Page 60 - 00 Volume 5 The Mine

further out in the lake to get at the seam as it shelved
down deeper to the north. The importing from
Australia of a powerful dredge was undertaken and it
was used to chew up the lake bottom and pump the
slurry out over the stop-bank and into the remaining
section of lake.
First a large hole was scooped out of the
original stop-bank and the dredge constructed in it.
Upon completion of the dredge the water was let in.
The dredge had a suction hose that drew water and
mud into it and along a floating pipeline and out into
what remained of the once-large lake.
While the dredge was being constructed the
As the lake bed was lowered, so did the water earth-moving machines were constructing a very long
level in the pond and eventually the pond was stop-bank enclosing the area to be exposed. This
drained, the dredge removed and tractor-driven basically completed the cutting off of the southern
Euclid's and the 120-B's were used to strip the section of the lake.
remaining overburden from the coal. Control gates were built in the northern bank to
At this stage even larger machines were control the inflow of water to keep the dredge afloat.
brought in from America called `Move-ails. The At intervals along the stop-bank there were suction-
wheels on these machines were 8-9 feet high and pipe stations that could be connected up to the dredge
new tyres for these and the TS-300s cost between as it moved around its pond. A cat-walk was built
500 to 1000 pounds. The smaller `carry-all' tyres along the top of the floating pipeline to give access
were just 300 pounds apiece. to the dredge as well as providing a support for the
By now there was a staff of 70 at the mine with diesel fuel pipeline to the dredge's motors and
4,000 tons of coal a day being removed but by 1962 pumps. This floating piece of machinery was serviced
the need for coal had dropped off and some scaling by a motorboat and a barge.
down occurred. The dredge still operated but it The cutting head on the dredge was on the end
would not be for very much longer as in 1968 it was of a long boom that could be raised and lowered and,
moved out onto the Waikato River as reported by the just to the rear of the cutting head was the vacuum
media: unit that drew up the resultant slurry.
As the dredging got deeper it was found
Shifting this 150 ton river dredge from necessary to add booster pumps to get the material up
the Kimihia open cast mine to the bank and over the dam. Also the dredge was stopped at
of the Waikato River at Huntly was the periodic intervals to remove the huge stumps and
biggest load ever moved in New Zealand, trees buried in the old lake-bed.
according to Mr W Sunde, transport The dredge was kept afloat by a sluice-gate in the
manager for Dale's Freightways Ltd, of dam regulating the flow of water back into the
Auckland. working pond.
As the lake bed was lowered, so did the water
Dales moves the dredge in a week-
long operation, ending with a four-hour, level in the pond and eventually the pond was
three mile journey early last Sunday drained, the dredge removed and tractor-driven
morning. Euclid's and the 120-B's were used to strip the
Combined weight of truck, trailers, remaining overburden from the coal.
pushing units and load totalled more than At this stage even larger machines were
200 tons, and measured 156 feet long, brought in from America called `Move-ails. The
32 feet wide and 24 feet high. wheels on these machines were 8-9 feet high and
On frequent occasion the trucks actually spun new tyres for these and the TS-300s cost between
away the gravel covering over the clay base of the 500 to 1000 pounds. The smaller `carry-all' tyres
hill and they could not progress until a bulldozer from were just 300 pounds apiece.
the mine came to assist them. By now there was a staff of 70 at the mine with
This happened far too often for the mine 4,000 tons of coal a day being removed but by 1962
management and a lower grade road was cut up the the need for coal had dropped off and some scaling
hill in an arc around the offending area. down occurred. The dredge still operated but it
The trucks still screamed their protests as would not be for very much longer as in 1968 it was
they crawled up and past the school but were moved out onto the Waikato River as reported by the
media:
uninterrupted in their journey.
In 1956 it was decided that a world first for Shifting this 150 ton river dredge from the
an opencast mine in dredging was to be attempted Kimihia open cast mine to the bank of the Waikato