Back in October, I had some questions about the DEC's take on Naturally Occurring Radioactive Materials. Today, reading the Environmental Protection Agency's comments on the dSGEIS, I got a bit of a jolt.
I'd wondered:
Section 5.2.4.2 reports on tests of Marcellus samples from New York and Pennsylvania, concluding that:
"the results, which indicate levels of radioactivity that are essentially equal to background values, do not indicate an exposure concern for workers or the general public associated with Marcellus cuttings."
This leaves me wondering whether radiation conditions at the surface are higher than they are in most rock formations except the Marcellus.
The EPA seems to be wondering the same thing, but they have data to back it up. The Marcellus has more NORM, at least in some places, than the DEC reported:
Page 5-34, Section 5.2.4.2 NORM in Marcellus Cuttings - This section states that the Marcellus Shale drill cuttings data reported from Marcellus wells in Pennsylvania are essentially equal to background values and do not indicate an exposure concern for workers or the general public associated with Marcellus cuttings. While this may be true for some of the data sets, other data should also be taken into consideration and it should be made clear that the data referred to in the revised dSGEIS do not represent the entire radiological conditions of the Marcellus Shale. That is, data reported in Table 5.2b coupled with Table 5.2a and Table 5.3 is evident of the heterogeneity of radioactivity in the Marcellus shale. Also, other data (see data submitted to EPA Region 3 from six drillers in Pennsylvania (http://www.epa.gov/region3/marcellus_shale/#wastewater)) collected from water and brine generated from well drilling activities in Pennsylvania seems to indicate elevated levels of radioactivity. As such, EPA recommends that the conclusion about the concentrations of naturally-occurring radioactive materials (NORM), specifically that these concentrations do not indicate an exposure of concern to works or the public, should be reconsidered or possibly removed because it is based on limited data that does not represent the radiological conditions in the entire Marcellus Shale. (Enclosure (220KB PDF), page 4, emphasis added.)
Their next paragraph is even more explicit:
Page 5-35-36, Table 5.2 2009 Marcellus Radiological Data - Table 5.2a (Marcellus Radiological data from Gamma Ray Spectroscopy Analyses) lists the isotopic concentrations of composited samples collected from two vertical wells drilled through the Marcellus shale, which are within background levels found in soil in New York and New Jersey. However, the exposure rate measurements listed in Table 5.2b (Marcellus Radiological data from Geiger Counter Screening) collected on Marcellus shale cores, outcrops and well sites from the west-central part of the state ranged from 3 to 13 times the ambient radiation exposure rate. Although, isotopic analyses to determine the radionuclide concentrations were not performed on the samples listed in Table 5.2b, the radionuclide concentrations, based on EPA Region 2's understanding of and experience with exposure rate data, are anticipated to be as high as 10 times those listed in Table 5.2a, suggesting the need for more vigilance in proper handling and disposal of such naturally-occurring materials from the Marcellus cuttings. (Enclosure (220KB PDF), page 4, emphasis added.)
Most of the comments are "one agency to another" kinds of things, suggesting, for instance, a lot more public mapping, but these really stood out to me. They also make me wonder if there's more to the radon concerns I raised in my own dSGEIS comments. If there's more radioactive material, there's likely more radon available to be carried with methane through cracks in the rock.
Posted by simon at January 12, 2012 6:25 PM in energy , geology