Manly Lagoon Dredging Project - Manly Council - NSW Government

Manly Lagoon Dredging Project – Review of Environmental FactorsPrepared for Manly and Warringah CouncilsKey:Proposed Dredging AreasFigure 5.1: Acid Sulfate Soils Risk Map for Proposed Works Site (After: Natural Resource Atlas, 2009)The sediment sampling undertaken by PBP in 2001 indicated the following results withregards to the proposed dredging areas within the Lagoon (PBP, 2002):Sediment found at the downstream end of Burnt Bridge Creek (near the confluencewith the Lagoon) poses a low acid sulfate soil risk;Sediment found in the upper portion of dredging works within the Lagoon poses a lowto very high acid sulfate soil risk; andSediment found at the lower portion of dredging works within the Lagoon poses a lowto very high acid sulfate soil risk.The proposed dredging works will be undertaken in an area identified as Class 1 AcidSulfate Soils according to Manly and Warringah’s Acid Sulfate Soil Maps contained inCouncil’s respective LEP’s (1988 and 2000, respectively). The relevant provisions of theLEPs apply to any works to be undertaken in Class 1 areas.Contaminated LandsA search of the DECCW Contaminated Land Record on 15 July 2009 for the Manly andWarringah LGAs identified four contaminated land sites; two within Manly LGA and twowithin Warringah LGA. The only Environment Protection Authority (EPA) declared2 July 2010 Cardno (NSW/ACT) Pty Ltd 44H:\Doc\2010\Reports.2010\Rep2580v4.doc