Soil-contamination from toxic explosive residues at military bases throughout the world, is a major
environmental concern. A strong candidate for TNT soil-contamination within Greece, is the military
base/airport of Maleme in Crete. While soil sampling was in progress new routes of trace analysis for
explosives in soil were explored. Solid-phase micro-extraction (SPME) was used to selectively preconcentrate
analytes prior to GC/MS. In the preliminary experiments (effectuated on water-spiked samples)
optimization of the SPME technique was achieved by controlling parameters such as sampling
method, salt content and sample agitation. As immersion of the SPME fiber was found to be more efficient
for extracting most analytes of interest, a pretreatment step was introduced for the soil samples
which simply converted them to water samples. The developed SPME protocol was able to screen
explosives in spiked-soils, in concentrations well below the certified reporting and detection limits.
Adsorption and removal of commercial dyes were studied in aqueous suspensions of fly ash mixtures
with a sandy clay loam soil of low organic matter content. The commercial dyes, acid orange 7, acid yellow
23, disperse blue 79, basic yellow 28 and direct yellow 28 represent the widely used nitroazo structures.
Batch and column experiments were carried out at equilibrium conditions for concentrations of
dyes between 5 and 60 mg l-1. The logarithmic form of Freundlich equation gave a high linearity and
the k constants are increasing with the increase of fly ash content in adsorbent mixtures and the affinity
between the adsorbent surface and adsorbed solute. The mean removed amounts of dyes by adsorption
batch experiments in soil mixture with 20% fly ash content were up to 53.0% for acid yellow 7,
44.9% for acid yellow 23, 99.2% for direct yellow 28, 96.8% for basic yellow 28 and 88.5% for disperse
blue 79. The removal of dyes from column experiments decrease with the increase of the solution concentration
form 10 to 50 mg l-1 at 20 °C, showing the process to be highly dependent on the concentration
of the solution. The mean removed amounts of dyes by adsorption on columns of soil mixture
with 20% fly ash content and for initial concentration of dye solutions 50 mg l-1 were up to 33.8% for
acid yellow 7, 59.4% for acid yellow 23, 84.2% for direct yellow 28, 98.2% for basic yellow 28 and 60.3%
for disperse blue 79.
Water resulting from the dewatering process of petroleum storage tanks was treated in a pilot separator
to investigate the effectiveness of the combined action of a coagulant (aluminum sulfate) and a
cationic flocculant (NALCO 71403). Central composite design of experiments was used to construct
second order response surfaces for the turbidity, suspended solids and oil content as optimization parameters.
The coagulant and flocculant concentrations and pH were used as design factors. The separator
constructed for this purpose proved to be suitable for fast and reliable investigation of multivariable
systems and for search of the optimum via statistical design of experiments.
The paper presents some interesting results of metal speciation studies employing Anodic Stripping
Voltammetry (ASV) applied in a dynamic natural system such as the brakish marine interface formed
between the polluted waters discharged by the Koumoundouros lake and the marine ones of the Gulf
The distributions and behaviour of various forms of Pb, Cd and Zn have been followed seasonally. Four
categories of dissolved species were identified (very labile, moderately labile, slowly labile and inert),
as well as particulate species. It was found that their relative contribution and patterns are determined
by three main factors: salinity, pH, and the presence of dissolved organic carbon. Increasing salinity
stimulates formation of very labile chloro-complexes, while increasing pH stimulates the formation of
inert species and particulates. A considerable part of slowly labile species seems to be metal complexes
with organic ligands.
A so called Exact Form of the Maximum Likelihood Method is used to obtain directional spectrum
estimates from a 3-meter NDBC discus buoy, part of the Surface Wave Dynamics Experiment
(SWADE) field array. The method was used to look at the response of wavefields to turning winds with
various wind shift gradients. For slowly turning winds, the spectrum was found to smoothly adjust to
the wind changes. As the wind shift gradient increased, a portion of the spectral energy was found to
be decoupled from the wind while the bulk of the spectrum smoothly adjusted to the new wind direction.
