SUBMISSION ON PROPOSED…

SUBMISSION ON PROPOSED REGULATORY CHANGES FOR THE BENEFICIAL REUSE OF EXCESS SOILS AT PITS AND QUARRIES IN ONTARIO
In establishing regulations for the beneficial reuse of excess soil the following aspects must be given attention:
1. Excess soil to be reused comes almost entirely from urban areas. Most urban soil contains some quantity of deleterious substances such as petroleum hydrocarbons, volatile organic compounds, metals, polycyclic organic hydrocarbons, polychlorinated biphenyls, per-and polyfluoroalkyls.
2. Soils with no exceedances of MECP Table 2 Standards, nevertheless, have, on average, higher concentrations of one or more of these substances than the soil in undisturbed rural settings that form the principal groundwater recharge areas in Ontario.
3. As a result of the difference in contaminant level between surplus urban soil and undisturbed rural soil, depositing “clean” surplus urban soil into groundwater in a water filled pit or quarry will almost always cause a deterioration of the quality of groundwater – a definite disbenefit.
4. Given the high spatial variability of contaminants in urban locations it is extremely difficult to detect all the contaminated soil present. Even with the most careful sampling protocol some contaminated soil will be classified as “clean”. The presence of some contaminated soil mixed among generally clean soil results in much enhanced risk that allowing the depositing of excess urban soil in groundwater will result in appreciable groundwater contamination.
5. There is an unfortunate history of illegal disposal of contaminated soil in Ontario. There is a large financial incentive for those involved in urban development projects to minimize the costs associated with proper legal disposal of contaminated soi by avoiding proper sampling for detection of contamination or by misdirecting contaminated soil to low-cost disposal sites. The risks associated with disposal of excess soil in pits and quarries is thus very high unless such disposal is subject to constant and comprehensive scrutiny by independent inspectors.
6. Groundwater in Ontario is regarded as a common good not subject to ownership and managed by the Province for the benefit of all residents and the natural environment. The Water Resources Act prohibits any actions that involve allowing contaminating substances to contact water. Meeting the responsibility of sustaining the quality of this common good requires great care by the Province in the supervision of disposal of excess urban soil.
7. The recommendations of the Walkerton Inquiry included the requirement that in every Sourcewater Protection Area any pit or quarry that breached an aquitard should have the protection afforded by a restrictive aquitard layer restored before the rehabilitation of the pit or quarry was approved as completed. This recommendation has not been implemented in Ontario.

Taking these considerations into account the following general principles apply:

8. The best assurance of protection of the water quality of groundwater from the presence of contamination in urban excess soil is to require the excess soil to be deposited on dry land at least 2 m above the seasonal high watertable and prohibiting deposit of any excess soil in standing water. The Precautionary Principle dictates that this be the policy adopted.
9. If for economic or other reasons there is justification for risking groundwater contamination in order to reduce the costs of disposal of excess urban soil or to recreate dry-land surfaces for future use the disposal of excess urban soil in water-filled pits and quarries should be limited to a few large carefully selected and carefully licensed sites.
10. The most important rule for the licencing of a water-filled pit or quarry for disposal of excess soil is that no licenced site should be allowed within, or immediately adjacent to, a Sourcewater Protection Area.
11. Every site licenced for water disposal should be required to have an independent inspector present at all times to verify the origin of each load as coming from a fully approved site with clearance for clean fill disposal and to conduct surface scans of each entering truck for volatile hydrocarbons.
12. Every licenced site must have a water-quality montoring system including a set of monitoring wells surrounding the site to establish the water quality of the water in the pit and of the groundwater entering and leaving the site in the lateral flow and any changes in the water quality occurring with time.
13. Every site licenced to accept excess urban soil for disposal into water should be required to hold insurance against the occurrence of specified forms of groundwater contamination resulting from the disposal of the excess soil at the site.
14. Every licenced site must have an approved final site plan for rehabilitation that includes a requirement to have the final ground level at the site to be 2 m above the seasonal high watertable. The site owner should be required to provide financial assurance that the site will remain active until this final rehabilitation status has been achieved.
The basic direction of these suggested regulations is to provide assurance that only large, well financed , and carefully supervised sites be used for water-contact disposal of excess soil. And that only soil from large, well financed and carefully supervised construction sites be used for water-contact disposal.
I include an example of site condition assessment that shows in a small way how great diligence is required to properly assess the condition of excess urban soil.
The proposal to provide approval for ALL water-filled pits and quarries to accept excess urban soil as fill is a recipe for disaster and is an open invitation for illegal dumping as evasion of the rules is easy given the inadequate funding of enforcement. Only by limiting approval to a few highly supervised and monitored sites can groundwater quality protection be assured.