Determination of ²²⁶Ra Contamination Depth Around Phosphogypsum Pit Using In-Situ Gamma Spectrometer

Area of Science:

• Environmental Science
• Nuclear Geophysics
• Radiological Assessment

Background:

• Phosphogypsum disposal pits can contain Radium-226 (²²⁶Ra) contamination.
• Accurate determination of ²²⁶Ra contamination depth (h_c) is crucial for environmental remediation.
• Traditional soil coring methods for depth determination are time-consuming and labor-intensive.

Purpose of the Study:

• To investigate the feasibility of using the multiple photopeak method (MPM) and peak to valley ratio method (PVRM) for determining ²²⁶Ra contamination depth.
• To compare the efficiency of MPM and PVRM with traditional soil coring techniques.

Main Methods:

• Gamma spectra were measured at eight locations around a phosphogypsum disposal pit using a portable NaI(Tl) gamma spectrometer.
• MPM involved calculating the ratio of 609 keV to 352 keV gamma line net counts.
• PVRM involved calculating the ratio of 609 keV gamma line net counts to valley counts.

Main Results:

• Both MPM and PVRM showed good linear correlations with ²²⁶Ra contamination depth (h_c) determined by traditional soil coring.
• The developed methods provide a reliable means for estimating ²²⁶Ra h_c.

Conclusions:

• MPM and PVRM are effective and feasible methods for determining Radium-226 contamination depth.
• These gamma spectrometry-based methods significantly reduce the time, cost, and effort compared to traditional soil coring.