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20070404 FEMA Info 08042009APPENDIX A-3 - VICINIW MAP ¡* ãâ ã ã a Ë ¿ã ıaÍ t Ë á E d åI s .ât2tãJÉ'8tôtú¡êE¡ ãã e'É tt PROJECT sTATt HWY 507 SE/SR 507 PALOUSE AVT. $I. Jnen ,,€crññ oro¡m,LARRJEWELL,^.ffi: SCALE: N/A V¡CINIWMAP EXHIBIT No: I OATE; ocT,2008 SHEET No: 1CHRISTENSEN COMMERCIAL APPENDIX A-4 - FEMA MAP I I I -,lzoNEAE IËxl LJ zo ZONE ZONE I vt APPROXIMATE SCALE IN FEET 50O O 50O mil0xft rr00D ttsürltct Pt0Sttt rt000 ttsuntilct Rtn mP CITY OF YELM, WASHINGTON (rr{uRsroN cor.rNTÐ OI{LY PAIIEL PNNTED cotmlilTï.PrrEr tutBER 53ß10 0001 A EFFECTIVE DATE: Fcrlcrat E¡uergency MülgÊm€ilt Agancy m extÉcted ß¡ng F-MÍT OÞUne. Th¡s map does not reÍect changes or amendments which may halê been made subsequent to the dãte on the t¡tle dæk. For the latæt product ¡nbrmation ãbout Net¡ond Flood lßuÞrce Program lood maps check the FEMA Flood MaÞ Store at w. APPENDIX A-5 - SOILS REPORT 158 SpanawaY Series The Spanaway series consists of very Ceep, somewhat excessively drained soils on terraces. These soils lormed in glacial outwash and volcanic ash. Slope is 0 to 15 percent. Elevation is 100 to 400 feet. The average annual precipitation is 40 to 55 inches, the average annual air temperature is about 51 degrees F, and ihe average frosl-free season is 150 to 200 days. These soils are sandy-skeleial. mixeC. mesic Andic XerumbrePts. Typical pedon of Spanaway gravelly sandy loam, 0 to 3 percent slopes, 4 miies souiheast of Lacey; about 250 leet west and 400 feet souìh of the northeasl corner of sec. 25. T. 36 N.. R. 1 'ú/. ,A-0 ìo 15 rnches: black (1OYR 2i1) qravelly sandy loam. very dark grayish brown (10YR 3'12) dr¡i: weak fine granular structure: loose, very friable, nonsticky anC nonplasiic: many fine, medium, and coarse roots: 25 percenl pebbles, slrongiy ac¡d: clea; srnooth boundary. 3w-15 to 20 inches; dark yellowish brown (1OYR 3i4) very gravelly sancly loam. llghi oiive brown (2.5Y 5ia) dry: weak line subangular blocky structure; loose, veiy friable, nonsticky and nonplaslic; many fine. rnediurn, and coarse roots. 55 perceni pebbles; rnediurn acid: clear smoolh boundary C-20 to 60 inches; dark yellowish b¡cwn (10YR 4i4) extremely gravefly sand, yetlowish brown (10YÊ 5i4) dry; single grained; loose; Íew frne roots; 80 percenl pebbles, 1O percent cobbles; slighily acid. The thickness of the solum ranges írotn i 5 io 25 inches. The content oi coarse fragrnents in the control secl¡on rangss from 50 10 85 percent. The weighted everage texture oT thìs section is very gravelly sand or extremely gravelly sand. The umbric apipedon is 10 to 20 inches thick. The A horizon has hue of 1OYR or 7.5Y8, value of 3 or 4 when dry. and chroma oí 1 o;'2 when moísl or dry. It is mediurn acid or strongly acìd. The Bw horizon has value of 4 or 5 when dry and 3 or 4 when moist. lt is very gravelly sandy loarn, very gravelly loam, or extremely gravelly sandy loam. The C horizon has hue ol 1OYR or 2.5Y. value of 5 or 6 when dry and 4 or 5 when moist. and chroma of 3 or 4 when dry or moist. lt is extremely gravelly sand or extremely gravelly loamy sand and is slightly acid or neutral. Sultan Series The Sultan series consrsls of very deep, moderateiy Soil Surve, wetl drained soils on flood plains. These soils lormed alluvium. Sfope is 0 to 3 tercenl. Elevation is ZO to-],feet. The average annual precipitation is 4O to S0 inclres, lhe average annual air iemperature is about Edegrees F, and the average frosl-free season is 1;ò I200 days. These soils are fine-silty. mixed, nonacid, mesic Aqurc Xerofluvents. Typical pedon of Sultan silt toarn, 7 rniles east of Lacey; about 1,000 feet east and 1,975 feet north of : southwesi cornêr of sec. 16, T. 1E N,, R. 1 E, Ap--o to 7 inches; dark yellowish brown (1oYR 3/a) s loam. brown (10YÊ 5/3) dry: rnoderate fine and medium' granular structure; slightly hard. very friable. slightly s'ricky and stightÍy plastic; rnany Íir rneCium, anci coa¡se roots; many very fine and fir tubular pores; slightly acici: abrupt smooth boundary. 3A-7 to 20 ìnches; dark yellowish brown (1OYF 4j4) silì lcam, brown {1OYR 5/3) ciry: moderate fine an meCium subanEular blocky structure; slightty hard very friable, slightly sticky and slightly plastic; r¡a vei'y fine, fine, and medium rcots; many very fine and fine tubular pores; slightly acid; clear wavy boundary. 3w1-20 to 25 inches; dark brown (10Y4 3/3) silt loa grayish brown (2.5Y 5i2) ciry; common fine prominent red (2.5YF 5/8) motttes: mcderale íine and medium subangular blocky slructure; slightly hard, very friable, slightly stictry and slightly plasti common fine and medium roots: common very iin and fine tubular pores: slightly aciC: graduaìrvavy boundary. 8rv2-25 to 45 inches; dark brown (1OYR 4/3) silt lca light brownish gray (1OYR 6i2) dry: common meciium prorninent red (2.5YF 5i8)'moiiles; moderate medium and coarse subangular blocky structure: slightly hard, very fnable, slightly sticky and slightfy plastic: few very fine and line roots;fr very Íine and fine iubular pores; slìghtty acid; Eradual wavy boundarY. C-45 to 60 inches; grayish brown (1OYR 5/2) silt loa light gray (1OYR 7!2) dry: cornrnon medium piominent dark brown {7.5YR 4i4) mottles: massi' slightly hard, very friable. slightly stícky and stighl plastic; slightly acid. The soils are slighfly acid or neutral in the control section and range irom slightly acid lo strongly acid - beloru a depth ot +o ¡ncheı. ¡vottles that have chrorn¿ oí 3 or more are at a depth of more than 20 inches' i: È \1 t - . Thurston County, Washinoton . summer, irrigalion is needed for lawn grasses, shrubs, vines, shade trees, and ornamental trees. Mulch, ' fertilizer, and irrigalìon are needed to establish lawn grasses and other srnall'seeded plants, Topsoil can be slockpiled and used to recla¡m areas disturbed during' construction. The main limitat¡on aríecting septic tank absorption .fields is a poor filterìng capacity in the substratum. lf the densiiy of housing is moderate or high, cornmunity sewage systems are needed to prevent the contamination of water supplies caused by seepage from onsite sewage disposal syslems. The slope hinders the insiallation of the absorption fields. ....Absorptìon lines shoulC be ¡nstalled on the contour. Ðouglas-fir is the main woodland species on this unil. Among the lrees of límited extent are Oregon white oak, lcCgapole pine anC red alder. Douglas.fir anC Scolch pine are grown on Chrisimas tree plantations. On the basis of a 100-year site curve, the mean site index for- -Dougfas-iils 140. On ttie basis of a SO-year siie curve, it is 1 08. The highest average growth rate of an un,'nanaged, even-ageC stand oi Douglas-fir is 145 cubic feet per acre per yeeí at 65 years of age. This soil is suited to yeâr-round logging. Unsurfaced roads and skrd trails are slrppery when wet Logging rcaCs require suitable suríacing material lor year-round use. Êounded pebbles and cobblas for road constructron are readilr¡ available on this un¡t. Ðistur5ance oí ihe proleclrve layer ol dui can be minrr¡izeC by ihe careful use of wheeled and tracked equipment, Seedlrng establishrn-.nt and seedling rnorlality are .rhe rnain concerns in the production of limber. Reforestation can be acconrplished by pfanting Dougtas-fir seedlings. lf the stand includes segd trees, natural reforestation of cutover araas by Oregon white oak and lodgepofe pine occurs inirequenily. Droughtiness in the surface layer reduces the seedling survival rate. When openings are made in the canopy, invading brushy plants can delay the establishment oi planted Douglas-fir seedlings. Common forest understory plants are cascade Oregon-grape, salal, western brackenfern, western swordlern, lndian plum, and Scotch-broom. This map unit is in capabifity subclass lVs. 112-Spanaway stony sandy loam,0 to 3 percent slopes. This very deep. somewhat excessively drained soìl is on terraces. lt forrned in glacial outwash and volcanic ash. The native vegetation is mainly grasses, ferns, and a few conifers. Elevation is 200 to 400 feet. The average annual precipitation is 40 to 50 inches, the average annual air temperature is aboul 5t degrees F, and the average frost-free perioci is l S0 to 200 days. Typìcafty, the surÍace fayer is btack stony sandy loaboul 16 inches thick. The subsoil is very dark brıwngravelly sandy loam about 6 inches thick. The substratum to a depth of 60 inches or more is grayist brown extremefy gravelly sand. lncluded in this unit are small areas of Alderwood soils on till plains, Baldhill soils on lerminal moraínes, and Evereit. lndianola, and Nisqually soils on terrace: Also included are small areas of Spanaway soits that have a gravelly sandy loam surface layer and small areas of Spanaway stony sandy loam that have slope oÍ 3 to 15 percenl. lncluded areas make up about 1 S percent of the total acíeage. Permeability rs moderately rapid in the subsoil of tt Spanaway soil and very rapiC in the substratum. Available rvater capacity is fov,r. Effective rooting depi; is 60 inches or more. Runofi is slor,,,, and the hazard r water erosion is slight. This unit is used mainly lor hayland, pasture, or hornesites. The main limitations affecting hay and pesture are the low avaifable waler capacity and ìhe stones on the sudace. Proper grazing practices, weec control, and íefilizer