SUBSURFACE LANDFILL FIRE SUPPRESSION AND MONITORING
                        A Case Study at the Campbell Mountain Landfill, Penticton, British Columbia

Initial Monitoring Results.
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The temperatures recorded in the wells sited along the crest of the North Ravine, and near the composting operations (GMW98-1A, GMW98-5A and GMW98-8) as shown in figure1 (opens in new window), ranged from 18.8 degrees C. to 46.8 degrees C. The temperatures recorded at GMW98-1A, GNW98-5A and GMW98-6A are interpreted as background temperatures commonly found in landfills with a thickness of 20 metres or more. The lower temperatures in GMW98-8 reflected the fact that the waste is less than 10 metres thick at this point, and that the well is located near the edge of the landfill.

GMW98-1A, GMW98-5A and GMW98-6A also exhibited a common vertical temperature gradient. The highest temperatures (41.9 degrees C. to 46.8 degrees C.) occurred between 8 and 15 metres below surface, with temperatures decreasing towards both the surface and the native sub-surface.

The highest temperatures recorded in the North Ravine occurred in the "middle" wells (GMW98-2A, GMW98-3A and GMW98-7A). The highest temperatures recorded were 68.9 degrees C. (at 4 metre depth) in GMW98-3A and 52.1 degrees C. and 61.8 degrees C. (at 6.5 and 11.5 metres respectively) in GMW98-2A. A refuse fire should be suspected if landfill temperatures of 70 degrees C. or higher are present, although landfill fires can occur at lower temperatures (Marshall). The temperatures of 62 degrees C. to 69 degrees C. therefore have been interpreted as indicating the presence of a nearby refuse fire, although the wells themselves were not drilled directly into it.

The temperatures recorded in GMW98-4A were interpreted as indicating background conditions.

The results of the temperature monitoring program are visually summarized in a three dimensional graphic in Figure2. (opens in new window). Warm colors including red and orange are used to delineate locations where temperatures were elevated to levels indicative of possible proximity to landfill fires. Cool colors including blue and green indicate areas of normal landfill temperatures. The initial monitoring results clearly indicated elevated temperatures on the central portion of the North Ravine, in the vicinity of the collapsed feature that was noted at the surface.

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