fcfizj West Lake Update August 4,2015 Limited Brush Clearing Soon in Operable Unit 1, Areas 1 and 2 EPA Region 7 has directed the Potentially Respon- sible Parties to perform additional site work to supple- ment radiologically impacted material (RIM) volume calculations to assist in the evaluation of potential remedies. This additional work will take place in Areas 1 and 2 of Operable Unit 1 of the West Lake Landfill. The additional work directed by EPA will require the limited clearing of brush from some areas of the land- fill for drilling access. The clearing of vegetation will follow the previously approved process used for fence construction and Gamma Cone Penetration Testing work conducted in 2013. Prior to any clearing activities in an area containing RIM, the area will be scanned for gamma radiation. If the scan indicates a radiation level above background, the crew will be directed to avoid ground disturbance in that area. Latest EPA Study Confirms Accuracy of NATTS VOC Air Data In February 2015, EPA released an off-site air data summary report, which outlined the results of air moni- toring efforts for volatile organic compounds (VOCs) at five off-site locations surrounding the West Lake Landfill. The data in this report demonstrated that the levels of VOCs in the air surrounding the landfill are similar to levels in other parts of the city. EPA has now released a new report for the National Air Toxics Trends Sites (NATTS), including the one in St. Louis. The St. Louis NATTS site is located on Blair Street in downtown, and has continuously recorded air quality data since 2005. The 2013 VOC temporal study is one of a number of performance tests that EPA con- ducts to verify the accuracy of the NATTS air monitoring stations. NATTS data are also periodically reported to Congress. The reports are available online: www2.epa. gov/sites/production/files/2014-08/documents/082114- urban-air-toxics-report-congress.pdf With the accuracy of the St. Louis NATTS data con- firmed by the VOC temporal study, EPA has even more confidence in the previous air quality reports. While those reports had undergone their own quality control and quality assurance processes, the 2013 VOC temporal study provides additional assurance as to the results of those reports. With this additional assurance regarding the urban St. Louis air quality data, EPA reiterates that the data col- lected from the five-off site locations near the Bridgeton landfill in 2014 and early 2015 are generally consistent with the data collected from the NATTS site on Blair Street. While the consistency of the NATTS data and the off- site monitoring data demonstrate that urban air quality throughout St. Louis metropolitan area is similar in com- position, EPA recognizes that many people living near the Bridgeton landfill experience odor issues that have quality of life impacts. The State of Missouri, through the MDNR and the Attorney Generals office, has taken action to mitigate odors emanating from the South Quarry of the Bridge- ton Landfill, such as requiring the installation of a vinyl cover to trap gases escaping from the landfill and the construction of a leachate collection system. These ef- forts, among others, have reduced the amount and inten- sity of offensive odors escaping the Bridgeton Landfill. The 2013 VOC temporal study is available on EPA's West Lake Landfill website at: www.epa.gov/region7/ cleanup/west_lake_landfill Phase ID Field Work Complete Contractors for the Potentially Responsible Parties (PRPs), under EPA oversight, have completed the field work for the Phase ID investigation. The Phase ID in- vestigation will build on previous work conducted at the site to identify the extent of RIM in the southwestern and western portions of Operable Unit 1 (OU1) Area 1, near- est to the North Quarry, and to assist EPA in evaluating locations for a potential isolation barrier. The field work began in May and consisted of Gamma Cone Penetration Testing to screen for RIM, followed by sonic coring drill- ing to provide confirmation sampling of the screening results. The analysis of the confirmation samples takes approximately 45 days. EPA expects the final report, which will include RIM sample results, to be available in the fall. Next CAG Meeting The next Community Advisory Group meeting is scheduled for 6:30 p.m. on Monday, August 10 at the of- fices of Operating Engineers Local 513, 3449 Hollenberg Drive, Bridgeton, Mo. EPA Region 7 representatives plan to attend the meeting. Community Inquiries Ben Washburn 913-551-7364 Washburn.Ben@epa.gov Find Us On www.facebook.com/eparegion7 www.twitter.com/eparegion7 www.scribd.com/eparegion7 www.epa.gov/region7/cleanup/west_lake_landfill ------- |