Entech, Inc. retained Western Research Institute (WRI) to measure emissiqns from their Model TOS-80 thermal oxidation demonstration plant located at Anchorage, Alaska. The system,which has a nominal capacity of 28 tons per day of municipal solid waste (MSW) , consisted of a primary combustion/pyrolysis chamber where the waste was batch-loaded onto a grate. The MSW was loaded through the top of the primary chamber using conveyors without preparation other than a manual sort to remove large pieces such as wire rope. The contents of the primary chamber were ignited using natural gas as fuel. Once combustion was under way, the primary chamber was operated in an air-starved mode. The gases given off were incinerated in a secondary combustion chamber, which has provision for natural gas addition to maintain temperature. When the pyrolysis was near completion, the primary chamber was operated in an excess-air mode to incinerate the residual char. Much of the ash fell through the grate and was removed manually after burn completion. A typical burn excluding ash cooldown lasted about 12 to 14 hours. The ash could also have been allowed to accumulate between burns, and then removed after a series of burns. This was done for burns 5 and 6. A total of nine burns were completed during this test series. The burns were performed on alternate days starting on April 20 and ending on May 8, 1993. A listing of the burns is in Table 1. For each burn, WRI completed three particulate emission measurements (denoted particulate A, B, and e), three HCl emission measurements, one metals/mercury measurement, and one organic measurement. Results of emission measurements are presented in Appendix A. Particulate A was collected near the start of the burn;sampling about 15 minutes after the start of combustion in the primary chamber. Particulate B was collected near mid burn; beginning about 3 to 4 hours after the start of combustion in the primary chamber. Particulate e was collected approximately 8 hours after the start of combustion in the primary chamber. The times of sampling are noted on the data sheets (Appendix B). Following the burn, samples of the ash were collected for the U.S. Environmental Protection Agency's (EPA) Toxicity Characteristic Leaching Procedure tests after the remaining ash cooled.