=========================== FOLLOWING PSMSL DOCUMENTATION ADDED 11-Jun-1991
Plum Island         960/136 RLR(1967) is 8.7m below BM4
=========================== FOLLOWING PSMSL DOCUMENTATION ADDED 16-Feb-2012
Plum Island is now an Historic station. Last data received was that for 1968. The original RLR diagram referred to BM 4 3.280m relative to gauge datum. At some stage this was obviously superseded by BM TIDAL 4 STA II 24 4.234m relative to gauge datum. There is now no mention of BM 1 on the NOAA website.