WHAT happens to the human waste that Saipan’s 70,000 residents discharge daily?
And what about the wastewater that the community produces every day?
After the treatment process, part of it goes to the ocean through a pipeline called the outfall, according to the Commonwealth Utilities Corp.
However, the solid powder residue from the treated wastewater, which is called “sludge,” stays on island.
This sludge is now a big problem for CUC which has not found a place for its disposal.
“That’s the biggest issue right now in the commonwealth. What can we do with the powder. We would like to legally give it to farmers so that they can use it for fertilizers,” CUC spokeswoman Pamela Mathis said.
This may be good news to farmers who spend a significant amount of money on fertilizers for their crops.
But there’s still a catch. Under the current regulations of the Division of Environmental Quality, the sludge cannot be distributed as fertilizers or compost to farmers.
The only way to do this is to amend DEQ’s regulations. Until that happens, the sludge will continue to accumulate at CUC’s treatment plants.
The treatment
There are currently two treatment plants on Saipan—in Agingan Point and in Kagman.
Each uses aerosion or biochemical treatment to kill the bacteria.
Mathis said this is a more modern type of wastewater treatment, even better than Guam’s primary method which uses water-filter and rocks to clean the wastewater.
“On Saipan, the treatment for wastewater method is called ‘secondary.’ Although it’s called secondary, it doesn’t mean that it’s less than first. ‘Primary’ is the older treatment which is used on Guam and other parts of the U.S.,” she said.
The first step in the secondary method is blowing air into the wastewater treatment system so that it moves around and interact with the bacteria that will eventually clean it.
The good bacteria “eats” the bad bacteria.
After the aerosion process, the waste will settle on the bottom of the big wastewater basin. Then it will go into a pipeline which is sometimes referred as the “outfall,” Mathis said.
“The outfall sometimes can go into the ground and then it will be treated through the rocks. But here on Saipan, our outfall goes to the ocean through the pipeline,” she said.
“There’s another step on the treatment which is step 4. That’s when the air of that water hits the ocean water and then the salt and the ocean water also kill the leftover bad bacteria. Salt is very good for killing whatever is left over and then the solid that settles,” she added.
The water surrounding the pipeline is constantly monitored and checked by authorities.
“We do tests in the ocean at that pipeline so if it’s 100-ft. out into the ocean then we would have divers going down to get samples of the water back which will be tested to see how the treatment level is at the pipe,” Mathis said.
“Then we will build a circular radius to see how the ocean is affected by the outfall. That is part of the program,” she added.
The Kagman and Agingan treatment plants may be upgraded this year.
The Agingan Point wastewater project would cost $5.6 million. The job entails replacing the existing intertidal outfall serving villages near the area such as San Antonio, Koblerville among others.
A 1,100-ft. long, 24-inch outer diameter high density polyethelene pipeline will be constructed to discharge secondary treated wastewater at about 100-ft. depth in the ocean.
The Kagman wastewater plant and collection system would use a new method called the wetland, which needs at least $8 million to be constructed.
Both treatment plants have secured permits from the Environmental Protection Agency and are inspected two times a year.
