Positions for general laborers and custodial laborers, W-2 and W-3, National Institutes of Health, Bethesda, Md., Army Map Service, 6500 Brooks Lane NW., Washington, D.C., Atomic Energy Commission, Germantown, Md., David Taylor Model Basin, Carderock, Md., National Naval Medical Center, Bethesda, Md., Naval Ordnance Laboratory, White Oak, Silver Spring, Md., and other Federal agencies located in Montgomery County, Md., announcement B-30-1(61), local.