Radioactive and organic solvent waste was disposed into unlined trenches at Site 1 from 1971 through 1980. The total volume of waste disposed was estimated to be 40 cubic yards (yd3) buried with a total radioactivity of 250 millicuries (mCi). A Supplemental Preliminary Assessment was conducted at Site 1 in 1995 by Environmental Science and Engineering, Inc. Six wells were installed, sampled and analyzed for volatile organic compounds. All analysis results were below detection limits. CABRERA conducted a removal action at Site 1 in 2002. The impacted media included soil and groundwater. Both radionuclides of potential concern (ROPCs) and chemicals of potential concern (COPCs) were identified within the former waste burial pits. Evidence of solvent staining on the north wall of the trench and a review of the data from their 1996 preliminary assessment indicated that groundwater flow direction was to the northwest (at least on the measured dates), where no downgradient wells existed to assess possible groundwater contaminant migration. Six [6] new monitoring wells were installed, and the initial groundwater sampling event including existing and newly installed monitoring wells. Two additional sampling events were conducted to supplements existing groundwater analytical data for the purpose of refining the conceptual site model for USDA.. The groundwater flow direction was complex at the May 2004 measurement; both a southwestward and a northeastward component were calculated. Observation of soils during completion of the new borings supports previously observed conditions; soils at the site consist largely of dense sandy silt and clay with highly localized variation in sand content. None of the previously identified COPCs or ROPCs were identified above method detection limits (or background levels for ROPCs), however, 1,4 -dioxane was reported (and confirmed). This compound was detected in ten of the eleven wells sampled at concentrations ranging from less than 2 µg/L to 1,900 µg/L. There is no federal drinking water standard for 1,4-dioxane, however, there is a USEPA advisory level for 1,4-dioxane of 3 µg/L. A MCL standard for 1,4-dioxane has not been established by the State of Iowa but a HAL does exist at 9 ug/L..