Town of Millbury WasteWater Treatment Plant

PLANT DATA

Startup: 1970 , Design Flow: 1.2 MGD ( Peak 2.5 MGD)

Present Flow: 1.0 MGD, serving 6368 residents

Type of Plant: Grade 4 Secondary Plant with Trickling Filters and Anaerobic Digesters Also serves Town of Sutton ( 8% of Plant flow )

Collection System: 42 Miles of Sewer lines, 8 Pumping Stations ( 7 Ejector, 1 Pump )

Discharges to Blackstone River

Total population : 12,247 ( 52% Serviced )

Upgraded in 1978, added garage and laboratory

NPDES PERMIT LIMITS:

• BOD - 30 mg/l avg monthly (50 mg/l max ) , 85% Removal
• TSS - 30 mg/l avg monthly ( 50 mg/l max ) , 85% Removal
• Chlorine - .50 Max ( Seasonal )
• Fecal Coliform - 200 per 100 ml Monthly ( 400 Max )
• pH - 6.5 - 8.0

FACILITY STAFF

Total of 5 Full Time Employees; Plant Superintendent (Grade 6 ), 3 Plant Operators (1-Grade 6, 1-Grade 5, 1-Grade 4 ) and 1 Clerk

Hours of operation: Monday - Friday 7:00 am - 3:30 pm (Limited weekend hours)

AWARDS

• 1988 DEQE & MWPCA - Operations and Maintenance Excellence Award
• 1989 US EPA - National Second Place Award for outstanding Wastewater Treatment Facility Operations and Maintenance
• 1989 NEWPCA - Operations Award - for Excellence in Plant Operations
• 1989 EPA Region 1 - The Operations and Maintenance Excellence Award

Foreground-Digester Background-Trickling Filters

Sludge Drying Beds

Facility Diagram

TREATMENT UNITS

Comminutor (1), Mechanical Bar Rack (Backup) (1), 12" Parshall Flume (1), Dorr-Oliver Grit Chamber (1), 50' Dorr-Oliver Clarifiers (2), 85' Trickling Filters (2) , 60' Final Clarifier (1), Dual Chlorine Contact Chamber (1) , 45' Pacific Flush Anaerobic Digesters ( 380,000 Gallon Capacity Each ) (2) , Sand Drying Beds (12), Carter Sludge Pumps (2) Wallace & Tiernan Chlorinators (Vacuum Type) (2) , One Ton Chlorine Cylinders (2), Propane Standby Motor (Runs 1 Standby Pump) (1)

SLUDGE TREATMENT / DISPOSAL

Primary Sludge is pumped from 2 primary clarifiers to the heated digester, where a mesophilic bacteria range is maintained (usually 90 - 95 degrees Fahrenheit). After digestion, the sludge is transferred to the unheated digester for settling. After settling, the sludge is pumped to the sand drying beds where it is dried, HAND SHOVELED, and hauled to the Wheelabrator Trash Incinerator. The sludge from the secondary clarifier is returned to the primary side of the plant to be treated. In 1996, 80 tons of sludge were hauled and disposed.

FACILITY UPGRADES

The plant was built in 1969-1970, with 75 % Federal Funds, 15 % State Funds,10 % Municipal Funds. In 1978-1979 , a garage with expanded laboratory and storage was built with 100% Federal funds. At present, a facilities plan is being developed to expand the plant to a 2.7 MGD facility with increased BOD / TSS removals , ammonia and phosphorus removals and dechlorination Earth Tech was selected for the facilities plan.

COMPUTER UTILIZATION

OPS Pac and Sidearm Maintenance Programs are used for data collection, reports and tracking unit maintenance and repair.

Chief Operator : J. Bradford Lange

Address: Providence Road, Millbury, Ma. 01527

Telephone:

• (508) 865-3780 Plant
• 508) 865-9143 Office
• (508) 865-0853 - Fax

Plant E-Mail : RSComm@worldnet.att.net ( (Rich Hamilton , Operator)