C.J. Barton, Sr. at ORNL: Radon in the Home

It took me along time before I fully realized what a good scientist my father was. I was aware of his career problems. By the time I went i went to work at ORNL in 1970, Oak Ridge gossip had it that my father could no longer cut it in the Lab. This was nonsense, but I did not know it at the time. Many of my fathers problems as a scientist, stemmed from his social, and cultural heritage which was different from that of the ORNL leadership, and from his speech problem. Scientists like George Parker, with whom he shared a common cultural background, and a passion for lab research, held my father in high regard. My father was about to prove that he still was a very capable scientist.

The crises that gripped ORNL in the late 1960's and early 1970's is not fully appreciated now. There were three different issues that were effecting ORNL funding: the war in Vietnam, the space program, which was sucking up research dollars for Werner von Braun's trip to the moon, and the efforst of Congressman Chet Holifield, and AEC big wig Milton Shaw to destroy ORNL, in order to silence ORNL researchers on nuclear safety.

In 1969 the crumbling Reactor Chemistry Division loaned my father to the well funded Health Physics Division. My father was never to be involved in reactor chemistry again, and a couple of years later he was administratively transfered to the new Environmental Studies Devision. He fit right in with his new associates. The Gasbuggy project grew out of the illusion that nuclear explosions could be used for peaceful purposes. When my father went to work on the project, it had already seen better days, but when he took it over, with the assumption that a retiring scientist could close the door behind him as he left ORNL, my father had other ideas. This account demonstrates how he latched on to the problem of environmental radon, and the enterprise he showed in conducting underfunded research. It is perhaps not fair to say that my father discovered the problem of radon in the home, but he clearly recognized the problem to a much greater extent than prior researchers, and he pushed for a more through investigation. He has never been fully credited with this effort.

RADON IN HOMES AND NATURAL GAS
Charles J. Barton, Sr.

Introduction

The great surge or attention to radon in homes that has resulted in numerous studies and articles has been or considerable interest to me because or my involvement in this subject at a time when interest was too low for me to obtain funding for extending the study that I had conducted as part or the Plowshare Project. The following is an account or my involvement in efforts to learn the possible effects or radon and its daughter products in homes, in particular the contribution or radon in natural gas to exposure in homes, and a somewhat larger study or radon in natural gas.

Radon In Natural Gas

In late 1969, the Reactor Chemistry Division at ORNL was experiencing hard times with sharp funding reduction and I was asked to go on loan to the Health Physics Division to work on the Plowshare Program with Don Jacobs. Don left in 1971 for a two-year stint at the IAEA in Vienna, leaving me in charge or the project. At that time the Plowshare program, with the Lawrence Livermore Laboratory having the principal responsibility was being cut back. Earlier, a variety or peaceful uses or nuclear explosives had been considered such as excavating harbors and enlarging the Panama Canal. The role or ORNL was limited to estimating doses that people might receive from these peaceful uses or nuclear explosives and. in particular, the use or these explosives to increase production or natural gas in rock formations underlying large areas or several western states such as Colorado and Utah. These formations are known to contain large quantities of natural gas but because of low permeability, the output of gas resulting from use of conventional drilling techniques is too low to be economical. It was expected that use of nuclear explosives would break the rock into small enough pieces to permit gas to flow at a reasonable rate. At the time I joined the project. The first experiment or this type, called Gasbuggy, had been performed, with the co-operation or the El Paso Natural Gas Company, near Farmington, New Mexico.

The Gasbuggy study showed that tritium in the gas produced by use or a nuclear explosive was the isotope of principal concern and that exposure to people in homes using the slightly radioactive natural gas was the exposure mode of principal concern. It was known that all natural gas contains a small amount or natural radioactivity in the form or radon. Don asked me to look into the question or how much radon .is in the natural gas used in homes and also the amount or radon entering homes from other sources. I conducted a fairly extensive review or the literature and round that there was a rather large number or measurements or the level or radon in gas at the wellhead in this country, made principally by Allan Tanner at the U.S. Geological Survey. I visited his Off1ce in Washington and obtained access to all his published data and some that had not previously been published. However, neither he nor anyone else had measured the radon concentration at points or use. Since radon has a 3.8-day half-life and several days may be required to move the gas from the wells to the point or use there can be a significant drop in radon concentration during transmission.

I also round a fair amount or data on radon concentration in homes, principally in the U.S. and Sweden. The New York Health and Safety Laboratory, operated by the AEC had made a few measurements in homes in their area. The only area where the measured level or radon was high enough to be considered a problem at that time was in Grand Junction, Colorado, where contractors had used tailings from a uranium mill as rill material under and around homes.

