Construction of Production Tube Well at Commando Training Centre, Lethpora.

Amount

Construction of production tube well by way of ; Drilling /boring of Skeletal Pilot bore hole ;-Drilling of skeletal pilot bore hole of 125mm diameter (minimum) up to a depth of < 150 meters, below ground level in all sorts of soil/Strata In case the pilot bore hole turns out to be a success in terms of water bearing strata sufficient enough to be declared feasible for construction of production tube well by the hydro geologist. i) Broad band specification of pilot bore hole:- a)Dia of pilot bore hole = < 125mm b)Depth of pilot bore hole = < 150m The same pilot bore hole is to be reamed to a full fledged production well. In case of failure of pilot bore hole in terms of :- 1. Non presence of water 2. Severe water quality issues( presence of Arsenic and other chemicals harmful for humans) No further construction/Execution shall be taken and the bore hole or the execution of production well shall be declared as a failure. The pilot bore hole in case of failure shall have to be properly capped by the agency with cement mortar to avoid any incidents/accidents if left unattended.

Construction of Gravel Packed Production Tube Well :- After successful completion of the pilot hole based on water test and Geologist’s report, the same pilot hole is to be reamed to the required size and depth into a full-fledged production well . Broad band technical specification of the pilot hole and production well by and as required by the drilling procedure. 1) Production Well :- a) Dia of production tube well = > 500/550 mm b) Depth of Production well = <150 mtrs ( May increase or decrease with condition of report. The construction of production tube well casing design and the No on Screen /length of each screens and positioning thereof shall be the full responsibility of firm/ agency strictly as per the hydrologist’s report and lithology description framed.

PProviding , Lowering and fitting of Heavy duty M.S .Casing pipe ERW as per relevant IS codes . The jigs and fixtures for lowering the casing pipe are provided by the firm. Providing and fitting of Bail Plug/ Bottom Plug of required dia at the bottom of the Pipe assembly of the well. Technical Features of Pipe; Min dia of Casing Pipe = 250 mm Length of each pipe = 3 mtrs Thickness of Pipe = > 08 mm with +ve tolerance of 10 cms Max. depth of Pipe = < 150 Mts Slotted Pipe …….. At appropriate Aquifer Zones Acceptable make for Pipe …. Jindal/ Prakash Surya/ TATA/ E.R.W/ H.F.I.W. IS code for pipe ----- IS 4270: 2001(Grade Fe410) third Revision

For 250 mm dia MS Blind Pipe

For 250 mm dia MS Slotted pipe

Providing and Shrouding of Pea Gravel as per IS: 4097-1967.of assorted size around annular space between the casing pipe and the well surface has to be filled with a gravel pack to act as a filter medium. Quantity >30 Cum

Development of Tube Well :- a) Development of Tube Well shall be done in accordance with IS 11189 - 1985 .The job includes Charges on accounts of complete development of the well after completion of drilling /boring and lowering of M.S. Casing pipe and filling of pea Gravel if required (in Case of Artificial gravel pack ) . The compressor used should have pressure ratings of 1100 PSI with a delivery of 300 cfm The job shell include cleaning and stabilization of the well by inserting high compressed Air pressure to remove the suspended /stick/loose material from the casing and in the well bore surface .Development of well by compressor = 04 hrs /mtr of Screen The development has to be carried out in presence of the in charge site engineer and as per the expertise advise consultant hydrologist if needed . Yield Test :- The job shell also include for carrying out yield test of the well by a submersible pumping unit of desired capacity to be decided by the in-charge engineer .All other job’s which have not been specifically specified in the works shell have to be included as required and in accordance with relevant ISBS codes. The grouting and sealing of tube well has to be done to ensure safe sanitary conditions. An apron around the well (mix of M 10 grade) and slopping away from it to protect the well from pollution to be constructed to prevent contaminated water flowing back into it. The casing pipe has to be anchored with the apron by welding ISMC 150 steel bracing with cleats and sufficient welding area 2 metres length each bracing embedded within the apron (4 bracings). The complete well thus completed and is to be handed over to the territorial mechanical Division for harnessing. Technical Specifications; Minimum Run for Compressor ….. 04 Hrs/mtr of screen Yield Test for Water (till desired Results) … Min 30 Hrs (i)Apron size = 2.5 mtrx 2.5 mtr (ii)Apron depth at skirt = 300 mm (iii)Apron depth at well casing =350 mm

M/S CHINAR DRILLERS

M/S SANGAM BOREWELLS