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In this study, results about sludge stabilization in reed bed systems (RBSs) after the entire period of operation in two different systems situated in Denmark (Helsinge 42,000 population equivalent (p.e.) - 10 years) and in Italy (La Fontina, 30,000 p.e. - 6 years) were presented. In order to evaluate the process of sludge stabilization, parameters that highlighted the biochemical and chemico-structural properties of organic sludge matter have been determined. The level of total and soluble nutrients, and enzyme activities, parameters related to overall microbial activity, showed that stabilization of the sludge similarly occurred in both RBSs, even though in different landscape ecosystems. The chemical-structural characterization of sludge organic matter highlighted how the processes of stabilization have occurred satisfactorily in both RBSs; in fact, significant levels of pyrolytic indices for mineralization and humification were reached. The successful stabilization of organic matter occurred in both RBSs and was confirmed by the absence of Escherichia coli, and also by the results of organic compounds (polycyclic aromatic hydrocarbons, linear alkyl benzene sulfonates, nonylphenol ethoxylates, di-2-ethylhexyl- phthalate) and heavy metals. © IWA Publishing 2013.

Reed bed systems for sludge treatment have been widely used in Denmark for many years, while in other countries, such as Italy, are more recent and less common. In this study, results about sludge stabilization occurring within beds after the entire period of operation in two different urban wastewater treatment plants situated in Denmark (Nakskov, 30,000 p.e.) and in Italy (La Fontina, 30,000 p.e.) were presented. In order to evaluate the process of sludge stabilization parameters that highlighted the biochemical and chemico-structural properties of sludge organic matter have been determined. In addition, the residual sludge biotoxicity have been investigated through a microbiological parameter, phyto-test, availability of inorganic and organic pollutants. The results showed that stabilization of the sludge similarly occurred in both treatment plants, even though in different landscape ecosystems, as shown by the low content of water soluble carbon and dehydrogenase activity. Moreover, the organic matter humification was demonstrated by the pyrolytic indices of mineralization and humification and by the significant level of humic carbon content. Furthermore, parameters related to sludge biotoxicity have been evaluated. Results about Escherichia coli have shown that the stabilised sludges were sanitized in both treatment plants; moreover, data about germination tests, bioavailable heavy metals and hazardous organic compounds demonstrated that the stabilised sludges were not toxic for environmental purposes.

One of the major specific objectives of AGRIPORT project was to develop the use phytoremediation as an innovative technology to recover dredging sediments using plants (phytotreatment). Through its three years duration AGRIPORT have focused on optimising the decontamination method in two pilot applications in the ports of Livorno (Italy) and Ashdod (Israel). As regards the application in Livorno, the works started on December 2009 with the technical assistance of Livorno Port Authority, that provided the location area, and the University of Pisa - Department of Civil Engineering - that designed the treatment basin. On February 2010 the facility was completely done and equipped with all the hydraulic and electric connections for an automatic irrigation, drainage and monitoring of inlet and outlet water. During May 2010 the facility was planted following this scheme: one area was dedicated only to a grass specie (Paspalum vaginatum), another one was used as control (no plants), and the other two were used for a combination between grass species and shrub species (Paspalum vaginatum in coupling with Tamarix gallica and Spartium junceum). The present document is the deliverable D.2.2 Internal report on chemical and physical analysis results. It describes the actions conducted by CNR for the monitoring of the phytoremediation system in term of decontamination and bio-functional recovery of sediments. In view of this physical-chemical and biological analyses were carried out on sediment treated in the facility. A first sampling was performed in July 2010 (T0) and a second one was performed in December 2010 (T6), in accordance and in time with the content reported in Annex I. A third sampling of treated sediments was performed in June 2011 (T12) and a fourth one was performed in December 2011 (T18). In May 2012 a new sediment sampling (T24) was done considering three different depths: 0-20, 20-40 and 40-60 cm and the chemical, microbiological, and biochemical analysis of the sediments, together with the heavy metals and pollutant organic compounds measurement were carried out. Chemical, physical and biological analyses were performed in CNR-ISE laboratories. For the methodologies used for the analyses, took as reference the first draft of the Deliverable 2.2. The comparison between these data was useful to detect the development of the facility status and AGRIPORT technique success. After 24 months from the experiment set up, the successful of the decontamination, the nutrients dynamic and the activation of microbial metabolism were evaluated.

In this study, phytoremediation was explored as a sustainable reclamation technology for turning slightly-polluted (heavy metals and hdrocarbons) brackish or saline dredged sediments into a matrix feasible for productive use. To test this possibility, two phytoremediation experimentations were carried out in containers of about 0.7 m3 for brackish sediment and in a basin of 80 m3 for saline sediment. The sediments were pre-conditioned by adding an agronomic soil (30 % v/v) to improve their clayey granulometric composition, and by topping the mixture with high quality compost (4 kg m-2) to favor the initial adaptation of the selected vegetal species. Different plant treatments were compared each other and with an unplanted control sediment (C) in order to evaluate the plant efficiency in remediating and ameliorating the agronomical and functional sediment properties. The healthy state of the plants and the characterization of the sediments after the phytoremediation treatment highlighted the effectiveness of the process in remediating (hydrocarbon reduction of about 50-60% and heavy metal reduction of about 25%) and recovering the sediments from an agronomical (chemical) and functional (biochemical) point of view. The obtained product can be referred to as a ''technosoil'' with most characteristics approaching those of a natural soil. Such technosoil can be feasible for several environmental uses, such as plant growth substrate, geo-material for reforesting eroded land or in the bioremediation of polluted degraded sites.

