2019.3.14 Lahontan Board Presentation v3South Lake Tahoe PCE Contamination
March 13-14, 2019
Lahontan Regional Water Quality Control Board| South Lake Tahoe
1
introductions
Lukins Brothers
Water Company, Inc.
2
CHALLENGE
PCE contaminant plume 400+ acres
Impaired both private and public water system wells
PCE Detection
LBWC – 3 Wells
TKWC – 2 Wells
Water production capacity reduced by 3.25 MGD
3
South Tahoe PCE projects
PCE detected in TKWC Well 1under MCL
Planning, design & engineering for GAC treatment on LBWC Well 5 (grant funding)
Monitor TKWC Well 2 for vertical contamination extent
2015
2016
GAC filtration at LBWC Well 5 implementation grant awarded (grant funding)
2017-Present
Feasibility Study to identify recommended alternatives (grant funding)
PCE detected in TKWC Well 2 over MCL, well shut-down
Preliminary Eng Report completed for treatment alternatives on LBWC Well 2&5
GAC filtration installed on TKWC Well 2, capacity limited
2014
2013
PCE detected in LBWC Well 2&5 over MCL, wells shut-down, STPUD intertie opened
2008
Groundwater Investigation (grant funding)
TKWC Facilities Plan developed to address PCE
2017
2018
2016-2017
Money spent to date???
4
South Tahoe PCE costs
5
Request for Lrwqcb
NEAR-TERM
Sentinel wells to monitor PCE movement toward water sources
TKWC Well 1 piping modification to be able to hook up to portable GAC
Zone testing for TKWC Well 2 to determine extent of contamination
Well destruction for LBWC Well 2 and LBWC Well 4 to remove possible contaminant pathways
LONG-TERM
Support for implementation funding for recommended alternative identified in Feasibility Study
6
Question and answers
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