Lahontan Board Presentation.March13.2019.JT.FinalPCE Contamination in South Lake Tahoe
Lahontan Regional Water Quality Control Board, March 14, 2019
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introductions
Lukins Brothers
Water Company, Inc.
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PCE Contamination
PCE contaminant plume 400+ acres
Impaired both public and private water system wells
PCE Detection
LBWC – 3 Wells
TKWC – 2 Wells
PCE Treatment
TKWC – 1 Well
500 GPM GAC
Water production capacity reduced
3.25 MGD
11 wells impacted or at risk
12 MGD
72% of Supply
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South Tahoe PCE projects
PCE detected in TK#1. Under MCL. Remains in service.
Planning, design & engineering for GAC treatment on LB#5 (grant funding).
Monitor TKWC Well 2 for vertical contamination extent.
2015
2016
GAC at LB#5 - Implementation grant awarded (grant funding).
2017- Present
Feasibility Study – Remediation Alternatives (grant funding).
PCE detected in TK#2. Exceeds MCL. Well is shut down.
Preliminary Engineering Report completed - Treatment Alternatives, LB#2, LB#5.
GAC filtration installed on TK#2. Capacity limited.
2014
2013
PCE detected in LB#2 and LB#5. Exceeds MCL. Shut down. STPUD intertie opened.
2008
Groundwater Investigation (grant funding).
TKWC Facilities Plan developed to address PCE.
2017
2018
2016/17
Money spent to date???
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Community PCE costs
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Request for Lrwqcb
NEAR-TERM
Sentinel wells to monitor PCE movement toward water sources.
TK#1 piping modification for portable GAC connection.
TK#2 zone testing to determine extent of contamination.
Well destruction at LB#2 and LB#4 to remove possible contaminant pathways
LONG-TERM
Support for implementation funding for recommended alternative identified in Feasibility Study:
Capital Costs
O&M Costs
Questions ?
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