EXH0025017310

1. Draft Fill Criteria requirements for the 401 Water Quality Certification for the SeaTac Third Runway Embankment project. Oean FillCriteria for 401 C..e... 2. Spreadsheet derivingthe surface water ciJalitycriteria needed for the three-phase model calculations for soilcleanup levels for the protectionof surface water. seate_xls 3. Spreadsheet deriving the ground water cleanup levels, the three-phase model calculationsfor soil cleanup levelsfor the protection of groundwater, and the three-phase model calculations for soil cleanup levels for the protection of surface water. Three-Phase Hodel.xL_ 4. A summarytable showing the various soil cleanup levels, natural background concentrations, and PQLs. Hazardous Subs_nces.doc The fill criteriarequirements have been developed usir,g the Amendod MTCA. I have included relevant sectionsof the regulation into the developmentof the fill criteria. Specifically, I have Jeveloped fill criteriabased on the Method A Soil Cleanup Levels (Table 740-1); derived soil cleanul:: levels using the three-phase model in WAC 173-340-747 first for the protectionof ground water and second for the protectionof surface water; reviewed soil concentrations presented in Table 749-2 ! AR 017310 u,,,I._:,_11 _._.'.,: (ecological standards), reviewed natural backgroundsoil metals concentrations:and reviewed PQL values for the metals under consideration.The listing of metals being proposed for the fill criteria is based on 40 CFR Part 122 Appendix D Table III (Other Toxics Pollutants). These are required monitoring parameters for the NPDES program. The bases for the fill criteriaare: 1. Use Method A (Table 740-1 ) values if available. 2. If not, use the lowervalue of Method B, protection of either ground water or surface water.…

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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 [...]