SACRAMENTO, Calif. — Yolo County officials failed for years to shut down an illegal fireworks operation in Esparto despite repeated warning signs, a civil grand jury report released Thursday found, a lapse that preceded a July 1 explosion that killed seven people.

The grand jury, separate from a criminal grand jury weighing possible charges related to the blast, investigated how the illegal facility operated for years in rural Yolo County in violation of county ordinances.

The report, titled “Officials Knew, None Acted,” criticized the county’s code enforcement practices for allowing the unpermitted facility to warehouse fireworks. It also questioned whether the facility’s ties to Yolo County Sheriff’s Office employees contributed to lax oversight of the property.

The grand jury reviewed public records, toured the blast site and spent more than 40 hours interviewing public officials.

Grand jury foreperson Richard Zeiger said the panel conducted its work in secret and began shortly after the July 1 incident. The criminal grand jury, impaneled by prosecutors in Yolo County District Attorney Jeff Reisig’s office, have yet to hand up any indictments related to the blast, following the conclusion of Cal Fire’s investigation of the blast, which was handed over to Reisig’s office in February.

In an interview, Zeiger called the explosion a tragedy and “a heavy lift for Yolo County when it comes to expending resources. I believe that DA Reisig is serious about the investigation the DA’s Office is conducting. We worked hard to do our part.”

But the civil report produced by the 19-member panel serving a one-year term, highlights a pivotal moment in June 2022, when county building officials became concerned about a new warehouse constructed on property owned by Yolo County sheriff’s Lt. Sam Machado and visited the site.

But, according to the report, “following the site visit, the County Community Services Department took steps toward a possible enforcement action against the property. But within days, this conversation about the site — at least in email records provided by the county — abruptly ceased. The department failed to take any action, and the fireworks business continued to quietly operate and even expand.”

Although the report did not specifically name Machado — or his wife, Tammy, a Sheriff’s Office employee — it found fault with potential conflicts of interest involving the lieutenant and oversight failures by the Sheriff’s Office, which is responsible for monitoring outside employment and income.

“The sheriff lieutenant failed to obtain the required prior approval from the sheriff for his financial interest in the fireworks business on his property,” the grand jury found.

Both Machados have been on leave since the incident.

The report concluded that Machado’s connection to the business likely contributed to lax enforcement of clear county violations.

“Combined with the fact that the property was owned by officials who worked for the Sheriff’s Office, this approach seems to have contributed toward employees turning a blind eye toward a violation that eventually allowed an illegal business to expand and ultimately resulted in the death of seven people, destruction of the residential and commercial buildings on site, a 78-acre fire and damage to residences, buildings, and agricultural acreage on surrounding properties.”

The grand jury, which expires at the end of June, has limited criminal authority — but the report stated it was reserving the right to pursue charges if it finds “willful or corrupt misconduct in office of public officers of every description within the county.”

The use of that authority under Penal Code 919(c) is rare, and penalties are generally limited to removal from office.

The grand jury also found that numerous county officials knew about the illegal fireworks operation for years, yet “inexplicably, no code enforcement occurred,” adding that dangerous fireworks have been banned in rural Yolo County since 2001.

One possible explanation, the report said, was a belief among county officials that state and federal agencies were responsible.

“County officials believed that state and federal officials, who had issued licenses for the businesses, were in fact responsible for monitoring the businesses,” jurors said in the report. “The grand jury did not discover any evidence that the County had checked with these agencies. There is no record of Cal Fire ever inspecting the property.”

The report added that “The grand jury has identified nearly a dozen county employees who knew over the years of the pyrotechnics operations at the Esparto site but failed to take any remedial action. County records show communication between most of these employees, some now retired, concerning the Esparto fireworks site. Despite this, there is no record that any of them advocated for enforcement of existing county ordinances.”

The grand jury also found the county missed enforcement opportunities due to poor interdepartmental communication, misunderstandings of permitting requirements and a longstanding practice of deprioritizing code enforcement.

“The Board of Supervisors has repeatedly rejected attempts to augment enforcement activities,” the grand jury found. “Further, the Grand Jury heard testimony that County employees believe the Board of Supervisors wanted them to take a tolerant approach toward code violations that seemed minor.”

The grand jury issued 16 recommendations to the Board of Supervisors, the Department of Community Services and the Sheriff’s Office, largely focused on improving communication, strengthening enforcement and training employees.

The Yolo County Board of Supervisors said it “respectfully disagrees with the report’s suggestion that the county does not take code enforcement seriously,” the county said in a statement BEFORE/AFTER the report’s release.

The county has 90 days to respond formally and has already launched a review of its code enforcement processes.

Separately, a Cal Fire task force has issued preliminary recommendations in the wake of the inferno. State Sen. Christopher Cabaldon, D-West Sacramento, introduced a bill to strengthen fireworks enforcement in September.

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