(NVR) - Napa County planning staff supports having wineries show they are following key county rules by submitting annual reports with data needed for proof.

Wineries in unincorporated areas would certify how much wine they are producing and whether they are complying with their use permits. Each winery’s principal officer would sign the report.

That and the accompanying data would allow the county to know whether wineries are within their production limits and, if required, are using 75 percent Napa grapes.

It’s the latest wrinkle in an ongoing discussion by the county’s Agricultural Protection Advisory Committee. The 17-person committee meets at 9 a.m. Monday at the county Administration Building, 1195 Third St.

The committee discussed similar winery self-certification proposals on July 13. But it failed to pass the idea by the needed two-thirds vote in part because some committee members worried the county couldn’t keep proprietary winery information a secret.

“I think we’re heading down the right trail with this format,” said committee member Jeri Gill of Sustainable Napa County as the meeting neared an end.

Now, county Planning, Building and Environmental Services has presented a “staff proposal” for annual winery self-certification.

The county could legally keep from the public such information as state Department of Food and Agriculture-related data used to calculate wine production, a county report says. It could not keep secret such information as visitor counts and marketing activities.

Figuring out whether wineries are within their visitation caps is “particularly problematic,” the staff proposal says.

“Wineries generally maintain log books or other means of counting visitors, but log books cannot be verified for accuracy,” the proposal says. “To be credible and to allow for successful prosecution of violations, standards must be defined and quantifiable.”

The committee on July 13 debated how long a winery with a violation might have to come into compliance. Suggestions ranged from immediately to one year to three years.

The staff report proposes that a winery must immediately comply with its use permit. Among other things, to do otherwise creates an unfair business advantage, it says.

Napa County has no process for determining civil penalties for wineries with violations, the staff proposal says. As a result, it is difficult for businesses and the public to understand the potential consequences of illegal behavior.

The proposal suggests the county prepare a formula for calculating civil penalties.

Enforcement and compliance review fees could support the cost of the expanded winery compliance program, it says. But it mentions no amounts.