Groundwater remediation action plan of polluted aquifer by heavy fuel oil, Northern Jordan

ABSTRACT This study investigates the sources and pathways of groundwater contamination by heavy fuel oil (HFO) at the Al Hussein Thermal Power Station (HTPS) in northern Jordan using hydrogeological and geophysical methods. Initial surveys identified Wells #8 and #9 as primary contamination points, revealing that the contamination originated from a leaking oily water drain beneath the boilers at HTPS. The contamination plume was confined to an area of approximately 0.5 km2 at a depth of around 50 m, confirmed by additional boreholes near the plant boundaries. To remediate the polluted groundwater, the Central Electricity Generating Company (CEGCO) applied a pump-and-treat approach, extracting about 16,200 m3 of contaminated water over 3 months at a rate of 90 m3/h, twice daily. This process reduced total petroleum hydrocarbon levels from initial concentrations of over 10 mg/L to below detectable limits (<0.5 mg/L). The pH-REdox-EQuilibrium modeling revealed that biodegradation of HFO led to increased levels of total dissolved solids from 1,400 mg/L to over 2,600 mg/L and elevated sulfate concentrations, impacting the aquifer's overall water quality. The remediation plan not only addressed immediate contamination but also focused on preventing further leaks and restoring groundwater quality in the long term.