Scope of Work for Wells 4s and 4i and Lemon Lane, February, 2002
Scope of Work for Sampling/Pump Test of Well 4s at Lemon Lane
Goal of the test is to determine if any high levels of PCBs exist near well 4S and
to determine the well's short term water production rate.
Preliminary Set-ups
Ensure that both of the water level probes and the conductivity meter are
functioning properly.
Measure current depth to bottom and compare to records.
Decontaminate 2" Redi-Flo submersible pump.
Install pump and test operability.
Assemble standard Groundwater sampling equipment, including truck bed
mounted 500-gallon purge water tank.
On morning of event take round of water levels in wells 21, 41, 6, 00-300A,
and NN-300A.
Set transducers in wells (21, 6 and NN300A) to 5-minute intervals.
Install temporary level platform beside 4s on which to put graduated carboy.
Operation of Sampling Event/Pump Test
- Begin pumping with submersible pump recording start time.
- Measure drawdown in pumping well. Measure pumping rate by discharging
into graduated 5-gallon carboy.
- Take temperature and conductivity readings every 5 minutes.
- Take PCB and TSS samples every 15 minutes. Include duplicate sample,
matrix spike, and field blank.
- Adjust pumping rate to a maximum without letting the pump go dry. The
desire is to pump at the max rate without going dry. If a sustained pumping
rate can be established without well going dry, continue test for 1 hour. If well
goes dry, record stop time and proceed with Recovery Test Procedure
described below.
- If the well does not go dry and after pumping for 1 hour, measure the water
level by hand in well 00300A.
- Turn off the pump after recording the water level in well 00300A.
Recovery Test Procedure
- Record start of recovery as To (same as stop time above).
- Wait a total of 15 minutes*. At T,5, resume pumping at low rate. Pump until
dry again. Shut off pump and record dry time as Td for cycle 1.
- Measure water volume in carboy, and dump into truck tank.
- At Tan, resume pumping and repeat recovery procedure. Record new Td for
cycle 2.
- Continue pumping and recovery cycles on 15-minute intervals until time Tee,
(beginning of what would be 4th pumping cycle, which is the end of test.
- The volume of water collected during each 1 5-minute cycle must be recorded
separately.
- Collect water samples at To, T,5, T30, T45, and T60 for PCBs and TSS.
Measure and record conductivity and temperatures.
*These times may have to be adjusted based on actual recovery of the well.
Part of the objective, though, is to complete this sampling event in a half working
day.
Post-samulina Activities
- Prepare samples for Heritage pickup.
- Download transducers, and re-set to hourly.
- Take purge water to Neals Landfill and dump into backwash storage tank
after receiving PCB results from Heritage.
- Provide copy of field notes and datalogger data to Mike McCann.
Scope of Work for Sampling/Pump Test of Well 41
Goal of the test is to determine if the drawdown and PCB levels during a short
term pump test would be significantly different than found in the summer 2001
tests.
Preliminary Pump Test Precarations
- Set-up 2500 gal. poly tank.
- Install pump and test operability.
- Assemble Groundwater sampling equipment.
- Ensure both water level probes and the conductivity probe are functioning
properly
- On morning of event take round of water levels in wells MOO-1 D, MW-1S, NN-
12A, 00-125A, 00-300A, 00-587A.
- Set transducers in wells MW-21, MOO-6, and NN-300A to 5-minute intervals,
and take hand levels.
- Arrange rush sample pick-up and analysis with Heritage.
Operation of Sampling Even/Pump Test
- Begin pumping, recording start time.
- One person will need to measure drawdown in pumping well and record
pumping rate. Pumping rate needs to be 10-12 gpm.
- Two people will need to take rounds of water levels.
- Take temperature and conductivity readings every 15 minutes.
- Take PCB and TSS samples every 15 minutes. Include duplicate sample,
matrix spike, and held blank.
- Take hand measurements in shallow wells at 30 minutes and at 60 minutes,
just before pump is turned off.
- Recovery in the pumping well should be measured for first hour after
pumping.
Post-sampling Activities
- Prepare samples for Heritage pickup.
- Download transducers, and re-set to hourly.
- Obtain PCB results from Heritage, and dispose of water at above ground
settling tank at Neal's Landfill spring treatment plant if less than 1 Oppb. If the
water is considerably more contaminated, then place a tank heater in the tank
and maintain the contents above freezing until a treatment trailer can be
mobilized to treat the water.
- Provide copy of field notes and datalogger data to Mike McCann.
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