Sampling and analysis of radioactive liquid wastes and sludges in the Melton Valley and evaporator facility storage tanks at ORNL

Abstract

The sampling and analysis of the radio active liquid w_lstesi_indsludges in lilt' Mcllc_n Valley Storage Tanks (MVSTs), as well as two ol, the evapl_rator service tiicility storilgc, tanks _lt ORNL, are described, •Aqueous samples of the supernal lint liquid nnd compc)situ samples of the sludges were analyzed for major constituents, radionuclide's, tot_ll orgi_nic carbon, and metals listed as hazardous under the Resource Conserw_tion mad I,l.c_,covcry Act (RCRA). Liquid samples from five tanks and sludge samples from three i_lnks weru analyzed for organi_ compounds on the Environmental Protection Agency (EPA) "I'_lrgct Compound List. Estimates were made of the inventory of liquid _tnd sludge pta_musin the tanks. Descriptions of the sampling and analyticltl activities lind t_ihuliitions o['/h¢_ results are included, The report provides data in support of (1) the design t.3t"the t_l'Opc3sudWilstu Handling and Pack_tging Plant, (2) the Liquid Low-Level Waste Solidific_ltion Project, _lnd (3) research and development activities (R&D)activities in devl'loping wltste m_milgement alternatives.

Radiological assessment of worker doses during sludge mobilization and removal at the Melton Valley storage tanks

“…2.4). The sludges have been sampled on three ,occasions over the past ten years (Peretz et al 1986; Sears et al 1990; Ceo et al 1990). These reports.state that at least two tanks (W-27 and W-31) have hard sludges, and that the soft sludges in the tanks, after being mixed ultrasonically, varied in consistency from "prepared mustard" to "peanut butter."…”

“…However, samples can only be taken fiom each tank through the G-3 nozzle, and it is not known if t8e sludge samples are representative of sludges at other locations within each tank. Sears et al (1990) also.sampled the supernatant liquids (also referred to as supernates) in the tanks. Since additional liquid wastes have been added to the tanks since that time, the supernatant liquids in six of the tanks (W-24 through W-28 and W-31) were recently sampled again, and the preliminary "March 1996" data have been reported by Moore (1996).…”

“…In the study by Sears et al (1990), one or more samples of sludges and supernatant liquids were taken from the waste tanks, and exposure rates at contact with the unshielded samples were measured in the field. Exposure-rate measurements also were made on subsamples of the sludges after they had been dried overnight in a laboratory at 115°C.…”

“…In the study by Sears et al (1990), sludge and supernatant samples were collected from the waste storage tanks, and exposure rates for unshielded samples were measured in the field. To compare with the measurements, we have calculated the exposure rates using the analytical data on the samples from Sears et al (1990) and the preliminary "March 1996" data reported by Moore (1996 …”

“…To compare with the measurements, we have calculated the exposure rates using the analytical data on the samples from Sears et al (1990) and the preliminary "March 1996" data reported by Moore (1996 …”