Listen to the Hill Truck — Use Radio Scanner

One of the famous hill trucks.

One of the famous hill trucks, parked at loadout. Note the huge tires, every one chained up. Those blocks weigh thousands of pounds.

We would not have the Quarry Road for winter use if it wasn’t for the operating Yule Quarry business. Tradeoff is that most weekdays and sometimes on the weekend a huge “hill haul truck” loaded with gigantic blocks of white marble is making multiple runs up and down the mostly one-lane shelf road. We have to be as nice as possible to these guys while they’re running the truck. It’s dangerous to just blunder up and down the road, expecting to somehow get by the hill truck (or for that matter, other quarry business traffic). If an accident happened, that could be fodder for the road being closed to public traffic.

How to not blunder? Firstly, prepare at home. During snow and mud seasons, you should only drive Quarry Road (County Road 3) with all-wheel-drive or 4-wheel-drive. Your vehicle must have aggressive snow/mud tires that are in good condition, or tire chains on at least one pair of wheels (with a 4×4, you usually chain the front wheels to maintain steering control). Also prepare by calling Colorado Stone Quarries at 970-704-9002 and inquiring for road conditions. The Quarry has posted on their Facebook that they welcome phone calls about road conditions.

When driving Quarry Road, pay attention to all zones where you could pull over to let the haul truck pass on the INSIDE (due to possible soft shoulder on the drop-off side). If you encounter the hill truck, immediately reverse to one of the spots you memorized. The truck has right-of-way in either direction. The need to park tightly on the side of the road to allow the hill truck to pass is the main reason you need all-wheel-drive and good tires. This is serious stuff that involves your own personal safety as well as that of the Quarry employees. What is more, if the road situation becomes difficult to manage, the road could be closed to public use. Thus, driving with care and using the correct equipment is not only a safety issue, but could be an access issue.

Better still: During winter, the quarry avalanche safety plan requires their vehicle operators to radio their locations on the road while they’re driving. This is done using a basic 2-way business radio system that’s easy and legal to scan. Implement a couple of tricks and you can easily know if the hill haul truck is moving up or down the road, as well as the truck’s approximate location.

A. Get a scanner. Here are the frequencies used by the quarry business:

461.500 (used by drivers and other quarry workers)
466.500 (this seems to be the best frequency to monitor for haul truck locations)

We’d advise scanning all these frequencies now and then, as well as a wider scan to determine if other radio systems are being used by the quarry. More, when setting up some more complex scanners be sure to look for frequencies that use CTCSS and DCS codes as well as repeater systems — scanner documentation will make this clear.

B. Learn the names of the 14 or so avalanche paths and locations (see map and observe) that the quarry drivers may note on their 2-way radio as they travel the road. Below is an approximate list, to be updated. Starting from the town, mileages are from bridge a few feet past loadout and quarry office, downhill and uphill edges of paths. Original quarry avalanche consultant Chris Landry named and mapped most of the avalanche paths, this data originates from his early mapping. Please know these are not all the possible places various sized avalanches could fall on the road, and the mileages will vary according to your own speedometer calibration as well as being rounded to the nearest one tenth mile.

1. Loadout (stone yard in the town of Marble.) 0
2. Carbonate (first huge avalanche path that crosses road, at sharp turn) .2 – .3
3. Subaru Flats (Steep loose shale bank above road, named after a Subaru that was once buried here.) .8 – .9
3. Monument (somewhat hidden avalanche path, comes down through aspens) 1.2 – 1.4
4. Shale Cut (narrow section with rock wall, turnouts above and below) 1.4 – 1.5
5. No Name (obvious) 1.6 – 1.7
6. Alley (long section of road, with bowls above) 2.1 2.3
7. Pre Mud (steep mountainside with sparse aspens) 2.3 – 2.5
8. Mud Gulch (narrow gully, just before most common parking spot) 2.5 – 2.6
9. Marble Banks (various bank sluffs, uncommon) 2.7 – 2.8
10. Marble Peak (road feature is “Lumber Curve,” has not run big in years due to skier compaction) 2.8 – 3.0
11. Windy Corner (last sharp curve before you reach the quarry gate) 3.1
12. Portals (quarry)

In our observation, some of the truck drivers are easy to understand, and some are not. More, radio reception will vary by location. If you get poor reception with scanner, purchase and install a mag-mount antenna on your car roof. The antenna shown at right is an example. If purchased, attempt to find a radio communications consultant who can “tune” the antenna for you so it performs better for the quarry frequencies (though it’ll still be an improvement as stock).

Check out this scanner review, tested for Quarry Road, works well.

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  1. Got this up a few days ago, been testing the radio. Works well when the quarry employees remember to transmit their locations while driving the road. They’re usually pretty good about it, though hard to understand.

    Note you can also simply stop at the quarry loadout and ask where the hill truck is, they’ll let you know and you can time your drive accordingly.

  2. We’ve been working our radios, it appears the simple way to listen for hill truck positions on road is to monitor 466.500.

    • Brandon on April 3, 2018 at 9:25 pm

    Do any of the freq require CTSS or DCS codes? Also are they on 12.5 or 25 Khz bands?

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