are naeCeC to ensure maximum quafity of forage. Rotaiion grazing helos to maintain tl Quêlity oi tha forage. Because of the surfac? Stones, spreadrng animaf rnanure, mowing, and seeding are difficult. ln summer. irriqation is needed for rnaxìmum production of most forage crops. Sprinkler irrigalion is the best method oÍ applying rvater. The amouni of war apclied should be sufticient to vyet the root zone buî small enough to minimize the leaching of plant nuirientS. Thrs unit is well suited to homesítes. Pebbles, ccbbles, and stones should be removed, pafticufarly ír areas used for lawns. In sumrner, irrigation is needed íor lawn grasses, shrubs, vines, shade lrees, and ornamental lrees. Mulch, fertilizer, and irrigation are needad to establish lawn grasses and olher smalf- seeded plants. Cutbanks are not stable and are suble( to sloughing. The main lirnitation aftecting septic tank absorption fìelds is a poor filtering capacity in the substratum. lf tl density ol housing is rnoderate or high, ccmmunity sev/age systems are needed to preveni the contamination of water supplies caused by seepage from onsite sewage disposal systems. Ïhis map unit is in capabilily subelass lVs. '113-Spanaway stony sandy loam, 3 to 15 percer slopes. This very deep, somewhat excessively drainec soii is on terraces. lt formed in glacial outwash and tilrffiñfi Jerome W. Morrissette & Associates lnc., P-S. 1700 Cooper Point Road SW, #B-2, Olyrnpia, WA 98502 (360)3s2-94s6 i FAX (360)352 Evaluation Conducted Project En ineer: l, Method of Excavation:r,¿ : 6t4ûþ ¡J L1{ Soil Eoring Log I È.i ãL .a Project Name: RtcK L'j€:.-rt;it 1ag.ç.1 tbtlflg tlr¿'i å)Ï ì V'å t-/L ú, +ìo Soil Description t"'r,=9-:d-Å.fi:- ¡-'r.:?'ì íteerfl, r;- 1i¿.11 Project Nu.rnben tS l{, Boring NumberN Date: Gontractori a,¡¡ r.i í fi Totat DePth of Hole: COLOR Ë Í?o/'-!. U¡q.;:--t {t *\€a ¡ (..+\ .*P i ÊÈ- t'trj .- ..-.-. .-¡i- i-.'.- .---- . -¡- .¡-fuVg;r;ar -':Fæ-t'<r'TË ij lltvDlñ^t Jerorne W. Morrlssette & Associates lnc., p.S. 1700 Cooper Point Road SW,_tï?, gtYmpia, WA S9502_1110(3ô0)352_9456 / FAX {360)352_9990 Soil Boring Log Project Number:PrOject Name: ?li._li riill.r ¡. : c,.1"p,.r. .c.¡¡ J LOcatiOn: ì&ü-¿fl *rJr {,r", yÉL; Total Depth of Hole: Evafuation Conducted ineer: -i- Method of Ëxcavation:n*ï T.¡lì É^ìåqj_ Soil DescrÍption :< r1;'a-'. çÇ i" f .- 1i iìÍ .'1;.' l- Civil / Municipal -/ .Geolechnicat Engineenng and ptanning l l I *7, i_ fJ -ì\ ) 'îF !atsn ¡I t. t" fr"' ¡ t i_ II t tII -....- r- -- I : I : I u .t SOIL EVALUATION REPORT FORIVI 1: GENERAL SITE INFORMATION PROJECT TITLE: n¡.X Ctr¡",¡"*è PROJECT NO.: DATE:3/ZS,.3 PREPARED BY: John Knowles, P.E. 'ñ LE\rrlL r,rtrù\,¡il1- r ruN: Nonn of uKþu/, rmmed¡ately west of the yelm Creek crossing (11628 SR 507, Yelm, WA) 3. SITE DESCRIPTION: The rectangular shapéd projec residentialbuilding (to be removed) centÍally located on the southern ìrc otine site. Site relief isrelalively flat with the excoption of the eastern 1/4 of the site that slopes to lhe east at a So/ogradient. Ïhe extreme eastern portion of the site is a designated weiland bordering yetrn Creek. The site has relalively few trees and a light density of Scoi's Broorn growth througÉout the site. The project site ís bounded by undeveloped prôperty to the north anã east, a Chevron Mini Mart tothe west, and SR507 to the south. On site soils are well drained and formed in glacial outwash. 4. SUMMARY oF solLs WORK PERFORMËD: Five test pits were excavated by bãıÈhoe t,c amaximum deplh of 120" below exísting grade. Soils were inspected by entering aÁd visually logging each test pit to a depth of four feet. Soils beyond four feet weie inspected by examining backhoe tailings, Test pit soil fog data sheets are included in this report. 5. ADDITIONAL SOILS WORK RECOMMENDED: Additlònal soits worf witt tit<ety Ue requirø once a site plan has been generated and lhe location of proposed drainage infittrãtion facìliües are identified. 6. FINDINGS: The Soil Conservation Serviðe o Spanaway Stony Sandy Loam (112). All test pits confirm this designat¡on. Rtt test pits revealed verygravelly fine sandy loam surface soils, overlying a gravelly and càbbley coarse sand subslratum. Substratum coarse soíls were loose to slightly dense and had very few fìnes present. Winter water table was present in all test pits and should be considered high for the season. 7. RECOMMENDATIONS: The Spanaway soiiier¡e formed ín glacialoutwash. lnfiltration rates are:generally rapid in the substratum soils. The substratum soils should be targeted for alldrainage infiltration facilities. A design infìltration rate of 20 inihr would be appropriate for all targeted C horizon soils as recomrnended in the attached soil log information sheels. During construction, care must be taken to prevent erosion of exposed soils. Drainage facility infiltration surfaces must be properly protected from contamination by the fine-graineã upper horizon soils and from compaction by site construction activities. Soils not properly protected will cause drainage infiltration facilities to prematurely fait. I hereby certify that I prepared this report, anO Con¿ucted ıi-gupen work. I certífy that I am qualified to do this work. I represent my vr within the bounds of uncertainty inherenl to the practice of soils s< intended use. SIGNED: DATE. î g rísed the performance of related 'ork to be complete an accurate :ience. and to be suitable for its t4:öffi* t\, lc:tWINWORDIJEKFILES\0 3l 4soUs ipl) $[ro,ver- tsÌd ÊxF'rn€s. //,/la /2oe I F[Aj EEi ilJ:'¿fiT- christi anen Retaii - PREPARED BY: John Knowles. P.Ë. SOIL LOG: Fl LOCATION: 30 ft. east and 20 ft, south of the N.W. property cornêr. 1, TYPES OFTESTDONE; None 2. SCS SOILS SÊRIES: Spanaway Stony Sandy Loam (112\ 3, I-AND FORM: Terrace 4. DEPOSITION HISTORY: Glacial outwash & volcanic ash 5. HYDROLOGIC SOIL. GROUP: B 6, OEPTH OF SEASONAL HW: 116"+ 7. CURRENTWATER DEPTH: 1 16" 8. DEPTH TO IMPERVIOUS LAYER: Greater than bottom of hole 9. MISCELI.ANEOUS: Level 10. POTENTIAL FOR:EROSION I RUNOFF I PONDING Slight Slow I Minimal 11. SOIL STRAïA DESCRIPTTON: See Foilowing chart 12. SITE PERCOLATION RATE:See FSP 13. FINDINGS & RECOMMENDATION infiltration facilities located in the C2 horizon soils'at 30" or greater below the existing ground surfãce.Maintain minimum separation requirements above the high winter water table obseÑed at BB" + below lhe existing grade. SOIL EVALUATION REPORT FORM 2: SOIL LoG INFORMATION $oils Strata Description Soil Log #1 Hotz A Bw c1 c2 Deoth 0'- 22" 22". 25' ?s',: 30' 301t00' Color Tgxlursi 10YRZ2 VGTVFiSaLm 10YR3/2 VGfVF¡SaLm 10YR4/6 ExGr & CobLmMSa 10YR5/4 ExGr & CobCSa %cL g/ooRc <20 <5 <20 <5 <5 STR MqT 1S8K lSBK SG ¡tJ CEM ROO -mf -ml 'îl <X> FSF 2-6 2 2-6 3 >20 15 CF <50 <60 <75 <90 IND >20 SOIL EVALUATION REPORT FORM 2: SOIL LOG INFORMATION PROJECT TITLE: Rick Christianen Retail PROJECT NO.: 0314 PREPARED BY: John Knowles, P.Ë. SHEET: 2 OF 5 DAïE:3/25/03 SOIL LOG: #2 LOCATTON: 400 ft. east and 20 ft. south of the N.W. property corner. 1. TYPESOFTÊSTDONE: None 2. SCS SOILS SERIES: Spanaway Stony Sandy Loam (1 12) 3. LAND FORM: Terrace 4. OEPOSITION HISTORY: Glacialoutwash & volcanic ash 5. HYDROLOGIC SOIL GROUP: B 6. DEPTH OFSEASONAL HW: 88" + 7. CURRENTWATER DEPTH: 88', 8. DEPTH TO IMPERVIOUS ISYER: Greater than bottom of hole 9. MISCELLANEOUS: Level 10. POTENTIAL FOR:EROSION I RUNOFF I PONDING Slow I MinirnatSlight 11. SOf L STRATA DESCRIPTION: See Following charl 12. SITE PERCOLATION RATE:See FSP l3jlfrlDlNGS & RgCOUtUgfVOATIONS: Úse a design infìltration rate of 20 inihr for drainage infiltration facilities located in the C2 horizon so¡ls at 30'or greater below the existing ground surface. Maintain minimum separation requirements above the htgh winter water table observed at 88" + below the existing grade. Soils Strata Description Soil Log #2 Hoq Deolh Cotor Texturq ZLçL ygO-RG. CF. gTB ÙlOT INO CEM ROO <Xì FSP A 0'! 18" 10YRZ2 VGTVFiSaLm <20 <5 <50 lSgK ' mf 2'6 2 8w 18'- 21" 1OYR3/2 VGTVFiSaLm <20 <60 1SSK ' mf 2'6 3 Cl 211 30" 1OYR4/6 ExGr & <5 - <75 SG fi >20 15 CobLrnMSã C2 30':100" 10YR5/4 ËxGr & <5 - <90 SG >2o 20 CoþCSa PROJECT NO.; 0314 PREPARËD BY: John Knowtes, p.E.DATE:3/ZSl03 LocATloN:210 ft. east and 20 ft. south of the N.w. properry corner.1, TYPES CIF TEST 2. SCS SOTLS SERTES: Spanaway Stony Sandy Loam (112) 3. LANO FOR¡/|: 4. DEPOSITION HISTORY: Glacial outwash & volcanic ash 5. HYOROLOGIC S GROUP: B 6. DEPTH OFSEASONAL HW: 7. CURRENTWATE DEPÏH: 91' LAYËR: Greater than bottom of hole 9. MISCELLANE 10. POTENTIAL FOR: PTION: See Foltowing chart 12. SITE PERCOLA See ,'"1,,, ll ?ll9^s.1-TF g Pylv' E facililies located ¡n the c2 horizon soils at 32" or greater below the existing ground surface. Maintainrninimum separation requirements above the high winter water table observed at g1. t below theexisting grade. SOIL EVALUATION REPORT FORM 2: SotL Loc INFORMAT|ON Soils Strata Description Soil Log #3 Horz 9w c1 Deoù f- 20" 20'. 23" 23'- 32', 321100" Color Te)dure %C[ %ORG IjYRUZ VGrVFíSaLm <20 <s l0YR3/2 VGrVF¡SaLm <ZO t0YR4/6 ExGr & <s CoþLmMSa 10YR5/4 ExGr & <5 CobCSa CF <50 <60 <75 <90 srR MOJ 1s8K lSBK SG SG CEM ROO -ml -mf 'ff <X> FSF 2.s 2 2.6 3 >20 1: IND PROJËCT TITLE: Rick Christianen Retail PROJECT NO.:0314 PREPARED BY: John Knowles, P.E. SHEET:4 OF 5 DATE: 3125103 SOIL LOG: ll4 LOCATION: 100 ft. east and 200 fL south of the N.W. property corner. 