California regulators say a Silicon Valley tech entrepreneur and winemaker has agreed to pay $3.76 million in penalties after his company bulldozed a protected wetland and filled in a stream bed to build a vineyard in Mendocino County.

The Santa Rosa Press Democrat reports Saturday that the settlement is one of the largest ever involving water quality on the North Coast. It stems from a litany of environmental violations tied to unpermitted work by Rhys Vineyards on owner Kevin Harvey’s ranch near Laytonville.

Rhys’ lawyer said in a statement that the company “deeply regrets the mistakes made.” Harvey, a San Francisco Bay Area venture capitalist, could not be reached for comment.

Officials say the company illegally covered protected wetlands and filled in a stream bed near the North Fork Ten Mile River watershed.