Question from Blog Reader:
(did not leave email address)
Thank you for your questions:
Here are some of the references you requested.
New York Permit conditions require flow-back fluids to be contained in sealed containers. Example of sealed container- http://www.epmag.com/Magazine/2010/8/Images/August_Drilling&CompletionsFluids_SWSI_1.jpg
I am not sure what you refer to steamy white wafts of clouds leaving the site. However, visual or odor detection does not necessarily mean toxic. The concentration of whatever is contained in the “White wafts” has to be high enough when it gets to the nearest person, it also has to be at the right exposure length and also has to have some related toxicity value and then it has to be able to exert an effect.
This article by Captain Esswein discusses and addresses some of the concerns raised and offers solutions. Silicosis is a potential hazard but in a literature review of studies on Oil and Gas workers there have been no cases that have been found as a result of this type exposure. However, it is still important to protect workers and devise safer methods. http://blogs.cdc.gov/niosh-science-blog/2012/05/silica-fracking/
Are determined site specific- permit based. The sGEIS only offers recommendations. The permit writer reviews the permit and site and determines what a safe setback is. Obviously it has to be far enough to prevent air emission exposure at levels of concern. City of Fort Worth did an air study, Colorado Department of Public Health and ASTDR did studies and found that air emission dissipated the further you went from the well pad - hence the importance of setbacks.
Link to Oil and Gas Workers study: http://www.aip.com.au/health/ohs.htm
Dry gas in NorthCentral PA: http://www.dep.state.pa.us/dep/deputate/airwaste/aq/aqm/docs/Marcellus_NC_05-06-11.pdf (page iii)