Additional samples taken March 16 showed that the water at the four beaches was clean, said Grace O. Garces, Guam Environmental Protection Agency spokeswoman. Daily monitoring of Tumon's waters will continue for the next 26 days, Garces said. Garces said that, based on historical trends, Tumon Bay is rarely listed on the environmental agency's beach advisory list, when compared to other beaches. Officials have said there is a direct correlation between the bay's pollution and a recent breakdown of the sewage system in Tumon. Guam Waterworks Authority crews discovered overflowing sewage from the Fujita Pump Station and from manholes around Tumon on March 3.
Tourists are far more enthusiastic about swimming in the bay than Guam residents.
The Guam Environmental Protection Agency publishes reports on Guam's beaches, including three-year trend charts. Samples are taken to a Tiyan lab, where part of the sample is diluted with sterilized water. A fluorescent agent is added to the indicator organism to allow staff to count the glowing bacteria after they incubate and multiply for 24 hours. The more bacteria cells counted, the higher the presence of bacteria from wastewater contamination. An advisory is issued if the week's sampling results show bacterial concentrations are above the accepted Guam Water Quality Standard for recreational beaches.