The discussion over radiological contamination in Pike County is an ongoing story with a third-party assessment of the situation still pending.
The latest development in the narrative seems to boil down to whose results from Memorial Day sampling at Zahns’ Corner Middle School does one believe — results from the health district and scientists conducting research at Northern Arizona University (NAU), the Ohio Department of Health (ODH), or the U.S. Department of Energy (DOE).
The Scioto Valley Local School District Board of Education decided to close Zahn’s Corner Middle School as of Monday, May 13 due to the detection of enriched uranium inside the school building during a recent study by scientists which was released by Northern Arizona University on April 27 and detection of neptunium-237 in a U.S. Department of Energy air monitor adjacent to the school.
It was also announced recently that americium-241 was detected at the school air monitor in 2018. The neptunium detection was from 2017 but was only made public in recent months.
According to the Pike County General Health District, americium-241 is a radioactive isotope with health effects similar to neptunium. Neptunium is a transuranic element and a known carcinogen (cancer-causing substance), according to the health district.
The Pike County General Health District and others have expressed belief that neptunium reached the air monitor at the school as a likely result of the construction of the waste disposal facility at the site of the nearby Portsmouth Gaseous Diffusion Plant in Piketon.
Samples taken during the Memorial Day weekend were taken to the Ohio Department of Health; the county (which sent their samples to scientists who tested the results at Northern Arizona University); and DOE, for separate analysis.
In a July 25 update, the Pike County General Health District stated that they, along with members of the Scioto Valley Local School District and other stakeholders, met on July 24 with DOE and the Ohio Department of Health to review and discuss the data collected by DOE during the memorial day sampling event at Zahn’s Corner Middle School.
“As we reported in our 5/29/19 community update, we were very concerned with the sampling exercise and the lack of communication before, during, and after the event,” the health district stated. “This lack of communication led to the use of different testing methods and techniques resulting in conflicting results between DOE, ODH, and the health district.”
According to the health district, their samples were analyzed by Northern Arizona University, and their results confirmed the NAU report from April 27, “confirming the original assumption that there is enriched uranium in dust found inside the school and the source was the DOE site. NAU did not analyze for any other radiological contaminants.”
The DOE Portsmouth/Paducah Project Office’s Sampling Analysis Report stated that only naturally occurring radionuclides were found in any of their samples and that none of their samples indicated any excess radiological risk above background to the public.
In the method and analysis summary for Group 1 of DOE’s tested samples, DOE’s report states, “Results were received from 39 samples. For gross alpha activity, 38 samples were below minimum detectable activity. The alpha activity was above the minimum detectable activity (MDA) for one sample, but within twice the uncertainty of the MDA value for this sample. That is to say, the measurement uncertainty of the result overlapped the minimum detectable activity. This means that the measured value is not statistically different than the MDA. This result was roughly 1/10,000 of the calculated deposited activity that would result in a member of the public receiving 100 mrem per year, based on the isotopic ratio observed by Moody, et. al. (1995) for samples from the Portsmouth site. For the gross beta activity, 35 samples were below minimum detectable activity. Four samples were above the minimum detectable activity for beta.
“All four samples with measurements above the detection limits of gross alpha/beta counting were sent for additional investigation using destructive analysis followed by alpha spectroscopy. Alpha spectroscopy is a laboratory technique used to specifically identify an alpha-emitting radionuclide and quantify the amount that is present. Alpha spectroscopy is generally used following a laborious chemical separation process that is needed to remove material that would interfere with obtaining a clean alpha spectrum.
“Follow up analysis via digestion, radiochemical separation, and alpha spectroscopy on samples taken at VSP-19, VSP-25, VSP-30, and VSP-40 showed that no artificial radionuclides (Np-237, Pu-238, Pu-239, or Am-241) were detected above the method detection limits. For the naturally-occurring isotopes of uranium and thorium, the measured values on the smears were consistent with the natural activity of uranium and thorium in the smear media itself. The ratio of U-234 to U-238 was consistent with what would be expected in natural uranium. In all smear samples, U-235 was not measured above the method detection limit. The follow-up radiochemical analysis confirmed that while radioactivity was present on the smears, it was due to naturally occurring radionuclides found in the dust and dirt and on the filter media itself.”
According to a report from ODH on July 24, their results included the following:
“39 Surface Wipes — All samples for gross beta were at or near minimum detectable activity and no samples had gross alpha detections. None required further analysis by alpha spectroscopy.
“Seven Air Samples — For both the low & high-vol air samples collected, each of the 10 radionuclides were below the laboratory’s minimum detectable activity (MDA).
“Eight ICP-MS Wipes — Highest wipe measurement was less than one dpm (disintegration per minute) which is extremely low.”
ODH stated, “Based upon the laboratory data results for the samples collected at the school, ODH does not see evidence of public health risks due to radiation.”
Brandon Wooldridge, of the Scioto Valley Local School District, expressed his concerns about the different results from the Memorial Day sampling.
