Postaudit Study of DBCP and EDB Contamination in the Pearl Harbor Aquifer

Protecting the Vital Groundwater Sources of Oceanic Islands

“…The decline of pollutant levels occurring in some of the wells is slow, and concentrations are expected to remain above the MCL without active treatment. Our modeling projections point to the estimation that the peak for DBCP in Mililani I should have occurred in the 2010s, while the MCL will still be exceeded in the 2040s (Figure 6); these are drastically different from the projections of Rungvetvuthivitaya et al (2007), which estimated these to occur in the years 2000 and 2010, respectively. Similar estimates for our study were obtained for TCP.…”

“…It seems a peak occurs around the year 2014, although there is uncertainty about the peak concentration and timing because of the scattered data shown in Figure 2 and the data gap from 2009 to 2012. The lack of clear peak information was also a limiting factor for the study by Rungvetvuthivitaya et al (2007).…”

“…Close to 40 years after the large‐scale contamination was discovered, the concentrations in the Mililani wells still remain above the state MCL for both DBCP and TCP. A modeling study by Rungvetvuthivitaya et al (2007) predicted a peak arrival of DBCP around the year 2000 for Mililani I, and the respective time to reach the MCL was estimated around the year 2010. Those modeling efforts have been updated in the current study using the new monitoring data shown in Figures 2 through 5.…”