bids are invited for excavating trenches by mechanical / manual means of required width for pipes, cables, etc including excavation for sockets, and dressing of sides, ramming of bottoms, for all depth, including getting out the excavated soil, and then returning the soil as required, in layers not exceeding 20 cm in depth, including consolidating each deposited layer by ramming, watering, etc. and disposing of surplus excavated soil as directed, within a lead of 50 m: all kinds of soil: pipes, cables etc. exceeding 80 mm dia. but not exceeding 300 mm dia. providing and laying in position cement concrete of specified grade excluding the cost of centering and shuttering all work up to plinth level: 1:2:4 ( 1 cement: 2 coarse sand ( zone-iii ) derived from natural sources: 4 graded stone aggregate 20 mm nominal size derived from natural sources ) . providing and laying in position cement concrete of specified gradeexcluding the cost of centering and shuttering all work up to plinth level: 1:4:8 ( 1 cement: 4 coarse sand ( zone-iii ) derived from natural sources: 8 graded stone aggregate 40 mm nominal size derived from natural sources ) . centering and shuttering including strutting, propping etc. and removal of form work for: foundations, footings, bases of columns, etc. for mass concrete. providing and laying non-pressure np2 class ( light duty ) r.c.c. pipes with collars jointed with stiff mixture of cement mortar in the proportion of 1:2 ( 1 cement: 2 fine sand ) including testing of joints etc. complete: 150 mm dia. r.c.c. pipe. total quantity : 333