Attachment A

Erickson [ IWt't'lin! IDC'.

CM.. BAA SpillNoHcaIion 1l-21G!iWOlD No 1813125CNSONay 22, 2013

Rt!MNOir WH!or chd101f91lPh_ I1l-' 1/VIIWtyO1-4701 Bodeg.a Higtlwa)!s.bastopaI CA 95472APN 02G-12fl..OOe

s.-~sIIerKidu'Vi...,... and Winery"707 \me HillRoadSeba5IIIpaI CA Z4n707.322.1328 823-8103 winery

Corrml!l'ltary on Insp4tdion ,..,an by Stann« Fear. EnviromMntat SclMlist NCRWQC8

FumpH Watar Volu• A topographic SWVf!yof the n.nar ofb pond" was completed November 12. 2013 uSing .an

assumed bMchmar1c ~n. It was s~ May 15. 2013110deIiKmine amount of rpunped from stonGe. InIIIrmittIentGala pain ..,. coIedId with survey gur .andentItred in CAD.whIn a diQitaI terrain rnodeI_s CI"UIiId. 0nIHa0t coniot.n __ dawlaped from h DTM. as __~ far m.aUnum and minimum lion. M ximum ....,alicn was detennined by a~ terrace at maximum water liM. Mini •••.•m .!*Valionwas dMHmineci by measuring 1M pip.GUllet elevatiOn in 1M baCDmof the pGftd. Mirimum etw ticn is also camistert Idh propo.1iollalmuslRlMnts of h pipe oullet sIrucIan reI.atr...1O __ IiM taken from Feiler's Im.age 7 datedApril 11. 2013..

o From 1M impaundlMlll tcpagr,a,phy mod ••• m.ax and min water .c.vations ~ wiIhwaler pumped from SUllage are 45.8 ·"0.4 = !l.4· drawdcMn.. 8aMcI on evalu.3\ion of l'illCftfMflta!elttvalion conIDurs" fIMI •••. cischarge _ 3.02-O.3a = 2.M acre fHlThis is equivalent iO883.325 - 110.215 =8a7.11 0 gal.

Discharge Redllctian due to StocIIpand SIor.aaR• The existing s1Dckpond is shown on .• pnHlCIIlslI\ICIicn siIe lIlpOgJ3Fhy map created in 2009 using

aria! tedriqu. by Michael W. 8IOoks and As~ lS uUlg 2' contours.. Tt.map was~mented by leveling IIlN5I.ftf1l1!11ts J.anllal}' 18.201410 detennine pipe spiIw~ invert elevationAllalive 110VIa top of~kmenL 'T'M 20IlQ ~ swfac» cbscuntd h ~inwrt.. soside5Iopes -- p!'Iljedad at 3H: 1V in CAD. c:onsis-t.nl will ui5Wlg lie"•.•• to a depth of G"belowspihRy invert in orditr 10 dIM!Iop supp/ltmental contours necessary forf!oStimaling tDt..a1~wlume. Att.achItd drawings .MId 5p(lNdsheet ~lions incicale that the !itac:lpond capacity isabau 0.61 _ tNt. equi¥ lent 1101ge.500 gallons..

• Mr. Kistler indica1u that fle sIiDckpondwas KMntiaIlw' M1pty at ••• of iniIiaI puII1)ing of the m.ainIMeNOir. Itmpty at tirM of initial JUlllling .II 1200 GPm (_ MIow «ordiscuuion of rMit). itwouldrequn about 2.8 hours of ~ing before pond awrftow woutl oc:aJI'. Di~ to the dcMmslreameft nnelwouldbe I1!duced by tJ1estockpond s!Dagnoll.Wne. to a¥ lie of967.1OD-108,!iOOaeee.eeo "allons..

IIaIIiaI WaW QualIty Cndts• Direct 4IVidence of p.mped discharge "'r tuIbidiy at fttiMian of drawdown is not avai r..

