Contaminated sites

What we use

The list of contaminated sites: areas where a survey found pollution above the legal thresholds, or is looking for it, and where a clean-up procedure is open or has been closed with the authority's certification. Each Region keeps its own, and ISPRA, the national environmental institute, collects them for the whole of Italy in the national database MOSAICO.

We use three sources:

• for Lombardy the Region's register, which publishes 1,077 contaminated sites and 3,067 already cleaned up in the public domain, with the site name and street;
• for Piedmont the Region's register, 1,500 sites under a CC BY 4.0 licence, with the point where each one is, the cause and the substances found;
• for all other regions ISPRA's MOSAICO, under a CC BY 4.0 licence: 10,591 procedures in 1,545 municipalities, with the state of each one and, for 8,741, the point where it is.

MOSAICO also gives the boundaries of the sites of national interest (SIN), the large polluted areas whose clean-up is overseen by the Ministry of the Environment: Porto Marghera, Taranto, Bagnoli, Sesto San Giovanni, Brescia-Caffaro and others, 41 in all. They apply across Italy, Lombardy and Piedmont included.

Everything updates by itself every week: Piedmont when the Region remakes its file, MOSAICO on every run. Lombardy publishes one edition a year, and when it comes out we get an alert.

How we use it

The report says how many sites there are in the municipality of the property, what state they are in and how many have been cleaned up. Then it depends on what the source publishes:

• in Lombardy it lists the open sites with their name, type (disused industrial areas, illegal dumps, petrol stations and so on) and street;
• in Piedmont it lists the open sites within one kilometre of the address, nearest first, with the distance, the cause and the substances found;
• in the MOSAICO regions it does the same with the distance and the status of each site, where the position is reliable (see below). MOSAICO has no site name or street.

Where the source makes the distinction, the report keeps sites with clean-up under way apart from those still under investigation, where the pollution is still being looked for, and from those closed because the analyses ruled out the need for a clean-up.

Sites cleaned up are counted but not listed: they are closed cases, and lining them up with the others would make the municipality look full of open problems.

For sites of national interest the report says whether the address is inside the boundary or within one kilometre of it, and what the site is called. Inside a SIN even digging or a new building must follow the rules of the clean-up: something to know before buying.

The rating is never critical: it is worth considering if the home is inside a SIN or if there is an open site within 500 metres, favourable if there is none within 500 metres, informative where only the municipality of the sites is known.

How far from home

The distance is from the point the authority uses to mark the site: it is the authority's figure, not our estimate. For a large area the boundary can be closer than the point, and the report says so. For sites of national interest the distance is from the boundary.

In MOSAICO some regions mark many sites with a conventional point at the centre of the municipality. Those sites count for the municipality but not among the nearby ones, and where there are many of them the report gives no distances: "no site within one kilometre" would be false. Today this happens in Veneto, Trentino-Alto Adige, Umbria, Marche, Abruzzo and Calabria, where the count stays at municipality level.

In Lombardy the register gives the municipality and an address written by hand by different offices over twenty years ("via Pertini", "vie Zama/Salomone"), which is why the count stays at municipality level. Turning that address into a point can be done, but a contaminated site put in the wrong place in a report is much worse than a contaminated site not shown. Meanwhile the street is there, written as the register writes it: anyone who knows the area recognises it.

Where there is no coverage

Sardinia is not in MOSAICO and does not publish an open register: there the report says that we have not looked, which is different from "there are no sites". Sardinia's sites of national interest (Sulcis and Porto Torres) are there, though, and the report flags them.

Limits

• The lists hold recognised sites, meaning those where there has been a survey and a procedure. An area never surveyed is not there, and this is true everywhere.
• The count by municipality describes the municipality, not the street: in Milan there are hundreds of sites and they affect few addresses.
• MOSAICO lacks the boundary of the Milano Bovisa site of national interest.
• To find out whether an area really affects the property you are buying, ask the municipality or the regional environmental agency (ARPA), which hold the file.

Official pages: ISPRA's MOSAICO, Regione Lombardia open data and the contaminated sites register on the Piedmont geoportal.