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HomeMy WebLinkAbout010I Groundwater lmpact Addendum February 9,2012 Mr. David Wayne Johnson Department of Community Development Jefferson County 621 Sheridan Street Port Townsend, Washington 98368 6 LlINl)[]t coNsutTlNc, trc i lll itJ G t, t tl r,, t.r,trl0tiurr P$o t!llwl Sodh l.lFi lbr lt.sl ( urth.lrlrr, lt.l .^Jr-r !i uflr.il lr{tr t{ll: {,'<.$u rf}ll r er&r.A.r/r/l/, (,'d ,\n: c.r,t.rll. .,ttt DTAft PLEASANT HARBOR MASTER PLANNED REORT SEIS GROI,I\DWATER IMPACT ADDENDUM, BRTNNON, WASHINCTON Dear David: \ This tetter presents an addendum to the dEIS Water Supply and Groundwater Impact Analysis, Pleasant Harbor Marina and Golf Resofi, Brinnon, Washington prepared by Subsurface Group in November 2007. This letter has been prepared by the same author as the FEIS report. The previous report described the basis for and assumptions for the potential groundwater impacts under the scope of development for the original resort design concept. This report presents the potential impacts under the new Alternative 2 development proposal asshorvn in Figure I, and compares those impacts with the Alternative I and No Action alternatives, The water balance calculations were performed to estimate the pote,ntial impact to the groundwater resources beneath Black Point; in essence tlrey are performed to estimate the changes in groundwater recharge to the sea level aquifer. A change in groundwater recharge to the aquifer can be used to describe the impacts of the resort to the aguifer system. The water balanoe calculations were performed using climatic data for the area; and calculated the amount of evapo{ranspimtion, runofl and changes in groundwater recharge based on proposed domestic and irrigation \vater uses. The basis for these calculations is presented in our November 2QA7 FEIS report. The proposed water use is within the limitations of the ground and surface water right permits (C2-3M36 and 52-30437) granted by the Washington State Department of Ecology on June 16,2010. The proposed development under Altemative 2 is described in the introduction to the SEIS prepared by you and transmitted to us on December 15,201 I. With respect to groundwater resources, there are feiv changes in the reso( design as the number of residential units has remained the same. The size of the inigation area may also be less, but was held constant for our calc.ulations. The proposed amount of impervious surfaccs has been slightly reduced from 13 to 12 percent. The volume of the irrigation storage pond has increased, but once the pond is full the storage reserv'oir size has no effect on the water balanie. The increase in pervious surfaces and a better understandingofthe cdirstruction phasing of the resoft were incorporated into the original water balanee calculations; these provide an understanding of the potential impacts to the groundwater resources beneath the resort and Black Point. Figure 2 presents the results of the recharge calculations. This figure prescnts the cumulative aquifer recharge on an annual basis during the construction and occupancy ofthe resort. The resort development BENDERCONSULTINC. LLC t e\U!.fitscofl Bhdcttllorualml$o5]!.01 Plsrhtlllbo^Ptl 2012 SEISISEIS flalM H!6or Goradmtu lnprct Add.n{ed0ax I 144-0t Letter to Mr. David Wayne Johnson February 9,2012 PageZ schedule was based on a possible timeline of construction events and the proposed staging presented in your December 15,2011 project description. Market and otherfactors may change this timeline; however, with the resoft components as designed, the ultimate calculated recharge for any stage of the resort development will be the samE. Figure 2 indicates thatthe exirtJng (No Action) aquifer recharge is aboutT60acre-feetperyear(shownforyear20l3). Aftercompletionofthereso4aquiferrechargewill be about 804 acre-feet per year under Alternative 2. As shown in Figure 3, the calculated recharge under Alternative I was 822 acre-feet per year. The increase