Waihi's historic pumphouse slowly slides to safety

Mining company manager Adriaan van Kersen (front) and mayor John Tregidga at the site of the operation. Picture / Alan Gibson

Seven metres down, more than 293 to go.

The historic Waihi mine pumphouse has begun its slow, methodical journey to a new site 301m from where it has stood for 102 years.

Centimetre by centimetre, the 21-metre-high, 1840-tonne pumphouse is being pushed to its new home using a system of jacks, beams and slippery Teflon sheets.

The move began on Monday morning and by yesterday afternoon the pumphouse, built by Cornish miners to remove water from the Martha Mine, had been gently slid 7.2m.

Each day for the next four to six weeks, engineers hope to push it from the original site, which is unstable and threatens its survival, to a plot 26m to the south and 270m to the west where the ground is firm.

The $4 million preservation effort is being undertaken by Newmont Waihi Gold as part of the terms of its resource consent for operating the mine.

Since the 1960s, the pumphouse has had a 30cm, 1.5-degree tilt after a mineshaft collapsed and the earth beneath it subsided.

The first stage of the move is getting it upright.

"Once we're on flat ground, life should become easier," Newmont general manager Adriaan van Kersen said yesterday.

Mr van Kersen and Hauraki Mayor John Tregidga took the Herald to the site, which has been closed to the public since the 1980s, to view progress.

The huge shell of the pumphouse dwarfed the crew of 10 engineers watching every step of the highly controlled move, but the structure made surprisingly little sound as it slid a few centimetres at a time on the oiled Teflon sheets placed on concrete beams inserted underneath its hulk.

Ten jacks, each capable of carrying 250,000kg, propped the leaning northern face of the building, while steel beams reinforced it internally.

Mr van Kersen said the possibility of collapse was small.

As the pumphouse proceeds on its way, the 18m concrete slider beams beneath it will be moved five times to provide the track needed to take it the full distance.

The Hauraki District Council, the Historic Places Trust and a community group are also involved in the project, which aims to turn the pumphouse, unused since 1913, into a tourist attraction. A street party on September 30 will celebrate the move.