http://www.nsf.gov/geo/oce/envcomp/nj-seismic-research/summer2015/amended-mountain-nj-margin-ea-final-revised.pdf
Pages 57 and 58 are significant for sport divers:
“(5) Direct Effects on Recreational SCUBA Divers and Dive Sites and Their Significance
No significant impacts on dive sites, including shipwrecks, would be expected. Airgun sounds
would have no effects on solid structures. The only potential effects could be temporary displacement of fish and invertebrates from the structures.
Significant impacts on, or conflicts with, divers or diving activities would be avoided through
communication with the diving community before and during the survey and publication of a Notice to Mariners about operations in the area. In particular, dive operators with dives scheduled on the shipwreck Lillian during the survey would be contacted directly. That dive site represents only a very small percentage of the recreational dive sites in New Jersey waters. In June and July 2013 and 2014, there was only one AIS-identified dive boat passing through the survey area. No dive vessels were observed in the survey area during the ~13 days that the Langseth was there in July 2014.
The New Jersey Council of Diving Clubs (NJCDC) suggested that a 145-dB low-frequency sound
limit could provide a suitable margin of safety for divers. Based on in situ measurements collected during 2014 using seismic streamer data and analyzed by Crone (2015, pers. comm.), a 145-dB level would be ~14 km (~7.5 nm) from the vessel. This 145-dB value is extrapolated from measured values; measured values at 160-dB and 180-dB distances were significantly lower, by 30–50%, than modeled values.
Except for the Lillian, there is only one potential dive site in a 14-km buffer around the survey area, an unidentified wreck very near the outer edge of the buffer in >60 m water depth. The 14-km buffer is conservative, as it is around the entire survey area, not the vessel itself. The vessel, which would be constantly moving, would be a minimum of 14 km from a point on the edge of the buffer, but could be as far away as ~65 km from that point when it is at the far end of the survey area.”
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