A GIS-based Decision Support System (DSS) was developed to select the appropriate interpolation
technique used in studying rainfall spatial variability. The DSS used the ArcView GIS platform by
incorporating its spatial analysis capabilities, the programming language "AVENUE", and simple statistical
methods. The system consists of a series of modules and can be applied in spatial studies of
other hydrological parameters. A test case from the country of Switzerland is used to demonstrate the
applicability of the system. This should aid in better input to hydrological models.
Citizen concerns about environmental management practices will usually lead to public attention and
legislative proposals. This paper intends to assess the behaviour of potential environmental polluting
industries. In order to accomplish this objective, a survey composed of twenty-five questions was sent
to large, medium and small enterprises located in Portugal. To analyse the data obtained, statistical
methods – descriptive, bivariate and multivariate – were applied using SPSS 10.0 (Statistical Program
for Social Sciences). The results of the present research allow the conclusion, with a confidence level
of ë=95%, that potential polluting companies can be aggregated into five strategic groups, each one
pursuing a distinct environmental strategy. Each group has specific characteristics that are reported
namely in terms of identification variables and environmental strategic factors. The data analysis
reveals that large environmental efforts are directly related with the company size. It also shows that
most of the companies that are investing to protect the environment are those that include environmental
facts (accidents) in their accounts.
Over the last decades intensified agricultural production is applied in the northern coastal part of
Korinthos Prefecture (Peloponnese, Greece). An aquifer system occurs in the recent basin deposits,
which consists of unconsolidated material, namely sands, pebbles and fine clay to silty sand sediments.
A network of production boreholes and wells distributed over the studied region were sampled in June
1998 and the waters analyzed for major ions, nitrites and ammonia. Quality deterioration was detected
and attributed by crop overfertilization and use of abandoned shallow wells as septic tanks, inducing
increased nitrogen compound concentrations. Nitrates are noticeable throughout the entire region rendering
most of the analyzed waters improper for human consumption, as concentrations by far exceed
50 mg l-1. Mean nitrate concentration in the groundwater is 74 mg l-1 and the standard deviation 72. In
general, low nitrate concentrations were observed in wet seasons.
In this paper a review of most recent practices in the field of Risk analysis are presented. Then the
available data for oil spill incidents in the area of Crete covering the period 1995-1999 are analysed and
discussed in detail. Risk analysis tables are produced in order to formulate the spatial, temporal (yearly
and monthly) risk of an incident, the correlation with the prevailing wind fields in both northern and
southern Crete, and the possibility of an early intervention the relevant authorities located at the major
port of Heraklion. Then the possible risk of an oil spill incident is discussed in relation to various sensitive
social or financial activities as well as to environmentally protected areas. Finally a formula is proposed
and applied in order to combine the various risks from an oil spill incident. As it was found,
northern Crete and especially the marine areas of Heraklion and Chania are most prompt for an oil
spill accident and its consequences. The area of Sitia follows. Southern Crete seems to be less vulnerable
to such risks.
Although noise is a very common nuisance in Greek cities, information on actual noise levels in streets
is sparse. Here, noise measurements at five main streets of Thessaloniki, Greece for about five weeks
are presented. Ten minute, one hour and daily average noise levels were calculated. Traffic noise levels
were significant in every examined street during the study. In all streets, the diurnal variation of
noise levels and traffic volume exhibited significant correlation, with r2 up to 0.92. Noise measurements
at two heights in one street showed a difference of around 14 db between the 1st and the 8th floor. The
noise levels difference between working days and weekends was around 1-2 dB during daytime, but it
changed sign during the late night hours. The latter can be attributed to night-life recreational traffic
during weekends. Noise levels from 7:00 to 24:00 were around 63-66 dB in the 1st and 2nd floors of all
four streets where measurements were made at these floors. In these cases, the quietest period was
between 4:00 and 6:00, but even then, in three out of four cases noise levels were above 60 dB.
Although no exceedances have been observed, the mean daily values, i.e. Leq(08:00-20:00), are close to
the national limit of 67 dB(A). This exploratory measurements show that Thessaloniki has a traffic
noise problem, which is likely to become more acute, if the 6% annual increase in traffic volume experienced
during the previous decade is to continue.
Á mathematical model is applied to calculate the water circulation in the marina of Latsi in Cyprus.