in recharge between the No Action Altemative and Altenratives I and 2 is due to a decrease in vegetation at the site tlrough construction of roads and buildings. Water from precipitation would normally have been consumed by existing trees and plants through evaporation and evapotranspiration processes. As a result of construction of buildings and pavement, runofffronr the irnpervious surfhces is now routed directly to infiltration. In addition, precipitation can now infiltrate more quickly due to changes in soil moisture associated rvith inigation of the golf course, The decrease in aquifer recharge between Alternatives I and 2 is primarily due to the decrease in irnpervious surfaces. However, even under Alternative 2, aquifer recharge will increase by about 6 percent above existing conditions due to construction of the resort. Thank you for the opportunity to be of service. Please call us at (360) 631-5600 if you have any questions. Sincerely, Ssott F. Bender L.H.G,, C.G.W,P Enclosures Figure l. Alternative 2, Overall Site Plan Figure 2. Alternative 2, Annual Cumulative Aqrifer Recharge During Resort Build-out and Completion Figure 3. Altemative l, Annual Curnulative Aquifer Recharge During Resort Build-out and Completion BEN DER CONSULTI NC. I.I,C C[r.fft\S@[ BqdorlD*uo.rlr't0r!t.01 Plcurnt HrriotPH 20ll SEl515ElS Plost Hrrbor Gremdmbt lmprd A&.!dE toir I t41-01 EXISTIN6 ACCESS HIGHWAY 2OO-TT SHORELINE E}IVIRONM MARINA ACCTSS (PRoPOSE0) VISIIOR AND OWNER PARKING JEFf ERSON u5 'olH'6HWAY AND STOP PLEASANT HOUSE EXISIING swtMlilNG STEEP RIPARIAN N ,.@' s dl _ F-LtiA.SANT HARBOR $is$m# David Hamllton Alahltecl wA s230 1-EOO.662-?745 PLEASANI HARBOR Msslrr Plsnncd Resort tr? CO-GEN GAIE A 2t AREA CALCUL^TIONI l'7 ACR6 60tF@1rA56 ANO RIISoRT ARE :2XJiCR6 lM?EtVlOU9: llt PErvlOtS: tr* uiltTt u YAf,II(A ANO !^TITIYE VIU.IGE Af,FI SACRE IYPERVEB I'4 IEIUO(S. Ag UMTS; tt l'.1 @u TElucEs eo 60r*El rlcl: cE mErrsP^ 520 UNITS J(dlo5P. coMMEncr^L MARINA ANO MARITIME VILLAGE 8GA VIEW VILLA &r uNtl5 SFIORETINE Lu* A!'I]|E VETAS.. Ullfi H UIffiE}IAI€ESIJILDITOdDtfi tl^rr0{,r^rfil5n uNlls H llAAlrlllc VILIAGE&I .1Ur,tsil.In lr. cot6rExci4l. t REUXION IIOBEI IIUNTTS r i., lLAI"lOl.Vlfl)msEIirl r: wrs rr-./ EDtBlEiXfAStKii r wrlauwnrlex|sTlxcsrucruB!:l EXISIINO RE$Dtr@& tLE ll^Nl tlAREoR tlOUSE I UNn (lrwruL H(Enr{c Slliucn nE} I MARIIIACCN'EII rosr.ovrRq& 70tAt ntllos,nn^L ts ur{rs tor^L@MxEs.cr & rlmdiF. SEA LEVEL 0 GOLF COURSE AND RESORT SECOND WELL LOCATI0N OPIION A LL t'Iu*Ll .)roJect [\lam6: \ vemll Site g0 hil-------] 900 800 700 600 ee ao o5 soooboL 6l !D ; 400 $ :oo 200 t00 0 0ll0l/13 0t/0r/r4 0l/0t/r5 0li0r/16 tu31n6 ta3ufi ta3vt& tu3ut9 tu3uno ru3ilnt ru30n2 ta30z3 a d. III i $! , I i l I I It I I I I I I I I I ; I R I I r I II i i I I ! !i II{ i i ! 7I I BENDIRF'h-\g3/('rlN\lllrrN(: I lr- tayli,r (:r,.r..:;?rr-' {.-.ir; !!, Supplementary Environmental Impact Statement Pleasant Harbor Marina and Golf Resort Statesman Group Alternative 2 Annual Cumulative Aquifer Recharge During Resort Build-out and Completion ProjcctNumber 1026-02 Figure 2 I 900 800 700 600 4reIoL 19 sooo OD qt Io {mo s E $ roo 200 100 0 0l/01/09 0l/01/10 01/0r/l I 0l/0r/12 ta3v12 w3Ut3 ta3uw tzt3t/ts tu30ll6 tu30lt7 lz30il8 tzBallg lrttltr& I f $ If *o C-I I I I I t I, t I I I i I I i I I I I I I r I I I I I I I I i l i I i I BENDEI].F.Xi-\t6/rr)N(lrlTlN(; llr l.'dir. l'.arr.rn -r,' {-:r'r }{. Supplementary Environmental Impact Statement Pleasant Harbor Marina and Golf Resort Statesman Group Alternative I Annual Cumulative Aquifer Recharge During Resort Build-out and Completion Projeot Number 1026-02 Figure 3 I t I I I I I i i I i I SUBSURFACE GROUP LLC 11220 Fleldstone Lane N.E. Ba,nbddge ,sland, Wast ngton g81 l0 Telr (206) 778-8074 Far (206) 780-5669 MEMORANDUM To: Tom McDonald From: Scott Bender CC: Craig Peclg Carth Mann Date: February 22,2010 RE: REVISED PLEASANT HARBOR GROI]NDWATER MONITORING PLAN This memorandurn presents the groundwater monitoring plan to be used during