Trial to establish the feasibility and efficacy of Deep Soil Mixing (DSM) for Main Plant Structures of GHAVP-3 and 4 (Phase-I) at village-Gorakhpur, Distt.-Fatehabad, Haryana.

Filling with available excavated earth (excluding rock) from within the Plant boundary in layers, consolidating each deposited layer by compacting with rollers and watering to achieve required compaction. Quoted rate shall include all arrangements to prevent damage to near by structures, etc. In case of any damage, the same shall be made good by the contractor with no additional cost to NPCIL. Quoted rates shall include site grading / levelling so as to make area workable.

Excavation of the soil using mechanical means/ manual means for lowering the existing Ground Level as per technical specification/ drawing, including making neccesary arrangement for surface dewatering if required. Note :- 1. Quoted rate shall includes all type of exacvation required at the Trial location for installation of DSM column and inspection for leak tightness post DSM installation, including all arrangements to prevent damage to existing DSM Columns. In case of any leakages from walls of the pit, neccesary sealing / dewatering arragement shall be provided. 2. Quoted rate shall also include making necessary arrangement for providing access to the excavated pit and making neccasry arrangement/ sumps for pumping out seepage water (if any). Requisite safety arrangement during excavation & inspection also to be ensured and included in the quoted rates."

Drilling & Coring in soil layer Including collection, handling and stacking/ preservation, transportation for testing till the samples are handed to NPCIL at the completion of Job.

Conducting Standard Penetration test (SPT) using automatic trip hammer in drilled boreholes (in virgin soil/ DSM columns) as per the specification following relevant standard.

Supply & installation of PVC pipe for making observation wells for monitoring of water level. Note: Drilling for observation well shall be paid under item no. 2.1

Obtaining Undisturbed tube / piston soil samples, from all depths of the drilled boreholes, necessary sealing and transporting the same to testing laboratory as per specifications and as directed by the engineer. Note: Bidder should study the sample borelogs to understand the soil type expected to be encountered for sampling. Collection of undisturbed samples will require deployment of special samplers viz. Mazier/ Denision etc. considering the silty sand strata at site.

Cross Hole Seismic Test (CHST) - Conducting cross hole shear wave test (CHST) in borehole in all types of strata/DSM Column at depths of 1 to 1.5 m interval from ground level up to required depth from ground level including preparation of borehole, providing PVC liner, grouting and backfilling with sand after completion of the test etc. all complete as per specification, drawings and as directed by the Engineer-in-charge including conducting the test, interpretation & recommendation of relevant geotechnical parameters and submitting report thereof Note: 1. The test shall comprise of five bore holes (one for the source and four for receivers). For measurement purpose S-R1-R2 & S-R3-R4 shall be considered as one test. One test is equivalent to depth of source borehole as per approved drawing. 2. PVC liner/ pipe shall be provided in all the five bore holes up to a required depth. Payment against this will be paid under Item No 2.6. 3. The cost of drilling bore holes and pluging etc shall be paid separately as per item 2.1 and 2.7 respectively. 4. The deviation survey of all the five bore holes shall be included in the quoted rate. 5. Quoted rates shall include mobilization and de-mobilization of the CHST equipment and its accessories. 6. Rate shall also include cost of Engineer to be deployed for testing meeting the requirements of ASTM D3740. 7. Energy source shall be S-wave shear sparker with Impulse generator for conducting CHST test. Testing agency shall deploy sufficient number of receivers having minimum 3 channels sensor compatible with the energy source so as to conduct test in all the receiver holes simulataneously (S-R1-R2 at same time). 8. Suitable arrangement to prevent choking/ blockage/ damage to PVC pipe duirng ongoing works shall be made by Contractor at no additional cost to NPCIL. In case installed PVC pipes are found damaged/ blocked during testing, suitable arrangements shall be made to make the pipe available for testing at no additional cost to NPCIL.

Providing and installing permanent new PVC casing of suitable size Dia in already drilled hole (in virgin soil/ DSM column) and filling the annular space by bentonite/other suitable material for conduction of Cross Hole Shear Wave test (CHST) as directed by Engineer along with necessary coupling, threading etc. complete, in the above specified drilled holes, wherever asked for by the Engineer. Note: Drilling for CHST shall be paid under item 2.1 & 4.01.