14,500 tons of sludge cleaned from former paper mill

The Harbor Paper mill aeration basin is once again empty at a lower-than-expected cost thanks to efforts by PUD crews, its administrator says.

On Dec. 30, after years of holding the water and sediment that remained from the treatment of wastewater, the 4.5 acre basin was empty for the first time since the completion of its construction in the summer of 1977.

“It’s a significant moment in the Grays Harbor PUD’s efforts to remove and demolish the Harbor Paper wastewater treatment facility,” PUD General Manger Dave Ward said. “From the beginning of this project, our goal has been to find ways to complete the work with the smallest possible impact to our customers. The work in the aeration basin is one of the best examples of innovative thinking and cost saving solutions that we have.”

After examining multiple options for the loading and transport of the sludge, the PUD chose the method with the lowest cost — renting trucks, trailers and a loader and hiring drivers and a loader operator to transport the material to the Cowlitz landfill, the closest landfill licensed to receive it.

When the last dump truck rolled out of the basin carrying the final load of “sludge” to the landfill, the PUD trucks had made a total of 525 trips to Cowlitz County over a three-month period, shipping some 14,500 tons of sludge with an average of more than 27 tons per trip. The final cost of sludge disposal totaled $490,000.

“Had the PUD used a private contractor, the cost for hauling and dumping the sludge would have been between $720,000- $900,000,” Ward said. “Thanks to our dedicated staff, the PUD arrived at a solution that responsibly disposed of thousands of tons of industrial waste and did so at a significant savings to the PUD and its customers.”

While it’s a significant accomplishment, there remains much work to be done. Under its agreement with Rayonier Properties LLC, the PUD must to clean and remove the facility’s water treatment system and remove solid byproducts including the basin sludge and piles of bark/rock mixture, sand ash and boiler grate material.

As of Dec. 16, nearly 11,000 tons of boiler grate ash had been removed with more than 19,000 tons remaining, as well as some 3,206 tons of sand ash with more than 28,000 tons remaining. The PUD has begun work to haul away primary solids from the wastewater treatment site, and concrete rubble and bark/rock removal has not yet begun. The PUD is aiming to complete cleanup sometime this spring.