The samples were collected on Oct. 11 and Oct. 16, and the analyses were conducted by Eurofins Eaton Analytical, an EPA-certified laboratory in California.
A third sample was collected on Oct. 23 which is currently out for testing.
GWA's Y-15 water well in Yigo was outfitted with an interim water treatment system on Oct. 12. Photo by Skyler Obispo
“After two more consecutive weeks of satisfactory laboratory results, GWA will confer with [the Guam Environmental Protection Agency] to lift the ‘Do Not Drink without Treatment’ advisory issued to affected GWA customers in the Yigo/Santa Rosa area,” GWA said.
Until then, the utility will continue to operate the GAC treatment system at Y-15 and until the permanent treatment system is completed.
According to Oct. 21 dieldrin sampling results from 124 GWA wells, 83 locations showed a running annual average of 0.00 to 0.10 parts per billion (ppb), while 32 locations had no traces of dieldrin. Two locations — D-17 in Mangilao and Y-15 in Yigo — tested at 0.2 to 0.5 ppb and 0.5 ppb or higher, respectively.
D-17 according to GWA has been offline since July 31 with treatment under construction.
On Oct. 10, GWA launched its point-of-use and point-of-entry treatment system programs which supplied NSF 53 or NSF 401 certified treatment systems to affected customers or provided reimbursements to customers who had purchased their own systems.
“While the interim GAC system provides strong treatment performance at the facility level, the POE program offers an additional safeguard and peace of mind for customers until GWA’s permanent GAC treatment system is fully operational,” the utility said. mbj
The Guam Registered Apprenticeship Program saw tax credit claims surge by nearly 40% in fiscal 2026, reaching $17.4 million as local businesses sought to offset operating costs and build skilled local labor.
Unofficial results for the 2026 General Election indicate Republican gubernatorial team, Vice Speaker Vicente Anthony "Tony" Ada and businessman Edward “EJ” Calvo, will head to Adelup with Alicia Limitiaco as Guam delegate to Congress, and Phillip James Tydingco to be the next Attorney General of Guam.
