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A portable, battery-powered, multichannel analyzer (MCA) for use with Ge spectrometers has been developed for in-field use for the assay of xand 7-ray emitting radionuclides. The spectrometer is capable of operating to rates greater than 150,000 counts per second. The analyzer is a Canberra InSpector MCA, that is equipped with the INEEL ultra-stable dual-energy pulser, and pulse injection with subsequent removal (PISR) circuitry. PCGAP, a set of MCA control and spectral analysis programs, was developed for use on a PC with a Windows NT Operating System. It includes an interactive peak analysis program as well as automatic spectral analysis programs for the X-and 7-ray regions, and a number of utility programs. The pulser peaks are calibrated with radioactive sources in terms of energy (i.e., their energy equivalents are measured) using the PCGAP spectral analysis package so that energy shifts, including those due to changes in temperature or count rate, do not cause a loss of energy calibration. The number of injected low-and high-energy-equivalent pulses is known so the stored pulser pulses can be used for a dead-time and random summing correction. The pulser peaks are also used to monitor any deterioration in spectral quality caused by noise, ground loops, etc. The results of performance tests to demonstrate the capabilities of this pulser-equipped InSpector are reported.

The cleanup of high-level defense nuclear waste at the Hanford Site presents many challenges. These include removing and disposing of components from buried active waste tanks to allow new equipment insertion or hazards mitigation. This paper discusses a unique automated system that provides for retrieval, high-pressure washing, inventory measurement, and containment for disposal. Key to the inventory measurement is a three-detector high-purity germanium high-performance gamma-spectroscopy system capable of recovering data at up to 90-percent saturation (200,000 counts/s). Data recovery is based on a unique embedded electronic pulser and special software to report the inventory. Each detector has different shielding specified through simulation using the Monte Carlo computer code for N-particle transport modeling. This shielding provides performance over a dynamic range of eight orders of magnitude. This paper covers system description, calibration issues, and operation.

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A technique has been developed to rapidly measure the presenw of plutonium in soils, lilters, smears, and glass waste forms by measuring the uranium L-shell x-ray emissions associated with the decay of plutonium. In addition, the technique can simultaneously acquire spectra of samples and automatically analyze them for the amount of americium, and gamma-ray emitting activation and fission products present. The samples are counted with a large area, thin-window, n type Ge sp~ctrometer which is equally efficient for the detection of low ener~x-raw (> 10 kev)> as WCIIas high-energy gamma rays (> 1 MeV). A 8192-channel analyzer is used to acquire the entire photon spectrum at one time. A dual-cner~, time-tagged pulser, that is injected into the test input of the preamplifier to monitor the energy scale, detector resolution, and pulse pile-up will be installed in FY-92. The L x-ray portion of each spectrum is analyzed by a linear Ieast-squares spectral fitting tcchniquc originally developed for the analysis of spectra from NaI('fl) detectors. The gamma-my portion of each spectrum is analyzed by a standard Ge gamma-ray analysis package. Detection Iimils (also referred to as lower limits of de(cction) for plutonium in contaminated soils that have been achieved by this technique are reported..,.