The board of approvals (BoA) for special economic zones (SEZ) is likely to extend tomorrow the validity of in-principle clearance to Reliance Industries' Maha Mumbai SEZ under the new rules that limit its size to 5,000 hectares."The extension of validity has been under the new rules that limit the size of a SEZ to 5,000 hectares," a government official said. Reliance had earlier proposed Maha Mumbai SEZ over an area of 10,000 hectares and received in-principle approval for project in August last year.The amendment to rules notified in March had reduced the validity of in-principle approval to one year from three years previously, but BoA was given the powers to extend the validity by two more years.Besides the Maha Mumbai project, the BoA, headed by Commerce Secretary G K Pillai, will take up eight fresh proposals. These include five zones for in-principle nod and three for formal approvals. Of these, two relate to Infosys Technologies which wants to set up IT and ITES zones near Hyderabad. The biggest zone coming up for in-principle approval is by Ispat Industries, which wants to set up a 1,012 hectare multi-product SEZ in Maharashtra's Raigad district.SEZ proposals of Genpact, Enfield Infrastructure and Adarsh Prime Projects would also be placed before the BoA for formal approval. While Genpact is seeking nod for a 10-hectare IT and ITeS SEZ in Jaipur, Enfield has proposed a 16-hectare IT and ITeS SEZ in West Bengal.So far, the government has given formal approval to 383 SEZs and in-principle nod to 183. Of the 383 formal approvals, more than 135 have already been notified.