How CCME soil guidelines apply to Ontario site assessments
When a Phase II Environmental Site Assessment turns up petroleum hydrocarbons in soil, the next question is almost always: which CCME table applies? The answer depends on land use, and getting it wrong at the sampling stage means either over-remediating a site or submitting a report that a regulator will send back. This article walks through the key distinctions.
The four land-use categories and what they mean in practice
CCME's Canada-Wide Standards for petroleum-contaminated sites define four land-use categories: agricultural, residential/parkland, commercial, and industrial. Each carries a different set of numeric criteria for PHC fractions F1 through F4. The category is determined by the current or planned use of the site, not by what the surrounding neighbourhood looks like.
In Ontario, the Ministry of the Environment, Conservation and Parks (MECP) has adopted CCME standards as the basis for its Records of Site Condition (RSC) process, but with some Ontario-specific modifications. If you are working toward an RSC, confirm with MECP's current guidance document which version of the CCME table is in effect. The standards were updated in 2008 and Ontario's adoption of specific revisions has not always been simultaneous.
PHC fractions F1 through F4: what each covers
The four PHC fractions are defined by carbon chain length and boiling point range. F1 covers C6-C10 (gasoline-range compounds), F2 covers C10-C16 (diesel-range), F3 covers C16-C34 (heavier fuel oils), and F4 covers C34-C50 (lubricating oils and heavy residuals). Each fraction has a different mobility in soil and a different toxicological profile, which is why the criteria differ.
Laboratories report these fractions by GC-FID after solvent extraction. The extraction solvent and cleanup procedure matter: if a lab uses a method that does not adequately separate F1 from the F2 fraction, the F1 result can be artificially elevated, which affects the comparison against the criterion. When reviewing a lab report, check that the method citation matches the CCME reference method or an equivalent validated procedure.
- F1 (C6-C10): gasoline, light naphtha, some solvents
- F2 (C10-C16): diesel, jet fuel, kerosene
- F3 (C16-C34): fuel oil, heavier distillates
- F4 (C34-C50): lubricating oils, heavy residuals
Practical notes for sample submission
Soil samples for PHC analysis should be collected in pre-cleaned glass jars with Teflon-lined lids, filled to minimise headspace, and kept at 4°C from collection to delivery. Holding time from collection to extraction is 14 days for F2-F4 and 7 days for F1. If your field schedule is tight, contact the laboratory before you go out so the extraction can be scheduled immediately on receipt.
Including BTEX (benzene, toluene, ethylbenzene, xylenes) as a companion analysis to PHC fractions is standard practice for petroleum-release sites, because BTEX compounds fall within the F1 range but have individual health-based criteria that are more stringent than the bulk F1 criterion.
If you are unsure which CCME table applies to your specific site or whether Ontario's current RSC guidance modifies the standard criteria, bring that question to the laboratory at intake. It affects which method we run and how we structure the report.