construction and operation of the Pleasant Harbor Golf and Marina Resorl. The plan is based on several meetings and discussions with the Department of Ecology ard Pacfic Groundwater Group. Groundwater monitoring witl be performed to document lvater qualiry and drawdown conditions related to the development. Figure I presents a map of the existing and proposed groundwater monitoring instrumentation. Two additionalmonitoring wells will be insatlled, labeled M\t/-7 and MW-8 as shown on the attached map., These will be standard 2-inch diameter monitoring wells completed to a minimum of l0 feet below the water table. The existing monitoring wells are labeled on the map MW-2, MW-4, and MW-5. Wells labeled VWP-|, VWP-3, and VWP-6 were geotechnical borings with vibrating wire piezometers installed in thern to measure groundwater pressures. The highest groundwater dernand at the site will be during site development prior to the construction ofthe central pond. About one month before construction and during this period dataloggers will be connected to all of the wells at the site, The program will collect measurements on groundwater pressure and fluid conductivifl, (which can be conelated to salinity). Dataloggers that record groundrvater pressure will be installed at VWP-1, VWP-3, MW-5, and VWP-6, Dakloggers that measur€ both gtoundwater pressure and fluid conductivity (which can be conelated to salinify) will be installed at MW-2, MW-4, MW-7, and MW-8. These units will record groundwater measurements on a 0.5 hour basis. The dataloggers will be downloaded every two months during the construction season estimated from April I to November l, and every three months in the non+onstruction period, estimated November I to April I when there will be minimal welluse. During construction, water quality samples will be collected ft'om the two supply wells and MW-4, MW-7, and MW-8 if an anomalous conductivity trend is observed. The samples will be sent to a water quality laboratory for analysis of chlonide arrl nitrates, SUBSURTACE GROUP, LLC sG0601-03 Memorandum to Statesman C;orporation February 22,2010 Page2 After construction is completed and the occupancy of the resort units commences, all of the dataloggers will be downloaded quarterly. Water quality samples will be collected from the supply wells quarterly. This program will be continued for five years or until the resort has achieved full build-out, whichever is longer; at which time the monitoring plan will be adjusted based on the results of the prograrn. The data will be transmitted to Ecology for their review. Pleasant Harbor will perform a minimum 72-hour aquifer test at each new water supply well installed for the project. During testing the wells will be sampled for electrical conductivity and chloride concentrations. Pleasant l{arbor will use its best eflorts to sample a minimum of nvo coastal domestic wells for electrical conductivity and chloride concentrations twict a year in April and August. Sampling will be dependent upon obtaining the permission, cooperation and availability of the owner of the domestic well. Ecology has identified four potential candidates; Pleasant Harbor will prioritize these wells, and will seek others if the listed wells are not available. For consistency, Pleasant Harbor will atternpt to establish a long-term relationship with those well owners. SUBSURFACE GROUP, LLC sG0601-03 5,6, 7,8 3,13, 16, 34 18, 19'17,26, 26,27, :t1, ,37 48,4941,42 14 6,47,t 50 .) ,Eti: 32 IrI 12, 21, 2/"\, 38,*h 10, ?2, 1 dr4 t 45 Notes: l) Well locations are approximate. Domestic well locations typically to nearest quarter quarter unless better known. 2) See Appendix for well togs ffi- (m Monitoring Well Location (MW = monitoring well; VWP = vibrating wire piezometer Water Supply Well Location Subsurface GrouP, LLC Pleasant l-larbor Marina and Golf Domestic Welland Monitoring Well Locations Grou ndwater I mpact Evaluation Statesman Corporation Project Nurnber sG060l-03 Figure I 36 t 13