Story

Project

Ex Situ treatment of sediment containing PAHs

Hamilton Harbor

Hamilton, Ontario

 

Summary

The effectiveness of DARAMEND® bioremediation was demonstrated on 150 tons of sediment dredged from PAH impacted regions of Hamilton Harbor. The harbor is adjacent to a heavily industrialized area, and the sediments were impacted with a variety of contaminants including residue from coal coking operations for the steel manufacturing industry. PAH concentrations exceed 1,400 mg/kg in regions of the harbor. Following 312 days of DARAMEND® treatment, mean total PAH concentrations were reduced from 1,139 mg/kg to 110 mg/kg.

 

The Challenge

Remedial goals for the PAHs were established by the Canadian Council of Ministers of the Environment (CCME) in 1991 (Table 1). 

 

The Solution

At this site, the technology involved a solid phase aerobic approach utilizing indigenous microorganisms in an engineered bioremediation cell (EBC). The technology was site specific and involved the addition of nutrients and proprietary organic amendments (DARAMEND®) to optimize the rate of microbial activity in the sediment. Prior to initiation of treatment, the dredged sediment was allowed to passively dewater within the bioremediation cell. During treatment, close control of sediment moisture content was maintained through irrigation and tillage. Tilling was accomplished using specialized rotary tillage equipment with an effective tilling depth of 2 ft. 

The Result

Total PAH concentrations were reduced from 1,139 mg/kg to 110 mg/kg after 312 days of treatment, which comprises a reduction level of 90%.

The Cost

The cost to treat the soil was approximately $75 per ton. 

 

The Timeline

With the exception of benzo(a)pyrene, all regulated PAH isomers were below the guidelines after 245 days of treatment. Benzo(a)pyrene was reduced below its target after 312 days.

 

 

Table 1.  Influence of DARAMEND® bioremediation on the concentration of PAHs during field-scale treatment of sediment dredged from Hamilton Harbor, Hamilton, Ontario.

 

 

For more information, please contact us at:

ADVENTUS AMERICAS INC. 

2871 W. Forest Road, Suite 2 

Freeport, IL  61032 

Ph. 815.235.3503 

Fx. 815.235.3506 

 

ADVENTUS REMEDIATION

1345 Fewster Drive

Mississauga, Ontario, Canada

Ph. 905.273.5374

Fx. 905.273.4367