Email Record: Walls and waivers : expedited construction of the southern border wall and collateral impacts to communities and the environment : joint oversight field hearing before the Subcommittee on National Parks, Forests, and Public Lands, joint with the Subcommittee on Fisheries, Wildlife, and Oceans of the Committee on Natural Resources, U.S. House of Representatives, One Hundred Tenth Congress, second session, Monday, April 28, 2008, in Brownsville, Texas.