After considering making my own measurements of the radon concentration at various points or use around the country. I concluded that was impractical and I devised a strategy for getting the job done by others. By judicious enquiry, I learned the name and phone number or the highest placed official in the major gas pipeline companies supplying several metropolitan areas, whom I thought would understand my request for help. I went into this project with the notion that the big gas companies might consider radon in the gas they were selling to be something to be swept under the rug but, instead all the companies 1 contacted proved to be cooperative in meeting my request to supply samples or their gas once per month over a period or one year. This would help to determine whether there was any seasonal variation in the radon concentration in the gas. I also had to rind laboratories willing and able to measure radon. In some cases the gas pipeline company bore the cost or the sampling and analysis but none or the cost was borne by my project. Five big pipeline companies supplied gas samples representing gas supplied to four metropolitan areas once per month over a period or nearly a year and four laboratories measured the radon in the samples.

The next step was to calculate the radon daughter concentrations in homes that would result from using gas-containing radon in a vented home appliance. To do this I enlisted the help or Bob Moore who worked out a computer program to perform the necessary calculations. Paul Rohwer furnished the dose factors for converting the radon daughter concentrations into doses to the bronchial epithelium, which we assumed to be the critical tissue exposed to the radon daughters. We used the average or the radon measurements throughout the country TO calculate doses in homes under a variety or assumed conditions, thus satisfying the needs or the project. A literature survey supplied another bit or data needed in making these calculations: the average concentration of radon in outside air entering the home as ventilation air. All soil contains some uranium, which decays to produce a low level or radon in air.

Radon In Homes

I mentioned earlier that my literature survey completed in the early part or 1970 revealed a comparatively small amount or data on the concentration in homes and other structures in this country. Interest in this subject began to pick up in the early 70s. A team from the New York Health and Safety Laboratory came to Oak Ridge to make some measurements. According to my recollection they limited their choice or homes here-to those in the Woodland area on the theory that Chattanooga shale, which is known to contain a relatively high concentration or uranium, was used in making the concrete blocks in all the Woodland home walls. Their measurements indicated that the radon level in these homes was not high enough to get excited about. From here they went on to Florida where much or the sandy soil is known to contain a rather high concentration or uranium. There also, I think that their data did not cause a great deal or concern, possibly because most Florida homes are well ventilated at the time they were making their study.

Also, in the middle 70s, a team from ORNL equipped with a mobile laboratory started making surveys or abandoned former uranium mining sites in several western states. These were, in general, located in uninhabited areas so there was relatively little danger or human exposure to radon released from the uranium tailings. However, some instances or use or tailings in the vicinity or homes were uncovered by these studies. Before the ORNL team could rind time to prepare reports on their extensive surveys or mining and mill-tailing sites they were drafted for surveys or sites where uranium had been processed to supply uranium to the governments gaseous diffusion plants. These sites are located in general near inhabited areas and exposure of people in the vicinity or the sites to radon and its daughters was of greater concern than in the mining studies. These surveys and the resulting remedial work to clear the sites for other uses (the FUSRAP project) produced data on radon in homes and. probably stimulated other investigations in this area. Incidentally after my retirement from the lab in 1977, I was hired by ORNL through a contract with Science Applications to prepare reports on the surveys or the mining and mill tailing sites and to help with preparation or some or the early FUSRAP reports.

Conclusion

Where are we now in our knowledge or the concentration or radon in U.S. homes and their possible health effects on occupants or the homes? Two excellent reviews on this subject have come to my attention: Science. 29 April. 1988 and ANS News, June 1888. Results or a 1987 survey quoted in the latter source showed 34.070 measurements in the Northeast part or the country, 18.481 in the Northwest, 2.118 in the Mountain States. 1.582 in the Southeast, and 1,486 in the Midwest, The high number of measurements in the Northeast reflects the fact that hot spots n several states in this area. Forty four percent of the measurements in this area were above the 4 picocuries per liter guideline adopted by the EPA for occupied homes. Above this the EPA recommends that remedial action be taken but that he discretion or the homeowner. It is estimated that to 20,000 lung cancers a year may be attributed to radon ion in the United States. These figures, which are based on extrapolation or observed cancer deaths at much higher radon primarily among miners of uranium deposits, should be compared to the annual death rate from lung cancer in the U.S. of approximately 130.000. About 70% of these are attributed to cigarette smoking.

The radon level in homes having high levels lowered usually can be lowered at a comparatively low cost. The Science article indicates that the simplest way or dealing with the problem is to drill through the basement floor to the stone ballast below and continuously pump the air there the house. In this area (Oak Ridge and West Knoxville) a team from the Health and Safety Division, ORNL made measurements for radon and a number of other indoor pollutants in several homes including mine. They reported that the radon level in homes on the ridge, where our house is located, had a higher concentration (6.3 average in the basement. 4.4 in the living areas) as compared to those in the valley (3.3 in the basement, 1.7 in the living area) (Concentrations in picocuries per liter). However, the measured radon levels do not appear enough to warrant remedial action. I was pleased to learn that ORNL did get around to making these measurements in the April1982-February 1983 period, although I could not stir up interest in doing the job in the mid-70s. The technology for doing many or the measurements reported by the Health and Safety group did not exist at the time or my proposal.