Reclamation & Remediation

1. Railway corridors and creosote-treated ties

Coal-tar creosote is roughly 85 percent polycyclic aromatic hydrocarbons, with phenolics and nitrogen- and sulphur-heterocyclics making up most of the remainder. It has been painted, pressure-treated and leached into railway ballast and sleeper yards for well over a century. Benzo[a]pyrene and naphthalene are the names that appear on the regulatory schedules; the operational problem is broader.

The physics of a creosote site is the reason it appears on this page. Creosote is a dense non-aqueous phase liquid. It does not float and it does not dissolve away. It sinks through the water column and through permeable soil until an aquitard stops it, then pools there and feeds a dissolved plume for decades. Pump-and-treat chases the plume and never reaches the source.

A contaminant whose defining property is that it is denser than water is, by definition, a density-separation problem. Tie-disposal yards, derailment and spill sites, historic creosoting plants and the ballast beneath decommissioned track are all candidates.

2. Amalgamated silt — artisanal gold mining

Mercury amalgamation is still the dominant gold-recovery method for artisanal and small-scale miners worldwide, and it is the single largest anthropogenic source of mercury release. Elemental mercury is mixed into concentrate, the amalgam is burned off, and what remains — the amalgamated silt — goes into the tailings and, from there, into rivers.

Two things make this silt distinct. First, mercury and gold-bearing amalgam are extraordinarily dense compared with the host sediment, which makes them a textbook target for density-based recovery rather than chemical treatment. Second, once that mercury reaches anoxic river and estuary sediment, sulphate-reducing bacteria methylate it into methylmercury, which bioaccumulates up the food chain and is the form that reaches people.

Removing the dense fraction before methylation, and recovering the gold and mercury as sellable or securable product rather than waste, changes the economics of cleanup from pure cost to partial recovery. That is the case we want to test on a real deposit.

3. Sewage treatment and ocean outfalls

A great many coastal cities still discharge screened or primary-treated sewage through an outfall and rely on dilution to do the rest. The load is nitrogen and phosphorus — which drives eutrophication, algal blooms and hypoxic dead zones — plus the metals that industrial connections put into the sewer: cadmium, copper, zinc, lead and mercury, concentrated in the settled solids.

Biosolids are the mirror image of the problem. A treatment plant is very good at moving contaminants from the water into the sludge, and then the sludge has to go somewhere. Metal content and, more recently, PFAS are what stop that material from being applied to land.

Density-based separation is aimed at the solids side of that ledger: concentrating the metal-bearing fraction so the remaining organic material is worth returning to soil instead of landfilling. On the nutrient side, the answer is not a filter at all — it is vegetation that takes the nitrate up. See nitrates below.

4. Pulp, paper and tissue mill effluent

Making paper — including tissue and toilet paper — has historically meant discharging bleaching effluent into the nearest watercourse. Elemental chlorine bleaching of wood pulp generated dioxins and furans, including 2,3,7,8-TCDD, along with adsorbable organic halides, resin acids, black liquor carryover and a heavy biological oxygen demand. Modern elemental-chlorine-free and totally-chlorine-free bleaching has cut the ongoing discharge substantially. It did nothing for what is already lying in the sediment of receiving canals and river reaches, where fibre mats and the compounds bound to them persist.

A note on Love Canal, because it is often folded into this story and should not be. Love Canal in Niagara Falls, New York was not a paper mill. It was roughly 21,000 tons of chemical waste buried by Hooker Chemical in an abandoned canal excavation, capped, and then built over with a school and housing. The 1978 federal emergency declaration there is what produced CERCLA — Superfund — in 1980. It belongs on this page as the emblem of what buried industrial waste in a waterway costs a community, not as an example of pulp chemistry. Both are real. They are two separate problems.

5. Open-pit mines, spoil and disturbed slopes

This is where Breakthru reclamation seed has actually been used. Our root-development comparison photographs were taken at an open pit mine at Alix, Alberta, and our establishment photograph — ground covered fourteen days after seeding, over fist-sized rock — is from an Alberta Energy Corporation site. Slope stabilisation, competition against Downy Brome, and earlier release from site responsibility are the outcomes operators were buying.

