Lower Sandia Canyon Floodplain Assessment for the New Mexico State Route 4 and East Jemez Road Intersection and Technical Area-72 Shooting Range Facility at Los Alamos National Laboratory
The National Nuclear Security Administration (NNSA), a semi-autonomous agency within the U.S. Department of Energy (DOE), is proposing to take actions within the lower Sandia Canyon floodplain. These activities consist of modifications and upgrades to the intersection of New Mexico State Route 4 (SR4) and East Jemez Road and installation of a 4-wire fence and a prefabricated bridge at the Technical Area (TA)-72 Shooting Range Facility. The purpose of the proposed modifications and upgrades is to improve safety and increase the capacity and efficiency of the intersection. Road and intersection upgrades will add extra lanes to both SR4 and East Jemez Road in the vicinity of the intersection and will require widening both roads. Widening East Jemez Road will encroach on the 100-year (100-yr) lower Sandia Canyon floodplain.
In support of recent modifications and upgrades to the TA-72 Shooting Range Facility the installation of a 4-wire fence and a prefabricated bridge are necessary. Both the fence and bridge cross the lower Sandia Canyon channel and floodplain east of the shooting range.
NNSA has prepared this floodplain assessment in accordance with 10 Code of Federal Regulations (CFR) 1022 Compliance with Floodplain and Wetland Environmental Review Requirements, which was promulgated to implement DOE requirements under Executive Order 11988 Floodplain Management.
See December 2019 Floodplain Statement of Findings Technical Area-72 Shooting Range Facility and Withdrawal of the Floodplain Assessment for the New Mexico State Route 4 and East Jemez Road Intersection at LANL.