Note on methodology

The Snam Sustainability Report refers to the year ending on 31 December 2011 and maintains the same reporting scope as the previous year, except for the information on corporate governance, which refers instead to the new corporate structure on the date of publication of the Report.

The document includes the information for stakeholders provided in the Consolidated Annual Report, showing physical and monetary data and performance indicators indicative of the entire range of significant social, environmental and economic impacts of Snam’s different activities:

• transportation (Snam Rete Gas S.p.A.);
• liquefied natural gas regasification (GNL Italia S.p.A);
• storage (Stogit S.p.A.);
• distribution (Italgas S.p.A., with subsidiary Napoletanagas).

Economical information presented in this report are drawn from Snams Consolidated Annual Report, while the methods of calculation used to determine the different indicators are described in the specific sections.

In addition, information is provided in the appropriate form on significant events occurring after the end of the year.

To ensure the comparability over time of the indicators deemed most significant and to give the reader the chance to compare the performance obtained, current values have been placed alongside those for the previous two years, using graphs and tables.

The Report is prepared in accordance with the Reporting Guidelines in their most up-to-date G3.1 version, issued by the Global Reporting Initiative in May 2011. The Report’s level of compliance with the standards has been enhanced through more specific coverage of all the “core” indicators. In fact, the group’s self-declared level of compliance, as certified by GRI itself, increased from B+ to A+, the highest grade possible.

Verification of the Report’s reconciliation with GRI protocols is facilitated by the specific table appended to the Report

The process of gathering data and information and preparing the Report was coordinated and managed by the Sustainability unit of the parent company, Snam, in cooperation with the different corporate functions and the operating companies. The publication of the document, simultaneous with that of the Consolidated Annual Report, is subject to approval by the Board of Directors of Snam on 12 March 2012.

This Report has been reviewed by the external auditor engaged to perform the audit of Snams annual report (Ernst & Young) based on the principles and guidelines of the International Standard on Assurance Engagements (ISAE 3000) issued by the International Auditing and Assurance Standards Board (IAASB). The results of the audits performed are included in the compliance certification appended to this report.

Lastly, this year, as is customary, the contents of the Report and further information are posted on the sustainability section of the website, www.snam.it.

Legend:

Following the new organisational structure, Snam has redefined the key performance indicators (KPIs).

KPIs make it possible to monitor specific sustainability targets, from the standpoint of continual improvement.

The pre-set targets and the results obtained during the year are reported in the relevant chapters.

KPI symbols – Activity status

Target achieved

Annual target achieved (KPI with multi-year targets)

Activity in progress

The document contains the codes corresponding to the GRI guidelines, for ease of reference and interpretation.

GRI Indicator Symbols