The flow field in the marina shows the general behavior of coastal, wind driven flows, being strongly
influenced by the characteristics of the entrance of the marina. The small dimension and the location
of the entrance do not permit the inflow or outflow of significant flow rates, thus resulting to long flushing
times. The use of two openings has been investigated. Computations show that the first opening
plays a very important role, while the effect of the second opening is only of local and minor importance.
This behavior is due to the orientation and the position of these openings with respect to the
entrance. The use of the first opening results to a significant increase of the flow-rate passing through
the inner part of the marina, which increases the magnitude of the velocities and reduce the flushing
times. The use of the second opening leads to a significant short-circuiting path of the flow between the
opening and the entrance. The first opening has been proposed for construction.
The US Environmental Protection Agency (USEPA) recently introduced more stringent arsenic regulations
by lowering the maximum contaminant level (MCL) to 10 ìg l-1 (ppb) arsenic in drinking water.
During the present study, an iron solution injection sand filtration process was designed and tested to
selectively remove arsenic (As(V)), chromate (Cr(VI)) and cadmium (Cd(II)) from aqueous solutions
down to trace level. Bench scale sand columns with a chemical feeding system were used to conduct the
filtration study. The filtration results demonstrate that As(V) could be removed by ferric solution-treated
sand filters from 2,000 ìg l-1 (ppb) down to less than 5 ìg l-1 (ppb) using two sand filters connected
in series (two stage filtration). During the filtration, ferric concentrations in the first and second filters
were maintained at 5 and 2 ppm, respectively, through a continuous injection scheme. Bench scale filtration
results suggest that Cr(VI) could also be effectively removed by injection of ferrous solution
into the sand columns. Similar ferric treatment of the sand columns also significantly increased Cd(II)
removal. Batch adsorption experimental results suggest that when solution pH is lower than 8, arsenate
can be removed by iron-treated sand. Arsenate-saturated sand can be regenerated using a high pH
(pH > 12) solution. Scanning Electron Microscope (SEM) and energy dispersive x-ray (EDX) studies
suggest that very little amount of Fe on the sand surface was dissolved when the sand was regenerated
using a dilute NaOH solution (pH = 13).
Laboratory column tests were conducted to study the efficiency of lignite fly ash barriers in removing
heavy metal ions, such as Fe, Zn, Mn, Ni, Cd, Co, Al and Cu, present in high concentrations in acidic
leachates produced in mining and waste disposal sites. The experimental configuration comprised two
40 cm long plexiglas continuous flow columns installed in series. An upward flow of synthetic acidic
solutions spiked with high concentrations of contaminants was maintained in order to simulate field
flow rates and residence times. Sampling ports fitted along the column walls allowed sampling and provided
information on geochemical mechanisms within the barrier and contaminant degradation rates
in the presence of the reactive material.
The geochemical speciation/mass transfer computer code PHREEQC and the MINTEQ database
were used for geochemical modeling of the process.
The experimental results underline the potential of lignite fly ash permeable reactive barriers to
remove almost completely, over a long period, high loads of inorganic contaminants from very acidic
leachates. The main mechanisms involved in contaminants removal are adsorption at the surface of fly
ash and the produced hydrous iron oxides, precipitation and co-precipitation. The toxicity of the reactive
material at the end of the treatment period, regarding all heavy metals studied, is limited.
In this experimental study some measurements and their analysis are presented concerning the polluted
water effluent disposal in the sea water. The wastes are disposed through the round openings of a
submerged in the sea diffuser, in the form of turbulent jets which are mixing (diffusing) with the sea
water. Three inclination angles (to the vertical) of the jets are examined, ö=15°-45°-75°, and at any
angle three Froude numbers are also examined, Fro=4.8-17-25.3. The results are combined with previous
results by the author for 90°≤φ≤150°.
A Web-node has been created in order to address the specific needs of the small and medium enterprises
(SMEs) of three important economic areas in the Mediterranean region, the food, textile and
hotel sectors. The node provides important information on the market structure in the relevant sectors,
environmental technology issues and legislation, as well as Diagnostic Tools allowing the selfevaluation
and benchmarking of SME's environmental performance.
Environmental performance is evaluated on the basis of the business operational data. A limited set
of environmental indicators is being calculated, and performance is compared to that of its business
competitors, as well as to international standards and "Best Available Techniques".
The diagnosis procedure identifies potential environmental problems in the daily operation of the
companies. The system suggests actions of minor and/or greater cost which could improve environmental
performance and calculates the potential benefit from the decrease of the operational cost.
The overall objective is to assist SMEs in increasing their competitiveness and thereby their position
in the market.