222Rn flux (Bq s(-1)) was measured from the ends of twenty sections of produced water injection tubing (pipe) containing barite scale contaminated with naturally occurring radioactive material. Exposure measurements near the pipes were as high as 77.4 nC kg(-1)h(-1) (300 microR h(-1)). Flux measurements were accomplished by first purging the pipes with dry nitrogen and then collecting the outflow (nitrogen and radon) on charcoal columns affixed to the end of the pipe for 66 hours. As determined in this manner, 222Rn flux from the ends of the pipe ranged from 0.017 to 0.10 Bq s(-1) (0.46 to 2.7 pCi s(-1)). Following the radon flux measurements, pipe scale was removed and a representative sample was taken for 226Ra and 228Ra concentration measurements and determination of 222Rn emanation fractions (the fraction of the total radon contained in a material that is released from the material and free to migrate). The samples were also analyzed for gross mineral content. Emanation fraction measurements for 222Rn ranged from 0.020 to 0.063, while 226Ra concentrations ranged from 15.7 to 102 Bq g(-1) (424 to 2,760 pCi g(-1)). Barite was the predominate mineral in 17 of the 20 scale samples collected. Much of the previous work dealing with radon emanation fraction measurements has involved uranium mill tailings. Compared to mill tailings and natural soils which have emanation fractions that typically range from 0.1 to 0.3, the emanation fractions measured for these NORM scales are substantially lower.
NBS SRM 1635 and NBS SRM 1632a were analyzed for trace and minor element contents by instrumental neutron activation analysis. The results of these analyses show excellent agreement with NBS certified values and/or literature values.
to develop and test a near real-time beryllium monitor for airborne and surface measurements. Recent public awareness of the health risks associated with exposure to beryllium has underscored the need for better, faster beryllium monitoring capabilities within the DOE. A near real-time beryllium monitor will offer significant improvements over the baseline monitoring technology currently in use. Whereas the baseline technology relies upon collecting an air sample on a filter and the subsequent analysis of the filter by an analytical laboratory, this effort developed a monitor that offers near realtime measurement results while work is in progress. Since the baseline typically only offers after-the-fact documentation of exposure levels, the near real-time capability provides a significant increase in worker protection.The beryllium monitor developed utilizes laser induced breakdown spectroscopy, or LIBS as the fundamental measurement technology. LIBS has been used in a variety of laboratory and field based instrumentation to provide real-time, and near-real-time elemental analysis capabilities. LIBS is an analytical technique where a pulsed high energy laser beam is focused to a point on the sample to be interrogated. The high energy density produces a small high temperature plasma plume, sometimes called a spark. The conditions wit hin this plasma plume result in the constituent atoms becoming excited and emitting their characteristic optical emissions. The emission light is collected and routed to an optical spectrometer for quantitative spectral analysis. Each element has optical emissions, or lines, of a specific wavelength that can be used to uniquely identify that element. In this application, the intensity of the beryllium emission is used to provide a quantitative measure of the abundance of the element in the sample.The monitor can be operated in one of two modes, as a continuous air monitor (CAM), or as a wipe monitor. In its CAM mode, the monitor collects an air sample for a user programmable sampling time on a conventional mixed cellulose ester (MCE) filter. The monitor can also be used in a wipe analysis mode, where the user can load up to 60Science & Engineering Associates, Inc. Final ReportContract DE-AC26-00NT40768Page ii previously collected wipe samples, typically obtained on 47 mm filter media, into disposable filter cassettes.Under this effort, a beryllium monitor was designed, fabricated and t ested. During laboratory testing, the monitor's measurement performance met the stated measurement objectives at the outset of the project. A typical minimum detectable beryllium mass for the monitor is below the 0.2 mg/m^3 goal of the project. Field-testing of the monitor show it to exhibit extremely good sensitivity to very low levels of beryllium. On a per spark basis, the monitor has been shown to be capable of detecting a few tens of picograms of beryllium. At the culmination of the project, the beryllium CAM unit was delivered to the U.S. DOE-Rocky Flats Environmental Management Site where it is u...
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