APPENDIX B. 309 



and banking the coffer-dam to the lines and levels established by the Engineer, will be 

 classified as "Coffer-dam filling." The material used in filling will be measured in 

 place, but without deduction for the space occupied by the cross-ties and cross-walls. 

 The material used in banking will be measured by cross-section, in place, but none 

 placed outside the established lines and slopes will be paid for. The riprap will be 

 paid for as "Riprap," by the cubic yard in place. The material excavated for the 

 foundation and shore connections of the coffer-dam will be classified as "Excavation," 

 and will be estimated for payment by cross-sections as provided for in par. 22. 



All labor and material not mentioned, but required in the construction of the 

 coffer-dam, shall be furnished by the contractor at his own expense and covered by 

 his prices on other parts of the work. 



Payment for the coffer-dam, subject to the ten per cent deduction,* will be made 

 on monthly estimates, but no payment will be made for any material lost or damaged 

 during construction through the fault or negligence of the contractor, or through his 

 failure to properly complete, fill, bank, or riprap the coffer-dam or any portion of it 

 after having commenced work thereon, except where such failure arises from natural 

 causes. 'All repairs or rebuilding, the necessity for which shall arise from natural 

 causes, and which shall be ordered by the Engineer, will be paid for at the contract 

 prices for the material used, estimated as provided in these specifications for the orig- 

 inal construction: provided, however, that all repairs or work of any kind, rendered 

 necessary in any manner through the fault or negligence of the contractor, or done for 

 his convenience by permission of the Engineer, shall be executed by the contractor at 

 his own expense. 



15. Removal. The contractor will be required to remove all material forming 

 the down-stream arm of the coffer-dam to a depth of i foot below the lower miter-sill, 

 except where it will be covered behind the lower land cribs. He must also remove all 

 material forming the river arm below the dam to a depth of 2 feet below lower pool level, 

 and all material forming the upper arm and the river arm above the dam that may 

 come within 10 feet of the upper pool level, together with all portions that may inter- 

 fere with any of the construction. The material removed need not be preserved. All 

 this work must be done at his own expense, and the time of removal and the place of 

 deposit for waste material shall be prescribed by the Engineer. 



16. Cement-testing Shed. A shed, for the purpose of testing cement, and a cement 

 storehouse, shall be built by the contractor according to the drawings. The construc- 

 tion of these buildings shall be completed as soon as practicable after beginning work, 

 and at least two months before the contractor will be in readiness to use cement. Any 

 necessary repairs to these buildings during the continuance of the contract shall be 

 executed by the contractor at the request of the Engineer. The lumber entering into 

 their construction and their repairs will be estimated and paid for as "Coffer-dam 



* See paragraph 30, under " General Conditions." 



