What I want to do
Develop a sampling procedure for oil sheen on water to support groups such the North Brooklyn Boat Club who do environmental advocacy on Newtown Creek. Increasingly frequent incidents of "unknown petroleum" are being reported, read the article here: http://www.dnainfo.com/new-york/20140820/greenpoint/businesses-near-newtown-creek-eyed-after-series-of-oil-spills-state-says
My attempt and results
Matt Pendergraft suggested to collect samples of sheen by placing an absorbent material on the surface of the sheen. The pad can be 'wrung out" to reduce the amount of liquid being carried around (b/c any liquid sample would be mostly water). Once collected, fold the pad for transit in aluminum foil, then put in ziploc bag.
To process it, extract the oil with another hydrocarbon, then siphon off the oil which presumably has risen to the top of the water.
In terms of what actual material to use, try using the absorbent pads used for gas spills in the bottom of boat because they don't soak up water--they soak up gas/oil. These are sold in home depot, auto supply stores, boat stores.
Questions and next steps
I am planning to purchase a variety of motor oils and gasolines to test sample preparation and analysis with.
- will gasoline sheen evaporate away because it’s so volatile?
Why I'm interested
Oil and gas sheen on water is the most common question i get in the New York / New Jersey area (with particulate air pollution a close second). So far, we've developed a clear sampling procedure for sampling a solid Gulf-style tar ball, which fortunately are rarely seen in this region at this time. I am hoping to advance our ability to work with more diffuse samples such as oil sheen on water that are common in this region.