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How it Works

Lime Stabilization
Sludge (biosolids) designated for beneficial reuse passes from the centrifuges to the lime loading facility, where pebble lime is added to raise the product's pH and destroy remaining pathogens (disease-causing organisms).  The limed sludge is then loaded into trucks for transport to landfills or to land application projects.

ALCOSOIL is processed wastewater sludge, commonly called biosoilds, and is used beneficially to reclaim damaged land and as a fertilizer for feed crops.  Resembling crumbly wet dirt, ALCOSOIL is simlar to soil humus in its formation and composition.  In addition to naturally occuring minerals and elements, the process by-product is rich in organic matter and is limed stabilized to reduce pathogens.   ALCOSAN produces approximately 60 dry tons of ALCOSOIL per day which represents 68% of the plant's total sludge disposal.

ALCOSAN's in-house laboratory performs tests daily to confirm the quality of effluent being discharged to the river, to monitor the effectiveness of the plant's industrial pretreatment program and to ensure the quality of ALCOSAN's reusable biosolid product (ALCOSOIL).


Regional Conveyance
Regional Conveyance crews perform daily inspections and maintenance of the 90-mile interceptor system and related structures, including five pumping stations on the Allegheny and Ohio rivers.  Structures not readily accessible by land are maintained by ALCOSAN's boat crew.


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Sewer Overflow Advisory key: Wet Weather overflows have ceased. Rivers, streams and creeks may still be impaired. For more information:

Customer Care at ALCOSAN, we believe it's our duty and privilege to protect, recover and reuse our most valuable resources for the benefit of our customers.

Consent Decree: To comply with provisions set forth in the Clean Water Act, ALCOSAN must meet a series of requirements for planning, design and construction, operation and permitting. For more information

Watershed Education: Leave small leftovers of paint and solvents to dry rather than pouring them down the drain. Learn more

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3300 Preble Avenue
Pittsburgh, PA 15233
(412) 766-4810