1. TYPES OF TEST DONE: None 2. SCS SOILS SERIES: Spanaway Stony Sandy Loam (112) 3. LAND FORM: Terrace 4. DÊPOSITION HISTORY: Glacialoutwash & voleanic ash 5. HYDROLOGIC SOIL GROUP: B 6. DEPTH OF SEASONAL HW: 106" + 7. CURRENT WATER DEPTH: 1 06" 8, DEPTH TO IMPERVIOUS LAYER: Greater than bottom of hole 9. MISCELLANEOUS: Level 10. POTENTIAL FOR:EROSTON I RUNOFF I PONDTNG Slight lSlowlMinímal 11. SOIL STRATA DESCRIPTION: See Follöwing chart 12. SITE PERCOLATION RATE:See FSP 13. FINDINGS & RECOMMENDATIONS: Use a design infiltration rate of 20 in/hr for drainage infillratìon facilities located in the C2 horizon soils at 31" or greêter below the existing ground surface. Maintain minimum separation requirements above the high winter water table observed at 106" 1 below the existing grade. SO¡L EVALUATION REPORT FORM 2: SolL LoG INFORMATION Soils Strata Description Soil Log #4 Hor¿ A Bw c1 C2 Deoth 01 20' 20'- 23 231 31' 311120" Color T.exture r0YRZ2 VGTVFiSaLm 1OYR3i2 VGrVFìSaLm 10YR4/6 ExGr & CobLmMSa 10YR5/4 ExGr & CobCSa %CL %ORG <20 <5 <20 <5 <5 CF <50 <60 <75 <90 sr8 Mgr 1 SBK I SBK SG SG CEM ROO -ml - ¡1|, -rl -<.{'- FSP 2.6 2 2-6 3 >?0 15 >20 IND HcE A Bw c1 t^a Deolh Color 0". 10YR2t2 20" 20'. 10YR3i2 22" 22'. 10YR4/6 28' 2E'. 10YR5/4 I t0' ïextu¡e ToCL VG¡VFíSaLm <20 VG¡VFiSaLm <20 ExGr & <5 CobLrnMSa ExGr& <5 CobCSa cEM ROq -mf -mf .ff *, FSP 2.6 2 2.6 3 >20 15 >20 20 SOIL EVALUATION REPORT FORM 2: SO|L LOc |NFORMAT|ON Soils Strata Description Soil Log #5 %oRG cF SIg <5 <50 1s8K - <60 1SBK - <75 sG - <90 sG MOT tNo CT TTTLE: Rick CrrrisriããıFãiãä PROJECT NO.:0314 PREPARED BY: John Knowtes, p.E. SOIL LOG: #5 LOCAT'ON:.250 ft. wesr and 50 ft.¡orth of the s.E. proporty cofner. 1. WPES OF TEST DONE:2. SCS SOrLsEiES Spanaway Stony Sandy Loam (112) 4, DEPOSITION HISTORY: Glacial outwash & volcanic ash 5, HYDROLOGIC SOIL GROUP: B 6. DEPTH OF SEASONAMWJ 7, CURRENTWATER DEPTH: 90" 8. DEPTH TO IMPERVIÓUS LAYER: Greater than bottom of hole 10. POTENTIAL FOR: IPTION: See Fottowingr.trart PERCOLATION RAÍE: sgq il rilru Ifacilities located in the c2 horizon soils at 28" or greatãr berow the existing ground surface. Maintainminimurn separation requirements above the high winter *ate, iaotå observed at 90,,+ below theexist¡ng grade. Abbreviations Textural Class (Texture) Structure (srR)Grades of StruEure Cobblev -Cob Granular . Gr Strong - 3Stonev - St Blocky - Btky Moderate - 2Gravellv - Gr Platy -Pt Weak - 1Sandy - Sa Massive - MasLoamv - Lm Single Grained - SGSilty - S¡Sub-Angular Blockv - SBKClayey - Cl Goarse - CVery -V Extremelv - ExFine - F Medium - M lnduration & Gementation(t¡!_p_l (cEM)Weak - Wk Moderate - Mod Strong ,,- Str Mqttlæ (MoT) 1 Letter Abundance lst Number Size 2nd Letter ContrastFew -F Fine - 1 Faint - FComrnon - C Medium - 2 Distinct - DMany - M Coarse - 3 Prominent - P Roots (ROO) 1st Letter Abundance 2nd Letter Size Few -f Fine - fCommon - c Medium - mMany - m Coarse - c APPENDIX A.6 - AQUA-SWIRL DATA AquaShieldg STORM\A,/ATER TF'EATME N'T SOLUTIc)Ns' q U a - 5W I f l rroRMWArER TREATMENT sysr. lns & Maintenance o AguaShreldrM offers an extensive maintenance program that ensures sysúern performance efficiencY o Download manuals from the on-line system catalog Outlet Vortex Separation o Utilizes hydrodynamic and gravitational forces with quiescent settling to remove gross pollutants o Extensive Computational Fluid Dynamic (CFD) modeling and full-scale physical testing by independent third parties lnstallation Benefits ¡ Quick and simple installation, resulting in measurable projecf cosf savings c H20 loading capabílities o Small footprint desþn reduces excavation cosfs o Lightweight and durable construction o Liftíng supporfs & caþfes provided Ê o Sysúems are designed to treat water quality flow rates and bypass peak storm eyenfs c lnternal and external bypass configurations are available o Sysfems are designed with custom inlet / outlet diameters at various configuration angles o lnlet/ outlet sfuþoufs are provided for easy coupling Capacities o Large sforage capacities for oil, debrís, and sediment extend maintena nce cycles o Sedimenf sforage capacifies range up to 270 ft3 o Oil and debris sforage o Provides customized solutíons for proiect specific requirements o Systems designed for specific water q u a I íty treatm e nt fl ows o Modular szes from 2.5 - 12 ft diameters with attached risers to linish grade c On-lÍne proiect and sysfem design tool at http : // p d a. aq u a sh í eld i nc. com (r Inlet Aqu ashield@* STOR M\A/AT ER TREAT MENT SOLUTI ONS capacities range up to 1688 gallons ua-SwirlrM g 3#fiilHlr.."atmenr I : l Introduction System Operation Retrofit Applications Installation * Buoyancy ,; Traffic Loading Inspection and Maintenance Aqua-Site Worksheet Aqua-Swirlil Sizing ChaÊ Aqua-Swirl rM Sample Detail Aqua-Swi rl rM Specifications ffi Aquash¡eldg- STE RMWATER TREATM ENT S tr LUTI trI N 5 Table of Contents AQUA-SWIRL" STORMWATER TREATM ENT SOLUTTONS System Operation Custom Applications Retrofit Applications Installation Buoyancy Traffic Loading Inspection and Maintenance Aqua-Site Worksheets Aqua-SwirlrM Sizing Chart (EnglÍsh) Aqua-Swirl'M Sizing Chart (Metric) Aqua-Swirl'" Sample Detail Drawings Aq ua-Swirlr" Specifications General Scope of Work Materials Performance Treatment of Chamber Construction INSTATTATTON Excavation and Bedding Backfill Requirements Pipe Couplings DIVISION OF RESPONSIBITITY Stormwater Treatment System Manufacturer Contractor SUBMITTALS QUALIW CONTROL TNSPECTTON 2 2 4 4 5 5 6 6 7I 9 13 15 15 15 15 16 16 L7 L7 1B 1B 18 18 18 19 19 2733 Kanasita Drive, Suite B r Chattanooga, Tennessee37343 Phone (888) 344-9044 o Fax (423) 826-2L12 www.aquashieldinc.com -)l/::¡ ([ =z Aqua-Swirl" Stormwater Treatment SYstem The patented Aq ua'Swirl " Stormwater Treatment System provides a highly effective means for the removal of sediment, floating debris, and free oil. Swirl technology, or vortex separation, is a proven form of treatment utilized in the stormwater industry to accelerate gravitational separation. Independent university laboratory performance evaluations have shown the Aqua-SwirlrM achieves a TSS (Total Suspended Solids) removal of 91o/o calculated on a net annual basis. See the "Petformance and Testing" Section for more details, Each Aqua-Swirl" is constructed of lightweight and durable materials, eliminating the need for heavy lifting equipment during installation. Inspection and maintenance are made easy, with oversized risers that allow for both examination and cleanout without entering the chamber. g sYstem operation The Aqua-Swirl", with a conveyance flow diversion system, provides full treatment for the most contaminated "first flush", while the cleaner peak storm flow is diverted and channeled through the main conveyance pipe. Many regulatory agencies are in the process of establishing "water quality treatment flow rates" for specific areas based on the initial migration of pollutants into the storm drainage system. The treatment operation begins when stormwater enters the Aqua-Swirl" through a tangential inlet pipe that produces a circular (or voftex)flow pattern that causes contaminates to settle to the base of the unit. Since stormwater flow is intermittentby nature, the Aqua-Swirl" retains water between storm events providing both "dynamic and quiescent" settling of solids. The dynamic settling occurs during each storm event while the quiescent settling takes place between successive storms. A combination of gravitational and hydrodynamic drag forces encourages the solids to drop out of the flow and migrate to the center of the chamber where velocities are the lowest, as shown from extensive CFD modeling. See "Performance and Testing" for more details. A large percentage of settleable solids in stormwater are reported tohave low velocities. Therefore, the volumeof water retained in et ¡5r-.