Protesters said it doesn't matter that the agency has no plans to produce nuclear components at the campus site. They don't want the agency to have any presence in the city.
Cañoncito residents for decades have been plagued with well water that is either toxic or runs low during a dry cycle.
Forest Service hopes to convince judge to remove injunction on timber activities in six forests.
Critics contend the decision runs counter to a 1998 court order that requires a full environmental analysis when two or more sites are involved in pit production or when the government plans to manufacture more than 80 pits yearly.
Consent order in 2016 replaced more stringent requirements from 2005.
More than 15 residents showed up, and several State Land Office scientists came to explain the rationale behind the tree thinning.
Lab officials say the 2016 consent order created more flexible goals for tackling an immense cleanup with unforeseen problems, while critics contend it defanged an enforcement action that was getting results.
U.S. Fish and Wildlife Service biologists issued mostly favorable opinions on how thinning trees and salvaging fallen timber can help suppress wildfires that could threaten the species.