Waste MINZ 2007 Contaminated Site Case Study

Waste. MINZ 2007 Contaminated Site – Case Study Former Market Garden Land

Former horticultural land • Residential development in 1960 s • Redevelop to allow second dwelling • Historical aerial photos show buildings associated with market gardens • Initial sampling showed significant levels so further grid-based sampling

Investigation results/remediation • Concentrations above residential guidelines for As, Cu, Pb and DDT • Abandon project – responsibility to advise? • Leave on site with exposure barrier • Excavate and dispose to landfill • Surrounding properties?

Building consent • T&T to provide a PS 4 (producer statement construction review) confirming that the recommendations in their Contamination Report have been satisfied • PS 4 for observation of all earthworks and excavations to ensure conditions encountered consistent with findings

Land use consent • Undertake remediation works according to the Assessment of Environmental Effects Report and Contamination Site Remediation Action Plan prepared by T&T • Following completion of excavation works undertake a validation exercise to confirm remediation works and identify residual contamination. Provide SVR

Land use consent • All earthworks under the supervision of registered engineer experienced in geotechnical engineering. Final geotechnical certificate and as-built plans showing extent of fill along with brief geotechnical report highlighting any particular stability or foundation requirements

ARC consent? • Queried proximity of groundwater and probability of contamination • Approved as permitted activity in accordance with RAP and provide SVR