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A pilot-scale drip dispersal system (DDS) was installed at the Mines Park Test Site at Colorado School of Mines in Golden, CO. to research the benefits of this technology for wastewater treatment and reuse in a semi-arid environment. Two zones of the DDS have been in operation since November 2005. The two zones are individually operated to control hydraulic loading rates and disperse either 0.5 or 1.0 cm/d of domestic septic tank effluent (STE) into an Ascalon sandy loam soil 0.2-0.3 m below ground surface. Within each zone, one portion was landscaped with sod while another portion was allowed to naturally vegetate. After an initial few months of startup activities, routine operation commenced in March 2006. Since that time, the drip system has been monitored for operational stability, effluent distribution efficiency, and treatment performance, including a multi-component tracer test. Monitoring data have revealed that the drip system has reliably dispersed the STE applied. The spin disk filter unit was shown to have little effect on the composition of the STE delivered to the drip lines. Data from a tracer test and 3-D coring event revealed that STE moves preferentially along the drip tubing as it infiltrates into the native soil. The addition of STE to the shallow subsurface attenuates the natural variability of pH, water content, and inorganic nitrogen in the soil. In addition, fecal coliform bacteria levels adjacent to the drip lines were very low or non-detectable.