È*n+tr In let Floatable debris in the Aqua-Swirl'" be small and settling f Outl the Aqua-Swirl" provides the quiescent settlingthat increases performance. Furthermore, due to finer sediment adhering onto largerpafticles (less than 200 microns), the larger pafticles settle, rather than staying suspended in the water. The treated flow then exits the Aqua-Swirl'* behind the arched outer baffle. The top of the baffle is sealed across the treatment channel, thereby eliminating floatable pollutants from escaping the system. A vent pipe is extended up the riser to expose the backside of the baffle to atmospheric conditions, preventing a siphon from forming at the bottom of the baffle. As recommended by the Center for Watershed Protection and several municipalities, the Aqua-SwirlrM can also operate in an offline configuration providing full treatment of the "first flush." However, this orientation requires the installation of additional manhole structures to diverge the flow to the Aqua- Swirltr¡ for treatment and conveyance back to the existing main conveyance storm drainage system. Custom Applicationsrcr-7 Custom designed AS-9 Twin, Aqua-Swirlr" products to adapt to a variety of applications. The Aqua-Swirl" system can be modified to fit a variety of purposes in the field, and the angles for inlet and outlet lines can be modified to f¡t most applications. The photo on the left demonstrates the flexibilityof Aqua-Swirl" installations. Two Aqua-Swirl" units were placed side by side in order to treat a high volume of water while occupying a small amount of space. This configuration is an example of the many ways AquaShield" can use our -1 rcr.Y Retrofit Applications The Aqua-Swirl'* system is designed so that it can easily be used for retrofit applications. With the inveft of the inlet and outlet pipe at the same elevation, the Aqua-Swirl" can easily be connected directly to the existing storm conveyance drainage system. Fufthermore, because of the lightweight nature and small footprint of the Aqua-Swirl", existing infrastructure utilities (i.e., wires, poles, trees) would be unaffected by installation. rcf-t7 Installation The Aqua-Swirl" system moving parts so that no installation of the system. is designed and fabricated as a modular unit with no assembly is required on site. This facilitates an easy Since all AquaShield'* systems are fabricated from high performance materials, the Aqua-Swirl" is lightweight, and can be installed without the use of heavy lifting equipment. Lifting supports or cablesare provided to allow easy offloading and installation with a trackhoe. Compared to concrete systems, using an Aqua-Swirl" can significantly reduce installation costs. In addition, manufactured stub-outs for the inlet and outlet are provided. This allows the contractor to simply attach the Aqua-Swirl" directly to the main conveyance storm pipe with rubber couplings. Typically, an AquaShield" representative is present on-site to assist in the installation process.a trackhoe Buoyancy All Aqua-Swirl" systems are supplied with an octagonal base plate that extends a minimum of 6 inches beyond the outside diameter of the swirl chamber. The function of the extension on this base plate is to provide additional surface area to counter any buoyant force exerted on the system. The forces created on the base plate by the weight of the surrounding fill material offsets the buoyant force generated within the system. If needed, concrete can be poured directly onto the base plate to provide additional resistive force. The AquaShield" engineering staff can provide buoyancy calculations for your site-specific conditions. The Aqua-Swirl'" installed using Traffic Loading When installed in traffic areas, the system will be designed to withstand H-20 loading. In order to accomplish this, a reinforced concrete pad shall be poured in place above the system. See the "Installation and FabricatÌon'sedion for sample concrete pad details and further details on installation, rc!Inspection and Maintenance Concrete pad protects the Aqua-Swirl'" from lmpact loading Sediment inspection using a stadia rod Inspection and cleanout of the Aqua-Swirl" is simple. The chamber can be inspected and maintained completely from the surface. Free-floating oil and floatable debris can be directly obserued and removed through the provided seruice access. Cleanout of accumulated solids is needed when the usable storage volume has been occupied. The depth of solids can easily be determined using a stadia rod or tape to measure the top of the solids pile and calculate the distance to the water's surface. A vacuum truck can be used to remove the accumulated sediment and debris. Disposal of the material is typically treated in the same manner as catch basin cleanouts. AquaShield" recommends that all materials removed be handled and disposed of in accordance with local and state requirements. For fufther details on inspedion and cleanout procedures, please see the "Maintenance" sedion.Vacuum truck cleans the Aqua-Swirl'" Í[Y Aqua-Site Worksheets Aqua-Site worksheets are provided as an example of the information that AquaShield" will need to customize an AquaSwirl* to a specific work site. t I completed examplec 2 blank worlcheeß 7 ågyg9.higlgg" ¡ij::. ir. lrìi,r, ; ìi AquaShieldtM, Inc. 2733 Kanasita Drive, Suite B o Chattanooga, TN 37343 Phone: (888) 344-9044 o f¿¡¡ (423) 826-2112 www.AquaShieldlnc.com Aqua-Site Worksheet Project Information Project Name: Ølnty Hqitd Specifier Information Desisner's Name: Shg,i fti ll i pS Location (C¡ty, state): AnyTAUn, U&Desisn F¡rm¡ Ffiili næflw S¡te Use (circle one): Site Plan Attached: Pollutänts (TSS, Floatable Debr¡s, olls/greâse, TP, etc,): Residentiat @ Industriat other Address: 123 Mdn Sreá I ves 7SS D#is ñ/'o c¡ty, ståte, zipt AnyTA¡ln, U & pnone'423ffT0ffi AutoCAD Versionl Date Subm¡ttedr 4,0 F"'' 42182G2112 912/m E-ma¡r : Stls'i @h7 I i psøgr.øn Specifications Un¡t Label or Manhole Numb€r AquaShieldrM Model Design Flow Rate ¡nlet/Outlet Pipe R¡m Elevation Dra¡nage Area lnfo Traff¡c Loeds Water Qual¡ty Treatment Flowl (ds . L/s) Peak Des¡gn Flow2 (cfs - r-ls) Size (ID) (in . mñ) Invert Elevat¡on llt-m) P¡pe Mater¡al Tyoe Finish Grade Elevat¡on (rt - m) Area (acres - hð) Incoming Slope ("t") Runoff Coeflìc¡ent c Est¡mated Groundwater Elevatron (fl - m) ls the system subject to H-20 load¡ngs? Yes or No A-1 AS6 5.3 15.9 1B 7æ.2 ROP 745.6 8,2 0.74 0.9 N/A Yes Special Site Conditions or Requirements: How did you learn about Aqua-ShieldrM z W&jte Please orovide copv of Site Plans showino orientation (t) wðter Quality Treatment Flow ¡s presr¡bed by local regulatory agenc¡es to achieve full treatment of spec¡fìc amount of stormwater. (2) Peak Des¡gn Flow refers to maximum calculated flow for an outfall or recurrence interual (1o-yr, 25-yr event) Specifier's Signature: Sá4r?¿ ?h/1¿þ4 Date: 12-Mar-04 AquaShieldg'" 5l (f RM\^/^TEl:¿ Tt?E¡l1 MEl.lT SCJLt Jl'lfJ NS ., '. ; ';,r.,: I r.i,lr: ; r:; AquaShieldtM, Inc. 2733 Kanasita Drive, Suite B o Chattanooga, TN 37343 Phone: (888) 344-9044 o Fax: (423)e26-2LL2 www.AquaShieldlnc.com Aqua-Site Worksheet Project Information Project Name: Specifier Information Location (City, State) : S¡te Use (circle one): Site Plan Attachedl Pollutânts (TSt Floatable Debr¡s, olls/grease, TP, etc.)¡ AutoCAD Versionr Date Submitted: Residential Commerical Industrial Other f ves Iro Des¡gner's Name: Design Firm: Address: C¡ty, State, Zip: Phone: E-mail: Specifications Unlt Lab€l or Manhole Number AquaShieldrM Model Design Flow Rate Inlet/Outlet P¡pe Rim Dralnage Area lnfo Traff¡c Loads Water Quality Treatment Flow! (cfs - t/s) Peak Desrgn Flovr¿ (cfs - L/s) Size (¡D) (rn - ñm) Invert Elevat¡on (ft-m) Pipe Material Tvæ Fin¡sh Grade Elevation (ft - m) Area (acres. ha) Incom¡n9 Slope ("/ù Runotf Coeff¡c¡ent c Est¡mated Groundwater Elevation (ft - m) Is the system subject to H-20 load¡ngs? Y6 or No Special Site Conditions or Requirements: How did you learn about Aqua-ShieldrM ? Please provide cooy of Site Plans showing orientatiotr (1) water Qual¡ty Treatment Flow is presribed by lo(ðl regulatory agencies to achieve full treatment of sæc¡fìc amount of stormwater. (2) Peak Design Flow refers to maximum calculated flow for an outfall or recurrence ¡nterual (10-yr, 25-yr event) Specifier's Signature:Date: Ag:¿g9.hlg!gH \' .. , ', ,,!l : l r ,, r ri AquaShieldrM, fnc. 2733 Kanasita Drive, Suite B o Chattanooga, TN 37343 Phone: (888) 344-9044 o f¿;¡ (423) 826-2112 www.AquaShieldlnc.com Aqua-Site Worksheet Project Information Project Namel Specifier Information Locat¡on (C¡ty, State): S¡te Use (circle one): S¡te Plan Attached: Pollutånts (TSS¡ Floatable Debrls, o¡ls/gre¿se, TP, etc.): Residential Commerical fl vrs Industrial Other [*o Designer's Namel Design Firm: Address: C¡ty, State, Zip: Phone: AutoCAD Version: Date Subm¡tted! Fax: E-mail¡ Specifications Unit Label or Manhole Number AquaShieldrM Model Design Flow Rate lnlet/Outlet P¡pe R¡m Elevation Dra¡nage Area lnfo Traf¡c Loads Water Quality Treatment Flowl (cfs - L/s) Peak Desrgn Flowz (cfs . L/s) Size (ID) (¡n . mm) lnvert Elevat¡on (ft-m) Piæ Material Tvoe Finish Grade Elevat¡on (ft . m) Area (acres. h¿) Incom¡n9 Slop€ (oô) Runoff Coeff¡c¡ent c Estimated Groundwater Elevation (ft . m) Is the system subject to H-20 load¡n9s? Ye5 or NO Special Site Conditions or Requirements: How did you learn about Aqua-ShieldrM ? Ptease provide copy of Site Plans showino orientation (1) Water Quality Treatment Flow ¡s presr¡bed by local regulatory agenc¡es to achieve full treatment of spec¡fìc amount of stormwater. (2) Peak Design Flow refers to maximum calculated flow fot an outfall or recurrence ¡nteruôl (1o-yr, 25-yr event) Specifier's Signature:Date: g AqUa-swirltt sizing chart (Enstish) 1) The Aqua-SwirllÛ Conveyance Flow Diversion (CFD) provides full treatment of the "first flush," white the peak design storm is diverted and channeled through the main conveyance pipe. Please refer to your local representative for more information. Z) Many regulatory agencies are estabtishing "water quality treatment flow rates" for their areas based on the initial movement of pollutants into the storm drainage sysfem, Ïhe treatment flow rate of the Aqua-Swirlffi sysfem is engineered to meet or exceed the local water quatity treatment criteria. fh,s "water qualìty treatment flow rate" typicatly represenfs approximately 90% to 95% of the total annual runoff volume. The design and orientation of the Aqua'FilterrM generally entails some degree of customization. For assistance in design and specific sizing using historical rainfall data, please refer to an AquaShieldil representative or visit our website at www.AquaShieldlnc.com, CAD details and specifications are available upon request. Swirl I Maximum I Water Qualityl oit¡oenris Chamber I Stub-Out Pipe I Treatment I Storage Diameter I Outer Diameter I rlowt I Capacity (ft.)l(¡n.)l(cfs)l(gal) Sediment Storage Capacity (ft') Aqua-Swirl" Model 10 20 32 45 65 90 115 L45 180 270 2.50 3.25 4.25 5.00 6.00 7.00 8.00 9.00 10.0 12.0 Custom 1.1 1.8 3,2 4,4 6.3 8.6 tL,2 L4.2 t7.5 25.2 >26 37 110 190 270 390 540 7LO 910 1130 1698 AS-2 AS-3 AS-4 AS-5 AS-6 AS-7 AS-8 AS-9 AS-10 AS-12 AS-XX 8 10 t2 L2 L4 16 18 20 22 24 L2 16 18 24 30 36 42 48 54 48 *Higher water qual¡ty treatment flow rates can be deslgned wlth mult¡ple swlrls. g Aqua-Swirltt sizing chart (Metric) 1) The Aqua-SwirlrÛ Conveyance Flow Diversion (CFD) provides full treatment of the "first flush," while the peak design sform is diverted and channeled through the main conveyance pipe. Please refer to your local representative for more information. 