Sierra Club sues DNR over Port Washington data center project permitting - BizTimes

The Sierra Club has initiated a lawsuit in Ozaukee County Circuit Court against the Wisconsin Department of Natural Resources (DNR), seeking to overturn the agency's decision to forgo an environmental impact statement (EIS) for the Vantage Data Center project in Port Washington. The complaint also aims to nullify the air pollution control permit granted for the $15 billion, 2.5 million-square-foot facility, which is currently under construction and slated for use by Oracle and OpenAI.

The Sierra Club argues that state environmental rules mandate an EIS for projects significantly impacting the human environment. Their complaint highlights potential adverse effects on construction, water quality, air quality, public health, wildlife, recreation, and climate change. The organization also notes that the DNR had initially indicated an EIS would be required, citing July 2025 emails from Deborah Tomczyk, an attorney for Vantage, to company leaders, detailing conversations with DNR attorney Molly McNab, who explicitly stated an EIS would be necessary given the project's scope and scale.

Despite these prior indications, the DNR released an environmental analysis summary on December 9, and two days later, determined its obligations under relevant environmental regulations had been met without requiring a full EIS. The Sierra Club's lawsuit contends that the DNR erred by not considering the project's connection to broader electrical transmission and generation projects and by failing to account for a planned second phase of the Vantage project. Hearing dates for the case have not yet been set.