 years in much more severe conditions, according to Neal Van Fossan, vice-president of Texas Brine Corporation and chief engineer for the Strategic Petroleum Reserve.
''The term 'hazardous waste' scares most people, but given time, I think the people of Vinton are going to see that what we are offering is safer than the landfills and lagoons where such waste is currently stored in this area,'' Mr. Noel said.
The waste will be tested for compatibility with other waste in storage, he added. The following are some of the planned precautions: The barge dock, truck unloading pads, and other surface areas would include concrete containment areas for any spillage or leakage. Accumulated waste water and rainwater would be collected from the containment areas and disposed with the rest of the waste material. Trucks and barges would be cleaned after unloading. The material, in slurry form, would be analyzed, preblended, and diluted. Nor would any drilling be allowed near the site.
If this project is successful, Empak intends to start similar operations elsewhere along the gulf coast and in other sections of the US.