15 An Overview of Natural Water Contamination …
361
issues. Only those isotopes can be used as tracer which shows large mass difference
between common isotopes to rare isotopes of particular element. There are various
approaches to detect groundwater pollution like use of geochemical markers/tracers
and use of stable isotopes. Generally, isotopes of carbon and hydrogen are used for
evaluating natural attenuation of volatile compounds like BTEX, chlorinated solvents, or MTBE (Mulligan and Yong 2004). On the other side, larger molecules
like PAHs or PCBs, which shows minimal effects of biodegradation, correlation can
be develop by using individual isotopic fingerprint. Sources of contamination may
include natural seepage of supertankers crude oil, leaking pipelines, dioxins, hydrocarbon polychlorinated biphenyles (PCBs), pesticides and many different types of
chemical from various sources. In some cases, traditional techniques for characterization of spill/contaminants sources such as gas chromatography (GC) and gas
chromatography—mass spectrometry (GCMS), may be obscure and inconclusive.
The reason behind such ambiguous GCMS or GC data set is change in the distribution
of components of original samples and spilled material due to weathering processes
like biodegradation, evaporation and photooxidation. Depending on the environmental conditions, after the spill, evaporation may lead to remove volatile compounds,
and water washing may lead to remove soluble components like hydrocarbons in
aquatic environment. Simultaneously, biodegradation may change the distribution of
compounds. Therefore, correlation of sources and spilled material requires selective
parameters that should be insensitive to environmental conditions (Lu et al. 2015).
Chlorine isotopes are widely used for the study of chlorinated contaminants like
PCBs, dichloro-diphenyl-tricholoroetane (DDT), and dioxins in the environment.
Hunkeler et al. (2005), discussed plume study data of chlorinated hydrocarbon. The
dehydrochlorination of 1,1,2,2,PCE to TCE was found to be predominant pathway.
Some studies showed enrichments of
13 C in VCE and cis-DCE are indication of
dechlorination and compound-specific isotopes analyses (CSIA) data permitted to
determine the rate of bioaugmentation. Hence, we conclude that stable isotopes are
useful to monitor natural attenuation.
15.5 Sustainable Risk Assessment and Groundwater
Impact/Status
Water security is a considerable concern, especially in countries facing remarkable
population growth and vulnerable climate. There can be many reasons to consider
sustainable water management as an important environmental assessment tool like
less groundwater recharge, deterioration of groundwater quality due to seawater
intrusion, high rainwater runoff, and increased wastewater generation by growing
population. Water recycling through aquifers is an important study for sustainable
water management. Managed aquifer recharge (MAR), to replenish groundwater in
urban environment plays a major role worldwide. It depends on natural treatment
processes which take place within the aquifer like infiltration, sorption, degradation,
361
issues. Only those isotopes can be used as tracer which shows large mass difference
between common isotopes to rare isotopes of particular element. There are various
approaches to detect groundwater pollution like use of geochemical markers/tracers
and use of stable isotopes. Generally, isotopes of carbon and hydrogen are used for
evaluating natural attenuation of volatile compounds like BTEX, chlorinated solvents, or MTBE (Mulligan and Yong 2004). On the other side, larger molecules
like PAHs or PCBs, which shows minimal effects of biodegradation, correlation can
be develop by using individual isotopic fingerprint. Sources of contamination may
include natural seepage of supertankers crude oil, leaking pipelines, dioxins, hydrocarbon polychlorinated biphenyles (PCBs), pesticides and many different types of
chemical from various sources. In some cases, traditional techniques for characterization of spill/contaminants sources such as gas chromatography (GC) and gas
chromatography—mass spectrometry (GCMS), may be obscure and inconclusive.
The reason behind such ambiguous GCMS or GC data set is change in the distribution
of components of original samples and spilled material due to weathering processes
like biodegradation, evaporation and photooxidation. Depending on the environmental conditions, after the spill, evaporation may lead to remove volatile compounds,
and water washing may lead to remove soluble components like hydrocarbons in
aquatic environment. Simultaneously, biodegradation may change the distribution of
compounds. Therefore, correlation of sources and spilled material requires selective
parameters that should be insensitive to environmental conditions (Lu et al. 2015).
Chlorine isotopes are widely used for the study of chlorinated contaminants like
PCBs, dichloro-diphenyl-tricholoroetane (DDT), and dioxins in the environment.
Hunkeler et al. (2005), discussed plume study data of chlorinated hydrocarbon. The
dehydrochlorination of 1,1,2,2,PCE to TCE was found to be predominant pathway.
Some studies showed enrichments of
13 C in VCE and cis-DCE are indication of
dechlorination and compound-specific isotopes analyses (CSIA) data permitted to
determine the rate of bioaugmentation. Hence, we conclude that stable isotopes are
useful to monitor natural attenuation.
15.5 Sustainable Risk Assessment and Groundwater
Impact/Status
Water security is a considerable concern, especially in countries facing remarkable
population growth and vulnerable climate. There can be many reasons to consider
sustainable water management as an important environmental assessment tool like
less groundwater recharge, deterioration of groundwater quality due to seawater
intrusion, high rainwater runoff, and increased wastewater generation by growing
population. Water recycling through aquifers is an important study for sustainable
water management. Managed aquifer recharge (MAR), to replenish groundwater in
urban environment plays a major role worldwide. It depends on natural treatment
processes which take place within the aquifer like infiltration, sorption, degradation,