Area C, north of Pajarito Road near TA-50, became inactive April 8, 1974. Its history of use covers 26 years. There are seven pits within the area, one of which was reserved exclusively for the disposal of non-radioactive hazardous chemical wastes and 108 shafts; none of which are greater than 1m (3ft) in diameter and 7.6m (25ft) deep. Area C is the first burial ground for which detailed records were kept. Few Studies related to environmental monitoring have been conducted in Area C.
The history of Area C extends from may 7, 1948, the date the first pit was started, through April 18, 1974, the date the last shaft was filled and plugged with concrete. It is sometimes felt that the the last routine radioactive contaminated waste placed in area C, December 1958, marks the closing of area C and the opening of Area G. Neither idea is true. Area G pits had received non routine radioactive waste before that date and area C pits continued to receive non routine radioactive contained waste until Pit 6 was filled august 959 and Pit 5 was filled November or December 1964. Since quarterly and annual reports on solid radioactive waste disposal fail to mention Area C after 1968, it can be assumed that the area was not in regular use pats that time. The plugins of the last area C shaft, shaft 89, On April 1974, marked the formal closing of the area.
Type of Waste
During the pit history of Area C, hazardous chemicals and unconfined classified materials were buried with radioactive contaminated materials.
Hazardous Chemical Area in Area C
As pit use was phasing out in area C and beginning in area G, the idea of separate disposal for hazardous nonradioactive chemicals (which were responsible through the years for many fires in the disposal area) was accepted.
Potential environmental impacts:
Lies near Ten-Site Canyon New Mexico Environment Department's (NMED) Hazardous and Radioactive Material Bureau (HRMB) ranks this MDA as an area with a high probability of contaminant mobilization and a moderate to high potential of release to the groundwater.