08/02/06 Sigler/Work Plan Requestpp -
Montana Department of �p
ENvmomvffiNTALQUAUTY Brian Schweitzer, Governor
P.O, Box 200901 • .Helena, MT 59620-0901 • (406) 444-2544 • www,ded.mt.gov
August 2, 2006
City of Kalispell
Susan Moyer
P.O. Box 1997
Kalispell, MT 59903
Subject: Work Plan Request for Monitoring Well Installation and Quarterly
Groundwater Monitoring at the Former National Guard Armory, 1840
Highway 93-South, Kalispell, MT; Facility -ID##15-13373, Release ##4494.
Dear Ms. Moyer:
The Department of Environmental Quality (DEQ) Petroleum Release Section (PRS) has reviewed the
30-Day Release Report, the Phase I, and the Revised Phase II Environmental Site Assessments
(ESA) for the facility referenced above. The reports indicate that six groundwater monitoring wells
were installed after laboratory analytical results from previous borings indicated soil and
groundwater had been impacted by petroleum hydrocarbons. The Revised phase II ESA states all six
wells have recently been abandoned. Additional soil borings were completed in the vicinity of MW-
6 as it was the only hydrocarbon impacted well. It is assumed the source of the contamination is fxom
a former underground storage tank that was removed in 1991, which was located near M'trJ'-6.
The scope of the corrective action work plan required is generally specified in CAP_MR-01
(http://w w.deq.state.mt.us/LUST/Te,chGuidDocs/techguidlist.asp) and must address the following
specific site needs:
Excavate as much of the hydrocarbon impacted soil from the areas of MW -6 and SB-12. This
would include impacted soil at and below the water table. Provided the area of concern is as
small as it appears your consultant should find a way to contain the liquid excavation,
Something as simple as a bermed area with a visqueen base would suffice until the water has
evaporated. Once the soil is sufficiently dry it can be hauled to a landfill. Another method
would be to have a vac -truck on -site during the excavation to remove excess water from the
excavation. Does the City of Kalispell own property that could be used as a one time
Iandfarin for the soil? This would save on hauling costs and expenses asso eiated with the
landfill. The drawback is the time it takes the soil to remediate to DEQ standards. Does the
Kalispell landfill have drying beds?
2. Your consultant has suggested air sparging as a rernediation tool. The DEQ does not
recommend or approve this method of soil/groundwater remediation.
3. Collect discreet soil samples from the sidewalls and bottom of the excavation. Do not
composite the samples.
Enforcement Division - Permitting & Compilnnce Division - Planning, Prevention & wssL4cance Division • Rcmediation Division
Page 2
FID#15-13373/4494
.August 2, 2006
4. Have the soil samples analyzed for volatile petroleum hydrocarbons (VPH).
5_ The plume is not delineated to the north. Soil boring-2 (0-2) indicates 7.3 parts per billion
(ppb) Benzene in groundwater. DEQ Risk Based Screening Levels for Benzene in
groundwater is 5.0 ppb. You are required to define the horizontal extent of the hydrocarbon
plume to the North of the facility. No soil or water samples were obtained from SB-1 and
SB-3 to the left and right of SB-2 respectively. ,
6. InstalI a minimum of three groundwater monitoring wells. Screen the wells from three feet
below ground surface to 13 feet bgs.
7. Collect groundwater on a quarterly basis for one year, and submit the reports on a quarterly
frequency. -- _.
Have your consultant provide separate tables for the soil and groundwater analytical data.
Include the sample depth for the soil samples and static water levels on the groundwater
table.
9. Provide a site map that includes all sample locations with analytical results.
Have your consultant contact this office to discuss the work plan and the hours required to complete
it. By August 15, 2006 have your consultant submit to this office a work plan for the above Scope of
work,
The CAP should include itemized costs and a description of the tasks proposed, DEQ requests your
consultant to obtain three bids for all non-professional environmental subcontracted services. Costs
to conduct the drilling should be submitted as unit bids. Three (3) bids are requested for all non-
professional environmental services, including but not limited to, drilling services, construction
services, electrical services, etc. Laboratory analytical services are excluded from obtaining 3 rids,
All bids will need to be submitted with the CAP. Implementation of the CAP can begin after the
work items and costs have been reviewed and approved the DEQ-PRS and the Petroleum Tank
Release Compensation Board (PTRCB).
You must keep this office informed about the progress of work conducted at this site. If you have
any questions in this matter, please contact me at the DEQ-PRS (406) 755-8985, ext.105.
Sincerely,
Marcile Sigler
Environmental Specialist
1tr554.ms
Attachments Unit Cost Worksheet
cc: Tom Kandt, Board Sraff
Flathead County Sanitarian, 1035 1" Avenue West, Kalispell, MT 59901
Mark Brooke, Morrison-Maierle, P.Q. Box 6147, Hcicna, MT 59604