Anecdotal fNidellClt from Mr. Kis1IItr and Mr. MaIinIr indicates the watB was cINr at time of inili.alpunping. (verify statement) 1M first ineNrMnt of pumped w ••. would "...... bftn exp~ to lad!.tulbidily. becaLl54t agitation .wi mixing had not_ accumtd. CclnsefyatiYelyestimating the first 0.8

P.O. Box 4046. Valley FOld CA 1M972-0448 107.7D5.24Q18VoicefFax ericksonO P-Ml

PAGE 10

Kisller Vineyards, 14701 Bodega Highway, Sebastopol CA 95472Reservoir Drawdown EvaluatIOn on Unnamed Tributary and Salmon CreekEnckson Engineering Inc Volley Ford CA 94972-0446

Page 2.

Jonuaryl9,2014

foot (elevation 45 8 - 45.0) of drawdown would remain clear implies that the first 148,000 gal wouldnot have caused turbidity increase in the receiving water

• Subsequent pumping occurred as water quality dechned. Pumped discharge was to the stockpond,which would also function as a sediment detention basin Based on the stockpond volume ofW8,500 gallons, the pumped throughput would have a residence time of 198,5009 1200 gpm = 165min, about 2 75 hours.

o For a pond depth of 6' the theoretical suspended particle settling velocity in calm 'later In2.75 hours would be 6'j(2.75 hr x 3600 sec'hr) = 0 000606 fIIsec.

(, Using an empincal method for relating setlhng veloCity to particle size indicates bycomputatJon that portides of up to 0.016 mm (mid-range silt in USDA ctassincanon) wouldseUle With the available residence time. In reality, turbulent flow would keep some suchparticles in suspension, particularly If the detention basin charactenstics were short cirCUiteddue to How rates. Cloys at 0.002 mm or less would not be expected to settle out in theavailable time frame

• Total discharge Rows with potential for negative impacts to downstream channels would be reducedby the first increment of clear water 668,600 -148,000 => 520,600 gallons with potential for excessturbidity

Water Pumping Rate• The pump used for drmvdown ISa Wacker PT6l T unit rated at 0 - 1300 gpm dependlllg on Total

Head.': The pump is 69" high, with the center of the discharge port at 63"" The pump was located at the top of the large pond levee, with a suction fine extended to

the water, and later the existing pond dram line used for pump discharge.'" The pump generates suction lift from waterline to pump dIscharge elevation as port of

Total Head.,j Based on pump geometry and reservoir geometry, the Total Head varied from 16.3' to

22.8' of 11ftas drawdown increased.c The pump curve was consulted to observe that the operational range of the pump at

governed RPM would be between 1180 and '1220 gpm, perhaps averagmg 1200 gpm.Removal of 867;110 gal from the large pond to stockpond and downstream channels at 1200 gpmwould require 723 mill, or about 12 hours of operation.

Creek Flow Ratios by NTU Dilution• The ratios of turbidity readings upstream, lateral input, and downstream can be used to estimate

nows from the lateral creek relative to the main stem of Salmon Creek ThIS assumes good mixingand uniform steady state flows.

c April '10dilution is oboutl0.2 Salmon Creek: 1.0 Unnamed Tributary based on NTU ratios.c April II dilution is about 6.5 Salmon Creek: 1.0 Unnamed Tributary based on NTU ratios.o The results generated using April 10data are questionable due to tributary NTUs of that date

exceeding source NTUs one day earlier.

Unnamed Tributary April 2013 Bas. Flow Estimation• Feiler Image 13 (p.17 4!11I13) and Image 17 (p. 194115113) show in the background the 6'x6

concrete box culvert located under Bodega Highway above the sampling pool In the UnnamedTributary. In each photo, a waterfall is shown across the enure floor of the culvert

• The box culvert was field inspected 111812014 and appears to have a longitudInal slope of about1%. A minor cross slope at the invert discharge shifts trickle nows to the east side of the outfall.At time of inspection. water now cross section at the lip was about 24· wide on the east end, witha maximum depth of about·.', tapering to zero Row in the center of the culvert. To achieve /lowacross the entire culvert as shown in April, water depth would need to be about 1.75' on the eastand perhaps .25" on the west, averaging an inch across the culvert.

