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HomeMy WebLinkAboutLog145 ..... .~ e - J .. October 2,2002 File No. 24-99-014-005-05 !D) ~<<: ~ u \'U ~ 1m !fl) OCT ~ 4 11I2 lilJ Ms. Shandra O'Haleck NOAA Fisheries 510 Desmond Drive SE Suite 102 Lacey, W A 98503 JEFFERSON COUNTY DEPT. OF COMMUNITY DEVELOPMENT Subject: Port Ludlow Marina Expansion COE Permit No. 2001-101151 Dear Shandra, As we discussed at our on-site meeting of September 17, 2002, Port Ludlow Associates agrees to the following condition regarding the measurement of noise impacts from use of an impact hammer during pile driving as part ofthe marina expansion project: 1. Underwater sound levels will be monitored at3 meters depth and 10 meters distance from the pile driving site. If hydroacDustic monitoring from thefirstfive piling do not indicate sound levels exceeding 150 dB (re: IflPa)at three meters depth and 10 meters distance from the pile, no additional hydroa co us tic monitoring is needed as pile driving continues. The energy to drive the first five piles shall be representative of the maximum energy used on the subsequent piles. If levels exceed 150 dB (re: 1 flPa) 50% of the time or less but does not exceed 180 dB (re: 1 flPa) during the first five piles, pile driving may continue along with continued hydroacoustic monitoring or, at Port Ludlow Associates option, pile driving may continue without hydroacoustic monitoring with the use of an appropriate sound attenuation minimization measure as discussed below. If levels exceeded 150 dB (re: 1 flPa) more than 50% of the time or exceeded 180 dB (re: 1 flPa) during the first five piles, pile driving may only continue with the use of an appropriate sound attenuation minimization measure as discussed below. Port Ludlow Associates shall notify the COE and NOAA Fisheries of the hydroacoustic monitoringfrom thefirstfive piles within 72 hours. 2. Based on the outcome of the above describedhydroacoustic monitoring, an appropriate sound attenuation minimization measure, such as one of the following, shall be employed. '. Methods to minimizethe underwater soundpressure level may include reducing the force of each strike, or attenuating the underwater sound by enclosing the Pile in an air bubble curtain or pile sleeve. .,"",.,".".l.~~. ~ Engineers p tanners Surveyors Woshington Oregon Alosko Reid Middleton, Ine. 728 134th Street SW Suite 200 Everett, WA 98204 Ph: 425741-3800 Fox: 425741-3900 .... - . e e J " . Ms. Shandra 0 'Haleck NOAA Fisheries October 2, 2002 File No. 24-99-014-005-05 Page 2 3. A report shall be submitted to the COE and NOAA Fisheries within 30 days of completion of the project that presents the results of the hydroacoustic monitoring conducted during the project. The following data shall be provided in the report: size and type of pile; approximate energy supplied to the pile; frequency and amplitude of the underwater sound; angle of the pile; water depth; distance from shore or bulkhead; and type and depth of substrate. It is our understanding that this condition is related only to use of an impact hammer - if a vibratory hammer is used, the condition will not apply. We also understand that if, prior to the time this project goes to construction, NOAA Fisheries or other regulatory agencies have new information which demonstrates that noise will not be an issue with the size of piling proposed, that this condition will not apply. Thank you for your work on this project. If you have any further questions or disagree with the condition or our understandings as stated in this letter, please let me know as soon as possible. Sincerely, Reid Middleton, Inc. ~~ Shannon Kinsella, P .E. Senior Engineer sjs\24Wf\99\0 14Portludlow\PLA WORK\NMFSlttrpilingcondition.doc cc: Susan Glenn, U.S. Army Corps of Engineers Randi Thurston, W A State Department ofFish and Wildlife Josh Peters, Jefferson County Dept. of Community Development Mark Dorsey, Port Ludlow Associates >~:~~-2;~ ~