Some additional occurrence issues were also summarized at the end of the meeting. On the first day, short presentations were given by Marc Edwards of Virginia Tech and Dennis Clifford of the University of Houston on arsenic treatment technologies, such as conventional treatment, softening, membranes, ion exchange, and activated alumina. The performance and advantages and disadvantages of each treatment were discussed. Tom Sorg of EPA discussed their ongoing work on evaluating full-scale arsenic removal. Many new and emerging technologies were discussed, but there was general agreement that these new technologies need more research prior to being mandated in a drinking water regulation.
Ion exchange generates a brine solution with high levels of arsenic and salt.
The compliance decision tree was discussed on the second day. This discussion focused on getting input on the many issues that will ultimately impact the number of systems that will install a particular treatment to comply with the new arsenic regulation. EPA and Congress will be briefed on the report on March 22. This report will likely get some media coverage, so be prepared for some arsenic questions from your local media. This report will have a major impact on where the proposed arsenic regulation will end up.