A NEW round of excavations and laboratory testing at the old Tanapag cemetery have yielded polychlorinated biphenyl levels below the standard cleanup level of 1 part per million.
The U.S. Army Corps of Engineers and its contractor Environmental Chemical Corp. conducted excavations at the site on Saturday morning.
The laboratory test results came out yesterday afternoon.
Frank Ono, on-island representative of the Army Corps, said the on-island test results ranged from 0.1 ppm to 0.295 ppm of PCB.
“All the results were below 1 ppm. We took six samples from the site,” Ono told Variety.
The excavated soil was transported to the PCB treatment site, where it would be stockpiled and treated using the indirect thermal desorption.
Ono said the U.S. Environmental Protection Agency will also conduct additional sampling at the old cemetery area to verify the results of the tests conducted by ECC and Army Corps.
EPA requires PCB contamination cleanup levels of below 1 ppm.
In the earlier characterization of the same site, the PCB levels detected ranged from 1 ppm to a little less than 2 ppm.
Ono said the excavation dates at the area near the main Tanapag road, near the PCB treatment site, were not known.
The characterization of the second area yielded up to 5 ppm of PCB, according to the Army Corps.
While the Army Corps and ECC treat the remaining stockpiled PCB-laced soil, they continue to find and excavate new contaminated areas.
They were also able to ship out of Saipan 60 bags of PCB filter cake and 10 bags of liner waste which will be transported to Nevada—not Utah as earlier reported.
There had been over 20,000 tons of PCB-contaminated soil stockpiled at the treatment area. About 12,500 tons had already been treated.
PCBs are suspected cancer-causing chemicals.
