We have at our disposal proprietary ground improvement tools and techniques which can help mitigate some environmental concerns. Our machines are modular so that we can decide which assembly is best suited to the special conditions at each individual site. We call the basic configurations: the Phoenix™ Machine; the Trident unit; and, the Strata Mixer. The following are three common problems, and our suggested solution.
The mining industry, apart from whatever ground needs disturbing because it gets in the way of digging out the ore body, also needs fairly flat land nearby on which to pile the leftover tailings. In most cases the volume of these wastes far exceeds the volume of the extracted ore body.
Here are three way our IP could help:
1. The very fine particulate "slimes" can be reduced in volume by homogenization of the separate layer and lenses within their mass; our Strata Mixer has be specifically designed for that purpose.
2. The coarser (sand-sized) tailings can be reduced in volume by using our hydrodynamic vibrator to force the individual particles into taking up a denser packing arrangement.
3. The footprint occupied by the tailings dam can be minimized by providing a competent tailings' foundation so that subsequent crest lifts can be built by the "upstream" construction method.
Our Trident hardware can withdraw contaminated water (or light fluid) from below the water table and replace it with clean water. The current machine is intended for working at depths of up to about 25m (~80 feet) in sandy soils such as deltaic sediments or mine tailings; it is not designed to penetrate rock, glacial drift, or highly cohesive deposits.
It consists of 3 vertical and parallel tubular pokers which penetrate to the bottom of the contaminated ground. Each poker has a two-way fluid pump and a vibrator close to its nose cone (tip), all of which can be activated separately. Thus, for instance, two pokers might be set to pump water/fluid out of the ground, while the other replaces the dirty fluid with clean water. In that way the triangular area within the compass of the Trident can be rendered free of contamination. It is obvious that the water being pumped into the ground could initially contain a solvent to facilitate the cleansing circulation; and also, the replacement water could be a recirculation of previously withdrawn groundwater that had subsequently been purified.
Once the groundwater was treated at the lowermost level of contamination then the assembly would be gradually withdrawn upwards, so that the process could be repeated at each increment of elevation, thereby exposing the full depth of the aquifer to cleansing.
The expression "the Gift of the Nile" referred to Egypt in Roman times, and that was because each year the floodwater spread a new layer of fertile silt along the Nile valley and over its delta. So that this land beside the Sahara desert was able to feed its own huge population, with enough left over to trade for luxuries and idle time.
From where I am sitting I can see the Fraser River carrying it own sediments into our Delta. But sadly I've also seen this, our "gift", being ignorantly destroyed and lost forever by old-fashioned "ground improvement" technology. Current/standard practice is to first bury the fertile silt stratum beneath a huge pile of pre-load sand, and once all the fecund void spaces have been squashed, then as a final insult to Mother Nature, to import crushed rock from the quarries on nearby Texada island and stuff those broken bits down holes water-jetted through the dying silt layer. This is needlessly distructive.
The alternative is: Take out the living silt and spread it over the local tracts of farm land which suffer from seasonal flooding. Fill the excavations with the deltaic sands (available in abundance) and then make this continuous sand foundation as dense as you like by vibration. This is easily done with available equipment. Assiduous use of temporary sets of retrievable lightweight sheet piling to contain the excavations will make for simple implementation.