Improvements to the RV Waste-transfer Station Design to Reduce Contaminated Storm Runoff

Mammoth Cave in Central Kentucky is the world’s longest cave system and has been designated an international biosphere. It has unique organisms that live in the cave system and they are dependant upon high quality water supplied through rain recharge. We have documented quaternary ammonia compounds (QAC) levels ranging from 0.2 to 22 mg/L in storm fl ow, as well as, other chemicals coming from the RV waste-transfer station. The objective of this project was to re-design the drain system around the dump station to prevent spillage from washing down into the cave. The first design feature is a v-trench to catch storm runoff and redirect it into the sanitary sewer. The second feature is a gently elevated barrier that will impede the fl ow of runoff from the impacted area. The designs presented in this paper incorporate both features

Evaluation of Stormwater Filters at Mammoth Cave National Park, Kentucky, 2011-12

Studies in the 1970s found potentially toxic levels of metals entering Mammoth Cave’s underground streams through storm recharge. Additional studies confirmed that stormwater from parking lots and buildings fl owed rapidly into critical cave habitats. The Park’s management responded to these findings by installing storm runoff filter systems on the most heavily used parking lots in 2001. The Park entered an agreement (2010-12) with Tennessee State University, the USGS, and WKU-Mammoth Cave International Center for Science and Learning to evaluate the filter systems to determine if they were removing hazardous compounds from stormwater runoff . The objective of this study was to evaluate stormwater filters before and after replacing 2-year-old ZPG cartridge filters. The study focused on the first-flush runoff waters during the storms. The filters were not effective at removing quaternary ammonia compounds (QACs), and moderately eff ective at removing zinc and copper. The filters were very effective at removing diesel-range aromatic ring compounds (fuels). Regression analyses were used to evaluate trends between parking lot size and filter efficiency. The efficiency of the filters to remove fuels improved with basin size. The efficiency to remove QACs decreased with basin size. Basin size did not appear to have any correlation to zinc or copper removal efficiency. Human activity, such as construction, probably played a role in the storm-water chemistry and the efficacy of the filters to remove certain contaminants