Nearly two months after an explosion at a fireworks facility in the rural Northern California town of Esparto took the lives of seven men, new documents uncovered in a Public Records Act request reveal that Yolo County officials were aware the site housed fireworks dating back to 2022, three years before the blast. 

County officials told CBS13 soon after the tragic blast that the site was not permitted at the local level to store fireworks. The property was zoned only for agricultural use. 

Still, email exchanges between county building officials detail that many people knew what was happening on the property, including Esparto's fire chief, Curtis Lawrence. 

In an email dated June 2, 2022, Yolo County's chief building official, Scott Doolittle, wrote, "I received a tip that the site is being used to run a pyrotechnics business. Sheriff deputies, potentially including deputies that we work with, are reported to be involved in the business. They are using an ag exempt building plus 25 Conex boxes for the operation."

Doolittle went on to write that he would "tread lightly," given that connection to the sheriff's office, and then "we can discuss how to proceed."

That email came just one day after Doolittle raised concern that a contractor asking for a permit on that property for a "metal storage building" was requesting too much electricity — so much that it would no longer qualify as an ag-exempt building. 

"Ag exempt structures are only allowed a very limited power supply and this is our first indicator that the use in the building is not consistent with an ag exempt structure. It is a red flag that should be raised as soon as possible," Doolittle warned in an email to multiple colleagues.

Yolo County Sheriff's Lieutenant Sam Machado and his wife, Tammy, owned the property that housed two fireworks companies: Devastating Pyrotechnics, owned by Kenny Chee of San Francisco, and Blackstar Fireworks, owned by Esparto volunteer firefighter Craig Cutwright.

Sam and Tammy Machado are now on administrative leave from their jobs at the sheriff's office.

In an email dated June 3, 2022, Doolittle updated his colleagues that he talked to Esparto Fire Chief Curtis Lawrence and that Lawrence, "...confirmed that the pyrotechnic business is licensed through federal ATF. We will still be reaching out to get local regulations, but I expect cooperation from the pyro business."

Both fireworks businesses did have state and federal licenses to operate. The licenses have since been revoked by Cal Fire following the explosion.

The June 3, 2022, email also reads, "Curtis also said the 25 grouped containers are 'safe and sane' fireworks and act as a distribution center, whereas other smaller groups of containers are the ones that contain the more dangerous materials..." 

On the same day, an email from another county official, Moushumi Hassan, stated, "If the facility is handling new or waste fireworks... they need to submit a Hazardous Material Business Plan... it will be added to our database and inspected at least once every three years." 

Though Chief Lawrence and Yolo County officials had visited the site, no official or formal safety inspections were ever completed. 

In response to these public records, the Yolo County Board of Supervisors issued a statement saying that Building Division staff visited the property and confirmed that display-grade fireworks were stored in ATF-licensed shipping containers. These fireworks were not associated with what exploded in the incident and were recovered by Cal Fire afterwards. 

The statement from the board reads, "No fireworks or other hazardous materials were observed during the Building Division's mid-2022 visit. The property owner and building contractor consistently represented that the new building under construction would be used only for agricultural purposes." 

County officials say after that review, the Building Division reported its findings promptly to department leaders and code enforcement. 

"No further enforcement action occurred, and Building Division staff did not return to the site or take other actions relating to fireworks at the site after mid-2022. Evidence from Google Earth images and media reports suggests that display-grade fireworks storage and handling increased greatly after mid-2022. However, neither the Building Division nor Code Enforcement received reports or complaints about such activity. Also, as the County has previously stated, at no time did the County receive any applications or issue any permits, licenses, or other approvals authorizing fireworks storage, handling, or other activities on the property," the board's statement reads. 

Documents also reveal that county officials warned the buildings on the property were not designed for people to work inside and that they did not have any basic fire protection systems. 

Cal Fire's investigation into how the explosion happened and if any criminal charges will be filed in relation to its cause is in the final stages, State Fire Marshal Daniel Berlant told CBS13 Friday.

"Does it concern you that county officials were aware fireworks were on the property but then that there wasn't anything done about it from what we can tell?" I asked Berlant. 

"It's been clear this case has exposed the numerous amount of loopholes between requirements at the local, state and federal level," said Berlant. 

Berlant confirmed that dozens of search warrants have been served as part of the criminal investigation by Cal Fire, ATF and the Yolo County District Attorney's Office.

The DA confirmed to CBS13 Friday night that a search warrant was served on Esparto Fire Chief Curtis Lawrence, his home and personal property in addition to the Esparto Fire Department. 

"There will likely be recommended charges that we bring forward. What those look like, and to who, is what we are continuing to wrap up," said Berlant. 

Yolo County officials say they launched an internal review of the county's code enforcement procedures, processes and staffing.