2\ Many regulatory agencies are esfab/lshing "water quality treatment flow rates" for their areas based on the initial movement of pollutants into the storm drainage system. The treatment flow rate of the Aqua-Swrlw sysfem is engineered to meet or exceed the local water quality treatment criteria. fhß "water quality treatment flow rate" typically represenfs approximately 90% to 95% of the total annual runoff volume. The design and orientation of the Aqua-Filteril generally entails some degree of customization. For assistance in design and specific sizing using historical rainfall data, please refer to an AquaShieldrM representative or visit our website at www.AquaShieldlnc,com. CAD details and specifications are available upon request. Swirl Chamber Diameter (mm.) Oil/Debris Storage Capacity (L) Sediment Storage Capacity (m') Maximum I Water QualitY Stub-Out Pipe I Treatment Outer Diameter I F¡owt 0.28 o.57 0.91 t.27 1.84 2.55 3.26 4.11 5.10 7,65 762 991 1295 L524 1829 2L34 2438 2743 3048 3658 Custom 31 51 91 125 L78 243 3L7 402 495 7t3 >7L3 140 4L6 7t9 LO22 L476 2044 2687 3444 4277 6427 AS-2 AS-3 AS-4 AS-5 AS-6 AS-7 AS-8 AS-9 AS-10 AS-12 AS-XX 203 254 305 305 356 406 457 508 559 610 305 406 457 610 762 9L4 LO67 t2L9 L372 t2L9 *Higher water qual¡ty treatment flow rates can be designed wlth mult¡ple sw¡rls. ;'1r.¡..:.-i.ii ¡.:-iiJ ' : fl'r7 Aqua-Swirl" Sample Detail Drawings Sample Aqua-Swirl" detail drawings are provided as examples of the type of systems that AquaShield'" can offer for a specific work site. -;- -' l-ï.ií;¡ I a .:^ra'¡. -.-j{-,rr.r'x'.-r1!.11 þ: II -7 '\l- c .n..-.-. , , Ili*...."1 ' -:{---'J¡i -a_-.¡l?h! !!!!Ir_--æ!f=5r5r:st g"gsglFuo'o*ffio,, ::i i''l¡ t - t rt¡ t t,'r i.'¿s-Bi+ ¿.0 nri ;: [:i Ì!.,.1o{oE' ri. Fllaatro,iJ.)io ".;r'¿ 8.jr!i ú:Jtt, iìl.ìl ,,, i'I ,f")-._:- :3 ii-ù ::,rj¡ :\ - l3 JTANDARD NOTE: System shall be deslgned for the followlng capaclties: Swirl Treatment Flow: 1.1 cfs Sw¡rl Sediment Storêge: l0 ft¡ Swll Oll/Debrls Storage: 37 gal. Pleaseseeaccompanled Agua-Sw¡rl speclfication notes. See Site Plan for actual system or¡entat¡on. 12314" OD Octagonal Base Manhole Frame and - Rim elevations to match fìnished Cover by Manufacturer. \ l- 32,' OD -+l f Orud". HDPE risers can be field (See Detail) \ I V cut bY contractor. I Pipe coupling by Contractor. 12" long Stub-out by Manufacturer. -T-- I _-l Plan View Bollards shall be placed around rlse(s) ln non-traffic areas to prevent lnadvertent loadlng by malntenance vehic,les. L2"r Bedding Undisturbed Soil T--'--'------1 Cråd &xlol di 4:d úkrc l.5ld òF¡.d íí6¡süf cl)¡dr¡r nø ls lù cffiù¡rd{hM4 r&r) u&u.N*.(kr¡3 ! \_ Grdd Sa.tfil '.. ìrl G@d 8âddu 's Pl¿cê ftÍ ¿m@d ot ]waetooogtrø ^ --..--J levelNnholcfràm. DO NOT ¡Ìow màn¡olc lrðtu to rd upon HoPÉ rlgr. Section A-A Aqua-Swirl Concentrator Model AS-2 CFD Standard Detail ua-Swirltt S cificationsu GENERAL This specification shall govern the performance, materials and fabrication of the Stormwater Treatment System. SCOPE OF WORK The Aqua-Swirlru shall be provided by AquaShield", lnc., 2733 Kanasita Drive, Chattanooga, TN (BBB-344-9044), and shall adhere to the following material and performance specifications at the specified design flows and storage capacities. MATERIALS A. Stormwater Treatment System shall be made from High-Density Polyethylene (HDPE) resins meeting the following requirements: 1) HDPE Material - The HDPE material supplied under this specification shall be high density, high molecular weight as supplied by manufacturer. The HDPE material shall conform to ASTM D3350-02 with minimum cell classification values of 345464C. 2) PHYSTCAL PROPERTTES OF HDPE COMPOUND a) Density - the densiÇ shall be no less than 0.955 g/cm3 as referenced in ASTM D 1505. b) Melt Index - the melt index shall be no greater than 0.15 g/10 minutes when tested in accordance with ASTM D 1238- Condition 19012,t6. c) Flex Modulus - flexural modulus shall be 110,000 to less than 160,000 psi as referenced in ASTM D 790. d) Tensile Strength at Yield - tensile strength shall be 3,000 to less than 3,500 psi as referenced in ASTM D 638. e) Slow Crack Growth Resistance shall be greater than 100 hours (PENT Test) as referenced in ASTM F 1473 or greater than 5,000 hours (ESCR) as referenced in ASTM D 1693 (condition C). l5 Aq u a Sh iel d'''' Storr lrwa te r -f reatrn ent Sol r-r tio lls Ð Hydrostatic Design Basis shall be 1,600 psi at 23 degrees C when tested in accordance with ASTM D 2837.g) Color - black with minimuffi 2o/o carbon black. B. REJECTION - The Stormwater Treatment System may be rejected for failure to meet any of the requirements of this specification. PERFORMANCE A. The Stormwater Treatment System shall include a _-inch inner diameter (ID) circular hydrodynamic flow-through treatment chamber to treat the incoming water. A tangential inlet shall be provided to induce a swirling flow pattern that will cause sedimentary solids to accumulate in the bottom center of the chamber in such a way as to prevent re-suspension of captured particles. An arched baffle wall shall be provided in such a way as to prevent floatable liquid oils and solids from exiting the treatment chamber while enhancing the swirling action of the stormwater. B. The Stormwater Treatment System shall have a sediment storage capacity of _ cubic feet and be capable of capturing _ gallons of petroleum hydrocarbons. The Stormwater Treatment System shall have a treatment capacity of _ cubic feet per second (cfs). The Stormwater Treatment System shall be capable of removing floating trash and debris, floatable oils and B0o/o of total suspended solids from stormwater entering the treatment chamber. C. Service access to the Stormwater Treatment System shall be provided via 3O-inch inner diameter (ID) access riser(s) over the treatment chamber such that no confined space entry is required to perform routine inspection and maintenance functions. TREATMENT CHAMBER CONSTRUCTION A. The treatment chamber shall be constructed from solid wall HDPE ASTM F 7I4 cell class 345464C. For sizes above 63-inch OD, the treatment chamber shall be constructed from profile wall HDPE ASTM F 894 RSC 250 pipe or solid wall HDPE. B. The bottom thickness of the treatment chamber will be determined in accordance with ASTM F L759. Calculations must be provided to justify the thickness of the bottom. 16 AquaShield'* Stormwater Treatment SoiL¡tions C. The inlets and outlets shall be extrusion welded on the inside and outside of the structure using accepted welding methods. D. The arched baffle wall shall be constructed from HDPE and shall be extrusion welded to the interior of the treatment chamber using accepted welding methods with connections made at 180 degrees of each end. E. HDPE lifting supports may be provided on the exterior of Stormwater Treatment System in such a way as to allow prevention of undue stress to critical components of Stormwater Treatment System during loading, off-loading, moving operations. The lifting supports shall be constructed as an integral part of the treatment chamber and extrusion welded using accepted welding methods. F. The top of the treatment chamber shall be built to the requirements of the drawings. Deep burial applications shall require a reinforced HDPE top. Reinforced concrete pads spanning the treatment chamber will be required with traffic rated frames and covers when the Stormwater Treatment System is used in traffic areas. A professional engineer shall approve the design of the concrete pad and the calculations must be included in the submittal. The manufacturer, upon request, can supply anti-flotation/ buoyancy calculations. In addition, typical drawings of the AquaShield" Stormwater Treatment System with concrete anti- flotation structures can also be provided. Anti-flotation structure design and approval are ultimately the responsibility of the specifying engineer. The contractor shall provide the anti-flotation structures. INSTALLATION A. Excavation and Bedding The trench and trench bottom shall be constructed in accordance with ASTM D 232L, Section 6, Trench Excavation, and Section 7, Installation. The Stormwater Treatment System shall be installed on a stable base consisting of t2 inches of Class I stone materials (angular, crushed stone or rock, crushed gravel; large void content, containing little or no fines) as defined by ASTM D 2321, Section 5, Materials, and compacted to 950/o proctor