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<br />..... <br />en <br />c,.J1 <br />co <br /> <br />2 <br />(O.003 inch openlng) <br /> <br />In the pro~osed Tasca II design2 the processed shale <br /> <br />is moisturized wit~ waste~ater, t:anspor~ed to the disposal site and compacted <br />to a density of about 90 ~ounds of drj spent shale per cubic foot. The compacted <br />shale will have an in-place moisture content of about 13 percent. The adcition <br />of the water leads to cementation of the shale after compaction, producing a <br />substance which apparently freezes in the moisture that was added and which is <br />effectively impermeable and resists percolation so that soluble salts cannot <br />be leached out. ~he water adced to the spent shale contains the dirty water <br />from the retorting and upgrading operations# blowCown water from ion e~change <br />treatment, blowdown water from the cooli~9 tower and ather blowdown ~,d was~ewa~er5. <br />Treatment is required to remove odorous, volatile components from the dirty <br />process water be~ore :eing usee to moisturize the spent shale. All of the <br />wastewaters generate~ in the ~ine-plant complax are not sufficient to provide <br />the prope~ ~oisture conte~t for disposal and acditional water from the =iver <br />~us~ be added. L~ addition, rive~ ~ater is provided for revegetation. As a <br />result, ~~e wate= ma:.agement scheme fo~ ~~e Tosco II process is net premised <br />upon the t=ea~en~, recycling, and reuse of wastewaters wi~~in the plant, <br />since all of the wastewater and more is required to mois~urize ~he spent s~al~ <br />:or dispcsal. The only major treatment ~~at woul~ be =equired is to re~ove <br />odorous, volatile substances, such as ~onia and hydrogen sulfide. This is <br />s~ancard practice in =efineries and is done as par~ of the normal upgradi~g <br />operaticn. After co~paction, additional water will be used to cont~ol fugitive <br />dust and to establish vegetative cover. <br /> <br />In the paraho processes, the spent shale ~onsists of lumps about <br /> <br />1 1/2 inch in size9. The Paraho design for ~~e dis~o9al of the spent <br /> <br />3/8 to <br />. , 9 <br />3na_e <br /> <br />involves lining a valley ~it~ a heavy compacted imper~ious layer of retor~ed <br />shale. As a result of adding about 20 percent by weight of water to the spent <br />shale and then compacting it, the shale cements up and the layer is made <br />impermeable. The remainder of the retorted shale is deposited i~to the lined <br />basin and is compacted but not wetted down except for controlling dust ~~d for <br />vegetation. Less t~an one percent of ~~e total 701urne of spent shale ~oulc ~e <br />wetted down, substantially reducing ~~e water requirements for spent shale <br />disposal for the Paraho process in comparison to the Tosca II process. However, <br /> <br />-, <br />o~ <br />