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7.3.12 The following Sections detail how to add the appropriate amount of extraction fluid to the solid material within the ZHE and agitation of the ZHE vessel . Extraction fluid #1 is used in all cases (See Section 5.7) . 7.3.12.1 With the ZHE in the vertical position, attach a line from the extraction fluid reservoir to the liquid in- let/outlet valve. The line used shall contain fresh extraction fluid and should be preflushed with fluid to eliminate any air pockets in the line. Release gas pressure on the ZHE piston (from the gas inlet/outlet valve) , open the liquid inlet/outlet valve, and begin transferring extraction fluid (by pumping or similar means) into the ZHE. Continue pumping extraction fluid into the ZHE until the appropriate amount of fluid has been introduced into the device. 7.3.12.2 After the extraction fluid has been added, immediately close the liquid inlet/outlet valve and disconnect the extraction fluid line. Check the ZHE to ensure that all valves are in their closed positions . Manually rotate the device in an end-over-end fashion 2 or 3 times. Reposition the ZHE in the vertical position with the liquid inlet/outlet valve on top. Pressurize the ZHE to 5-10 psi (if necessary) and slowly open the liquid inlet/outlet valve to bleed out any headspace (into a hood) that may have been introduced due to the addition of extraction fluid. This bleeding shall be done quickly and shall be stopped at the first appearance of liquid from the valve. Re-pressurize the ZHE with 5-10 psi and check all ZHE fittings to ensure that they are closed. 7.3.12.3 Place the ZHE in the rotary agitation appara- tus (if it is not already there) and rotate at 30 + 2 rpm for 18 + 2 hours. Ambient temperature (i .e. , temperature of room in which extraction occurs) shall be maintained at 23 + 2 °C during agita- tion. 7.3.13 Following the 18 + 2 hour agitation period, check the pressure behind the ZHE piston by quickly opening and closing the gas inlet/outlet valve and noting the escape of gas. If the pressure has not been maintained (i .e. , no gas release observed) , the device is leaking. Check the ZHE for leaking as specified in Section 4.2. 1 , and perform the extraction again with a new sample of waste. If the pressure within the device has been maintained, the material in the extractor vessel is once again separated into its component liquid and solid phases . If the waste contained an initial liquid phase, the liquid may be filtered directly into the same filtrate collection container (i .e. , TEDLAR® bag) holding the initial liquid phase of the waste. A separate filtrate collection container must be used if combining would create multiple phases, or there is not enough volume left within the filtrate collection container. Filter through the glass fiber filter, using the ZHE device as discussed in Section 7.3.9. All extract shall be filtered and collected if the CD-ROM 1311- 18 Revision 0 July 1992