PAGE 11

Kistler Vineyards, 1470 I Bodega Highway, Sebastopol CA 95472Reservoir Drawdown Evaluation on Unnamed Tnbutary and Salmon CreekEnckson Engineenng Inc Volley Ford CA 94972-0446

Page 3.

January 19, 20 , 4

• Manning's equauon for a 6' wide concrete channel at 1°. slope was evaluated, and suggests theApril 2013 background Row In the unnamed tributary was on the order of 570 gpm, as seen inImages 13and 17.

Unnamed Tributary Pumped Flow Impacts• The spill discharge ioconon is +-1870' upstream by channel to the confluence of the 'Unnamed

Tributary- (Un creek• The UT reach is on additional +-3930' by channel to ils conRuence with Salmon Creek. Salmon

Creek IS therefore +-5800' or 1.098 miles from the sma" pond source of turbid water.• NTU Samples taken 4/10/13 seem questionable How can the unnamed tributary value of 2140 NTU

exceed lhat of the source (Kistler small pond 1256 NTU; rauo = 17<Fo) taken one day later and over amile downstream?

• The unnamed channel has a slope of aboul 9813800 per the Kistler property 2' topo map Channelwidth is greater than that of the box culvert, perhaps 10'. The channel SUbstrate is grovel, cobble,and occasional boulder with estimated ManOlngs.n=.040. Manning's equallOn suggests that thebackground 570 gpm flow depth based on these assumptions would have depths averaging about1.2'-16' as the channel width Varied from 10' t06'. There would also be narrower and deepersections expected in a natural channel.

• Adding an incremental now of 1200 gpm from temporary pumping would Increase now to 1770 gpmand would increase water depth. Total depth on average would be about 2.4' - 3 2' as channel Widthvaried from 10' to 6'

• Punped 110\.\1 amounts to about 213 of total now under such conditions. One would therefore expectabout a '113 dilution in source-denved turbidity under such conditions.

• Flow depth could not rapidly increase or decrease, due to the stage-discharge nature of the In-streamwater storage requirement caused by increased depth.

• Neglecting the first 1870' of channel, the unnamed tributary is about 3930'long. For a 6' bottomwidth and a flow depth Increment of (32-1 6 = 1.6') the stored volume would be 3930x6x1 6'12 =3144 ft~3 or about 23,550 gal. At 1200 gpm input rate, it would take about 20 mm to add this volumeof water to the stream system Once charged and the source terminated, drowdown would takeplace over at least several hours in an exponential fashion due to the declining grovity Row dischargerote in a weir system as the driving force of incremental head diminished.

Salmon Creek April 2013 Ba•• Flow EsUmation• Salmon Creek has a channel grodient of about 20'/4500' near Watson School per the USGS 7 5-min

quad map Valley Ford. Channel invert width varies, and appears to be about 18-20' in the vICinity ofthe lateral tributary. Using the April 11 flow ratio of 6.5 between Salmon Creek and the unnamedtributary based on NTU dilution Implies the Salmon Creek base now on Apnl11 was about 570 gpm x6.5 = 3700 gpm.

Salmon Creek Pumped Flow Impacts• Manning's equation using n=.05O for an 18' wide channel results in an average flow depth of about

5". Adding!l 12M gpm incremental flow to the base flow results in Q=4900 gpm and a flow depth of5.92" The average incremental depth associated with pumping is therefore less than an Inch.

• SF indicates the Salmon Creek channel distance between Watson School and the bridge on SalmonCreek Road is about 2 2 miles In order to provide 0.92" surcharge in that distance a water volume of2.2'5280'20' 92,12 =17,810 ft"3 is required, about 133,230 gallons. At 1200 gpm, it would require110 min. or aboul2 hours to prOVide the surcharge volume, With a wetted front moving downstreamat about 1.1 mph. Once chorged and the source terminated, drowdown would take place overseveral hours to tens of hours in an exponential fashion due 10the declining gravity flow dischargerate in a weir system as the driving force of incremental head dimiOlshed.

PAGE 12

Kistler Vineyards,14701 Bodega Highway, Sebastopol CA 95472Reservoir Drawdown EvaluatiOn on Unnamed Tributary and Salmon CreekErickson Engineering Inc. Volley Ford CA 94972-0446

Page 4.

January 19,2014

• The observations above do not support the contention made in the last paragraph on Page 25 that"the rapid rise and fall of Salmon Creek ... may have led to an increase in stranding of salmonidjuveniles and subsequently mortality as water levels dropped quickly:

Apparent IHue.ln the CAL EMA Spill NotifIcation 13·2166 Report• NTU Samples taken 4nO/"13 seem questiOnable. How can the umamed tributary value of 2140 NTU

exceed that of the source (Kistler small pond U56 NTU; ratio = 170%) taken a day apart and over amile downstream?

• PortiOns of the April ·10Goldridge RCD turbidity data are questionable. The Salmon Creek toUnnamed Tributary dilution ratio is best estimated at 6.5:1 per discussion above. The second andthird entries in Table 2 for trib and main stem both show NTU>·IOOO,implying the Salmon Creeksample was taken too close to the mouth of the Unnamed Tributary to obtain true dUution. Also,there are two entries for Unnamed tributary at 12:12 and U:20 with NTUs at 117and over 1000. Alethese the some points?

• The dote of Monday April 9 is used on Page 8 of the report when discussing Mr Molinar's pumpplanning schedule and start time. Monday was on April 8. The report apparently mixes planning andprocurement dates with starting and operating dates.

V.riance from CAL EMA Spill NotificatIon 13·2166 Report• The assessment above differs from that of Feiler as follows:

• 668,600 gal net diSChargeversus 1,000,000 - ·1,221,942 gal (55-157%of SF estimate)• ·148,000gal initial water credit for low turbidity• 1200 gpm versus 1300 gpm (94% of SF estimate)• 12 hr operation vs ·14-·15hours per Molinar/SF• Computations show rapid drawdown is not possible in the channel reaches affected.

TurbIdIty Data AssessmentThe 4/11113 NTU samples by S Feiler appear to have the best provenance and 10 be most consistent interms of numerical expectations between stations.

We have not researched the relationship between turbidity NTU and sediment transport. We expect thatit is a complicated subject based on many factors. In some cases turbidity can also be caused bymicroorganisms and organic motter, and would therefore not be well correlated or correlated at all withsediment transport. Should you wish to further investigate this tangent, it may be useful to contacthydrogeomorphologist Matt O'Connor PhD of O'Connor Environmental Inc. in Healdsburg who wouldperhaps have expertise in this arena.

Total Flows relative to In-Channel VolumeThe 2.2-mile reach of Salmon Creek between Watson School and the Salmon Creek Road bridge had anestimated base flow of 3700 gpm. Manning's equation computations wilh appropriate parameter valueswere used to show that the average flow depth in on 18' wide channel was 5.0' at on overage velocity of·1.08fps. Water stored in the channel reach amounts to 2.2 mi x 5280 fIImi x 18' x 5/"12'=> 87120 ftA3 or65·',660 gal. This may be compared to the pump rate of 1200 gpm and to the total pumped volumes.

PAGE 13

Kistler Vineyards, '14701 BOdega Highway, Sebastopol CA 95472Reservoir Drawdown Evaluation on Unnamed Tributary and Salmon CreekErickson Engineering Inc. Volley Ford CA 94972.0446

Page 5.

January 19,2014

Very truly yours,

Lee Erickson, PhO CE45660 AE468Civil and Agricultural Engineer

Attachments'1. Lorge Pond Plan and Profiles2. Large Pond storage calibration curve3. Stockpond Pion and Profiles4. stockpond storage calibration curve5. Wacker PT6L T pump drawing, pump curve6. Channel flow proportions based on NTU dilution ratios7. Manning's Equation for Unnamed Tributary with and without pumped flows8. Manning's Equation for Salmon Creek with and without pumped flows.

PAGE 14