EXH2124033832

Model Toxics Control Act (MTCA) Cleanup Levels and Risk Calculation (CLARC II) February 1996 Introduction This document is the annual update to the MTCA Cleanup Standards. The tables have been reprinted in their entirety, and this document can be used without the aid of previous versions of these tables. The attached summary (Pages 14-17) specify the revisions, as well as compounds recently added to the list. There is a new section for "Chemicals of Note" starting on Page 2. We are also including with this issue the Natural Background Soil Metals Concentrations summary (Page 13). Reminders: • Excessively High-Risk Based Cleanup Levels The use of CLARC II data can result in the calculation of excessively large cleanup levels for approximately 100-125 contaminants. This occurs primarily in the Method C Industrial Soil Category for non-carcinogens. Percent level concentrations of contaminants such as chromium (111),1,1-dichloroethane, xylenes, etc. have been calculated. Users of CLARC II should be aware that these calculated cleanup levels may not be acceptable for a site when considering other factors, such as the potential for cross-media contamination and the need to protect natural resources (groundwater, sediments, harvestable shellfish beds) and populations that may be at a disproportionate risk. • Rounded Values The CLARC II database includes reference doses. For printing purposes, the presentation of reference doses in this report are rounded "to four decimal places". That is, if they are less than "1" they will look like ".XXXX", where "X" is a whole number. This number may be rounded…

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PSCAA Advisory Council Meeting Agenda
Add to CalendarMWednesday Mar 11, 9:00am - 11:35am
1904 3rd Avenue, Suite 105, Seattle, WA 98101
Call to order – Roll Call – Quorum Established – Land Acknowledgement We would like to acknowledge that our Agency operates in four present-day counties, which are the traditional lands of the Coast Salish people, past and present. This acknowledgement does not take the place of authentic relationships with indigenous communities in our jurisdiction and [...]