Re: Why Wooden Sleepers are better. Was [NSW] CityRail Delays Friday

[eikkert@my-deja.com]

>> Now what is more environmentally friendly, a soft wood treated with
>> copper-cynaide, a hard-wood from a tree that took 100 years to grow,
>> or a concrete sleeper made out of 'dirt' dug up out of the ground.
>> Given how much longer the concrete ones last, even with all the
>> mining involved, they probably come out ahead in the 'greenie'
>> stakes!.
>
> And concrete can be recycled.

I think that is a bit short sighted. Concrete can be recycled but not
very efficiently same with wood. I'm not really sure what recycling
entails, I'm guessing that it's merely crushing up the concrete and
using it as aggregate (like recycling high grade refractories into lower
grade refractory bricks) rather than reforming.

But as you did mention, trees take 100 years to grow whereas some of the
ingredients in concrete may be virtually considered as unsustainable
resources. Future planning can be done to ensure a sustainable supply of
wood for railways, however I don't think you can do the same for sand
and lime movements. Once it's taken, it's taken you can't replant sand
or limestone for future collection.

> Whatever the case, it has to be better than a 6 lane freeway.

Yes, you will get no arguments here.


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