The Parliament Standing Committee (PSC) on Environment in April had directed ASI to submit an interim action plan for restoration of the Taj. The RTI query further revealed that the chemical cleaning (mud pack therapy) will have to be repeated every 6-7 years if pollution is not reduced.

During the meeting of PSC with senior ASI officials, it was accepted that air pollutants, especially suspended particulate matter (SPM), after reacting with marble is masking the original colour and sheen of the monument.

The RTI reply stated that clay pack method is being used presently to remove harmful surface deposits from the marble surface. This method is considered safe as it involves minimal use of chemicals and almost no mechanical efforts, it added.

A senior ASI official said that it would be for the first time that the mud pack therapy of four minarets and dome would be carried out. It will take at least one year to clean the main dome. Likewise, 10 months each would be required for cleaning of four minarets. 12 months have been allotted for dealing with unforeseen suspension of work.

The cleaning of Taj interiors has not been included in the plan, as erection of scaffolding and control of tourists' movement would be major constraints.The RTI reply added that scientific studies and research would be continued for the effective monitoring of the conservation efforts. This will also help modify the existing treatment methodology or to develop better formulation and advanced conservation methods, it said.