Our environmental interventions in Sa Piramide

At the Sa Piramide site, we carried out permanent safety measures at the former landfill site and we are promoting the area's valorisation.

From the remediation of the former landfill to new projects for the territory

Sa Piramide is the name given to an area that was used for the disposal of residues from zinc and lead production at the nearby Portovesme metallurgical hub, which became part of Enirisorse (Eni Group) in 1978. In 1999, the hub was acquired by the Portovesme company, with the exclusion of the former landfill site, subsequently sold by Enirisorse to Singea and, following the merger by incorporation, to Enichem (which later became Eni Rewind). To the present day, as the current owners of the 51-hectare area within the Sulcis Iglesiente Guspinese Site of National Priority, we have undertaken at the former landfill permanent safety measures (MISP) that were certified by the province of Southern Sardinia in 2022. As of 31 December 2024, we have incurred environmental costs amounting to €21 million for our areas. To give new value to the territory, the project for a Plenitude photovoltaic park of approximately 4.5 MW has been submitted, which will be built on the top area of the MISP.

Sa Piramide at a glance

Location: Italy, Sardinia

Start of the environmental interventions: 2004

Sa Piramide past and present

Site history

Start of environmental interventions

Eni Rewind carried out on the site permanent safety measures (MISP).

Landfill acrivities are ceased

The former Sa Piramide landfill site was declared obsolete in 1992.

The site is transferred to Eni

The Sa Piramide area was incorporated into Enirisorse (Eni group) in 1978.

Landfill in activity

The Sa Piramide landfill was in activity between 1971 and 1992 as a waste disposal site for the Portovesme metallurgical hub.

Our activities at Sa Piramide

The former Sa Piramide landfill site was declared obsolete in 1992, and the safety measures carried out included covering it with HDPE sheeting, filling it with soil and vegetation, regulating rainwater, collecting leachate in a storage tank and discharging it into the water treatment plant at the adjacent factory. In 2001, following some problems with the surface insulation, in agreement with the Sardinia Region we have prepared and presented a remediation project with permanent safety measures. Activities was carried out between 2004 and 2009, and included the confinement of the former landfill with waterproof barriers, both at the top and at the sides, the installation of a waste water drainage system and an increase in prevention measures for the groundwater.

We are currently managing the post-operational phase of the permanent safety measures with a 30-year duration. Activities include maintenance of the structure and water monitoring with pumping from three wells outside the former landfill. The piezometers network allows the monitoring of both groundwater and residual water within the safety measures enclosure, below the capping, and upstream of the diaphragm wall. A definitive solution for the management of the site's residual water and groundwater is currently being evaluated with the authorities and the Sulcis-Iglesiente Industrial Consortium.

Vista frontale della MISP (messa in sicurezza permanente)

Immagine 1 – Permanent safety measure interventions (MISP) of the former landfill

Status of the environmental process

In 2009, the permanent safety masures and environmental recovery of the former Sa Piramide landfill was completed. In 2022, the Province issued the remediation certificate. We are currently managing the post-operational phase.