Distribution
and Persistence of Organochlorine Micropollutants in
Marine Sediments from Daya Bay, China
Khalid
Maskaoui,
College of Science, Biology Department, Shantou
University, Shantou, China, Tel: +86-754-2902083, Fax:
+86-754-2902829, Email: maskaoui@yahoo.com,
kmaskaoui@stu.edu.cn
Junliang Zhou,
The School of Biology and Environ. Science. Sussex
University. Falmer, Brighton BN1 9Q1, United Kingdom, Tel:
+44-1273-606755 Fax:
+44-1273-677196, j.zhou@sussex.ac.uk
Yali Han, College of Science, Biology Department, Shantou
University, Shantou, China, Tel: +86-754-2902768, Fax:
+86-754-2902829, Email: ylhan@stu.edu.cn
Daya
Bay is a semi-enclosed bay located in the East Coast of
Guangdong Province, Southern China. It is one of the
largest bays in Guangdong Province, with a coastline of 92
km, and an area of 600 km2. It has been one of the main
aquacultural areas, thanks to its excellent water quality
coupled with rich biological resources. However, since
1980s, there has been rapid expansion of aquacultural,
industrial and agricultural activities in the area, with
simultaneous developments in the construction of harbours,
transportation and tourism; such dramatic changes have
adversely affected the water quality in the bay. This is
particularly true since the operation of a nuclear Power
Station (NPS) at Daya bay since 1993. Large quantities of
cooling water are discharged into the bay and in addition,
no data is available on the level of persistent organic
pollutants (POPs) such as polychlorinated biphenyls and
organochlorine insecticides in the area. The objectives of
this study were therefore to determine the levels of
selected organochlorine micropollutants in the marine
sediment and to identify the factors that may control the
distribution and persistence of organochlorines in the
area.
Samples
of surface sediments collected from Daya Bay, China have
been analysed for 12 polychlorinated biphenyl (PCB)
congeners and 18 organochlorine insecticides, using gas
chromatography electron capture detection. Total PCB
levels varied from 0.85 to 27.37 ng/g dry weight. The
levels of total organochlorine insecticides were in the
range 2.43-86.25 ng/g dry weight. The levels of total
hexachlorocyclohexanes ranged from 0.32 to 4.16 ng/g dry
weitght. For the sum of dichlorodiphenyltrichloroethanes (DDTs),
their levels were in the range 0.14-20.27 ng/g dry weight.
The distribution profiles of these contaminants suggest
that there are a number of sources contributing to total
contaminant burden in the bay, including soil runoffs,
wastewater discharges, sewage outfalls and shipping
activities. Ratios of DDT/(DDE + DDD) indicaterecent
inputs of such chemicals into the bay. The results,
therefore, provide important information on the current
contamination status of a key aquacultural area in China.
Use
of a Bench-scale Treatability Study to Determine
Cost-effective Disposal Methods for
Contaminated Sediments
S.
Dore, Conestoga-Rovers and Associates, 2055 Niagara Falls,
New York 14304, Tel: 716-297-6510, Fax: 716-297-2265
Email: sdore@craworld.com
D.
Pope, Conestoga-Rovers and Associates, 2055 Niagara Falls,
New York 14304, Tel: 716-297-6510, Fax: 716-297-2265
Email: dpope@craworld.com
J.
Smith
Conestoga-Rovers and Associates, 2055 Niagara Falls, New
York 14304, Tel: 716-297-6510, Fax: 716-297-2265 Email: jjsmith@craworld.com
A.F.
Weston Conestoga-Rovers and Associates, 2055 Niagara
Falls, New York 14304, Tel: 716-297-6510, Fax:
716-297-2265 Email: aweston@craworld.com
Cost-effective
disposal is a major concern for sediment remediation
projects that require removal of sediments.
To meet landfill criteria sediments must pass tests
for hazardous waste content, hazardous waste leachability
and residual moisture content.
A knowledge of these parameters is essential before
the cost of the remediation can be estimated.
CRA has developed a laboratory treatability study
procedure to obtain the required information rapidly.
An example of the application of this procedure is
a treatability study that was conducted on heavy metal
contaminated dredged sediment from a site in Michigan
Three
sediment samples were obtained and composited to form a
sample that would be representative of site conditions. To
be acceptable for disposal at a non-hazardous waste
landfill the sediment samples must pass TCLP, stability
criteria, and the paint filter test. Sediment leachate
data showed that the sediment met only TCLP criteria,
therefore stabilization was necessary. Ten polymers were
evaluated for their effect on solids settling. A sediment
slurry was settled with and without polymer treatment and
the supernatant and settled solids were collected. A
filter press was used to dewater the settled solids to
produce a filter cake, which was tested for water
content, TCLP metals, and the paint filter test. The
effects of solidification agents on the settled solids
were also evaluated. The agents tested were Portland
cement, fly ash, and cement kiln dust. The results showed
that untreated settled solids did not meet landfill
stability requirements. The ability of polymer treatment,
solidification and filter cake from dewatering using a
filter press to meet the landfill stability requirements
will be described. Based
on the results of the treatability study a cost-effective
technique for sediment treatment and disposal was
determined.
