Scope of Work for Flood Test of LF-6-8"

• Flush residual Fluorescein out of LF-6 area in preparation for other tracer tests.
• Determine if and when the flood pulse reaches the phreatic zone.
• Determine if flushed water induces a dye and PCB response at IC spring

Set up and Preparation

• Review weather and ensure no rain predicted for the test period (until at least 12 hours after predicted dye arrival time). Note, the test is also not to be done immediately after a large storm event. Spring flow at IC Spring should generally be less than 300 gpm before starting the test.
• Obtain flow from IC STF to estimate travel times.
• Place additional dataloggers in NN-12, NN-300A (Troll 8000), and KK-112 (dataloggers already in MW-21 and MW-6). On morning of test set logging interval to 5 minutes.
• Take hand measurements in MW-15.
• Take background fluorescent samples. Analyze samples on both filter fluorometer and SSFP. Samples should be taken at:
  • Illinois Central Spring
  • LF-6-8"
  • MW4s
  • 00-370
  • NN-300
  • 00-300
  • 00-300A
• Hook up fire hose to fire hydrant on Gray Street with flow meter and extend line to LF-6-3".
• Start auto samplers at Illinois Central Spring on hourly interval.

Flood Test

• Turn on water at fire hydrant and flush 1000 gallons into LF-6-8". Adjust inflow rate so water does not back up in riser.
• After flushing 1000 gallons, check LF-6-8" for visible dye, take a sample and run on the fluorometer, and determine if additional water needs to be flushed. It is desired to have no visible dye left in LF6 after the flush.
• Monitor water levels by hand in MW-15 at 15 minute intervals for first hour and 60 minute intervals for 8 hours after start of test.
• Sample monitoring wells on 60 minute intervals for 10 hours after start of test.
• Field conductivities and temperature will also be taken for every spring sample in the field.
• Ten minute monitoring at IC Spring continues until:
  • Visible dye pulse passes through the emergence
  • And Conductivity at IC Spring passes through the minimum and begin to increase.
• After 10 min. monitoring ceases, auto samplers are set up for hourly sampling for the receding limb at IC Spring. Samples for dye analysis will be pipetted from the 500 ml autosample. Sample the wells on a 15 minute interval beginning after dye injection and continue until visible dye is observed in both wells or until visible dye is seen at IC Spring for up to 2 hours (or consult with test supervisor). When sampling the wells be sure to hang the bailer in the well above the water level and empty between sample intervals. The well samples will also be sampled for conductivity in the field.

Dye Analysis and PCB Sample Selection

• Dye and PCB samples are taken to office warehouse, where PCB samples are refrigerated. Dye samples are labeled with sequential dye number beginning with DT9000. Dye samples are prepared for dye analysis according to SOP and dye analysis is performed with fluorometer. Dye results are plotted and PCB samples are selected to coincide with dye pulse curve.
• PCB samples are labeled with LL number and submitted to Heritage lab. Flow hydrograph is obtained from IC STP and receding limb sampling is determined.
• Auto samplers are down loaded on 12 hour schedule and samples labeled and submitted to Heritage lab.