By the time federal prosecutors warned Isleton officials that a planned medical marijuana farm there was illegal, the project's workers already had quietly brought in more than 1,000 marijuana plants, according to a Sacramento County grand jury report issued Monday.

The warning in May from U.S. Attorney Ben Wagner had an immediate impact: A worker from Delta Allied Growers pulled the plants out of three vacant homes on the site and buried them 10 to 15 feet underground, and the project was abandoned, the report found.

The 12-page report is the product of a grand jury probe that began in April and concludes that Isleton officials were blinded by an offer of $25,000 in monthly payments from the growers.

"The city allowed the community to be pushed into a project that is perched on the blurry edge of marijuana law without properly questioning the situation," a cover letter to the report from grand jury foreman Donald Prange Jr. reads. "It did so, not because of any desire to test the limits of the law, but because of the promise of money and jobs."

The report questions the actions of City Manager Bruce Pope and Police Chief Rick Sullivan, whose department was promised a sophisticated security system for the town by the growers.

"Neither one seemed to worry about the legal status of the project under federal law," the report states.

It also singles out City Attorney Dave Larsen, who was paid by the marijuana growers $100 an hour over his city-paid rate to "help expedite the procedural aspects of the application" for the farm.

That arrangement "suggests an improper financial interest in the project," the report states.

Pope said Monday that city officials did nothing wrong, and that they were unfairly targeted by District Attorney Jan Scully.

"We did our jobs the way we were supposed to," Pope said. "The fact that a criminal prosecutor didn't like the way we did our jobs is beside the point."

He added that he did not know of any plants at the site.

Pope said he heard rumors early on that plants were being grown there and went out and inspected each of the empty homes and garages, then went back out and did so again after he heard the grand jury had been told plants were on the site.

"One of our agreements was that there would be no plants brought to that property until the growing facilities and the internal security and external security with cameras and computers and all the support equipment was operational," he said. "We never got to that point, so there never should have been any plants out there.

"If it turns out there were, that's something I'm not going to be pleased about."

Delta Allied officials did not respond to a request for comment.

No criminal charges have been filed in connection with the probe, and the grand jury made it clear that the investigation by Scully's office may not be over.

The grand jury, which summoned the entire city government for secret testimony in April, offered immunity to all witnesses except for Larsen and Michael Brubeck, the owner of Delta Allied Growers.

Isleton, a Delta town of about 840 residents with perpetual money woes, was first approached by Brubeck in July 2010.

The 15,000-square-foot project was to be built on the northern edge of town in a city block where 18 new homes had been built just before the housing bust. The homes were empty, and Brubeck's workers envisioned constructing a series of grow houses behind secure fencing to grow the marijuana.

The business plan called for the plants to be sold to dispensaries in Southern California operating under the state's medical marijuana law.

No one bothered to seek advice on the legality of the project from either federal officials or Scully's office, the report found, adding that Brubeck's operation promised to pay the city as much as $600,000 in just the first year of operation.

The source of the company's funding is still unclear. One employee told the grand jury that a company in China had invested $1.3 million in Delta.

The company began paying Isleton $25,000 a month last fall as Delta began work at the site, and by April six grow houses were being constructed.

Scully's office notified the city in February that it had serious questions about the legality of the project, but Isleton officials rejected her concerns.

Despite Scully's questions, Delta Allied workers brought in more than 1,000 immature marijuana plants and placed them inside the garages of three model homes on the site, the report states.

"Garden hoses provided irrigation and generators provided power for fans and lights inside the garages," the report states. "The lights were on and fans were running day and night.

"One witness testified no lights were visible because there were no windows in the garages."

Workers continued to cultivate the plants until early May, when Wagner's written warning arrived and the plants were buried, the report said.

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