Geochemical evaluation of biodegradation capacity in a petroleum contaminated aquifer
NING Zhuo1,2,3, GUO Cai-juan1, CAI Ping-ping1,4, ZHANG Ming1, CHEN Zong-yu1, HE Ze1,3
1. Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, Shijiazhuang 050061, China;
2. Chinese Academy of Geological Sciences, China University of Geosciences in Beijing, Beijing 100083, China;
3. Key Laboratory of Groundwater Remediation of Hebei Province, Shijiazhuang 050061, China;
4. School of Resources and Enviromental Engineering, HeFei University of Technology, Hefei 230009, China
It is essential to determine the biodegradation capacity when monitoring or enhancing natural attenuation of petroleum in contaminated aquifers. Here, the concentrations of typical electron donorcontaminants (benzene, toluene, ethylbenzene, and xylene, and chemical oxygen demand) and electron acceptors and byproducts (dissolved oxygen, NO3-, Mn2+, Fe2+, SO42- and HCO3-) in a petroleum-contaminated aquifer were determined. The background electron acceptor/byproduct concentrations were determined from the electron donor concentrations, and the acceptor/byproduct distributions were characterized. The biodegradation capacity at each well was estimated using a general geochemical evaluation method. The cumulative probability curve method was used withthe general method to evaluate the biodegradation capacities in the aquifer. The biodegradation rates were determined from the biodegradation capacities and groundwater renewal rates, and different biodegradation zones were identified from the biodegradation rates. The biodegradation capacities of the wells were 36.49~70.05mg/L, and the biodegradation capacity cumulative probability curve for each well fitted the exponential equation F(x)=0.008e0.07x. The whole-aquifer biodegradation capacity (determined using the probabilities for the different aquifer parts) was 57.83mg/L and the whole-aquifer biodegradation rate (calculated defining the groundwater renewal rate as the groundwater runoff rate, 132m3/d) was 2790kg/a. The downstream source zone was found to have a strong biodegradation capacity. It was concluded that petroleumcontaminants were mainly degraded by the electron acceptors SO42- and NO3- reduction. Enhancing SO42- and NO3- reduction may be a promising way of managing and remediating the study site.
Schreiber M E, Carey G R, Feinstein D T, et al. Mechanisms of electron acceptor utilization:implications for simulating anaerobic biodegradation[J]. Journal of Contaminant Hydrology, 2004,73(1):99-127.
[7]
Newell C, Mcleod R K, Gonzales J R. BIOSCREEN:Natural attenuation decision support system. User's Manual Version 1.3[M]. 1996.
[8]
Newell C J, Aziz C E. Long-term sustainability of reductive dechlorination reactions at chlorinatedsolvents sites[J]. Biodegradation, 2004,15(6):387-394.
[9]
Mackay D, Paradis C, Buscheck T, et al. Methods to estimate source zone depletion of fuel releases by groundwater flow[J]. Groundwater Monitoring & Remediation, 2018,38(1):26-41.
[10]
Suarez M P, Rifai H S. Evaluation of BTEX remediation by natural attenuation at a coastal facility[J]. Groundwater Monitoring & Remediation, 2002,22(1):62-77.
Wiedemeier T H, Rifai H S, Newell C J, et al. Natural attenuation of fuels and chlorinated solvents in the subsurface[M]. New York, 1999.
[13]
Lu G, Clement T P, Zheng C, et al. Natural Attenuation of BTEX Compounds:Model Development and Field-Scale Application[J]. Groundwater, 1999,37(5):707-717.
[14]
Uçanku? T, nlü K. The effect of aquifer heterogeneity on natural attenuation rate of BTEX[J]. Environmental Geology, 2008,54(4):759-776.
[15]
何泽,宁卓,张敏,等.基于统计的基因定量技术圈定隐蔽油气藏有利区[J]. 地球科学, 1-10.
[16]
Ahrens L H. The lognormal distribution of the elements (A fundamental law of geochemistry and its subsidiary)[J]. Geochimica Et Cosmochimica Acta, 1954,5(2):49-73.
[17]
Meckenstock R U, Elsner M, Griebler C, et al. Biodegradation:updating the concepts of control for nicrobial cleanup in contaminated aquifers[J]. Environmental Science & Technology, 2015,49(12):7073-7081.
Ning Z, Zhang M, He Z, et al. Spatial pattern of bacterial community diversity formed in different groundwater field corresponding to electron donors and acceptors distributions at a petroleum-contaminated site[J]. Water, 2018,10(7):842.