New Regulations Pave the Way for New
Wastewater Methods

Increasingly, laboratory managers who test wastewater are moving to easy, rapid methods for wastewater compliance. This is due in part to the switch from monitoring fecal coliforms to E. coli in wastewater. In 2003, the U.S. EPA specified in the Ambient Water Rule, that E. coli and enterococci are better indicators of public health than fecal coliforms. In particular, this change allows wastewater permitees to specify E. coli instead of fecal coliforms as a parameter in their National Pollution Discharge Elimination System (NPDES) permits. To date, 19 states allow wastewater permitees to specify E. coli in NPDES permits, and this list continues to grow (See map below).

In August 2005, the U.S. EPA published the proposed Wastewater Rule, which is expected to promulgate later this year. In this rule, the U.S. EPA specifies methods for the examination of E. coli and enterococci in wastewater. IDEXX’s Colilert® and Colilert®-18 reagents with Quanti-Tray® are included among the methods specified for E. coli analysis, and Enterolert® with Quanti-Tray is specified for enterococci analysis.

Quanti-Tray, when used for wastewater testing, offers significant advantages over traditional methods. A Quanti-Tray test takes less than one minute of hands-on time to run and provides quantitative E. coli results in 24 hours with Colilert, and results in as little as 18 hours with Colilert-18. Enterolert provides enterococci results in 24 hours, a full day faster than traditional membrane filtration methods.

Laboratories across the U.S. have realized the benefits of Quanti-Tray in their facilities. John Rigdon is the Operation Support Manager for United Water, the operator of the wastewater treatment plant in Cumberland, Indiana. Cumberland has been using the Quanti-Tray system for about one-and-a-half years to enumerate E. coli in their wastewater effluent.

Quanti-Tray’s easy test setup and result interpretation played an important part in the Cumberland facility’s decision to switch to Quanti-Tray. In particular, Rigdon cites, “Quanti-Tray is simple to use and reduces any chance of contamination in the laboratory. Test results are also easier to interpret than membrane filtration.”

Louise Grant is the laboratory manager at the Paris Utility District in South Paris, Maine. Her laboratory is using Colilert-18 and Quanti-Tray for both their drinking-water testing and wastewater testing. “We had been using IDEXX presence/absence tests for our drinking-water samples for many years, so using Quanti-Tray for our wastewater testing made sense,” says Grant. The South Paris utility has also switched their drinking-water samples from a presence/absence format to the quantitative Quanti-Tray. Grant explains, “We are also using Quanti-Tray for our drinking-water tests now, because a quantitative result gives our customers more information.”

For more information on how to switch your laboratory to Quanti-Tray, contact us at 1-800-321-0207.

IDEXX Launches Filta-Max xpress® for Cryptosporidium and Giardia

In May of this year, IDEXX launched the Filta-Max xpress® system, a next-generation of the Filta-Max® system that offers laboratories significant improvements in ease of use and efficiency in the capture and recovery of Cryptosporidium and Giardia. In particular, Filta-Max xpress has been specifically designed to:

• Effectively capture and recover oocysts and cysts from a wide range of turbid waters
• Dramatically simplify the processing of filters, thereby saving time and labor.

The whole process takes less than two minutes and is fully automated—just one press of a button is all that is needed to elute the filter. Filta-Max xpress is the easiest and fastest Cryptosporidium and Giardia capture and recovery system available.