the photos in the above artcle were taken by me during a research
trip to the Henderson Mine
last run of the Henderson Mine railroad took place July 30,
1999 marking the end of a little known but unique industrial
railroad. The Henderson had one of the longest rail tunnels
in world and only its remote location in the Rocky Mountains
kept it out of the spotlight. This heavy haul, electrically
powered railroad transported more than 150 million tons of ore
during its 23 year life. It has since been replaced with the
world's longest conveyor belt operation but not before achieving
some remarkable statistics.
Climax Molybdenum Company, operator of the Henderson mine and
part of Phelps Dodge Co., was chartered to develop the deposit
of molybdenum which was discovered in 1964. The ore body is
located inside Red Mountain near Empire, Colo., about 50 miles
west of Denver. Molybdenum or "Moly" as is it more
commonly called, is a basic ingredient in certain types of steel,
automotive airbags, a smoke retardant in plastics and fibers
and is used as a catalyst in oil refining.
of the deposit began in 1970 and by 1976, production had started.
The initial work was at the 8,100 foot level and it, along with
the now exhausting 7,700 foot level were served by the mine
train operation. The levels of elevation are based on sea level.
The mountain is laterally mined from the top down and the inside
rail line was the engineer's answer to the question of how
to move molybdenum ore from a mine inside Red Mountain to
a processing mill about 14 miles away on the other side
of the Continental Divide. Given the tonnage to be moved
and distance to be covered, a railroad was the only real
answer. The rail operation required a tunnel under the Continental
Divide that is 9.8 mile long, longer than either the BNSF's
Cascade tunnel or the Union Pacific's Moffat tunnel. One
source ranks the Henderson tunnel is 10th longest in the
the decision was made to build the railroad, selection of power
and equipment was next. With a 9 mile tunnel, diesel power was
not practical unless an expensive ventilation system would have
been used. The density of train operation also made diesels
undesirable since the trains would be manned and the fumes would
have been dangerous.
Sweden's ASEA was chosen to supply 32 electric engines or "locis"
as they are called by the Henderson personnel. Each loci weighed
55 tons and rode on two axles. The technology used was based
on the rail equipment used in Europe and the gauge chosen was
42 inch, similar to that of many European lines. Catenary style
overhead was used and the engines were dual voltage operating
on both 1,400 volts and 600 DC volts. For safety reasons, given
the close clearances inside the mine, voltage in the loading
areas was limited to 600. The trains used disc type air brakes
along with dynamic braking, a common feature on electric operations.
also rostered 3 small diesels which were used for work trains
as well as for movements over the small amount of non-electrified
trackage. One of these was retained after the electric operation
was shut down. The conveyor is bolted to the outbound track
and the inbound track is retained in the tunnel for maintenance
purposes. This diesel will be used as needed.
250 20-ton ore cars were also purchased and these also rode
on two axles as did the engines. The cars are dump bottom and
used a unique unloading system. As the cars passed through the
unloading facility, they were suspended on wheels mounted on
each side of the unloading pit. A flange on each side of the
car rode on the wheels. This allowed a wide open dump pit, unhindered
by rail or supports.
guide rail under the cars opened and closed the bottom of each
car allowing complete unloading to be done very quickly. Even
the engines were equipped with these flanges so they were also
momentarily suspended over the pit. With locis at both ends
of the train, continuous movement was possible.
line was double track with a series of loading tracks
at the mine and a small yard behind the unloading building
at the mill. The track was originally a combination of
90 and 115 pound rail but the lighter rail was gradually
replaced with the heavier rail over time on the outbound
track. The track in the tunnel was mounted on a concrete
slab with pandol plates and clips. The outside track was
on conventional wood ties.
track in the tunnel is on 3 percent grade and this presented
some real operating problems. The grade was against loaded
trains and because of this, the rail actually flowed or
stretched downhill towards the mine. There was a special
switch at the bottom of the grade which allowed the rail
to stretch and the excess rail was periodically trimmed.
combinations of engines and cars were used until a pattern
of 3 locis on one end and two on the other spliced by
30 cars became standard. Top speed was about 25 miles
per hour and the round trip took about two hours.
1996, each train had an operator until an automated system
was installed. The original automatic block signal system
was incorporated into the new system. 3000 foot loops
of wire were installed between the rails along with radio
equipment on each locomotive. The system detected the
speed and direction of each train while maintaining proper
equipment was extremely durable and the locis had an availability
rate in the high 80 percent range. The typical operation of
the mine was 24 hours, 5 days a week and the trains had to keep
moving if the mine and mill were to function economically. Nearly
all the cars and engines were still in service on the last day
attesting to the quality of equipment and care and maintenance
provided by the Henderson railroaders.
the ore at the 7,700 foot level became depleted, the continued
operation of the railroad came under review. The new producing
level, located at 7,175 feet or nearly 400 feet below the train
level, is too far below railroad to make continued operation
possible. The ore would have to have lifted up to the level
of the train whereas before the ore was dropped down to the
train for loading.
options were considered before the conveyor system was
chosen. Routing the trains down to the new level would
have required a steep spiral grade which would have been
beyond the ability of the trains to negotiate. Another
plan involved a conveyor from the new level up to the
trains but it was also impracticable. Another plan would
have used a conveyor from the mining level to the entrance
of the tunnel where the ore would have been transferred
to the trains for movement the crusher.
final determinate in deciding to replace the rail line
with a conveyor system was the age and condition of the
cars and locis.
were dealing with 1960 technology and parts were becoming
increasingly difficult to obtain," said Jim Mahon,
Maintenance Superintendent. Mahon indicated that they
also looked into replacing the existing equipment and
the cost of the trains and conveyor belt came in about
the same but the maintenance expense for the belt was
less than the railroad.
the decision was announced the Henderson staff allowed
the Rocky Mountain Railroad Club the opportunity to make
two visits to the railroad and photograph the above ground
operation. A film crew was allowed to videotape the entire
operation including cab rides in the locis.
the trains were shut down, the Henderson staff donated
a loci and a mine car to the Western Museum of Mining
and Industry in Colorado Springs, Colo. In addition to
donating the rolling stock, the Henderson donated the
transportation to the museum as well. Future plans call
for the loci and car to be displayed on a section of track
under catenary so it will look as it did when in service.
Another loci and car have been preserved at the entrance
to the mill complex.
the conveyor belt is more efficient and cost effective, it is
a safe bet that no one will feel about it as they did about
the Henderson mine tram.