Rock blasting starts in Three Kings tomorrow, a prospect filling some residents with dread.
Winstone Aggregates, the Fletcher Building subsidiary that owns Three Kings Quarry, will carry out a production explosion at 10.15am in the first of a series of attacks on a basalt rock plug at the heart of the quarry.
Alan Bigelow, who lives in the area, is concerned about effects on traffic, people walking in the Three Kings Reserve and the prospect of a long programme in the quiet residential area which he said could last up to 18 months.
"Whether traffic up Mt Eden Rd has to be stopped, what happens to people walking their dogs through the reserve - it all raises concerns about noise and if there just happens to be flying rock where a blast goes wrong and stuff flies out of the quarry floor," Mr Bigelow said.
Winstone has issued an invitation for people to watch and expects at least 50 to visit, asking for initial registrations before people arrive.
"We will be viewing the first production blast from within the confines of Three Kings Quarry," the company said.
"Therefore it would be appreciated if you could enter the site on foot at 985 Mt Eden Rd. A Winstone Aggregates employee will be stationed at the front entrance and they will direct you to an area to discuss the process ... We will then walk to a dedicated viewing area."
Winstone's environmental manager, Andrea Cave, said a pre-blast siren would warn people "to reduce the startling effect of unexpected ground vibration and air overpressure" from the blasting.
Winstone is asking visitors to stay within the viewing area, wear closed toe or sturdy shoes and dress appropriately
"After this first production blast we would welcome any feedback on sirens, signs and blasting notification process," the firm said.
Signs are up on Mt Eden Rd, in the Mt Roskill Community House, Three Kings Shopping Centre, Big King Reserve and the Three Kings/Mt Roskill Library.
Thousands of people live in the area, which is home to Three Kings School and Carlson School.
Winstone has consent to fill in the quarry on its 15.1ha site, using about three million cubic metres of material.
THREE KINGS QUARRY
* Auckland's largest scoria quarry.
* Operating for more than 80 years.
* Blasting will move hard core.
* Floor can be "evened up".
* Site will be then ready to be filled.
* Quarry is 34.5m deep.
* Equivalent to 11-storey building.