A planned $6.6 billion expansion of the zinc plant in Clarksville is drawing support from local and state leaders, along with questions about what increased smelting could mean for nearby residents and the Cumberland River area. Korea Zinc bought the existing 1,200-acre site from Nyrstar in April. The expanded operation, to be called Crucible Metals, is expected to create 740 jobs. President Donald Trump highlighted the investment during a Clarksville visit, crediting his tariffs for the company’s plans. The project is described as Tennessee’s largest single private corporate investment. Clarksville Mayor Joe Pitts welcomed the project, saying the country needs critical minerals. He described the operation as a joint venture involving Korea Zinc and the U.S. Department of Defense, and said it would expand the existing zinc plant to roughly twice its current size. State Rep. Ronnie Glynn, a Clarksville Democrat, also voiced support. At full operation, the facility is projected to process 300,000 tons of zinc, more than twice current capacity, as well as 200,000 tons of lead, 35,000 tons of copper, 1,040 tons of silver and 5 tons of gold. The metals are used in industrial and supply-chain applications, and the project’s backers cite domestic production as an economic and national-security benefit. The plant sits along the Cumberland River, minutes from neighborhoods and an outdoor academy for children. Pitts said the site is closely monitored and meets environmental requirements. Korea Zinc’s chairman has pledged the company will prioritize environmental stewardship and safety, according to a statement provided to Tennessee economic development officials. But assurances have not settled concerns about health impacts. Author Caroline Fraser, whose book examines pollution linked to a former smelter in Tacoma, Washington, urged communities to weigh health risks before accepting such facilities. She said smelting can release particulate pollution and byproducts, including arsenic, depending on the materials and processes involved. Those concerns do not establish what emissions the Clarksville facility will produce; residents will need plant-specific information and ongoing oversight to assess the risks. Pitts also pointed to $40 million included in Gov. Bill Lee’s budget for improvements to Cunningham Bridge, which he said would benefit plant workers and residents who cross the river. The project’s scale means the jobs and investment will be accompanied by lasting questions about transparency, emissions monitoring and public access to environmental data.