Sludge consolidation reed beds represent an established technology for managing biosolids produced by wastewater treatment plants (WWTPs). In this study, an analysis conducted on the stratigraphy of the sludge consolidation reed bed serving the municipal WWTPs of Helsinge (60,000 p.e., Denmark) are presented. The bed has been in operation since 1996. The analysis was conducted for four months including two consecutive loadings of the bed. The amount of dewatering during the short initial phase was significant and the rehydration of deeper layers was negligible. A clear reduction trend was observed for volatile solids and labile organic matter, which is the first step towards organic matter stabilization and humification. This hypothesis was also confirmed by water soluble carbon, which decreased with the increasing depth and the time of resting. About the N cycle, ammonification and nitrification showed a reciprocal balancing effect, so as to cause an equilibrium between the stable trends of N-NH4 + and N-NO3 - which were similar along the depth and the time of monitoring. The highest values of both parameters were found at the surface, where the combined effect of plant action, direct diffusive oxygen transfer from the atmosphere and high nutrient contents of the freshly loaded sludge was likely more intense.

Sludge stabilisation and mineralisation occurring in the sludge residue within the sludge treatment reed bed systems during periods of operation between 10 - 21 years in three different systems receiving sludge from urban wastewater treatment plants situated in Denmark. Samples were taken in the sludge residues along the entire profiles, in order to compare the effectiveness of the sludge stabilisation process in the three systems. Particular attention was given to the stabilisation process occurring within the reed beds; in fact, parameters correlated to biochemical properties of organic sludge matter have been determined. Statistical procedures were used to evaluate how the biochemical processes influence the quality of sludge organic matter in the three systems. The level of total organic carbon and total nitrogen had a similar trend along the profile: their concentration decreased with increasing depth, reaching very low levels at the deepest layers. The same trend was also observed for the water soluble carbon, N-NH3, b-glucosidase and urease activities, hydrolytic enzymes linked to C and N cycles, respectively: their values decreased dramatically with increasing depth, meaning that the level of mineralisation of the organic matter was higher in the deepest layers. The determination of extracellular enzymes bound to humic substances and humic carbon permitted to evaluate the stabilisation of organic sludge matter, and also allowed to individuate in which ways the sludge was stabilised, in terms of mineralisation and humification of the organic matter.

The aim of this study was to evaluate the effect of a vermicompost (obtained from olive mill wastewaters and cellulose materials) on soil quality and fertility, and on the yield of different horticultural species (Allium porrum L.; Cichorium intybus L., Brassica oleracea). The results showed an improvement in the chemical (increase in total and soluble nutrients) and biological (increase in enzyme activities) soil fertility also with respect to a soil treated with traditional municipal solid waste compost. Moreover, in vermicompost treatments a higher yield (Allium porrum L.; and Brassica oleracea) or equal (Cichorium intybus L.,) to the traditional compost was observed.

In the last years, intense industrial and agricultural activities have led to serious environmental pollution, resulting in a large number of contaminated sites. Several recent research activities have been focused on the application of bioremediation technologies as environmental friendly and economically feasible for decontamination of polluted soil. In this study horse manure (HM treatment) and horse manure plus Populus nigra (var.italica) (HM+P treatment) were used, at real scale level, as an ecological approach to bioremediate a soil historically contaminated by heavy metals (Pb, Cr, Cd, Zn, Cu and Ni) and organic contaminats (polychlorobiphenyls and total petroleum hydrocarbon). After one year, the phytotreatment was effective in the reclamation of the polluted soil from both organic and inorganic contaminants. A reduction of about 80% in total petroleum hydrocarbon (TPH), and 60% in polychlorobiphenyls (PCB) and total heavy metals was, in fact, observed in the HM+P treatment. On the contrary, in the HM treatment only a reduction of about 30% of TPH was showed. In the attempts to assess both effectiveness and evolution of the remediation system toward a biologically active soil ecosystem, besides the pollution parameters, also parameters describing the evolution of the soil functionality (enzymatic activities and protein SDP-page pattern) were investigated. Dehydrogenase activity is considered an indicator of overall microbial activity and can be involved also in the decomposition and detoxification by contaminants. Moreover, differences in protein pattern on SDS-page could be useful to identify the effects of the pollutants on protein composition. In this study, a stimulation of the metabolic soil processes (increase of dehydrogenase activity) was observed in the planted compared to untreated soil. Finally, preliminary protein SDS-page results have permitted the identification of proteins that have been recovered in planted soil with respect to an untreated soil; this may become a basic tool for improving the biogeochemical status of soil during the decontamination. In addition, the combination of mass spectrometry and protein database could identify the microbial populations that are active in soil decontamination.