Superfund Innovative Technology Evaluation (SITE)
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
You will need Adobe Reader to view some of the files on this page. See EPA's PDF page to learn more.
The Oxford Instruments Analytical, Ltd., (Oxford) X-Met 3000 TX (X-Met) XRF Services x-ray fluorescence (XRF) analyzer was demonstrated under the U.S. Environmental Protection Agency (EPA) Superfund Innovative Technology Evaluation (SITE) Program. The field portion of the demonstration was conducted in January 2005 at the Kennedy Athletic, Recreational and Social Park (KARS) at Kennedy Space Center on Merritt Island, Florida. The demonstration was designed to collect reliable performance and cost data for the X-Met analyzer and seven other commercially available XRF instruments for measuring trace elements in soil and sediment. The performance and cost data were evaluated to document the relative performance of each XRF instrument.
This innovative technology verification report describes the objectives and the results of that evaluation and serves to verify the performance and cost of the X-Met analyzer. Separate reports have been prepared for the other XRF instruments that were evaluated as part of the demonstration. The objectives of the evaluation included determining each XRF instrument’s accuracy, precision, sample throughput, and tendency for matrix effects. To fulfill these objectives, the field demonstration incorporated the analysis of 326 prepared samples of soil and sediment that contained 13 target elements.
The prepared samples included blends of environmental samples from nine different sample collection sites as well as spiked samples with certified element concentrations. Accuracy was assessed by comparing the XRF instrument’s results with data generated by a fixed laboratory (the reference laboratory). The reference laboratory performed element analysis using acid digestion and inductively coupled plasma – atomic emission spectrometry (ICP-AES), in accordance with EPA Method 3050B/6010B, and using cold vapor atomic absorption (CVAA) spectroscopy for mercury only, in accordance with EPA Method 7471A.
The X-Met portable XRF analyzer features a miniature, rugged x-ray tube excitation source for analyzing a wide variety of elements and sample materials, including alloys, environmental solids, and other analytical samples. Other features of the X-Met include: multiple x-ray beam filters, multiple calibration methods, and adjustable tube voltages and currents.
The analyzer weighs 4.5 pounds and can be powered in the field with a lithium-ion battery or 110-volt alternating current (AC). The X-Met XRF analyzer utilizes a Hewlett-Packard (HP) iPAQ personal data assistant (PDA) for data storage of up to 10,000 tests with spectra in its 64 megabyte memory. The iPAQ has a color, high resolution display with variable backlighting and can be fitted with Bluetooth® wireless printing and data downloading, an integrated bar-code reader, and wireless data and file transfer accessories. The X-Met analyzer can analyze elements from potassium to uranium in suites of 25 elements simultaneously.
This report describes the results of the evaluation of the X-Met analyzer based on the data obtained during the demonstration. The method detection limits, accuracy, and precision of the instrument for each of the 13 target analytes are presented and discussed. The cost of element analysis using the X-Met analyzer is compiled and compared to both fixed laboratory costs and average XRF instrument costs.