The company that created the Love Canal toxic waste dump knew that what it was doing was wrong but foisted the filled-in property off on a school board anyway, a state lawyer charged Wednesday.

Eugene Martin-Leff said Hooker Chemicals & Plastics Corp. officials were warned as early as 1945 that the chemicals buried at Love Canal were toxic but did not pass those warnings on when it sold the property to the Niagara Falls school board in 1953."The evidence in this case will show a company that chose its own narrow self-interest over the interest of the community," Martin-Leff said in opening arguments in federal court. "Voices of conscience were raised within that company but were overridden by the pursuit of financial gain."

Occidental Chemical Corp., which purchased Hooker in 1968, has said it warned the school board repeatedly not to dig into the site. But Martin-Leff said the warnings were not specific enough.

"There was no warning to keep the site fenced," he said. "There was no warning, `Do not grade or level to make a parking lot for the school.' "

The trial is to determine whether Occidental is solely responsible for up to $700 million in cleanup costs and damages.

The company argues that the federal, state and Niagara Falls city governments and the city's school board share liability.

Before opening arguments Wednesday, Occidental Chemical President Roger Hirl apologized for the disaster at Love Canal. "We do feel badly about it," he told reporters. "We apologize to all those who suffered because of it."

Testimony could take six months. U.S. District Judge John T. Curtin, hearing the case without a jury, is expected to issue a final ruling in about two years.

Evidence includes up to 1 million pages of documents. A computer system has been installed in the courtroom to keep track of all the paperwork.