Submarine wastewater discharges: dispersion modelling in the Northern Adriatic Sea

Background, aim and scope   

Opposite interests must coexist in coastal areas: the presence of significant cities and urban centres, of touristic and recreational areas, and of extensive shellfish farming. To avoid local pollution caused by treated wastewaters along the Northern Adriatic coast (Friuli Venezia-Giulia and Veneto regions), marine outfall systems have been constructed. In this study, the application of a numerical dispersion model is used to support the traditional monitoring methods in order to link information concerning the hydrodynamic circulation and the microbiological features, to evaluate possible health risks associated with recreational and coastal shellfish farming activities. The study is a preliminary analysis of the environmental impact of wastewater treatment plants (WWTPs) with submarine discharge outfalls. It also could be useful for the water profile definition according to the Directive 2006/7/EC on the quality of bathing water and for the integrated areal analysis (Ostoich et al. 2006), to define the area of influence of each submarine discharge point.     

Rapid screening of different chelating agents in the lead extraction from cathode ray tube (CRT) funnel glass

The cathode ray tube (CRT) glass is one of the most important problem that afflicts the electronic waste disposal whose solution lies in the identification of efficient and ecofriendly processes to detoxify and reutilize lead-contained funnel glass. This study is focused on a rapid screening of different chemical and mechanochemical processes to reduce lead content in waste CRT glass downgrading the risk correlated to it. In particular, as a possibility to clean waste CRT glass, treatments of lead-containing glass with different chelating agents (EDTA, NTA, ATMP, EDTMP and HEDP) were performed to evaluate their extractive capabilities. Furthermore, the influence of the grinding, the chelating agent functional groups (polyamino-carboxylic acid, carboxylic acid, and polyamino phosphonic acid), and the time and the temperature on lead content reduction were analyzed. ESEM and EDS analysis were performed on all the samples to evaluate the lead amount before and after the treatments.     

Risk reduction measures of large wood accumulations at bridges

Environmental Fluid Mechanics - Bridges with and without piers are prone to large wood (LW) accumulations during floods, possibly resulting in an upstream backwater rise, local scour, or...     

Microscale Toxicity Identification Evaluation (TIE) for interstitial water of estuarine sediments affected by multiple sources of pollution

Estuaries in the world are affected by different contamination sources related to urbanisation and port/industrial activities. Identifying the substances responsible for the environmental toxicity in estuaries is challenging due to the multitude of stressors, both natural and anthropogenic. The Toxicity Identification and Evaluation (TIE) is a suitable way of determining causes of toxicity of sediments, but it poses difficulties since its application is labour intensive and time consuming. The aim of this study is to evaluate the diagnosis provided by a TIE based on microscale embryotoxicity tests with interstitial water (IW) to identify toxicants in estuarine sediments affected by multiple stressors. TIE showed toxicity due to different combinations of metals, apolar organic compounds, ammonia and sulphides, depending on the contamination source closest to the sampling station. The microscale TIE was able to discern different toxicants on sites subject to different contamination sources. There is good agreement between the results indicated in the TIE and the chemical analyses in whole sediment, although there are some disagreements, either due to the sensitivity of the test used, or due to the particularities of the use of interstitial water to assess the sediment toxicity. The improvement of TIE methods focused on identifying toxicants in multiple-stressed estuarine areas are crucial to discern contamination sources and subsidise management strategies.