“As we have reported before, we were very concerned with the sampling exercise because DOE rushed the process and failed to obtain agreement among the parties as to purpose (what they were attempting to accomplish with the sampling) and the methods used to analyze the samples,” Wooldridge stated in a July 25 Facebook post.
“As a reminder, DOE intended to only take surface samples on areas that are routinely cleaned such as desks and tabletops which led us to refuse their admittance to the school. We were successful in forcing DOE to expand the sampling to include areas more representative of the actual condition inside the school. We also obtained duplicate samples, as did the ODH. Unfortunately, DOE failed to gain agreement on the methods used to analyze the samples.”
Wooldridge said that DOE, ODH, and local samples were analyzed using differing methods and techniques.
“And just as predictable, the results were not similar,” he said. “So here we sit, inconclusive data results from May and positive results for contamination from the Northern Arizona University sampling and analysis revealed in April. That is exactly why we took the proactive step to close the Zahn’s Corner School for at least the next year until we can have confidence that we know how much contamination is present and — more importantly — that we can ensure our children and staff are provided a safe and healthy environment to teach and learn.”
A report on the Memorial Day sampling event, dated June 21, from Michael E. Ketterer, Ph.D., professor emeritus, chemistry and biochemistry of Northern Arizona University, and Scott C. Szechenyi, M.S., independent consultant, was sent to Matt Brewster, health commissioner for the Pike County General Health District, confirming their previous finding of the presence of enriched uranium in the interior of Zahn’s Corner Middle School.
Ketterer and Szechenyi said that their study investigated isotope ratios of uranium (U) in dust from the middle school.
“In this work, two different groups of samples are reported: A) eight selected ‘swipes’ collected by the US Department of Energy contractors from Savannah River National Laboratory (SRNL) on May 25, 2019; and B) six selected samples were re-analyzed from previous dust swipes collected by Ms. Elizabeth D. Lamerson (fence-line neighbor of Piketon plant site),” they stated.
The principal question to be addressed in this report, they said, is “Can non-natural uranium be found in the Zahn’s Corner dusts, via evaluating the isotope ratio uranium-235/uranium-238?”
They said that their findings confirm the presence of enriched uranium in the dusts previously collected at the school. Their findings also stated that “the glass fiber media used by SNRL in the May 25, 2019 sampling event” at the school “were excessively contaminated with a high baseline level of naturally occurring uranium”, which they said “rendered the analysis of most of the SRNL swipe samples implausible.”
Ketterer and Szechenyi said that “despite the glass fiber media contamination scenario,” they conducted analysis of eight SNRL swipe samples, “including several of the more heavily loaded swipes, that had been collected from un-disturbed dust collection areas atop structural beams. These analyses revealed that sufficient enriched uranium was present to produce a significantly elevated uranium-235/uranium-238 ratio in three of the DOE samples.”
“Accordingly, we conclude that the SRNL sampling also revealed the presence of enriched uranium in Zahn’s Corner Middle School interior dusts, and such results confirm and reinforce our own previous studies,” they said.
“With a reasonable degree of scientific certainty, the enriched uranium is associated with the Portsmouth Gaseous Diffusion Facility (PORTS), as this plant is the only plausible proximal source of enriched uranium that could have become deposited in the school.
“Moreover, our previous April 27, 2019 report cited several additional lines of evidence linking offsite contamination to PORTS.”
DOE has agreed to fund an independent, third-party study to survey contamination issues, with the third party to be selected by local officials, including the Pike County General Health District, and this study is not the same as the sampling conducted over the Memorial Day weekend.
“Due to these conflicting results (from Memorial Day sampling), the importance of the independent, third-party assessment cannot be overstated,” the Pike County General Health District said. “Again, the purpose of the assessment is to determine the source, levels, extent — and most importantly, the risk to human health related to the offsite contamination.
“The independent assessment is moving forward with Solutient Technologies as proposed and once complete, the community will have a study and results that they can trust and we all can use to make the best decisions for the health and safety of our community. This assessment will be extremely comprehensive and include the testing of schools, private properties, and waters of the state.”
Wooldridge also emphasized the importance of the third-party assessment.
“The importance of the independent, third party sampling and analysis effort cannot be higher,” he stated. “We will support the efforts of the Pike County Health District to contract the independent assessment to understand the level and extent of contamination in our community. The schools and community deserve to know what is in our environment from the A-Plant. Once this next step is complete, we all can make decisions for our collective well-being.
“Rest assured, we will insist that DOE control their radioactive releases and that no one will occupy the Zahn’s Corner School until we are certain it is safe and our children and staff have no greater risk of exposure than any child in any other school in Ohio.”
The Northern Arizona University Report concerning the Memorial Day Sampling Event and the reanalysis of the original samples from the April 27 report can be found at https://www.dropbox.com/s/qxwjx5hurtjqctg/NAU%20Zahns%20PikeHealth%2021June2019.pdf?dl=0