Tank decontamination

All equipment should be cleaned and decontaminated (such as, pumps, tank loading areas, storage areas). ... 

If ABC Co. materials were stored m an underground tank, the tank should be cleaned and examined for possible leakage. If leakage is indicated, the area must be decontaminated. ... 

M17 Lightweight Decontamination System (LDS) The M17 is a portable pump and water-heating unit for producing hot water and steam. The system incorporates a 1,580-gallon collapsible water tank, two wand assemblies, connecting hoses, and a shower rail. It is issued to Army battalion-size units and to chemical decontamination companies and battalions. 

The PRH hydrolysate is discharged to a stirred tank, where the hydrolysis of agent is completed. Air is drawn through the PRH to remove volatile materials, and the gaseous effluent is passed through a CATOX, scrubber, and carbon filters prior to release to the plant s HVAC system. The solids, consisting of the washed munitions parts, go into the HDC that treats metal parts from the projectile agent removal system (Step 16), where they are decontaminated to a 5X level. 

In Step 9 of the GATS process, the dry, size-reduced dunnage materials and nonprocess wastes from Step 2 are slurried with energetics hydrolysate in preparation for feeding to one of the SCWO reactors. Following the removal of precipitated aluminum compounds by filtration in Step 7, the energetics hydrolysate is transferred to one of two hydropulpers. Spent decontamination solution used in various decontamination operations in the plant also goes to the hydropulper tanks. 

The vendor claims that Houdini is qualified for a number of waste remediation applications. Uses for Houdini include mechanical waste retrieval, hot cell decommissioning, tank decontamination, material containerization, wall scabbling, tank inspection, pipeline cleaning and repair, and ship and barge cleaning. 

The work on hi level waste solidification has led to applications of the same materials to other areas of waste management. These include decontamination of defense wastes currently in tank storage at Richland, WA, selective separation of Cs for beneficial uses, and development of a process flowsheet for conversion of Zircaloy fuel cladding hulls to sodium zirconate for use in waste stabilization. Each is briefly described below. 

CeH5.CH2(CH3)2.N(C16H33)Cl. A quaternary ammonium halide recommended by McDonatd(Ref 2) as satisfactory for the decontamination of waters coatg dissolved expl wastes. This, or other halide salts, can be added to a tank along with the waste water the expl material settles as an insol addn compd Refs l)Beil- not found 2)L.McDonald,USP 2647084(1953) CA 47,10853(1953)... 

The Neutralization Module accepts the ton container contents from the TCC module and destroys the agent batchwise through hydrolysis with water followed by caustic addition. The Neutralization Module consists of three units, each located inside a Containment Level A toxic cubicle. There are two HD Reactors and one TCC Effluent Tank in each of the three neutralization units. In each neutralization unit, drained agent held in the Agent Holding Tank is processed in batch neutralization reactions. The rinse and spray water from the TCC Module and spent decontamination solution are stored in the TCC Effluent Tank and process in separate batch reactions. In the neutralization reaction HD reacts with water to yield the principal hydrolysis products of thiodiglycol and hydrochloric acid. After the hydrolysis is complete and sample analysis results confirm the destruction of HD, 18 percent sodium hydroxide is added to the reactor to raise pH in order to increase the hydrolysate biodegradability. The hydrolysate is then pumped to the Hydrolysate Tank in the VOC Treatment Module. 

In addition, nonprocess air emissions are produced by three boilers, two diesel-driven auxiliary generators, a laboratory filter vent, the medical decontamination area, and a vent from the sodium bicarbonate storage tank. 

The CSSX process flowsheet for the decontamination of high-level waste was demonstrated in a 33-stage, 2-cm contactor apparatus at the Savannah River National Laboratory (formerly the Savannah River Technology Center).107 Simulated SRS average waste, simulated Tank 37H/44F composite waste, and actual Tank 37H/44F composite high-level waste were processed in three tests lasting 6,12, and 48 hours, respectively. 

Once the actual extraction-section aqueous feed is started, the process should be close to steady state after three residence times of the fluid have passed through the contactor stages. This action will typically take 15 to 30 min. If the above startup procedure is used, the decontamination factor for the extraction section will always be greater than the desired value, even during startup. Once steady-state operation is reached, the process is easy to control. The operator needs to check that the required feed flow rates are maintained, that the feed in each feed tank is appropriate, and that the rotors are spinning at the proper speed. Also, the feed tanks need to be monitored to avoid them running dry, and the effluent tanks need to be monitored for overflow. In plant operation, these tasks are usually automated. 

To document pre- and post-decontamination conditions of manmade structures (buildings, storage tanks, pipes)... 

Shut-down. When the end-of-feed condition occurs for 1AAF, 2AAF or 3AAF, the feed-line to the "high active" feed pump is switched over to the "inactive" feed tank, which can contain simulated HLLW solution, but more normally only HN0 of the appropriate concentration. This solution is used until most of the equipment has been roughly decontaminated. Then all feed-pumps and mixer-settlers are shut off. The mixer-motor units and level transducers are removed from the batteries and the mixer-settlers emptied from solution using a hose and pump attached to a waste tank. 

At PBCDF and TOCDF, if the chemical agent concentration is below 20 ppb for GB, 20 ppb for VX, or 200 ppb for HD, it may be shipped for off-site disposal (UDEQ, 2004 ADEQ, 2006). At PBCDF, if the chemical agent concentration is equal to or above the WCF, additional decontamination solution will be added to the tank, the contents of the tank will be mixed, and another sample will be analyzed for chemical agent. Also, off-site management must ensure that the SDS is directly fed into an incinerator from either the tanker truck or tanks dedicated to storing only this waste stream (ADEQ, 2006). 

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