State of Oregon

Department of Environmental Quality       Memorandum

_____________________________________________________________________________________

Date:    July 5, 2005

To:    Steve Fortuna, Tim Spencer, NWR

From:    Bob Schwarz

   DEQ Cleanup Program

Subject:  Santosh Landfill, ECSI # 1383; Summer 2005 scope of work for Hart Crowser

Following is a summary of what I believe we agreed to include in the next round of sampling at Santosh Landfill. For your review. Thanks.

1.  Soil sampling

a)  Collect ten background soil samples at locations of similar geology and in areas near but unaffected by landfill and other human activities.

b)  Analyze each soil sample for all metals previously analyzed that have exceeded screening levels.

2.  Metals in surface water and groundwater

a)  Include both total and dissolved metals this time.

3.  VOCs in surface water and sediment

a)  Include VOCs this round because some VOCs were detected in groundwater.

4.  Drop TPH - TPH concentrations found to date are not significant and do not provide much useful information for risk assessment.

5.  Chromium: Sample groundwater and surface water for Cr6 in addition to total chromium

6.  Landfill gas monitoring

a)  Provide design and locations for landfill gas wells. (DEQ task?)

7.  Seep management

a)  Proceed with interim action for seep (awaiting final tech memo from Hart Crowser, which we will then submit to DEQ managers for approval to proceed with interim action).

8.  Sampling locations

a)  Groundwater: Same ten wells as in April 2004

b)  Groundwater in three transects (We should be able to collect sample using a drive point since groundwater should be at or near the surface):

i)  First transect: Four points roughly 200 feet apart starting at toe of slope by MW-1 and heading northwest.

ii)  Second transect: Four points roughly 200 feet apart starting at toe of slope about 400 feet northeast of MW-1. Transect is parallel to first transect.

iii)  Third transect: Three points starting at toe of slope by seep and heading to SS-02

c)  Surface water and sediment in Scappoose Creek: SS/SW-01, 02, 03, 08 and 09 (two new locations in creek further downgradient than SS-01)

d)  Surface water/sediment in slough as before (SS/SW-05)

9.  Sampling analytes: A table somewhat like the following would be good to include in the work plan to provide, at a glance, a sense of what analytes will be included for what matrices: