Study Finds Radiation Exposure Unlikely from Oil & Gas Development
A new study released from the Pennsylvania Department of Environmental Protection offered welcome news for residents and workers in the state. After years of research, the peer-reviewed study found that “there is little potential for harm to workers or the public from radiation exposure due to oil and gas development.”
The study looked at data for technologically enhanced naturally occurring radioactive material, or TENORM, in solids, liquids, natural gas, ambient air and on other surfaces. Sampling occurred at various locations across the state where exposure could potentially occur, including well sites, water treatment facilities, landfills, compressor stations and even on roads that used brine from hydraulic fracturing operations for dust control.
While DEP states more studies should be conducted in the future, the initial findings (page 18) were very positive.
1. “There is little potential for additional radon exposure to the public due to the use of natural gas extracted from geologic formations located in Pennsylvania.”
One of the things DEP studied was the actual natural gas that is used in homes and businesses across the state. Opponents of natural gas development have long used the claim that radon found in natural gas is at high enough levels to cause concern for homes that use natural gas for heat or appliances. As the following excerpt from a 2013 Desmogblog post shows, it was one of the talking points against the Spectra pipeline, which brings much needed natural gas from the Marcellus into New York City:
“Plans are underway to construct a pipeline that would carry Marcellus gas to the nation’s biggest city, New York City. But if that happens, some experts warn of a potential public health crisis. The problem centers around the way that radon breaks down. Radon has a half life of only 3.8 days, meaning that if the gas takes about a week to travel from the wellhead to the consumer, radons levels will have fallen of by 75 percent. But the Spectra pipeline would take Pennsylvania Marcellus gas to New York in less than a day, giving the radon very little time to decay.”
Fortunately for the residents of New York City and other end users of Marcellus gas, the study assumed there was no decay and found (emphasis added):
“Based on the Rn and natural gas data collected as part of this study and the conservative assumptions made, the incremental Rn increase in a home using natural gas appliances is estimated to be very small and would not be detectable by commercially available Rn testing devices. The radiation dose received by home residents is a small fraction of the allowable general public dose limit of 100 mrem/yr.” (pg. 150)
2. “There is little or limited potential for radiation exposure to workers and the public from the development, completion, production, transmission, processing, storage, and end use of natural gas. There are, however, potential radiological environmental impacts from O&G fluids if spilled. Radium should be added to the Pennsylvania spill protocol to ensure cleanups are adequately characterized. There are also site-specific circumstances and situations where the use of personal protective equipment by workers or other controls should be evaluated.”
One of the major questions that arises any time health is brought up in discussions about natural gas is whether workers would be the first individuals to show signs of exposure to radiation. They don’t, according to studies like the 25 year Health Surveillance Program conducted by the Australian Institute for Petroleum, which found,
“The chance of getting cancer is the same for men in this industry as for other Australians. This is so for all cancers combined and for most individual cancer types.” (Page 42)
DEP conducted the study for all areas of development from the well site to the end user, and found no causes for alarm with the levels of radiation workers are exposed to, as studies like the AIP research confirm.
In addressing concern for the public, the agency included the ambient air at the fence line near compressor stations in the study. The data showed more reassuring news:
“The average concentration at each fence line location was within the range of typical ambient background Rn concentrations in outdoor ambient air in the U.S. (Section 6.3)” (pg. 194)
This is great news for residents living near well sites or infrastructure.
3. “There is little potential for radiation exposure to workers and the public at facilities that treat O&G wastes. However, there are potential radiological environmental impacts that should be studied at all facilities in Pennsylvania that treat O&G wastes to determine if any areas require remediation. If elevated radiological impacts are found, the development of radiological discharge limitations and spill policies should be considered.”
DEP looked at three kinds of treatment facilities:
“1) Publicly Owned Treatment Works (POTWs) are the most common type of WWTPs. These facilities are designed to process sewage and wastewater from residences and businesses and may take industrial wastewater under specific circumstances. After the wastewater is processed and meets specified chemical criteria, the processed water may be discharged to streams under an NPDES permit.
2) Centralized Waste Treatment (CWT) facilities are designed to process commercial and industrial liquid wastes prior to discharge to receiving streams under an NPDES permit. Additionally, there are some industrial facilities that process wastewater prior to discharge to POTWs for final processing and discharge (pre-treatment).
3) Zero Liquid Discharge (ZLD) facilities are the most modern and utilize distillation and chemical technologies to remove solids from the wastewater. The processed wastewater is returned for reuse at natural gas well sites for hydraulic fracturing of new wells. All centralized ZLD facilities that recycle water to be used for hydraulic fracturing must be permitted by DEP.” (pg. 24)
Included in the survey were three POTW facilities that have never received oil and gas waste for background figures. And in all cases, data showed no cause of alarm for workers at the facilities or the public residing nearby.
4. “There is little potential for radiation exposure to workers and the public from landfills receiving waste from the O&G industry. However, filter cake from facilities treating O&G wastes are a potential radiological environmental impact if spilled, and there is also a potential long-term disposal issue. TENORM disposal protocols should be reviewed to ensure the safety of long-term disposal of waste containing TENORM.”
All materials entering a landfill must be tested for TENORM, including those materials from other industries. DEP tested samples at 51 landfills in Pennsylvania, and conducted further sampling of nine of those facilities based on the large quantities of waste from oil and gas operations the landfills accepted. The agency also took soil samples from any landfills that release effluent (treated) water into the environment.
Data showed (emphasis added):
“22.214.171.124 Landfill Worker Potential Internal Alpha/Beta Radioactivity Exposure
The total and removable alpha/beta survey results are presented in Sections 126.96.36.199 and 188.8.131.52. None of the 195 alpha measurements and 17 of the 195 beta measurements of total surface radioactivity exceeded the RG 1.86 criteria. None of the 205 removable alpha or beta surface radioactivity measurements exceeded the RG 1.86 criteria. The average values for total and removable alpha and beta surface radioactivity are below the RG 1.86 criteria, indicating that there is little potential for internal alpha and beta exposure to landfill workers.
184.108.40.206 Landfill Worker Internal Radon Exposure
The results of the landfill ambient air Rn samples are presented in Section 5.2.4. The Rn in ambient air at the fence line of the landfills ranged from 0.2 to 0.9 pCi/L consistent with U.S. background levels of 0.2 – 0.7 pCi/L in outdoor ambient air. Consequently, the potential for internal Rn exposure is low.” (pg. 135)
5. “While limited potential was found for radiation exposure to recreationists using roads treated with brine from conventional natural gas wells, further study of radiological environmental impacts from the use of brine from the O&G industry for dust suppression and road stabilization should be conducted.”
In some areas, brine is used on roads to decrease dust and stabilize the road. This is not a main use for brine or even a common practice. Nonetheless, the data showed a low risk for radiation exposure in these instances.
Interestingly, the data also showed residents who live near places where brine is used in this manner actually have less exposure risks than recreationalists, as explained in the following excerpt:
“The recreationist is an appropriate exposure scenario based on the remote location of the roads. A recreationist, such as a jogger or hunter, usually spends less time on the impacted area, e.g., two hours a day, three days a week, than a resident. However, a recreationist may have a higher inhalation rate than a resident. Recreational land use addresses exposure to people who spend a limited amount of time at or near a site while playing, fishing, hunting, hiking, or engaging in other outdoor activities.” (pg. 158)
While DEP did say further testing should be conducted, initial data still show a low risk of exposure.
All in all, the study is good news for both residents and workers in Pennsylvania. Certainly, this study won’t be the last word on the subject, but it can allay local fears – especially as neighboring states take radical steps against development based on baseless allegations of harm.