Wellsite Remediation in Crossfield, Alberta | In-Situ Chemical Oxidation (ISCO) Case Study

Case Studies

Wellsite Remediation in Crossfield, Alberta | In-Situ Chemical Oxidation

Project Details:

Location:

Wellsite - Crossfield, Alberta

Site:

Oil and Gas Site (Flare Pit)

Date:

2009

2017

Present

Contaminant of Concern:

BTEX, C6-C16

Impacted Media and Volume:

80,000 m3 impacted soil and groundwater

Project Tasks:

Detailed site assessment, Hydrogeological characterization, Remedial planning, Detail design, Procurement, Blending and Field applications

View Project Images & Details →

The Problem:

Former flare pit area overlying shallow fractured bedrock. Condensate (BTEX) contamination dissolved in groundwater covering 21,000 m2.

The Approach:

Conduct detailed geological/hydrogeological investigation to identify fracture pathways and contaminate transport.

In-situ chemical oxidation (ISCO) program based on 15 meter injection radius of influence. Establish health and safety protocol and site logistics for handling oxidizer.

Installed 90 injection wells, and injected over 100,000 litres of blended 17% EHP (enhanced hydrogen peroxide) oxidant. Blending is site specific following TRIUM’s ChemOx® process.

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The Results:

Plume area reduction by >90%
Highly cost effective compared to traditional remedial options, with minimal carbon footprint
Excellent reductions noted with injection distributions exceeding planned performance
Follow-up program for completion of impacts in source area

Pipeline Release Remediation in Central Alberta: A Risk-Based ISCO Case Study

A pipeline release site in Central Alberta faced residual petroleum hydrocarbon contamination (BTEX, F1, F2) that could not be fully treated with a multi-phase extraction system. Due to site lithology, a risk-based in-situ chemical oxidation (ISCO) approach was implemented with a 1.5 to 2.5 meter injection radius, installing 12 injection wells and injecting 6,500 liters of 12% EHP (enhanced hydrogen peroxide) followed by 3,700 liters of 15% sodium persulfate using TRIUM’s ChemOx® process. The treatment successfully removed all residual NAPL, fully remediated the plume area, and exceeded performance expectations within a short timeframe.

Gas Station Remediation Southern Alberta: ISCO & SVE Treatment

A closure-based in-situ chemical oxidation (ISCO) remediation was conducted at a former gas station in Southern Alberta to address BTEX, F1, F2, and PAH contamination in 6,630 m³ of impacted soil, bedrock, and groundwater, including off-site impacts beneath residential properties. Due to infrastructure constraints and vapour risks, a Remediation Train® approach was implemented, starting with a soil vapour extraction (SVE) and air sparge system, followed by a ISCO program with a 3-meter injection radius. Nested injection wells targeted various depth intervals, with careful scheduling around residential activity. Over 45 days, 1.6 million liters of 10% EHP (enhanced hydrogen peroxide) was injected using TRIUM’s ChemOx® process, achieving daily blend volumes of >35,000 L. The treatment successfully met regulatory groundwater quality guidelines, managed vapour risks, and was recognized as an industry-leading process by consultants, with no negative impact on the community.

Case Study: