Quarry gets clamp down under review of consent conditions
An Auckland Regional Council review of a Winstone Aggregates Ltd consent to take groundwater from the Three Kings Quarry
has resulted in tougher restrictions on dewatering at the quarry.
The review was ordered by the ARC, after inaccurate information on the effects of dewatering was provided in the
original consent application in 1997.
The review decision, made by three independent commissioners, stated that Winstone could continue dewatering the Mt Eden
Rd quarry, in order to extract scoria, but only if stricter controls and monitoring were implemented.
The commissioners based their decision on rigorous scientific analysis of potential environmental impacts from
groundwater removal.
Winstone will now be required to monitor ground settlement levels from dewatering every three months, as opposed to
every six months under the original consent. The designated monitoring area is also substantially larger than it was
previously.
The dewatering is to cease once ground settlement limits, which are four times more stringent than in the original
consent, have been reached.
A bond of $5m, which would be used to mitigate any unforeseen environmental impacts that may occur, is also required.
ARC water resource scientist Alastair Smaill said studies of the quarry site showed that environmental impacts from
taking additional groundwater would be negligible if dewatering restrictions were imposed.
“In making this decision community interests were paramount,” Mr Smaill said. “As a result the commissioners have
imposed strict conditions on the quarry in order to protect the community from potential risks of dewatering.”
The commissioners assigned to the review were two expert engineers, Dr Laurie Wesley and Graham Wheeler, and long-time
commissioner Ken Graham. Appeals relating to the decision must be lodged with the Environment Court within 15 working
days of the decision.