Ontario Regulation 406/19 and hydrovac slurry

What the regulation is

Ontario Regulation 406/19, On-Site and Excess Soil Management, is made under the province's Environmental Protection Act. It's supported by a companion document, the Rules for Soil Management and Excess Soil Quality Standards, which holds the detailed technical requirements.

The regulation came into force in phases starting January 1, 2021. Its purpose is to treat excavated soil as a resource to be reused where it safely can be, and to stop soil from being dumped where it shouldn't go.

Where hydrovac slurry fits

Hydrovac slurry is liquid soil, which Ontario's guidance describes as often generated through hydro-excavation. Once soil leaves the area where a project is being carried out, it becomes excess soil under the regulation, and the rules on where it can go and how it's documented start to apply.

Excess soil that's managed improperly and deposited somewhere it shouldn't be is treated as waste, and the ministry can require whoever caused or arranged the deposit to remove it and dispose of it properly. That's why the destination of a hydrovac load matters.

Options for liquid soil

Broadly, a load of liquid soil can go down one of these routes:

• A reuse site that's authorized for liquid soil. Liquid soil can only be accepted at a reuse site when a site-specific instrument, such as a municipal by-law or an approval, allows it.
• Dewatering or solidifying, then reuse as dry soil. Ontario's guidance recognises drying out liquid soil so it can be reused as dry soil, subject to the quality standards for the reuse site.
• An approved receiving and processing facility. A facility operating under an Environmental Compliance Approval, like EcoVac, receives the liquid soil and handles it under the conditions of that approval.

Some of these routes carry their own conditions or need additional approvals, so the right one depends on the project.

The landfill restriction

Ontario's excess soil guidance sets January 1, 2027 as the date from which cleaner excess soil is restricted from being landfilled. Specifically, excess soil that meets the Table 2.1 standards, the cleanest generic standards for residential, parkland and institutional use, can't be deposited at a landfill or dump. There are exceptions, including soil a landfill needs for daily or final cover.

The start date was originally January 1, 2025 and was moved to give industry more time. The direction hasn't changed: soil that could be reused is meant to be reused.

Records, tracking and exemptions

For many projects the regulation brings requirements around sampling, planning where excess soil will go, tracking loads and keeping records, including filings in Ontario's Excess Soil Registry for projects that meet the thresholds. Some projects and activities are exempt from some of these requirements, for example certain small volumes going directly to a waste disposal site, emergencies and some infrastructure maintenance work.

Because exemptions are specific, it's worth confirming how they apply to a given job rather than assuming.

Municipal by-laws

Municipalities can regulate site alteration and the placement of fill through their own by-laws, and those rules can go further than the provincial regulation. If a load is headed for reuse at a site, check the local by-law as well.

Where EcoVac fits

EcoVac is a receiving and processing facility operating under Ontario Environmental Compliance Approval No. 3168-BH9JQY. We receive non-hazardous liquid soil from hydro-excavation and separate it into stone, sand, clay and treated water, so more of each load has a reuse route. About our approval or how disposal at EcoVac works.

Common questions