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the c ombining o f F or-ward Landfill, w ith t he former A ustin R oad Landfill a nd (2) t he expansion of the new (combined) Forward Landfill. This design used a base aerial topographic map flown on October 6, 2000. To estimate the remaining airspace and associated site life for the JTD, Bryan A. Stirrat & Associates (BAS) personnel used a planimeter to estimate the remaining airspace "between" the October 6, 2000 topographic contours and the proposed design (base and final cover) contours. This remaining airspace was then projected mathematically to June 15, 2002. This June 15, 2002 then became the "starting point" mentioned above, which was used with a projected rate of future airspace consumption to estimate the remaining site life. In addition to the remaining airspace estimates prepared for the JTD, a second firm, Bullseye Design Services (Bullseye) has estimated remaining airspace for Forward Landfill for several years, each time a new aerial topographic map was prepared. A difference was noted between the Bullseye estimates and the JTD estimates. Initially, telephone conversations with Bullseye indicated that they did not fully understand existing and proposed conditions (e.g., what was soil, what was refuse, and what base liner grades and final grades were proposed for the combined, expanded landfill) at the .landfill. _.S-absequently, an attempt was made to resolve the discrepancy between the estimates and the Bullseye estimates. Initially, existing and proposed conditions were explained to Bullseye, but a noticeable discrepancy still remained. B asically, the Bullseye estimates were less than what one would expect, based on the JTD estimates. BAS reviewed Bullseye's estimates and concluded that Bullseye (1) had interpreted the design relative to existing conditions correctly and (2) had prepared their estimate correctly. In addition, a file search at BAS revealed that the drawings that had been planimetered originally were no longer available. (NOTE: The practice of destroying all preliminary, or draft, copies of a professional work product and keeping only the final version, released for use, is not uncommon. The planimetered drawings might have appeared to be draft versions of the drawings (Such drawings are frequently marked with colored pencils, or pens, to facilitate the planimetering.) and, thus, were destroyed accidentally. Another possibility is that the BAS employee who performed the planimetering, who is no longer employed by BAS, simply failed to file the drawings.) Therefore, a thorough review of the original estimate was not possible. Following this, BAS was asked to prepare a new estimate. This new BAS estimate was consistent with the Bullseye estimates. Conclusions Regarding Forward Landfill Site Life Several items in the above summary are particularly significant. 1. The"June 15, 2002"remaining airspace (or"starting point") presented in the JTD was not based on an aerial topographic map. It was a mathematical projection of an estimate based on an October 6, 2000 aerial topographic map. 2 MAY - 5