Metalclad Makes Third Mexico Deal : Environment: Anaheim firm starting its latest joint venture to build hazardous-waste treatment plants south of the border.

Metalclad Corp. said Monday it is starting its third joint venture with a Mexican company to build hazardous-waste treatment plants in that country.

The Mexican concern--a waste-disposal company called Eliminacion de Contaminantes Industriales--is acquiring a site in the Mexican state of Tamaulipas, on the east coast of Mexico below the Texas border.

Two other Mexican companies have already acquired sites to build plants with Metalclad: one in the state of Veracruz, on the east coast below Tamaulipas, and one in San Luis Potosi, inland and north of Mexico City.

All three sites are in Mexico’s industrial region near the central part of the country.

Metalclad’s part in the venture is providing money; the Mexican companies are securing construction permits and lining up customers. A second U.S. company, Molten Metal Technology of Cambridge, Mass., is providing the technical expertise.

MMT, says Metalclad, has pioneered a more effective, cheaper way of disposing of toxics.

Metalclad, which lost nearly $1 million last year on revenues of only $24 million, says it will either borrow the money to build the plants or raise it by selling more stock.

Metalclad is a 50-year-old company that started out in the business of insulating petrochemical plants.

The company gradually expanded into insulating hotels, schools and other buildings and--in the 1980s--also moved into the business of removing asbestos installation from buildings.

With losses mounting, one of the company’s biggest shareholders, a real estate investor named Grant S. Kesler, persuaded the board of directors to fire the company’s president and install him in the job.

Since that change of management in July, Kesler has pushed the company back into its first business--servicing petrochemical plants. He’s also pushed the expansion into this new business of building hazardous-waste treatment plants in Mexico.

The first phase of the first plant--in San Luis Potosi--is expected to open later this year.