The six reclamation claims

1. It provides the opportunity for reduced seeding costs because of the lowered or absent hard seed content and by reducing the dormancy factors.

2. It offers earlier establishment of the plant, providing resistance to spring die-off due to late frosts or early but insufficient water supply. G.E.M. treatment is particularly advantageous in fall seeding applications, where a true drought-hardened seed can establish faster than even a spring-sown G.E.M. seed.

3. Soil remediation is supported by the soil building characteristics of G.E.M. plants. The G.E.M. process sustains a viable symbiotic relationship between rhizobia and legumes for an extended period.

4. It produces a seed having higher vigour and a plant that demonstrates aggressive growth. This allows greater competition against weeds (Downy Brome) and the potential for earlier release from site responsibility.

5. It increases seed lot quality.

6. It greatly improves the stability of slopes due to the quick establishment of an extensive root system.

Germination trial — Red Top bentgrass

Cumulative germination, G.E.M.-treated seed against untreated control, counted at four intervals.

The treated seed reached a higher total germination, and reached most of it in the first four days. On a reclamation site that difference is the difference between a cover crop and an erosion event.

Low-temperature germination — for early and high-altitude seeding

The same seed lot run under five temperature regimes. Figures are cumulative percent germinated by day.

Tests conducted by Penn State University for Tee 2 Green Inc.

The 16 hrs @ 40°F row is the one reclamation contractors should read twice. At day nine the treated seed was at 93 percent and the control was at 30. Cold ground is the normal condition on a northern or high-altitude site in the only window the weather allows for seeding.

Seeding-rate reduction — reclamation species

Because a far higher proportion of treated seed establishes, less of it is needed. These are the published reductions against conventional rates — and on a reclamation contract, seed and its application are a large share of the per-hectare cost.

Field grasses

Wetland species and others

The wetland species matter here beyond their line in the table. Tufted hairgrass and tall mannagrass are the plants that go on the margins of a settling pond or a treatment wetland — the place where dissolved nitrate is actually taken out of the water.

Root development — the property that does the remediation work

Root biomass of G.E.M.-treated seed is up to five times that of untreated seed. That single property is behind most of what this page claims: slope stability, drought survival, competition against Downy Brome, nutrient uptake, and the soil building that lets a site be released.

Our root-development comparison was photographed on an open pit mine at Alix, Alberta — treated against untreated, ninety-day growth period. Our establishment photograph is from an Alberta Energy Corporation site, fourteen days after seeding, on ground scattered with fist-sized rock.

Yield demonstration — Legal, Alberta, 1996–1997

Run and measured by Legal Alfalfa Products Ltd. Algonquin at a conventional rate is the check, set at 100 percent. “Seeding diff” is the difference in seeding rate against that check — a negative number means less seed was sown.

The row that matters for a reclamation budget is AC Blue “J” (6) G.E.M.: 34 percent less seed sown, and it still out-yielded the check by 16.85 percent in 1996 and 43.70 percent in the first cut of 1997.

Trial conditions, as recorded: varieties were planted and yields calculated by Legal Alfalfa Products Ltd. All G.E.M. seed was inoculated but in bare form; all other seed was inoculated with a coating. The seed reduction factor per pound was calculated at 10 percent. This is a forage demonstration, not a reclamation trial — it is included because it measures the establishment advantage under field conditions with independently calculated yields.

Tree stimulant — for reforesting a closed site

Breakthru Tree Stimulant, 0-0-4, is 100 percent organic plant material, part of our Ecological Soil Management line. For a tree of three metres or more, each treatment is two 250 ml injections into the soil with a root feeder, placed on opposite sides of the tree at the drip line, with a root feeding time of ten to fifteen minutes. Shake well before use; apply after all signs of freezing have passed; may be harmful if swallowed; keep out of reach of children.

Where a reclamation plan ends in woodland rather than grassland — which is increasingly what regulators ask for — this is the establishment tool for the planted stock.