Zentner Planning and Ecology was hired to complete due diligence biological work on a potential solar site located south of the Napa Airport in Napa County. This was a complex site with horse pastures, seasonal wetlands, and other sensitive habitat. Our preliminary delineation work determined that the site contained a portion of a tidal marsh and a number of seasonal wetlands. As well, we determined that sensitive species could be an issue depending upon project design and layout. However, we were able to show that a good portion of the site was likely upland and, therefore, could be developed with little to no impacts to wetlands or other jurisdictional areas, while keeping potential species issues to a minimum.