Rapid on-site detection of underground petroleum pipeline leaks and risk assessment Using portable GC-MS and SPME

Pioneering Rapid Detection of Underground Petroleum Pipeline Leaks

Revolutionizing Environmental Monitoring with Cutting-Edge Technology!

I'm happy to share a novel and highly technical approach to detecting underground petroleum pipeline leaks, detailed in a recent study published in the Journal of Chromatography A. This research highlights the potential of portable gas chromatography-mass spectrometry (GC/MS) combined with solid-phase microextraction (SPME) for rapid and accurate on-site detection.

?? Site Specifics: The study was conducted at a car park area of a pier in West Australia, where a significant diesel leak had impacted the nearby shoreline and groundwater. The complex site conditions provided an excellent testbed for validating the robustness of this detection method.

Description of soil vapour probe install locations and the underground pipelines (Green: service lines, blue: return line). SVB#- Sampling points

Key Technical Highlights:

?? Innovative Detection Methodology: The study leverages the synergy between portable GC/MS and SPME for real-time assessment of soil vapor samples. This combination is optimized for detecting petroleum hydrocarbon volatile organic compounds (pH-VOCs), specifically benzene, toluene, ethylbenzene, and xylene (BTEX).

?? Optimization for Precision: Through meticulous benchtop studies, the researchers optimized SPME fiber materials and exposure times, preconditioning soil vapor samples at approximately 4°C using ethanol as a desorbing agent. This approach minimized moisture interference and enhanced the detection limits, with BTEX detection thresholds approaching 100 μg/m3 and measurement repeatability of about 5-15%.

?? Field Application and Environmental Impact: Applied in the field, this method successfully identified a diesel return pipeline leak caused by a gasket failure. Soil vapor samples collected from 1.5 meters below ground surface at multiple locations revealed a hotspot with BTEX concentrations as high as 30 mg/m3. Prompt detection facilitated immediate repairs, mitigating environmental damage and health hazards.

??? Advanced Sampling Techniques: The researchers employed retractable soil vapor bores (SVBs) to collect soil vapor samples. Using 1 L Tedlar bags within a controlled airbox environment, they ensured sample integrity by maintaining a vacuum. The samples were drawn through non-absorbent Teflon tubes connected to SVBs installed at strategic locations around the leak site. This meticulous sampling process, including the use of moisture filters and ethanol as a desorbing agent, optimized the analytical conditions for accurate field measurements.

?? Advanced Analytical Techniques: The use of a portable Torion-T9 GC/MS enabled rapid on-site analysis, eliminating the need for laboratory sample transport. The system's electron impact (EI) mode at 70 eV ionizing energy provided precise mass spectra, essential for accurate compound identification. The application of SPME with PDMS, PDMS-DVB, and PDMS-Car fibers demonstrated superior extraction efficiencies, particularly under controlled temperature and humidity conditions.

?? Results and Discussion: The research revealed that lowering the extraction temperature to 4°C significantly improved BTEX detection. Furthermore, integrating moisture filters and ethanol desorption enhanced the reliability of field data. The study's findings underscore the critical role of advanced portable analytical tools in environmental risk assessment and remediation.

Conclusion: This pioneering method using portable GC/MS and SPME represents a significant advancement in environmental monitoring, offering a robust, efficient, and cost-effective solution for detecting underground petroleum pipeline leaks. The ability to perform rapid, on-site analyses with high precision is transformative for both environmental protection and public health.

?? Source: Sciencedirect