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

NYC 9/11 Public Portal Document

RESPONSES TO COMMENTS FROM THE NYC DEP BUREAU OF SEWERS - 4/15/87 \ 1. On Drawing No. C-7. The following note will be added: All elevations refer to Penn R.R. Tunnels Datum, which is 297.275 feet below Mean Sea Level as established by the U.S. Coast and Geodetic Survey at Sandy Hook, New Jersey. To convert elevations to Borough of Manhattan Sewer Datum Plane, subtract 300.025 feet. For example: EL. 302.10 Penn R.R. Tunnels Datum -300.025 EL. 2.075 Sewer Datum Plane On Drawing Nos. C-8, C-9. C-10, C-11, C-12, C-13 and C-13A, the following note will be added: "For converting Sewer elevations to Borough of Manhattan Sewer Datum Plane, see note on Drawing No. C-7". 2. On Drawing No. C-11, 11th Avenue is shown in the screened background. On Drawing Nos. C-9. C-IO, C-13 and C-13A, 11th Avenue is beyond the limit of coverage of these drawings. 3. Drawings C-7 to C-13A showed invert elevations that were surveyed in duly 1986 specifically for this project. These elevations are slightly higher than shown on the North River I & I study and are believed to result from siltation that has occurred since the construction of the sewers. We will add the as built data from the North River I & I study to the above referenced drawings. 4. Legend for proposed catch basin will be revised to differentiate from that for the proposed manhole. 5. The elevations shown on Drawing S-28 at the connections of the existing sewers and the proposed siphon facilities are existing and proposed elevations. Wherever only one elevation appears at any manhole on that drawing, the upstream and downstream ends have the same invert elevation. Notes will be added to clarify your comment on the above referenced drawing. 6. The limits of abandonment of the existing sewer in the 34th Street will be added to Drawing No. S-28. 7. On drawing No. C-11, the proposed 15" E.S.V.P. is a sewer, and the third catch basin in series has been changed to a manhole instead 8. The existing sewer to be picked up at manhole No.l was shown on Drawing No. S-28 by four dashed lines. For greater clarity we will add a note labeling the four dashed lines as "EXISTING SEWERS". The location of sewer to be plugged at manhole No. 2 will be shown on Drawing No. 28 and the following note will be added at that location: "BREAK AND PLUG THE EXISTING SEWER".

NYC-WTC_000165390