EXH0036017499

Subject: RE: Acceptable Fill Criteria Language for Draft 401 Certification DELIBERATIVE DOCUMENT CURRENTLY EXEMPT FROM PUBLIC DISCLOSURE If we are not going to restrict fill material to naturally occurringuncontaminated soils, I recommend you use the following language to address potential impacts on plants and animals. The intentof this language is to ensure the fill material used would be "clean enough" that itwould not be expected to cause adverse impacts on plants and animals that come in contact with it. Note that this does not address potentialhuman health exposure pathways or protectionof aquatic organisms,which will need to be addressed with other language. There are several elements to this recommendation: First, is the listof chemicals Of concern. I am recommending we use the list in Table 749-3. While lengthy,this listrepresentsthe morecommonlyoccurringcontaminantsthat haveinformationon potential terrestrial ecological impacts. Only those suspected of being present at the site would have to be tested beyond those you are already specifyingthey test for. Second, I am recommending we requirethe fill material to meet the most stringent value in Table 749-3 unless bioassay testing is conductedthat demonstrates the fill is not toxic to plants and animals. The table 749-3 values are considered screening values for ecologicallysensitive sites. Third, as a further safeguard, I am recommendingthat the uppermost 6 feet of fill placed be required to be clean natural soil. This is the zone where most soil biologicalactivityoccurs and will providea buffer zone that prevents most plant and animal contactwith any deeper contaminated fill material. It should also minimize…

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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 [...]