A landmark pollution case now before the Yokohama District Court is exposing the dirty underbelly of incineration practices in Japan, and highlighting what some would call the willingness of officials to turn a blind eye to dangerous waste burning.

Toxic smoke billows from the Envirotech incinerators to hang low over Atsugi.

The plaintiff in the case is the U.S. government, specifically the Department of Justice. The defendant is a private incinerator in Ayase City, located next to the U.S. Naval Air Facility in Atsugi, Kanagawa Prefecture. The Justice Department is seeking a karishobun, or provisional injunction, requesting that the court shut down the incinerator.

Consider these numbers: In Japan, if dioxin levels in soil exceed 250pg-TEQ (toxic equivalent) per gram, an investigation is warranted. Soil samples on Atsugi base have revealed dioxin levels as high as 330pg-TEQ per gram. These levels are nearly 750 times higher than found in control samples taken from beneath a building that predates the incinerator.

But it gets worse, much worse. Under national guidelines, dioxin levels reaching 1,000pg-TEQ per gram warrant remedial action, such as soil removal. Soil samples taken on property abutting the incinerator found dioxin levels increasing from 1,888pg-TEQ per gram to 3,926pg, 5,293pg and 8,859pg. The latter figure is nearly nine times higher than the trigger for remedial action.

If soil samples were taken closer to the incinerator and its fly ash hoppers, dioxin readings could soar to unheard-of levels.

The plaintiff's complaint, filed last March, states that Atsugi base "is heavily contaminated with dioxin, heavy metals and other toxic substances, because the air over the base is and has been contaminated for a substantial period of time during each of the past 15 years."

The complaint further claims that "the base is subject to routine fumigation by thick, foul-smelling smoke, laden with dioxin, heavy metals and other toxic substances, from [the smokestacks of] the Defendant's Incinerator Facilities."

In their reply, lawyers representing the facility argue that the incinerator is "disposing of general and industrial waste for Kanagawa Prefecture and numerous other municipalities, major corporations, etc., and thereby making a significant contribution to society, without violating any domestic laws or regulations."

Furthermore, "the Ministry of Health and Welfare has actively promoted incineration as the way to contribute to the reduction of waste. Therefore, in the event the Defendant is prohibited from operating its incinerator facilities, we would like to point out that none of the incinerator facilities in Japan would be able to operate."

The panel of three judges hearing these proceedings faces a thankless, and inevitably controversial, task. If they accept the plaintiff's arguments, the judges will have to shut down a business that holds valid permits issued by prefectural authorities.

By concluding that the defendant is indeed emitting dangerous levels of dioxins and other pollutants (despite permits and some efforts to "clean up"), the judges will effectively be indicting prefectural and national authorities who have stonewalled complaints from the U.S. Navy for the past decade. This in turn could spur further serious doubts about the sincerity and efficacy of incinerator oversight nationwide.

On the other hand, if the court rejects the plaintiff's request for a provisional injunction, it will be ignoring shocking dioxin levels and the dangerous conduct of the defendant, and thus rejecting both the spirit of Japanese law and the tenor of the times. Today, in Japan and abroad, it is acknowledged that there is no safe level of dioxin exposure. As the United Nations Environment Program concluded almost two years ago, "every effort should be made to reduce exposure to the lowest possible level."

I first visited the base and incinerator in the spring of 1998, and that summer I wrote several columns on the Navy's test results. At that time, the incinerator complex was known as Jinkanpo, meaning "God protects the environment." The irony of this moniker was not lost on base residents. As one noted wryly, "God had better protect our environment, because no one else is."

One of the columns I wrote that summer began, "Just as Minamata is synonymous with mercury poisoning, Jinkanpo may soon become a household word connoting Japan's high-risk incineration practices." I was wrong.

Jinkanpo did gain notoriety, and Japan's incineration practices have come under closer scrutiny. Standards and guidelines for incinerator operations have been tightened. But Jinkanpo never gained the widespread infamy I predicted. Like so many businesses and politicians that face scandal in this country, Jinkanpo bowed out -- and reinvented itself with a shiny new, ah, name. Today Jinkanpo looks much the same as it did in 1988, but it is now called Envirotech.

In 1999, after years of complaints from Navy officials, Japan's Environment Agency and the Ministry of Health and Welfare agreed to cooperate with the Navy in joint monitoring. The results confirmed what the Navy already knew, and Kanagawa Prefecture sent Envirotech an administrative order directing the incinerator owner, Tetsuro Murata, to install bag filters, a filtration system widely used in incinerators.

Envirotech is a sight to behold. Three incinerators topped by stubby smokestacks spew out smoke of varying colors and consistencies, depending on the day and who is watching. Trucks rumble down a dusty road into the complex, dumping waste into hoppers and onto the ground. The Tade River runs through the complex, collecting runoff from the waste and highly toxic fly ash and bottom ash that are piled out in the open and scatter when the wind blows.

Atsugi base sits on a plateau about 16 meters above the incinerators. The smokestacks rise a scant 23 meters. This means the stacks stand only 7 meters above the base's ground level. On both days I visited, smoke was blowing toward the base, and a "downwash" effect was causing the smoke to billow across playing fields into base housing and schools.

Under American law, a temporary injunction proceeding may last just a day or up to a week or two. In Japan, provisional injunctions take longer, but generally no more than two or three months at the most. The Envirotech-Atsugi proceedings are now approaching their first anniversary. The last hearing was in mid-December, the next will be Thursday.