Navajo UMTRA LTSM Update - US Department of Energy

NAVAJO UMTRA LTSM UPDATE Madeline Roanhorse Navajo AML / UMTRA Department 2010 Long-Term Surveillance and Maintenance Conference Grand Junction, Colorado Navajo UMTRA LTSM Update Background and History Shiprock site Mexican Hat site

Tuba City site Contact Information Navajo UMTRA Background and History

Cooperative Agreement exist between the Navajo Nation and DOE to address the former surface cleanup and the current ground water remediation activities at the four Navajo sites Three Navajo sites located at Shiprock, NM; Mexican Hat, UT; and Tuba City, AZ These sites have been transferred to the DOE LTSM Program for oversight and monitoring Navajo UMTRA is coordinating with DOE the site transfer of the Monument Valley property to the DOE LTSM Program DOE and NN EPA personnel during the 2010

annual inspection discussing minor depression due to past core sampling activities. Navajo UMTRA Background & History, cont. Program staff performs quarterly and participates in the annual LTSM inspection

with the DOE LTSM Program The quarterly inspection allows frequent monitoring of the Navajo sites in support of the annual inspection Site inspection include the assessment of the disposal cell top and side slopes; existence of vegetation on cell; conditions of diversion and outflow channels; terrace and outlying site perimeter area and Navajo UMTRA Background and History, cont.

Condition of access road to the cell, fence repairs, entrance and perimeter signs, site markers, survey and boundary monuments, and erosion control markers Down gradient ground water seep locations away from the disposal cell property Ensure compliance to disposal cell

regulations and standards for long term maintenance SHIPROCK UMTRA SITE Shiprock Site

Walk-through assessment is performed to check for evidence of settling, slumping, erosion, animal burrowing and deep-rooted vegetation on the riprap covered top, side slopes and disturbed areas Check conditions and type of vegetation in channels Check for slope retreat and tension cracks near the escarpment Document new wind-blown sand near site fence line Inspect fence around and condition of the pond Completed radon / gamma radiation exposure

assessment of disposal cell cover in support of the 2000 DOE survey Mexican Hat UMTRA disposal cell Mexican Hat Site

Walk-through assessment is performed to check for evidence of settling, slumping, erosion, animal access and burrowing and deep-rooted vegetation (biointrusion) on the riprap covered top and side slopes Check conditions, document location and type of vegetation in the diversion and erosion channels Document erosion and trash build-up along the boundary fence line Document condition of boundary fence and evidence of trespass

BIOINTRUSION Mexican Hat Site, cont. Check condition of diversion ditches and disposal cell apron located on the southern edge of cell

Check property condition in the outlying areas for disturbance due to grazing & public recreational use Check condition of ground water seep locations down gradient to the disposal cell for surface water pathway exposure to general public and livestock TUBA CITY UMTRA SITE Tuba City Site

Walk-through assessment is performed to check evidence of settling, slumping, erosion, rock cover degradation, animal burrowing and deep-rooted vegetation on the riprap cover top and side slopes Document and evaluate impact of sand accumulation in the diversion channels

Conduct perimeter site monitoring of the fence line, monitoring wells, signs, monuments, site markers Document sand accumulation and wind erosion along boundary fence line Contact Information Website Address: www.aml.navajo.org www.lm.doe.gov