Land may become contaminated as a result of past practices in the management of materials, for example, through inadequate containment, accidental release or poor disposal practices. Depending on the circumstances there may be potential for harm to the environment. GSK employs global standards that require, among other things, the identification and management of contaminated land. GSK enters into agreements with relevant authorities to assist in the remediation of contaminated land when required. GSK then directs the remediation of contaminated areas to levels that are consistent with the expected future use of the land and with local regulatory requirements.

Following GSK's earlier investigation of operational sites in the UK, it was determined that the majority featured low probability of contamination, or low hazard and pollution potential if contamination were present. A group of seven sites remained for further study, of which five are thought to require some remediation and two of these sites are undergoing partial or full decommissioning in preparation for sale.

In the US, GSK is currently involved with some 25 sites where sites must be remediated. These include 13 sites on the US Environmental Protection Agency's National Priority List (NPL) of so-called "Superfund" sites, as well as several sites listed under various state programmes. Most of these sites are abandoned waste disposal sites where waste generated from a GSK facility may have been found among waste generated by several (in some cases, hundreds) parties and often over many years.

In dealing with remediation sites over nearly 20 years, GSK has always cooperated with the government upon notification and confirmation of our connection to a site, and worked with the other parties to effect the remediation. GSK pays its fair share according to an agreed allocation of costs among the parties participating in the remediation. Even in cases where we cannot initially agree on an allocation, we employ an interim allocation to allow the work to go forward and settle final allocation later. GSK generally participates in groups of companies organised to remediate sites in accordance with its allocation, among other factors. Participation varies from monitoring the activities of a committee to taking a leadership position in the committee.

Since 1980, GSK and its heritage companies have spent over £100 million on remediation of more than 50 sites. Many of these sites will require long term operation and maintenance (O&M) for systems such as groundwater treatment facilities. For "mature" sites - where "construction" is complete and O&M may or may not be required long term - GSK and its corporate partners assess the possibility, and implement the return of such sites to beneficial use, such as community parklands.