The Difference Between Rock and Rock

What’s the difference between the waste rock on the Ute Ulay site, and crumbling rocks on nearby parts of the Rocky Mountains?

Above is waste-rock at the Ute Ulay. Waste rock is a by-product of lode mining. The miners follow a vein through the inside of the mountain, searching for a rich ore that can then be processed and sold. After the rock has been drilled, and blasted with dynamite, the resulting material is mucked out (shovelled up and taken away). Next, the ore is sorted; the workers look for particular colours and types of rock that they know are mineral-rich. Those are set aside to be crushed, etc. and sold. The rest is waste rock.

Above are some naturally crumbly bits of the Rocky Mountains. The Rockies are geologically young, which means they are steep, and lots of bits of crumbly rock are still falling off them. It struck me that these crumbly rocks had come from the same mountains as the waste rock, were about the same size as the waste rock, and are heading into the rivers in the same manner that the waste rock does.

So what is the difference? The reason it matters, is that according to current practice here, waste rock requires remediation, whereas naturally crumbly mountain does not. If waste rock is part of the same mountain, and is the same shape and size as other crumbly bits of mountain rock, why are we not either:

a/ just ignoring it.

b/ remediating the entire mountain?

The reasons are twofold. Firstly, the waste rock has been taken from specifically mineral rich areas, and therefore has a higher mineral (potential pollutant) content. Secondly, the crumbly mountain rock has been subject to weathering forces which gradually erode it. So the waste rock is leaching out more minerals, at a faster rate than the naturally crumbling rock. That creates the potential for risks to human health, amongst other things.

There is lots of waste rock up at the Ute Ulay. Part of the process of developing the Ute Ulay site will be to keep people’s contact with the metals present there (lead mostly) to a minimum. After a meeting this morning with representatives from CDPHEDRMS, and Colorado Brownfields Foundation, I have a few things to ruminate on regarding the future shape of the Ute Ulay.The remediation strategies proposed for the Ute Ulay would drastically alter some of the historically important landform.

There is no doubt that the landscape will change significantly. But this is just another stage in the history of this place. It is also an opportunity.

As a landscape architect I am regularly (partly) responsible for changing places. I remember the first site visit I ever went on. It was to a run-down victorian seaside resort called Rhyl in north Wales, and I felt the weight of people’s memories weighing down on me. Who was I to propose any changes?! But it’s part of the job to develop the confidence to alter places – you just hope that you can make it better for most people.

A year after the park in Rhyl was completed, I went back to check on the planting and overheard people telling each other how much they liked the place. It meant more than any award ever could.