SUNCOR. Four Seasons Cleaners. B s Cleaners

Transcription

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2 SUNCOR Four Seasons Cleaners B s Cleaners

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4 Former Gas Station

5 GW-8 < GW-9 < GW Flow GW-4 GW Benzene mg/l PCE mg/l GW GW

6 Former Gas Station Four Seasons Dry Cleaner

7 Has been a dry cleaner since the mid-1960 s In response to GW sampling data, was inspected on December 14, 2012 Started with four transfer machines, eventually converting to dry-to-dry machines Unlined concrete holding tanks in basement for cooling water and for separator water Perc stains from the transfer machines on basement wall, used as late as 2002.

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12 Operation suggests a release occurred, since concrete does not act as a barrier to PCE movement Cited for failure to minimize the possibility of an unplanned release (261.5(b)(5)) Compliance Order on Consent being drafted Months can elapse between a decision being made and signing the order Situation demands immediate response

13 The Finger Pointing Begins Former Gas Station Four Seasons Dry Cleaner

14 GW-8 < GW-9 < GW Flow GW-4 GW Benzene mg/l PCE mg/l GW GW

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16 The Finger Pointing Continues Former Gas Station Former Dry Cleaner 1950 s to mid 1960 s Four Seasons Dry Cleaner

17 The Finger Pointing Continues Coin-Op Laundry Former Gas Station Former Dry Cleaner Four Seasons Dry Cleaner

18 GW Sampling data suggests high potential for vapor intrusion Four Seasons has limited resources and questions whether they are the sole source Do not want to delay indoor air testing CDPHE requests EPA Emergency Response to conduct indoor air testing. EPA agrees. Planning commences immediately to conduct air sampling

19 City and County of Denver Environmental Health Department notified of our findings U.S. EPA notified, requesting their assistance City and County of Denver District 8 Councilman notified Events rapidly unfolding in late December Decision made to begin public notification immediately after the holidays Planning meetings to sequence events

20 First Round of Indoor Air Sampling GW Flow Four Seasons Dry Cleaner

21 Letter / fact sheet prepared All sampling equipment secured Letters mailed to property owners Telephoned property owners / residents CDPHE and EPA visit target properties to speak to homeowners, pass out fact sheets and collect samples if access granted Repeat last two steps when residents not home All samples collected over 3 days time

22 First Round of Indoor Air Sampling No Sample / 580 Non Detect No Sample No Sample 5 / Four Seasons Dry Cleaner 520 / 530 EPA PCE Action Level 41 ug/m3 CDPHE PCE Action Level 4.1 ug/m3

23 First Round of Mitigation System Installation No Sample MITIGATION MITIGATION Non Detect No Sample MITIGATION 6.8 No Sample MITIGATION MITIGATION Four Seasons Dry Cleaner MITIGATION EPA PCE Action Level 41 ug/m3 CDPHE PCE Action Level 4.1 ug/m3

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25 On December 15, 2011 Department revises its indoor air screening concentrations Residential Action Level Pre 12/15/11: 31.0 ug/m3 (R=10-4) Post 12/15/11: 4.1 ug/m3 (R=10-5) On February 10, 2012 EPA s IRIS publishes its new PCE toxicological review Post 02/10/12: 41.7 ug/m3 (HQ=1)

26 35 / / / / 36 Non Detect GW Flow New CDPHE PCE Action Level 41.7 ug/m3 Four Seasons Dry Cleaner Second Round of Indoor Air Sampling

27 MITIGATION MITIGATION 1.7 / / 36 Non Detect New CDPHE PCE Action Level 41.7 ug/m3 Four Seasons Dry Cleaner Second Round of Mitigation System Installation

28 GW Flow Four Seasons Dry Cleaner Future Round of Indoor Air Sampling

29 Complete iterative indoor air sampling / mitigation system installation process Begin investigation of nature and extent of releases of PCE to soil and groundwater at Four Seasons Dry Cleaners and Former Gas Station Negotiate Compliance Order on Consent with Parties with demonstrated releases Notify other potentially responsible parties and request/order investigation of PCE releases

30 David Walker Solid and Hazardous Waste Program Hazardous Materials and Waste Mgmt. Division Colorado Dept. of Public Health and Env Cherry Creek Drive South Denver, CO