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The Ontario Ministry of the Environment and Energy (MOEE) released its new Guideline for the cleanup of contaminated soil and water on June 20, 1996, entitled Guideline for Use at Contaminated Sites in Ontario. With the release of this document two significant changes will occur in the way contaminated sites are cleaned up. The MOEE will become less involved in cleanups and the cleanup levels for some petroleum produces have been made less stringent. Cleanup levels for over 100 other substances are also given whereas only a few dozen were formerly available.

The Guideline provides three different methods of determining cleanup criteria. The most involved method is site specific risk assessment, involving human health and ecological risk analysis. This involves scientific study and public consultation and would be too expensive and time consuming to be applied to residential fuel oil spills. The background approach involves comparison of the contaminant parameters to measured background levels in Ontario. In most cases, soils in the immediate vicinity of a fuel oil spill will exceed the background levels. Therefore, the generic criteria approach will be used for fuel oil (and most other) remediations.

Although this is just a guideline and the legislative and regulatory duties of the MOEE are not changing, the MOEE is withdrawing from the review and approval of typical cleanups such as those arising from residential oil spills. From discussions with government staff, I understand that the MOEE will only become involved in cases where there is an "adverse environmental impact", which on a practical basis for petroleum contamination means the pollution of a drinking water well. The Fuels Safety Program of the Ministry of Consumer and Commercial Relations is also expected to take a more hands off approach, following the lead of the MOEE and due to budget restrictions. Spill reporting requirements have not changed.

The new document contains some significant changes in the form of less stringent criteria for the cleanup of some petroleum products compared to the MOEE's Proposed Guidelines for the Cleanup of Contaminated Sites in Ontario, which was released for public comment in July 1994. Examples of the new levels are presented below along with the 1994 proposals and the previous criteria for similar circumstances.

Another change from the original proposals is the use of two different cleanup criteria for the same chemical based on soil texture (coarse vs. medium/fine). Benzene is the example shown in the table below.


New Guideline

1994 Proposed

Interim Guidelines for Petroleum Contaminated Sites in 1993

TPH (gas/diesel) in soil Residential land use Non-potable water area

1000 ppm

100 ppm

100 - 1000 ppm depending on side factors

Benzene in coarse grained Soil residential and use Non-potable water area

5.3 ppm

0.05 ppm

0.05 - .2 ppm depending on site factors

Benzene in fine grained soil Residential land use Non-potable water area

12 ppm

0.05 ppm

0.05 - .2 ppm depending on site factors

TPH (gas/diesel) in Non-potable water

No value

50 ppm

No value

TPH (heavy oil) in soil Agricultural land use, Potable water area

1000 ppm

100 ppm

1000 - 5000 ppm

Notes: groundwater is used for drinking in potable water areas. Built-up urban areas served by municipal water distribution are usually non-potable water areas. TPH: Total petroleum hydrocarbons


Contaminants in fine textured soil are less available for uptake by plants and animals and thus the cleanup levels are less stringent. The medium/fine criteria will be used at many sites since this has been defined as any soil with less than 70% sand sized (50µ) particles.

As in the proposed Guidelines, stratified depth clean-ups are allowed. Cleanup criteria for soil located 1.5 m or more below grade are significantly less stringent than the full depth values. For example, the stratified TPH value for residential land use in a non-potable groundwater situation is 5000 ppm whereas the corresponding full depth value is 1000 ppm. The stratified depth criteria are applicable to the cleanup of basement spills. The Guideline specifically states that when the stratified depth values are used "vapour movement from contaminated soil or groundwater will not adversely affect air quality where living space is located above or below the 1.5 m level". Furthermore, the Guidelines state that, "an additional 1.5 metre envelope of surface soil quality is not required below a basement floor".

The stratified clean-up Guidelines will reduce the cost of the clean-up of basement fuel oil spills, where they are applied. Unfortunately, from the insurer's and insured's point of view there is significant drawback to the use of the stratified depth criteria. A notice on the land title, called a "Certificate of Prohibition" must be put in place. This will reduce the resale value of the property and/or may lead to difficulties in obtaining future financing for the property.

In summary, the new Guidelines provide for the following:

• Clarity in the required clean-up criteria

• Absence of MOEE involvement in routine cases

• Less stringent petroleum product clean-up criteria in some cases

• Possibility of stratified depth cleanup

The information contained in this web site is intended for marketing purposes only. It is not all-inclusive, and does not fully describe the many and varied services that the company provides, nor does it completely describe the education, training, skills, or expertise of our staff.


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