NC0026051_Sludge final updates_20080206

FEB - 6 2008
January 31, 2008
Re: Final Update on Triangle Wastewater Treatment Plant Sludge Storage
Dear Mr. Wiggins:
cc:
JRP/js
Richard Simms - Project Manager
Glen Vance - United Water ORC
120 E. Parrish Street. Law Bldg., 1st Floor, Durham, N.C. 27701 [phone] Fax [phone]
Equal Employment/Affirmative Action Employer
Mr. Mack Wiggins
Raleigh Regional Office
NCDENR-Division of Water Quality
1617 Mail Sendee Center
Raleigh, NC 27699
COUNTY OF DURHAM
ENGINEERING DEPARTMENT
Sincerely,
/ Joseph Pearce, P.E.
Utility Division Manager
If you need any additional information or have any questions, please feel free to contact
me.
As a final update on sludge storage at the Triangle Wastewater Treatment Plant, Bio-
Nomics removed 1704 dry tons of sludge from Triangle Wastewater Treatment Plant
lagoon. Dredging and dewatering ended this week. The dewatered residuals were
transported to Earthtech for stabilization and disposal. This process has occurred without
any known incidents or complaints. A new pennanent aerated and mixed sludge holding
tank system, centrifuge, and truck loading facility is under design by McKim and Creed.
This facility is predicted to be constructed during 2010. (It may be installed earlier
depending upon authorization to construct approval time). In the interim, the Triangle
Wastewater Treatment Plant will continue to store sludge in the lagoon and to have it
removed on an annual basis.
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