North Access Tunnel W. 33rd St. To w. 38TH ST

NYC 9/11 Public Portal Document

IC. Show the existing columns and footings along the route of the proposed sewer and inverted siphon. Slww the details of reinforcement in all the chambers and inverted siphon. 17. The design of the inverted siphon does not meet D.E.P. criteria. An additional siphon for peak sanitary flow should be provided. This was conveyed to you on phone previously and in a meeting held on June 23, 1987.

18. A meeting was held on July 2, 1987 in which details of underpinning as shown on drawing Nos.S-4S and S-46 were discussed. Comments were given at this meeting and it was agreed that plans will be revised accordingly.

19. The title sheet should have a N.Y.S.P.E. seal and signatures.

Add the following notes: i) All proposed drainage work shall be done in conformance with the latest standards of the Department of Environmental Protection. ii) All existing standard basins should be repaired, if damaged, and cleaned, and flushed as necessary, to make them operable. Damaged castings should be replaced. Existing non-standard basins at locations where basins are required shall be replaced with new standard basins. Ui) Abandoned drainage structures as shown on contract plans are to be cut down two (2) feet below subgrade and filled with compacted clean sand. All apex basins are to be abandoned and fall into this category.: Basin connections not required shall be bulkheaded at both ends. iv) All existing sewer manholes within the contract limits should be adjusted as necessary, so that they will be flush with the finished grades after completion of the work. Any of these manholes which have damaged, worn or non-standard frames and covers should be provided with new 27" castings in accordance with the latest standards of N.Y.C.D.E.P. including any necessary modifications of the manhole masonry. Any damage to the manhole caused by this work shall be repaired, or replaced by the contractor, as directed by the engineer, and at no cost to the City. v) Where the height of an existing manhole permits more than one (1) basin connection to be made on the same wall, special precaution shall be taken to protect the struct­ ural integrity of the manhole. The minimum clearance between the outside walls of any two basin connections or between a basin connection and a sewer, vertically or horizontally, shall be 12 inches.

NYC-WTC_000165351