Site Description and History Previously New Zealand’s worst
contaminated site Decades of pesticide pollution by
the Fruitgrowers Chemical Company (FCC)
Site Description and History Previously New Zealand’s worst
contaminated site Decades of pesticide pollution by
the Fruitgrowers Chemical Company (FCC)
FCC opened factory in 1932, manufacture of organochloride pesticides began in 1945
During this time, houses developed to south of site and commercial properties developed to the north.
Site Description and History Previously New Zealand’s worst
contaminated site Decades of pesticide pollution by
the Fruitgrowers Chemical Company (FCC)
FCC opened factory in 1932, manufacture of organochloride pesticides began in 1945
During this time, houses developed to south of site and commercial properties developed to the north.
FCC ceased operations in 1988 and by 1996 most of the site was owned by Tasman District Council
Site Description and History Early 1990’s onwards, site subject to a number of
environmental assessments. Remediation or management required.
Site Description and History Early 1990’s onwards, site subject to a number of
environmental assessments. Remediation or management required. Major contaminants of concern:
ORGANOCHLORINE PESTICIDES
Site Description and History Early 1990’s onwards, site subject to a number of
environmental assessments. Remediation or management required. Major contaminants of concern:
ORGANOCHLORINE PESTICIDES Heavy metals
Site Description and History Early 1990’s onwards, site subject to a number of
environmental assessments. Remediation or management required. Major contaminants of concern:
ORGANOCHLORINE PESTICIDES Heavy metals Other pesticides
Site Description and History Early 1990’s onwards, site subject to a number of
environmental assessments. Remediation or management required. Major contaminants of concern:
ORGANOCHLORINE PESTICIDES Heavy metals Other pesticides Herbicides
Site Remediation October 2004-
early 2008 9 sections
site and foreshore
3D “jigsaw” of excavation 65,000m3
200+ individual cells
On-site Soil Treatment Pre-treatment soil
drying Mechano-Chemical
Dehalogenation (MCD) Base metal reagent →
Chlorine ‘stripping’ Vibratory ball-mill 15mins at 70-100oC
Soil Acceptance Criteria (SAC)
Difficulties in Remediation Large scale Uneven contaminant spread Discoveries of buried chemicals Inexperience, untried
technologies Greater risk No policies/ regulations
Unknown effects to groundwater Residential area at risk to
exposure
Impacts of Treatment Poor management and control of
process Secondary contamination of copper,
mercury Improper disposal of cleaning reagents
and by-products Pollution of water courses
Excessive soil drying Organochlorine converted to harmful
dioxins Released to air due to inadequate
emission filtration
Alternative Solution (1) Containment of contaminated
ground Clay capping and subterranean bund
wall Advantages
Cheaper than soil treatment Often safer as contaminants not
disturbed → no risk of release Disadvantages
Prevents any further use of site → open space, commercial or residential
Groundwater flow and tidal movement interactions causing contamination of the foreshore and marine areas
Alternative Solution (2) Off-site soil treatment Advantages
No need to install own treatment plant → cheaper
Any mistakes in processing impact on the facility not the land targeted for improvement
Disadvantages Residential area at greater risk of
exposure due to excessive disturbance
Continual “trucking” of large quantities of material causes residential/traffic disturbance