Section 10(2)(a) in The West Bengal Government Land (Regulation of Transfer) Act, 1993
(a)the building, if any, constructed by the lessee on such Government land shall be taken over by the State Government at such valuation as may be made by the competent authority on the basis of the cost of construction of such building less depreciation at the rate in vogue or at the market value of such building, whichever is less, and