NYSDEC-APPROVED remedial action work plan

** During review of community air monitoring data for the geotechnical investigation work completed between December 4 and 19, 2021, Langan identified a discrepancy between the raw air monitoring data and the 15-minute time-weighted average calculated data presented in select daily summary reports. Corrected data indicate only minor concentration differences in VOC and mercury vapor data when compared to data presented in the original daily summary reports. Most importantly, no exceedances of CAMP threshold levels were identified for VOCs or mercury during the performance of the geotechnical investigation work.

The discrepancy was a result of a manual processing cut-and-paste error by the company providing CAMP equipment, telemetry and data processing for the recent geotechnical study.  This error resulted in duplicate datasets being used to calculate the 15-minute time weighted averages that were presented in the daily summary reports. The data summary sheets prior to December 4, 2021 and on December 19, 2021 were not affected. 

It should be noted that this was a post-monitoring processing matter that did not impact the accuracy of the real-time monitoring data that was observed by Langan field personnel during the geotechnical investigation work.  

* * During review of community air monitoring data for the geotechnical investigation work completed between December 4 and 19, 2021, Langan identified a discrepancy between the raw air monitoring data and the 15-minute time-weighted average calculated data presented in select daily summary reports. Corrected data indicate only minor concentration differences in VOC and mercury vapor data when compared to data presented in the original daily summary reports. Most importantly, no exceedances of CAMP threshold levels were identified for VOCs or mercury during the performance of the geotechnical investigation work.

The discrepancy was a result of a manual processing cut-and-paste error by the company providing CAMP equipment, telemetry and data processing for the recent geotechnical study.  This error resulted in duplicate datasets being used to calculate the 15-minute time weighted averages that were presented in the daily summary reports. The data summary sheets prior to December 4, 2021 and on December 19, 2021 were not affected. 

It should be noted that this was a post-monitoring processing matter that did not impact the accuracy of the real-time monitoring data that was observed by Langan field personnel during the geotechnical investigation work.