Finally, for even larger wind shift gradients, the preexisting spectrum was completely decoupled
from the wind and decayed separately, as a new spectrum consistent with the wind direction was generated.
These observations confirm theoretical results previously obtained from a third generation
wave model. The relaxation of waves in turning winds was investigated using a simple relaxation model.
Correlation coefficients obtained in this study are higher than previously published studies, especially
for lower values of the wave age, and a relationship between the relaxation parameter and the wave age
This work illustrates the use and some related results of Artificial Neural Networks (ANNs) for data
quality control of environmental time series and for reconstruction of missing data. ANNs are applied
to the following problems: i) short and medium-term predicting of air pollutant concentrations in urban
areas, ii) interpolating and extrapolating daily maximum temperature, iii) replacing time distribution
with spatial distributed information (pollutant concentrations at different measuring sites). Observed
versus predicted data are compared to test the efficacy of ANNs in simulating environmental processes.
Results confirm ANNs as an improvement of classical models and show the utility of ANNs for
restoration of time series..
The purpose of Sustainable Development raises the following basic question: Which indicator
should be used to identify the human activities that are contrary to this purpose?
In this paper it will be shown that Entropy Generation constitutes this Indicator. To this purpose, we
will use three examples where Entropy Generation takes place and demonstrate that this generation of
entropy is always contrary to Sustainable Development.
A forecast of future human activities will be then presented which will demonstrate that large Entropy
Generation will continue. Sustainable Development can be thus achieved only by entering an Era of
Reduced Entropy Generation, which requires however drastic changes from Institutional policies to
our own values and way of life.
The present work argues that sustainable tourism is essential to the long-term survival of the tourism
industry in Europe. Sustainable tourism may be regarded as a means of redressing economic imbalances
between European regions and nations without producing adverse environmental, social and cultural
effects on host communities. Conflicts between the development of a local economy and the interests
of outside investors from elsewhere among EU member nations must be resolved in the best
interests of the local people and the environment. The degree to which profits are expropriated from a
local area or region is a particular concern. The transnational character of tourism businesses makes
necessary a European-wide policy, where the quality of life and natures conservation will obtain a premortial
Pump-and-treat (P&T) is one of the most common methods for remediation of groundwater contaminated
by hazardous wastes. However, this method suffers from serious disadvantages, due a series of
subsurface processes. Using experimental data and mathematical model simulations, the role of sorption/
desorption and dissolution of non-aqueous phase liquids on the effectiveness of P&T remediation
was examined. The results showed that the remediation of groundwater depends directly on the physical/
chemical properties of the contaminants and the hydrogeology of the site. With the exception of
water-soluble contaminants occupying relatively small parts of relatively homogeneous and water-permeable
geologic media, the remediation of groundwater contaminated by hazardous waste using P&T
is, for all practical purposes, impossible and prohibitively expensive.
Fly ash (FA) and fluidized bed ash (FBA) solutions were evaluated as amendments for acid-disturbed
lands, more specifically for treating acidic and metal contaminated soil. While titrating the ash materials
with different volumes of acid, pH changes were monitored as a function of time and the acid volume
added. The release of metals from the ash materials as a function of pH was also monitored. An
acid mine drainage (AMD) solution was equilibrated with ash materials and clay and the metal removal
from the solutions evaluated. Both FA and FBA produced solutions of high initial pH. However, FBA
indicated a higher buffering capacity resulting in a steeper titration curve. The system pH strongly
impacted metal release from the ash materials. The leaching experiment indicated a pattern whereby
the basic metals (Ca and Na) were released at higher pH and the acidic metals (Fe and Cr) at lower
pH. Limestone had almost double the buffer intensity but a lower initial pH than ash materials.
Comparison of ash materials with two types of clay revealed that ash materials were better alternatives
for treating acidic and high metal content wastes. Albeit both ash materials were able to treat AMD,
their overdose could lead to trace metal accumulation with negative consequences to the environment.