density. the the the and t7 Aq uaSlriel d "n Stor'írrt¡relter I reattnent Sol ution.q All required safety precautions for the Stormwater Treatment System installation are the responsibility of the contractor. Backfill Requirements Backfill materials shall be Class I or II stone materials (well graded gravels, gravelly sands; conta¡ning little or no fines) as defined by ASTM D 232I, Section 5, Materials, and compacted to 900/o proctor density. Class I materials are preferred. Backfill and bedding materials shall be free of debris. Backfilling shall conform to ASTM F L759, Section 4.2, "Design Assumptions." Backfill shall extend at least 3.5 feet beyond the edge of the Stormwater Treatment System for the full height to sub grade and extend laterally into undisturbed soils. Pipe Couplings Pipe couplings to and from the Stormwater Treatment System shall be Fernco@, Mission" or an equal type flexible boot with stainless steel tension bands. A metal sheer guard shall be used to protect the flexible boot. DIVISION OF RESPONSIBILITY A. Stormwater Treatment System Manufacturer The manufacturer shall be responsible for delivering the Stormwater Treatment System to the site. The system includes the treatment chamber with debris baffle, inlet and outlet stub-outs, lifting supports, 30-inch ID service access riser(s) to grade with temporary cover(s), and manhole frame(s) and cover(s). B. Contractor The contractor shall be responsible for preparing the site for the system installation including, but not limited to, temporary shoring, excavation, cutting and removing pipe, new pipe, bedding, and compaction. The contractor shall be responsible for furnishing the means to lift the system components off the delivery trucks. The contractor shall be responsible for providing any concrete anti- floatation/anti-creep restraints, anchors, collars, etc. with any straps or connection devices required. The contractor shall be responsible for field cutting, if necessary, and HDPE seruice access risers to grade. The contractor shall be responsible for sealing the pipe connections to the Stormwater Treatment System, backfilling and furnishing all labor, tools, and materials needed. c. l8 Aq uaShield''' Stormwa ter l-reatnrent Sol utions SUBMITTALS The contractor shall be provided with dimensional drawings; and when specified, utilize these drawings as the basis for preparation of shop drawings showing details for construction and reinforcing. Shop drawings shall be annotated to indicate all materials to be used and all applicable standards for materials, required tests of materials, and design assumptions for structural analysis. Shop drawings shall be prepared at a scale of not less than 1/c inch per foot. Three (3) hard copies of said shop drawings shall be submitted to the specifoing engineer for review and approval. QUALTTY CONTROL TNSPECTTON A. Materials The quality of materials, the process of manufacturing, and the finished sections shall be subject to inspection by the specifying engineer. Such inspection may be made at the place of construction, on the work site after delivery, or at both places. The sections shall be subject to rejection at any time if material conditions fail to meet any of the specification requirements, even though sample sections may have been accepted as satisfactory at the place of manufacture. Sections rejected after delivery to the site shall be marked for identification and shall be removed from the site at once. All sections, which are damaged beyond repair after delivery will be rejected; and, if already installed, shall be repaired to the specifying engineer's acceptance level, if permitted, or removed and replaced entirely at the contractor's expense. B. Inspection All sections shall be inspected for general appearance, dimensions, soundness, etc. C. Defects Structural defects may be repaired (subject to the acceptance of the specifying engineer) after demonstration by the manufacturer that strong and permanent repairs will be made. The specifying engineer, before final acceptance of the components, shall carefully inspect repairs. l9 rc! - tt Ua-SWifltt Sizing Chart (Enstish) Swirl Chamber Diameter (ft.) Oil/Debris Storage Capacity (gal) Sediment Storage Capacity (ft') Maximum lWater Quality Stub-Out Pipe I Treatment Outer Diameter I Flowt 2.50 3.25 4.25 5.00 6.00 7.00 8.00 9.00 10.0 12.0 Custom AS-2 AS-3 AS-4 AS-5 AS-6 AS-7 AS-8 AS-9 AS-10 AS-12 AS-XX 1.1 1.8 3.2 4.4 6.3 8.6 11.2 L4.2 L7.5 25.2 >26 37 110 190 270 390 540 7LO 910 1130 1698 10 20 32 45 65 90 115 145 180 270 I 10 L2 L2 L4 16 18 20 22 24 L2 16 18 24 30 36 42 48 54 48 *Higher water quality treatment flow rates can be des¡gned w¡th multiple swirls, (1) The Aqua-Swirl'" Conveyance Flow Diversion (CFD) provides full treatment of the "fìrst flush," while the peak design storm is diverted and channeled through the main conveyance pipe. Please refer to your local representative for more information. (2) Many regulatory agencies are establishing "water quality treatment flow rates" for their areas based on the initial movement of pollutants into the storm drainage system. The treatment flow rate of the Aqua-Swirll' system is engineered to meet or exceed the local water quality treatment criteria. This "water quality treatment flow rate" typically represents approximately 90o/o to 95o/o of the total annual runoff volume. Aquashield9" SIORMWAI'EN TREATMENT SOLUÎIONS 2733 Kanaslta Dr. Ghattanooga, TN 37343 888.344.9044 www.AquaSh ieldlnc.com The design and orientation of the Aqua-Swirl'" generally entails some degree of customization. Local regulations vary widely for the sizing of all stormwater quality treatment devices. Always consult your AquaShield representative for current sizing requirements for your area. You may find contact information for all AquaShield representatives at www. AquaShieldinc.com, or under the AquaShield tab of the technical manual. You may also contact AquaShield'" inc. at 1-888-344-9044. CAD details and specifications are available upon request. urlz Ua-SWifltt Sizing Chart (Metric) (1) The Aqua-Swirl'" Conveyance Ftow Diversion (CFD) provides full treatment of the "first flush," while the peåf ¿es¡gn storm is diverted and channeled through the main conveyance pipe. Please refer to your local representative for more information. (2) Many regulatory agencies are establishing "water quality treatment flow rates" for their areas based on the initial móvement of pollutants into the storm drainage system. The treatment flow rate of the Aqua-Swirl'" system is engineered to meet or exceed the local water quaiity treatment criteria. This "water quality treatment flow rate" typically represents approximately 90o/o to 950/o of the total annual runoff volume. The design and orientation of the Aqua-Swirl'" generally entails some degree of customization. Local regulations vary widely for the sizing of all stormwater qual¡ty treatment devices. Always consult your AquaShield representative for current sizing requirements for your area. You may find contact information for all AquaShield representatives at www. AquaShieldinc.com' or under the AquaShield tab of the technical manual. You may also contact AquaShieldrm inc. at 1-888-344-9044. CAD details and specifications are available upon request. åg-qe9.his!$"H 2733 Kanaslta Dr. Chattanooga, TN 37343 888.344.9044 www.AquaShieldlnc.com t Aqua-Swirl-' Model Maximum Stub-Out Pipe Outer Diameter (mm.) Water QualitY Treatment Flow2 (L/s) Swirl Chamber Diameter (mm.) Oil/Debris I Sediment Storage I Storage Capacity I Capacity (L) | {m') 0.3 0.6 0.9 1.3 1.8 2.6 3.3 4,L 5.1 7,7 31 51 91 L25 L78 243 3L7 402 495 7L3 >7L3 140 416 7L9 t o22 t476 2044 2687 3444 4277 6427 762 991 1295 L524 1829 2t34 2438 2743 3048 36s8 Custom AS-2 AS-3 AS-4 AS-5 AS-6 AS-7 AS-8 AS-9 AS-10 AS-12 AS-XX 30s 406 457 610 762 9L4 t,067 1219 L372 L2L9 203 254 305 305 356 406 457 508 559 610 *H¡gher water quality treatment flow rates can be des¡gned w¡th multlple sw¡rls. AquaShieldp'" lj I l.JRMwl\I LR I Rt.AI MENI SIJLUII(JN:j ,',,., .'. .,/.,t.