Circumvesuviana (Torre Annunziata – Castellammare di Stabia) Environmental monitoring

As part of Pizzarotti’s contract for the design and execution of works to double the Circumvesuviana line from Torre Annunziata to Castellammare di Stabia (works including the construction of the new “Stabia Scavi” station, consolidation of the slopes and the construction of a tunnel and upgrading of the Castellammare Centro Station) the VDP company is carrying out the service of executing the environmental monitoring plan.

Environmental monitoring is foreseen throughout all the phases of the project, starting with the baseline characterization in the ante-operam phase, continuing with the monitoring during construction that is currently underway, and at the end of which the post-operam phase will follow.

Specifically, the components that were examined are:

• Atmosphere: monitoring mainly aims to assess the emissions generated by the construction site and to verify the effectiveness of the mitigation measures. The monitored parameters include PM10, PM 2,5, nitrogen oxides, carbon monoxide, and other relevant air pollutants.
• Noise: the objective is to assess the acoustic impact of the construction site activities and the operation of the railway line. Monitoring is carried out during the pre-construction (ante operam), construction, and post-construction (post operam) phases to detect any exceedances of the regulatory limits.
• Vibrations: the main sources of vibration include demolition, excavation and railway traffic. Monitoring is aimed at minimizing disturbances to sensitive receptors and ensuring that vibration levels remain within acceptable limits.
• Vegetation: the surveys focus on the phytosanitary condition of vegetation in the areas affected by the project, with particular attention to the entry and exit zones of the tunnel. The objective is to detect any alterations and ensure environmental restoration after the completion of the works.
• Groundwater: monitoring activities focus on assessing the chemical quality and hydrological stability of underground water resources, considering the potential impact of construction activities.
• The ante-operam phase began in January 2020 and VDP company was responsible for organizing and initiating the environmental monitoring activities for all the environmental components subject to monitoring. For each environmental component examined, periodic reports were submitted to the client, describing the state of the environment in the area during the preparatory phase, at the start of the works, and on a quarterly basis, throughout the construction phase.
• The monitoring activities are expected to conclude in 2026, during the post-operam phase.

Specifics of the study

Vegetation monitoring is carried out annually, through two different types of surveys:

• Type A surveys: Identification and mapping of the phytocoenose in the affected area, with the classification of homogeneous vegetal physiognomies according to the Corine Biotopes system.
• Type B surveys: Assessment of the phytosanitary condition of individual valuable trees in the areas near the construction site, using the VTA (Visual Tree Assessment) method.

As part of the Type A surveys, areas potentially affected directly or indirectly by construction activities were mapped, all characterized by the presence of vegetation typical of deciduous oak forests. As part of the Type B surveys, individual trees located near the future construction sites were identified, and their health status will be monitored in the next phase.