Comments on the document…

Comments on the document entitled: "Rationale Document for Development of Excess Soil Standards".

1 ) Section 4.2 – Selection of Appropriate Standards Tables: The Site Condition Table in this section shows that the shallow soil condition standards Tables 6/6.1 and 7/7.1 are to be used in situations where the depth to groundwater is unknown, less than 3 m below grade or within 0.8 m of the gravel crush of a building. It’s understood that under these conditions the S-GW2 pathways in the Table 2/2.1 and 3/3.1 standards may not be conservative enough for protection of the inhalation pathway. However, the shallow soil condition standards may be overly conservative for non-volatile parameters on shallow groundwater Sites due to the absence of dilution considered in the development of the Table 6/6.1 and 7/7.1 S-GW3 values. Can clarification be provided that the Table 6/6.1 and 7/7.1 standards only need be applied to volatile parameters at shallow groundwater sites that are located greater than 30 meters from a waterbody.

2) Section 4.2 – Selection of Appropriate Standards Table: Table 5/5.1 and Table 6/6.1 are marked as not applicable under the scenario where excess soil may be placed at any depth. Can you please provide clarity about why Table 6/6.1 would not be applicable in this case, or confirm that this is an error, and Table 4/4.1 should be marked as inapplicable instead of Table 6/6.1?

Comments on the Draft On-Site and Excess Soil Regulation and Draft Rules for On-Site and Excess Soil Management.

3) The term “Project Leader” is used throughout the documents. This is a new term not used in previous excess soil documents and not used in related regulations (such as Ontario Regulation 153/04) and therefore, not well defined. We recommend use of terms that are already well established and clearly defined in this sector. The ultimate decision maker and ultimate responsible party is the entity funding the project. Therefore, we believe terms such as the Property Owner, or potentially Project Owner (where the property owner is not responsible for or funding the project), and/or Agent for the Property or Project Owner would be more clearly understood and clearly define who is ultimately responsible.

Comments on the Draft Rules for On-Site and Excess Soil Management.

4) We believe the document would benefit from a decision tree or flow chart or some illustrative schematics to assist with understanding the various steps to be followed and the basis for deciding on various exception/exemption pathways.

5) Leachate Test Requirements: The proposed Soil Rules rely on laboratory Leachate Tests to assess whether contaminants might leach from soil. They do not include an allowance to consider actual groundwater quality results from a site. We believe that, if available, consideration of actual groundwater quality results should be allowed in the decision process about whether a soil is acceptable for reuse at another site, if the QP can show relevance. For example, consider the following situation (based on an actual project). (1) A site located in low permeability clayey silt soils (which are very common in Ontario). (2) Soil quality at the site meets the relevant criteria. (3) Groundwater exceeds the relevant criteria for a chlorinated solvent. (4) Client wants to remediate site. (5) Due to the low permeability of the soils, management of groundwater through pump & treat or in-situ treatment is not practical or prohibitively expensive. (6) Risk assessment was not considered acceptable to stakeholders (financial, insurance and interested purchaser) (7) Most reasonable option is to excavate the soil containing the contaminated groundwater. (8) Laboratory leaching tests do not exceed the criteria proposed in the draft rules, suggesting soil can be reused at another sites. (9) Actual site specific groundwater results indicate that the soil is likely to cause groundwater contamination, if placed at another site, and therefore should be disposed at landfill or processed. (10) Discrepancy between actual groundwater results and laboratory leach tests due to difference between complex field conditions and more simplified lab conditions. Actual groundwater results should be considered in decisions about whether soil is acceptable for reuse.