Helotes Mulch Fire 2006 Tracing Groundwater Flow Using Natural Fluorescent Materials

Author Steve Johnson
Year 2018
Description With approximately 21 million gallons of water (LFCI, 2011) having been trained on the debris pile, the Helotes mulch fire effectively became a tracer test of huge proportions. It provided an opportunity for us to study the karst-related flow characteristics of the Edwards and Trinity aquifers. The fire-fighting water mobilized naturally fluorescing woody material and products of combustion that could be measured in groundwater using conventional fluorescence spectroscopy. Results revealed many of the characteristics of karst in both aquifers.
Report Number 18-03
Publisher Edwards Aquifer Authority
Location Helotes, Edwards Aquifer, Trinity Aquifer, Helotes Creek
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On the evening of December 25, 2006, an 80-foot high debris pile located in Helotes, Texas, caught fire as shown in Figure 1. The debris consisted of brush, trees, and other materials from area developers that had been converted to mulch over several years and stored until it reached approximately 400 feet (ft) long and 225 ft wide. After applying millions of gallons of water onto the pile, the fire was finally extinguished on March 28, 2007.