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Ms. Ann Kolata SBI070.400.0002 October 15, 2013 Page 4 defined. This task will begin with the advancement of temporary screens using direct -push technologies (e.g., a ST -15 Hydropunch) to a shallow depth (i.e., 26 to 30 feet below ground surface (bgs)) and a deeper depth of approximately 36 to 40 feet bgs at each of four (4) locations, subject to approval of these locations from the Client's Board of Public Works (BPW). The locations may be adjusted slightly in the field based on field observations such as utility locations, etc. Hull will work with the drilling subcontractor and the appropriate City and St. Joseph County authorities to arrange for access for the work and to clear utilities and to prepare appropriate permits for drilling in the right -of -way. Adjacent property owners will be notified by certified mail prior to the initiation of any drilling activities. Drill cuttings and sample purge and decontamination water will be containerized and placed at a location designated by the City. At each location where groundwater sampling is to be conducted, the borehole will initially be advanced to the deeper depth (i.e., between approximately 36 and 40 feet bgs), at which point the outer casing of the sampling system will be withdrawn to expose a four foot long stainless steel wire wrapped screen. Once the screen is exposed, Hull will measure the static water level and lower a decontaminated Waterro foot -valve sampling pump or peristaltic pump to purge the equivalent of five well volumes of water to develop the aquifer surrounding the screen. Following extraction of each well volume, Hull will measure pH, temperature and conductivity to demonstrate that representative groundwater is being sampled. In addition, Hull's representative will note if there is a visible sheen on the extracted water. After development, the temporary well will be allowed rest for approximately 20 minutes prior to sample collection. Following purging, Hull will collect groundwater samples that will be pumped through the Waterra or bladder pump tubing at a flow rate of less than 100 ml /min. Samples will be transferred directly into laboratory - preserved sample containers and placed on ice in a cooler. Following collection of each sample, Hull will retrieve and decontaminate the Waterra foot -valve pump by washing it with Alconox and water and rinsing it with deionized water. In addition, the sample tubing will be replaced between each sampling interval. The groundwater sample in the upper portion of the aquifer (i.e., between approximately 26 and 30 feet bgs) will be collected by withdrawing the screen to the appropriate depth and purging and collecting a groundwater sample as described above. The process for purging and collecting the relatively shallower groundwater sample will then be completed as described above. Between each of the sampling locations, the drilling rods and well screen will be decontaminated by washing with Alconox and water solution and rinsing with deionized water. Up to 13 groundwater samples (two samples at variable depths per borehole in the Arnold Street borings, plus one sample collected from approximately 25' bgs within the footprint of the former Oliver foundry) plus seven QA /QC samples, collected from the temporary boreholes using direct -push technologies, will be analyzed for VOCs. Two field blanks and two trip blanks will also be analyzed for VOCs. Results for the laboratory analyses will be requested to be reported by the laboratory within five business days. Pending laboratory results from the temporary sampling points, four deep and shallow nested monitoring wells will be installed off -Site in the vicinity of the Kroc Center and the Laurel Place Apartments (preferably within City right -of -way), to further evaluate the downgradient distribution of VOCs north of the Site. Following the receipt of laboratory results on the temporary sampling locations, up to three deep and shallow nested monitoring wells will be installed within the right -of -way of Arnold Street at locations approved by the City.