¡'.r.1 l, I i,-'i,.l i r ì ';.L \,' r ; ì AquaShield'', Inc. 2733 Kanasita Drive, Suite B o Chattanooga, TN 37343 Phone: (888) 344-9044 o Fax: (423)826-2LLz www.AquaShieldlnc.com Aqua-Site Worksheet Project Information Project Name: Specifier Information Locatlon (City, stãte)! Site Use (clrcle one): S¡te Plan Attachedi Pollutànts (rSS, Floatåble Debr¡t olls/greåse, 1P, etc.): Residential Commer¡cal Industrial I vrs E*o Other Deslgner's Name: Design Firm: Address¡ Clty, State, Zipl AutoCAD Versioni Date Subm¡ttedl Phone: Fax: E-malh Specifications Un¡t tâbel or Mânhole Numbs AquaShietdrt Model Design Flow Ratè ¡nlet/Outlet Pipe R¡m D¡alnage Areã Info Traff¡c Loads Water Quality Treatment Flowr (cfs - Us) Peak 0es¡9n Florv¡ ((ls . L/s) S¡ze (lD) (in . mm) lnlet Elevation (ll.m) 0utlet Elevation (fi-m) P¡pe Material Tvæ tinish Grade Elevat¡on (ft.m) Area (ac.es . h¿) ¡ncom¡nq Sloæ (%) Estimated Groundwater €levation (n-m) ¡s the system subjed to H.20 loadings? Ys or No Special Site Conditions or Requirements: How did you learn about Aqua-ShieldrM (l) Water Quality Treatmenl Flow ls presrlbed by local regulatory agencies to achieve full treatment of spec¡flc amount ot stormwôter. (2) Peak Deslgn Flow refers to maxlmum calculôted flow for an outfall or recurrence lnterual (10-yr. 25-yr event) Soecifier's Sionature:Date: ú[v Aq ua-Swirl" Insta I lation Normal installation steps for the Aqua-Swirl'* units involve preparation and excavation of the area that is to contain the Aqua-Swirl". This includes grading, leveling, and compacting the base material before lowering the unit into the excavation and connecting the Aqua-Swirl" inlet and outlet stub-outs with appropriate pipe couplings. Prior to shipping, the purchasing contractor provides written confirmation to install AquaShield" products in accordance with manufacturer's specifications. Step 1- Excavation and Bedding The trench and trench bottom shall be constructed in accordance with ASTM D 232L, 6, Trench Excavation, and Section 7, Installation. The excavation pit is best positioned slightly off- set of the center line of the incoming drain pipe trench because of the tangential inlet pipe connecting to the Aqua-Swirl" Concentrator. The Swirl Concentrator shall be installed on a stable base consisting of L2- inches of Class I stone materials (angular, crushed stone or rock, crushed gravel; large void content, containing little or no fines) as defined by ASTM D 232L, Section 5, Materials, and compacted to 95o/o proctor density. All required safety precautions for Aqua-Swirl" installation are the responsibility of the contractor. Step 2 - Pipe Connection Devices Couplings to and from Aqua-Swirl" Concentrator shall be supplied by the contractor and shall be Fernco@, Mission" or equal type flexible boot with stainless steel tension bands or equal. A metal sheer guard should be used to protect the flexible connector. On-site excavation The coupling between the Aqua- Sw¡r|Î" and the PiPe Step 3 - Backfill Requirements Backfill materials shall be Class I or II stone materials, (well graded gravels, gravelly sands; content, containing little or no fines) as defined by ASTM D 232t, Section 5, Materials, and compacted to 90o/o proctor density. Class I materials are preferred. Backfill and bedding materials shall be free of debris. Backfilling shall conform to ASTM F L759, Section 4.2, "Design Assumptions". Backfill shall extend at least 3.5 feet beyond the edge of the Swirl Concentrator and for the full height to sub-grade and extend laterally to undisturbed soils. Sufficient backfill shall be placed over components prior to using heavy compaction or construction equipment to prevent damage. Support shall be provided for vertical risers as commonly found at service connections, cleanouts, and drop manholes to preclude vertical or lateral movement. Step4-Traffic Loading A reinforced concrete pad shall be placed over the entire Aqua-Swirl" when subject to H-20 (or greater) traffic loading. The pad shall extend no less than 12 inches beyond the outside diameter of the Aqua-Swirl'*. A professional engineer shall provide final approval of the design of the concrete pad and the calculations must be included in the submittal. Traffic rated foundry rims and covers shall be installed such that no contact is made between the HDPE access riser and cast iron frame. Step 5 - Non-Traffic Loading Bollards shall be placed around access risers in non-traffic areas to prevent inadveftent loading by maintenance vehicles. Class I backfill material around the Aqua-Swirl'" A relnforced concrete pad for H'20 traffic loading Í[v Aqua-Swirl" Sample Installation Details Aqua-Swirl'" Sample Concrete Pad Detail Aqua-Swirllm Sample Manhole Detail Aqua-Swirll' Bollard Detail * Concrete Propefties* Alr Entralned Concrete*Slump<5inch * Coarse Aggregate < I inch* Properly Cure Concrete for 5 DaYs* Compressive Strength at 28 Days - 3,000 p.s.i. * Concrete Covs 3 lnch for All Reinforcing Bar * Reinforcing Properties* Reinforcing Bars ASTM 4615 Grade 60 * Welded Wire Fabric (WWH) ASTM 4185 Sheets Only * Design Criteria* H-25 Loadlngs* Impact Factor - 30o/o * Codes* ACI 318 Building Code for Reinforced Concrete * ASTM F1759 - Design of HDPE Chamberfor Su bsurface Applicatlon* ASTM D232L - Crushed Stone Compaction Criteria * ExcåYaüon* Slopcs should bê constructcd ¡n rccordtncc w¡th osHA standards. w¡thoùt any spcdl¡c dcta¡|s of excavadon depth and måtctLl type, excavadon slopes should bê no stcêper than 2:1 (hotLont¡l- vertical). ¡f stcepcr 6lop€ ãrr das¡rcd, sftG sp€dfic lnformatlon regardlng cxcavaüon depth and/or deslrcd slope hcght should bc forwarded to thc Englneer, standard Slab slzes For Coverlng Swlrl Chambers Châmbcr Oulcr dhmctcrl¡Ll Itldth x lcngth x Ocpt'l(FL) RcqülÉd Rcb.r(6"o.c.) Ê!chw.y Conæte Volsm ¡n cublc Yrrdt AS-2 2.7 6x6x13 *5's 1.¡l AS-3 3.5 6x6¡13 #5'6 1.4 ^s-ó 4.5 6.5x6.5x13 *5's t.7 as-5 5.6 t.5x7.S ¡13 *6's 2.3 A5-6 6,'8,5x8.5¡13 S6's 2,9 AS-7 7,4 10xlox13 #7's t.o AS.8 8.9 llx11x13 l8's ¡1.9 AS-9 10.0 12t12t11 *8'6 6.2 AS.tO 11,1 13rt3x¡¡t *9's 7.3 4S.12 13.0 15x15¡14 #¡0!9,? Rebar Depths l" Clear (Typ.) TYPICAL DETAIL FOR TOP BARS FOR ALL CHAMBER SIZES 6"O.C.E.W., Typ. Top Bars # 5's @ 4" Spaclng and 50" +/- Long 4" O.C.E.W., Typ. HDPE Swirl Chamber I I ø2L8" HDPE Manway Bottom Bars (see table) No Contact Between HDPE Riser and Frame Eofú @ io Top Bars #5 Bars @ 4" Spacing Around Bottom Bars (see table) PLAN (Slab # AS-4 - as shown; others - simllar) Manhole Frame and Cover Rim Elevat¡on to Match Flnlshed Grade HDPE Swhl Chamber 3" Pavement 4" Frame Depth 30'Innér Dlameter Rlser Swlrl / Chamber Top -J lload Compatlble. Stone Backflll wlth 95o/o Proctor Denslfy li I i ttrrs 's a S.rrnple Dct.ril, Ple¿se corìtaci ¡\quasiìield, ¡nc. for morc lnforrrlatìcrr ASTM 02321 Class tI crushed i Stone Bacmll wlth 90o/o i Proctor Density I I I I I l U.S. Patent No. 6524473 | i"ì;.ì; - I ôä ñiiò; "f RÑ"n l:::_-_j- -- l:_-_-l, ____-i__ _,_ _- r l - - -r.IÞ.1919È N". 65214ll-:. .] ï-:ì.J 't.. I '1{,'/ irl Stormwater SECTION :t;-.üfr - Bollards shall be placed around access riser(s) in non-traffic areas to prcvent inadvertent loading by maintenance vehicles. l*---- Manhole Frame & Cover Detail For Non-Traffic Areas Only NTS If traffic loading (H-20) is required or anticipated, a @ncrete pad must be placed over the enti¡e Stormwater Treatment System. Sample details of concrete pad available upon rcquest. cover-l If traffic loading (H-20) is required or anticipated, a concr€te pad must be placed over the entire Stormwater Treatment System. Sample details of concrete pad avallable upon rcquest. Place small amount of concrete to suppo{t and level manhole frame. DO NOI allow manhole frame to rest upon HDPE rls€r. Gravel Backnll ./r' Manhole Frame & Cover Deta¡l For H-20 Trafñc Loading Areas NTS ,.,1, ir'..ì 'ii'. ,.;..i.i l, ,., ,.,i i*(.1ì l¿i l¡ í 'a;t ril¡;ir ' ;.'i li.' ;'.1lir { ()\'i i'.,¿,i1, .' r 'i : rt' Shield$ r,(.r11l'¡i:Iii)i Conc. Top To Be 172" Thick At Center And Conc, Must Over Lap Edge of Pipe, 6" Dia. STL, Pipe fìll w/Conc. Finish Grade 42" 42" AquaSñ¡Eldg gIOFHWAITF TFEAIMCNI àOLI'TION3 2733 Kanasit¿ Drive, Suite B, Chattanoosa, TN :I Kanasit¿ Drive, Suite B, Chattanooga, TN 37343 Phone (888) 344-9044 Fax (a23) 870-100s r¡rww.acluashieldinc,coin Bollard Detail APPENDIX A-7 - MOUNDING ANALYSIS TECHNICAL MEMORANDUM LANDAU ASSOCIATIS ÍtJvÍONr.fN¡AI I G€OItCrßrC¡¡ i ¡{^II,R¿ eËS(l¡CtS TO: FROM: DATE: Rr: Tim Holderman, P.8., Sound Engineering Eric Weber, L.Hg., Anthony Farinacci June 16,2008 RBsuLrs oF MoUNDINc ANALYSIS Yrlnr Mrxpn Usr Ynlrrl, WesHlllcro¡l INrRooucrro¡l This technical memorandum presents the results of a mounding analysis conducted for the proposed Creek Road mixed use project (site) located at the northeast corner of Creek Road and Yelm Avenue (SR 507) at the address 10520 Creek Road S.E., Yelm, Washington 98567 (Figure l). The site parcel numbers are 64303400400 and 64303400501. The total area of the parcel is I 1.06 acres. The development will include stormwater facilities, utilities, public and private roadways, parkirrg lots, and open space. In additiorr, three commercial buildings totaling 6.02 acres on tax parcels 64303400501 and 64303400502 will be included in the development plan. The anticipated stormwater runoff fro¡n the impervious areas will be directed into four different infiltration basins identified as Basin I (0.34 acres), Basin 2 (0.14 acres), Basin 3 (0.05 acres) and Basin 4 (0.02 acres). The mounding analysis was performed to estimate the potential impacts to groundwater levels at the property boundaries. The standard that is applied to the Thurston County Critical Areas Ordinance for the Salmon Creek Basin and Other High Groundwater Areas (City of Tumwater website 2005) was used as the basis for estimating mounding impacts. The concept is to evaluate groundwater level changes at the property boundary and on site. A change of less than 0.5 ft is considered to be no impact. In other words, impacts are rounded to the nearest foot. To evaluate the impacts in the Salmon Creek basin (located south of Tumwater, V/A), a series of County guidelines were developed and presented in the Groundwater Mounding Analysis Guidelines Memorandum (the memorandum) (Pacific Groundwater Group 2000). The memorandum guidelines were applied to the mixed use site with a number of modifications to adapt the analysis to the Yelm area and to simplifo the analysis. These modifications are summarized below: o The memorandum proposes using the HSPF model and performing an analysis of long-term monthly