From: KENT Mavis D

Sent: Wed Jul 12 12:16:11 2006

To: 'Sarah Prowell'; 'Chris Kimmel'

Subject: Well Field Monitoring

Importance: Normal

Sarah and Chris, here is my take on the PBWW decision criteria:

TSA:

BOP-43(dg): change this to BOP-20(dg), since the development of lot 1 might eliminate BOP-43 anyway, keep MCL.

EMC-2(dg): keep this as is since it is the only well of the PBWW wells listed that has had detections

D-15(dg), PWB-2(lts): eliminate, but perhaps replace with PWB-1(lts) since there are actually low concentrations but make the criteria MCL instead of 1 ug/l.

SGA:

PWB-2(usg): eliminate

BOP-68(usg), BOP-44(usg), EMC-2(ust), PWB-1(usg): if we say there isn't a plume in the SGA is seems pointless to monitor it, on the other hand (as geologists are wont to say) if pumping is stopped in EW-20 then conditions would change (even though there is an expected upward gradient) so something should be monitored. Would this be done effectively by DEQ-3(usg) using MCL? I think 9 to 11 years of non detect at pretty low detection limits elsewhere in the SGA is comfort enough that the plume did not spread.

Let me know what you think. I am pretty busy tomorrow but would have some time before 10 am to talk. Otherwise I am out until Monday before 10 am then at meetings the rest of next week.

Mavis D. Kent

Cleanup & Emergency Response Section

DEQ Northwest Region - East Side Office

1550 NW Eastman Parkway, Suite 290

Gresham, Oregon 97030

503-667-8414 X55008

503-674-5148 Fax

kent.mavis.d@deq.state.or.us