Tuesday, April 9, 2013

Exploring Dirty Dirt

Part of my work involves contamination investigations. A different type of risk than the geology hazard assessment work I do. I have not posted much on the subject, but lots of geologists are employed in environmental contamination and cleanup work. Having an understanding of the underlying geology helps with understanding contamination fate and transport. It also helps in knowing the most efficient way to investigate a site. In the case below, I was fairly sure I might be able to pull off sampling to 10 feet or so, if needed, with hand tools - saves a bit of money for clients versus hiring out a backhoe or drill rig.  

Auger hole

Soil in auger from soil transition zone

I managed to auger two holes to the depth I needed to make a reasonable assessment of soil conditions. No big rocks or extremely compact soil blocked my efforts. I took a soil sample and performed a very complex field test. I placed some of the soil into a pan to see if any sheen would come off of the soil onto the water surface indicative of petroleum hydrocarbons. In this case I did get a sheen. I followed up by sending a sample to a chemistry lab for analysis.

Sheen test in action - panning for oil

1 comment:

Geoffrey Middaugh said...

Pretty good for hydrocarbons, but not so much for PPT's or PPB's of super bad stuff. Good field tool for monitoring for a LUST.