Studies
on the Heavy Metal Pollution in Sediments by Using
Sediment Quality Index
Dr. Syeda Azeem Unnisa, Lecturer, IST, Centre for
Environment, Jawaharlal Nehrru Technological University,
Kukatpally, 72, Tel: 040-23155413, Fax: 040-23156128,
Email: syeda_azeem@rediff.com
Prof. AVS. Prabhakar Rao, Guest Faculty, IST, Centre for
Environment, Jawaharlal Nehrru Technological University,
Kukatpally, 72, Tel: 040-23155413, Fax: 040-23156128,
Email: avspr@rediffmail.com
The present study is spread over couple of seasons. In
this context an attempt is made to classify the conditions
and pollution status of sediments of lakes as Excellent,
Good, Poor, Very poor and Unfit.
The sediment samples showed high amount of lead,
cadmium and nickel when compared to iron, manganese and
copper. Based on this classification only one lake
sediment was found to be excellent and remaining lakes
sediments were unfit.
Studies
of Trace Metals and Natural Radionuclides in Bottom
Sediments from around a Campos Basin Oil Field Offshore
Platforms
Sergio
F. Jerez Veguería,
Universidade Federal Fluminense, UFF, Instituto de
Química, Dpto. Química Analítica, Outeiro de São João Batista
s/n, Campus do Valonguinho, Centro Niterói, RJ
24.020-150, Brazil, Tel: +55 (21) 2629-2142, Fax: +55 (21)
2629-2143, Email: sfjerez@rdc.puc-rio.br
José
M. Godoy, Pontifícia Universidade Católica do Rio de
Janeiro, Depto. Química. Rua Marquês de São Vicente,
225 Gávea, CEP 22453-900, Rio de Janeiro, RJ, Brazil and
Instituto de Radioproteção e Dosimetria, Comissão
Nacional de Energia Nuclear. Av. Salvador Allende s/n -
Jacarepaguá, CEP 22780-160, Rio de Janeiro, RJ, Brazil,
Tel: +55 (21) 3411-8073, Email: jmgodoy@rdc.puc-rio.br.
Offshore
oil and gas production can cause a potential impact to the
marine environment. Large volumes of aqueous waste are
produced during oil and gas production and, normally,
these are discharged, following treatment on the platform,
to the sea. In this produced water the high concentrations
of metals and naturally occurring radioactive materials
(NORM) are often found and this contaminants are being
introduced or have entered the sediment and water column
near production sites. In this work the offshore bottom
sediments samples from the Bacia de Campos oil field were
analyzed for Al,
V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ba, Pb, As, U, 226Ra,
228Ra and 210Pb. The determination
of trace metals in sediment samples for total, after
microwave digestion, and leachable fraction with 0.5 M of
HNO3 was done by Inductively Coupled Plasma
Mass Spectrometry (ICP-MS) in TotalQuant mode with 115In
and 205Tl as internal standard. Al, Fe and Ba
were also determined by Inductively Coupled Plasma Optical
Emission Spectrometry (ICP-OES). 226Ra and 228Ra
were determined in surface sediments sampled around the
effluent discharges, either their total content by
g
-ray
spectrometry of 214Bi and 228Ac,
respectively, either by gross alpha and beta counting
after leaching with EDTA. The total 210Pb
activities in sediment samples were determined by
g
-ray
spectrometry with auto-absorption correction. The results
show that there are chemical differences between the areas
around the two studied platforms. The results of the
principal component analysis (PCA) pointed out a possible
preferential deposition of the metals in the Southwest
direction. This verification is in agreement with the
supposition that the environmental effects would be
registered in the Northeast-Southwest alignment due to the
action of the Current of Brazil. The sedimentation rate in
one studied site was 0.28 cm.yr-1, what can be
attributed to the contribution of particulate material of
fluvial origin in this region. In general, the trace
metals and radionuclides concentrations in the analyzed
sediments are in agreement with the expected values for
unpolluted marine sediments.
Investigation
of the Changes of Permeability, Physical and Chemical
Characteristics of Sediment Basins for Artificial Recharge
in Bagh-e-Sorkh Region, Shahreza, Isfahan
A.
Goudarzi, Postgraduate Student of Irrigation, College of
Agriculture, Isfahan University of Technology, Iran, Tel:
00986652322041, Email: ahmad_goir@yahoo.com
S. S. Eslamian, Associate Professor, College of
Agriculture, Isfahan University of Technology, Iran, Tel:
00983113913082, Email: saeid@cc.iut.ac.ir
R. Nazari, PhD Student of the Graduate Center of City
University
of New
York, USA, Tel: 212-650 8427, Email: RNazari@gc.cuny.edu
In recent decades, with
continuous droughts, demand for water has been increased
and per capita renewable-water has been decreased in many
countries which are faced with water limitation and
scarcity. Considering the particular hydrologic conditions
in Iran, seasonal floods and high intensity of rainfall
are important and using artificial recharge projects is
unavoidable to augment the water resources. The major
problem with recharging projects is the entrance of
sediments to the recharging basins. Due to depositing the
floating particles, it is necessary to treat and recover
permeability of the basins. In this paper, we compare
permeability of the basins for artificial recharge in
Bagh-e-Sorkh region of Isfahan. To measure the
permeability, four double rings have been installed in
different places for each basin’s bed and the
permeability was measured. Also, some samples were taken
from sediments of the region and some of their physical
and chemical characteristics, such as soil texture, EC,
and nourishing elements, were measured. The results showed
that permeability for beds of the pounds highly decreased
and had fallen to less than 10 (the first basin) to 25
percent (the fifth basin) of the initial value. Comparing
the physical characteristics of sediments from the
different pounds indicates that with increasing distance
from the system starting point, the sediment depth is
decreased and on the contrary the fine sediments are
increased. Because of this, the sediment’s thickness was
not so much influential in amount and the pace of the
final permeability.
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