State of Oregon

Department of Environmental Quality       Memorandum

_____________________________________________________________________________________

Date:    July 12, 2011

To:    Scott Kranz, AMEC

Copies:  Debbie Bailey, DEQ

   Paul Seidel, DEQ

   Bob Williams, DEQ

   Tim Spencer, DEQ

   Charlie Schwarz, ODOT

   Mark Ader, EPA

   Ken Itel, Clackamas County

From:    Bob Schwarz, DEQ

Subject:  ODOT - Sunrise Corridor Project, ECSI # 5538; Sampling and Analysis      Plan for Camp Withycombe soil

Following are our comments regarding the Sampling and Analysis Plan, Camp Withycombe. This document was prepared by AMEC Earth & Environmental, and was received by email on June 13, 2011.

1.  Soil handling in the field. The standard operating procedure (Sampling-SOP-0001, procedure step 13) states that extra soil should be placed back in the hole where it was collected. This implies that sample soil will be handled in some way in the field. Please note that the soil sample should be placed in the resealable plastic bag and that subsequent management of the entire soil sample should be performed in the lab.

2.  Samples for VOCs. As we discussed by phone, samples for VOC analysis must not be dried, ground, or sieved.

3.  Proximity of primary, duplicate and triplicate samples. How closely spaced are the primary, duplicate and triplicate samples in the southern decision unit?

4.  Allowable contaminant concentrations. Your plan proposes that the material be allowed for disposal within the Sunrise Corridor construction project if contaminant concentrations do not exceed DEQ risk-based concentrations (RBCs) for construction workers (QAPP Worksheet#15). As noted in my June 30, 2011 email to you, the plan should evaluate whether these levels are protective, taking into account:

•  Depth to groundwater,

•  Distance to surface water,

•  Beneficial uses of groundwater and surface water,

•  Potential for contaminants to leach to groundwater or migrate to surface water, considering underlying soil type, groundwater flow direction and rate, grading and covering of the contaminated soil.

Since then, we received EPA’s July 6 letter to you, in which they require that soil contaminant concentrations not exceed soil cleanup levels specified in the Record of Decision for the Northwest Pipe & Casing site. For contaminants other than the 11 listed in the Record of Decision, EPA requires that contaminant concentrations not exceed DEQ Clean Fill concentrations. I discussed this by phone today with Mark Ader at EPA. Mark noted that the action levels identified in the Record of Decision are based primarily on preventing leaching of contaminants to groundwater.

If you would like to discuss any of these issues, I would be happy to arrange a conference call with DEQ, EPA and AMEC.