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Stormwater management in Canada improved with new Phoslock technology

BRAMPTON, ONTARIO, Nov. 12, 2012 -- For over a decade, the effectiveness of a niche/proprietary water quality treatment product called Phoslock® at precipitating and entrapping phosphorus has been proven on the world stage and through many research and field studies for drinking water reservoirs and freshwater lakes. Since 2008, pilot-scaled projects have been completed in Ontario (and evaluated by an independent agency) to demonstrate the effectiveness of Phoslock® to resolve excessive phosphorus issues and Blue-Green algae problems for stormwater management ponds, reservoirs, lakes and agricultural drain systems. The application protocols were approved by the Federal Government and Province of Ontario. Last week, and after harvesting excessive vegetation from a large stormwater management facility, the first major application of Phoslock® was completed for a Canadian municipality. From a maintenance perspective, the use of Phoslock® for the Loafer's Lake facility (within the City of Brampton) was determined to be more cost-effective than other available water treatment technologies or a sediment removal approach.

Phoslock® is manufactured by combining lanthanum with bentonite. The lanthanum forms a permanent electrostatic bond with the bentonite and does not leach from the bentonite. The resulting product binds strongly with phosphate forming a particulate material which will sink to a lake, pond or watercourse bed.  It is insensitive to the range of redox, temperature and pH conditions naturally found in lakes and therefore provides for a permanent removal of phosphate. Once on the bed, unsatisfied lanthanum bonds continue to bind phosphate, either released from the sediment below or from the water column above.

Applications of Phoslock® to lakes and reservoirs have been shown to reduce concentrations of phosphate in the water column to very low levels, concentrations low enough to substantially limit Blue Green algal growth. The product is most effective if applied in the late fall, ensuring that in-lake or reservoir phosphate concentrations from the next growing season are sufficiently low to limit Blue Green algal growth. Phoslock® is not a herbicide. The key mode of operation of Phoslock® is to rapidly remove almost all phosphate from the water column and through this reduction, influence the primary producers (algae) by limiting their growth.  In any lake or reservoir where there are external sources of phosphorus (e.g. from a river system or where sediment re-suspension occurs), phosphorus will be measurable in the water column. However, phosphate will continue to be bound up by the Phoslock®, as long as unsaturated lanthanum remains. Finally, so long as significant external nutrient sources to a water body continue, the period of time over which Phoslock® is effective will be reduced. Applications may then be needed for other years.

GREENLAND® is a Canadian-based engineering and technology enterprise that works in the environmental, water resources and land development engineering sectors and specifically projects with an integrated watershed management and infrastructure planning/design; information technology development; and, public‐private partnership focus.

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