What's the problem with removing zoning? Which I interpreted, charitably, as "remove low-density zoning" and not as "let anyone build a lead smelter in their yard". (Also, a suburban area is probably not a lead smelting operation's preferred location anyway).

Environmental impact assessments are great if they actually do what they say. But they can also be weaponized to block any new development in existing cities. Forcing suburban sprawl into less populated areas is a worse outcome if you want to protect the environment.