Q: What are the advantages of “Dig & Haul”?
A: Over the years, developers have turned to soil excavation and removal (dig & haul) as the “go-to” remedy in addressing contaminated soils at brownfield sites because of its speed, reliability and certainty.

Once the soil is exposed, one can easily determine whether there is additional contamination that needs to be addressed. Contaminated soils can be rapidly removed, thus increasing the efficiency of the clean-up.

Q: What are the disadvantages of “Dig & Haul”?
A: Cost is the main disadvantage to the “Dig & Haul remedy. There are many issues associated with the soil excavation process that would increase the cost for developers, particularly in cases where the soils are considered hazardous waste.

In cases where soil is considered hazardous, it must be taken to disposal facilities designed to accept these wastes. Hazardous disposal facilities have higher disposal fees and are often are located at greater distances than non-hazardous disposal facilities, adding to transportation costs.

Lastly, in all instances of hazardous waste removal, there may be some general negative public perception associated with the process.

Q: Please compare in-situ vs. ex-situ strategy
A: An ex-situ strategy is when the site is treated through the action of exposing and removing the contaminated materials from their original location (i.e. the “dig & haul” remedy is considered to be an ex-situ strategy).

An in-situ strategy is when the contaminated materials can be treated on site without removal or exposure. An in-situ strategy is most advantageous because it’s favorable to public perception and its potential for re-use of the soil and cost. 

Q: What are the in-situ technologies that are most promising for brownfield projects?
A: Soil vapor extraction and soil venting have been available and successful in remediation of contaminated sites. These technologies have been used often in the brownfield industry. However, like all technologies, these are not fail-safe solutions. In some cases, these remedies may fail due to high contaminant concentrations, shallow water tables or poor soil conditions.