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<br /> Thanks for your email of today to Gavin. We spent some time reviewing the data, so that we
<br /> could summarize this for you, confirm what has been decided and request guidance on some other
<br /> I
<br /> ssues.
<br /> To the best of our ability and based on the information in each of the letters and emails, here
<br /> goes :
<br /> All wells are to be sampled by low-flow protocol, because the 2/29/09 testing of the methods
<br /> showed no difference between them.
<br /> All wells to have DTW obtained quarterly to establish gw gradient and flow direction,
<br /> Rebound sampling to occur " after the first week" of October, 2009 and evaluation of results
<br /> to direct future of iSOC treatment on site.
<br /> And requested a new well, MW-9, due west of MW-8 and the fire station and south of the
<br /> most southerly remediation well, to confirm the lateral, cross-gradient extent of
<br /> contamination reported in MW-5B.
<br /> Lab Analyses (Well #, Frequency/Sampling Quarter, Analytical/ Date of Letter)
<br /> MW- 1 1Q (October , 5/13/09 letter) gas, BTEX ( 12/23/08),
<br /> MW-2 IQ (October , 5/13/09 letter) gas, BTEX ( 12/23/08)
<br /> MW-3 1Q (October, 5/13/09 letter) gas, BTEX (12/23/08)
<br /> MW-4 1Q (October, 5/13/09 letter) gas, BTEX (12/23/08)
<br /> MW-513 2Q (October, April, 5/13/09 letter) gas, BTEX (12/23/08), oxys and Lead scavengers
<br /> (12/23/08)9
<br /> MW-6 1Q (October and April, 5/13/09 letter) gas, BTEX (12/23/08)
<br /> MW-7 2Q (October, April, 5/13/09 letter) gas, BTEX ( 12/23/08), oxys and Lead scavengers
<br /> (12/23/08)5
<br /> MW- 8 2Q (October, April, 5/ 13/09 letter) gas, BTEX (12/23/08)
<br /> DPW- 1 1Q (October, 5/13/09 letter) gas, BTEX, oxys and Lead scavengers until contaminant
<br /> trends are established (2/17/09 letter).
<br /> AS- 1 2Q (October, April, 5/13/09 letter) gas, BTEX, oxys and Lead scavengers until
<br /> contaminant trends are established (2/17/09 letter) .
<br /> IW-3 one event (October 7/23/09 letter) gas, BTEX, oxys and Lead scavengers (these have not
<br /> been specified)
<br /> Questions :
<br /> Do you want MW-7 or MW-8 to have the oxys and lead scavengers?
<br /> What do you want on IW-3 ?
<br /> Should the wells be gauged 4 times a year?
<br /> How many events constitute an established contaminant trend?
<br /> Requests : Here are some more requests :
<br /> A) That all IW wells be sampled, but sample be put on hold. Then they would be analyzed or not,
<br /> based on sequential lab results, starting at IW-3 and the other Mws, stepping out from hot wells,
<br /> stopping at ND wells. The objective is to better delineate the gw plume at this juncture while the
<br /> remediation wells are not in use.
<br /> B) Complete depth discrete sampling in the sorbed phase soil contamination plume area shown in
<br /> the SCM. Based on the results from AS- 1 which is screened for 3 feet between 22 and 25 feet
<br /> bgs, we think that there is a trapped sorbed layer of contamination. To test this theory, we could
<br /> do depth discrete sampling at this zone, and the zone above, in other wells. So this would mean
<br /> 10/1 /2009
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