recharge for water years 1997, 1998 and 1999 based on relationships and information in the Salmon Creek basin. For this site analysis, runoff was estimated from the rainfall hyetograph established for Thurston County in the Drainage Design and Erosion Control Manual þr Thurston County (1994). This approach used a24-hr 100-year design storm event to look at water level impacts rather than long-term seasonal impacts proposed in 950 PacifìcAvenue, Ste.515 . Tacoma, WA 98402 . (253) 926-2493 . fax (253) 926-2531 . www.landauinc.com the memorandum. This was a simplifuing assumption that is considered conservative in that intense short term storm events should produce relatively higher peaks then average monthly events. As a result, the numerical model was designed to have 1-hr time steps rather than 1- month time steps. Calibration was done qualitatively based on best professionaljudgment since no onsite water level data was available for calibration Evapotranspiration was not taken into account. This adjustment was made to simplify model setup. The effect of evapotranspiration will have a minimal effect on a 100 yr storm (which will likely occur between October and March) as precipitation greatly exceeds ET at this time (Drost et al., 1999). Onsite water levels vvere not correlated to County reference well data since this data does not exist in the Yelm area. Aquifer properties were based on the Yelm specific Ecology Report (Erickison 1998). A hydraulic conductivity value of 4,800 ft/day was used. This value is the low (conservative) end of the range of values presented in Yelm Groundwater Baseline Sampling (Erickson 1998). In the absence of site specific data, the memorandum suggests using values from the region USGS Thurston County model(Drost et al. 1999) Moonl Snrup In order to quantif the potential impacts from the proposed mixed use area on groundwater levels, a mounding analysis was conducted using a numerical groundwater model to simulate the groundwater conditions beneath the site. The numerical model was developed usirrg Groundwater Vistas graphical user interface to the U.S. Geological Survey (USGS) MODFLOW code (ESI 2004;Harbaugh et al, 2000). The code was solved using the preconditioned conjugate gradient 2 solver package (Hill 1990). The model was set up in general accordance with the mounding analysis procedures established by Thurston County In the memorandum. The modelwas set up with a cell grid size of l0 x l0 ft. The model boundaries were established at a distance of 10 times the dimensions of the site, per the memorandum. Yelm Creek runs adjacent to the property and was modeled as a constant head boundary. The constant head boundaries to the south and to the north were assigned a head value of 3 50 ft and 340 ft, respectively. The model boundaries are shown on Figure 2 The model was constructed as a single layer with a uniform thickness of 25 ft. The thickness of the model was derived by the observation of well logs in the site vicinity and data presented in Erickson (1998). The bottom of the model was assigned a uniform gradient that sloped from the southern boundary to the northern boundary Q25 ft to 315 ft). The saturated portion of the model represents recessional outwash deposits that are mapped as the surface deposit in the area (Drost et al. 1999). The 6/1 6/0E \\Portlandl \Oâtå\Projecls\Yelm\Mound¡ng Analysis_tm_etW.doc L¡r.¡oRu AssoctATEs recessional deposit is characterized as intermittent in the area and consists of loose sand and gravel (Erickson 1998). The recessional outwash deposit is underlain by till deposits identified by drillers as hardpan. This till represents a no flow boundary and ìs the bottom elevation of the model grid. Hydraulic conductivity of the recessional deposit is reported to range between 4,800 ff/day and 66,000 ff/day (Erickson 1998). The value 4,800 ft/day was selected to provide a conservative (high) estimate of groundwater mounding. The specific yield was initially set as 0.25 and then adjusted during model calibration to 0.15, per the memorandum. This lower value of storage represents a conservative value relative to the default assumption of 0.25.. The recharge source to the recessional outwash aquifer is primarily precipitation (Erickson 1998). RncHancn To simulate the effects of pre- and posl-development conditions, a recharge field for each condition was established. The recharge fields were derived from the 24-hr design storm hyetographs presented in the Drainage Design and Erosion Control Manual þr Thurston County (1994). The recharge field for the pre-developed condition was derived from a standard precipitation event designed to simulate a24-hr,lO0-year storm for Thurston County (6.15 inches in 24 hours). The rainfall curve was used as the recharge field applied to the model, basin storage \ilas not taken into account to be conservative. It was assumed that 100 percent of the recharge applied to the site would infiltrate under original site conditions. The post-developed recharge field for the site was established by taking the recharge that was applied to the project site and infiltrating that water as simulated runoff into projected infiltration basins (Basin l, Basin 2, Basin 3, and Basin 4). The correlation of runoff timing and precipitation rates was made for impervious surfaces by Brattebo and Booth (2004). The impervious surfaces and infiltration basins are shown on Figure 3. The recharge curves are shown on Figure 4 and the data is shown in Table L Monnl ExrcurloN AND Cer,lnRarro¡¡ A steady-state model was used to set up initial conditions for the transient model. The steady- state model was run using a recharge rate of 2l inches per year, which is equivalent to 0.0048 ft/day (Drost et al. 1999). The steady-state heads were then used as the initial heads in the transient run. These heads are shown on Figure 2. The model was then run under a transient condition and qualitatively calibrated to water level change. Reported water level changes in the recessional outwash aquifer are reported to be approximately 9 ft from March 1996to January 1997 (seasonal change) (Erickson 1998). 6/1 6/08 \\Portlând1 \Oatâ\Projecls\Yelm\Mound¡ng Analysis_tm_efw.doc L¡ruonu AssoctATEs This seasonal water level change was used as a basis for water level changes for the 24-hour transient simulation (i.e. water level changes should be less than 9 ft for a 24-hour event). The derived 24-hour, 100-year rain event was simulated with 24 stress periods with I time step for each stress period. An additional 24-hr stress period was run after the storm event to evaluate the dissipation rate of the infiltrated water (a value of 0.0048 ft/day was the recharge value for that time step). The observed water level change in the modelat established observation wells was greater than2 ft in the western part of the site for a Z4-hour event. This is considered to be reasonable for a 24-hour event. The locations of the observation wells are shown on Figure 3. All water balance errors for each stress period were less than I percent (per the memorandum). MooelRnsulrs To simulate the effects of developed site conditions, only the recharge quantity and distribution were changed over the site. To execute this, the fìrst simulation was the original 24-hour storm event with the recharge field applied evenly over the entire model (Pre-Developed Site Condition). The recharge field was then adjusted to simulate the approximate mixed use project site plan (Developed Site Condition). To simplifu the simulated site plan, the entire site was simulated as an impervious area. This was believed to be a conservative approach (i.e. more stormwater is generated). Specifically, the recharge applied to impervious areas was 0 ft/hour. The subsequent runoff was then infiltrated into Basin l, Basin 2, Basin 3 and Basin 4. Recharge quantities were estimated for each basin based off of the percentage of area that was designed to contribute to each basin. Specifically, llyo of the runoff generated was infiltrated at Basin l, 640/o of the runoff was infiltrated at Basin 2, l6yo was infiltrated at Basin 3 and 5%o was infiltrated at Basin 4. The recharge rates applied to each infiltration basin include the original recharge applied to each cell and additional recharge derived the runoff estimates designed to simulate the developed site conditions. These values are shown on Figure 4 and in Table l. The simulated impacts were tracked using a set of observation wells established along the site boundaries of the model (observation well A, B, E, H) and in the middle of the each modeled infiltration basin (observation well C, D, F, G). The greatest impacts at each location occumed during peak flows. The largest water level rise at the site boundaries was 0.3 ft at the observation well B, north of the largest infiltration basin (Basin 2). The largest water level rise at the actual infiltration basins was 2.5 ft at Basin 2. All observation well hydrographs and impacts for pre-developed and post-developed condition simulations are provided in Appendix A. According to the standards set forth in the memorandum, the groundwater impact at the property boundary is 0 ft (i.e., less than 0.5 ft). UsB or Tuls Tnc¡¡NrcAL Mnuonlnnun¡ 6/16/08 \Portlândl\Data\Pro¡êcts\Yetm\Mounding Anatysis_tm_efrv.doc L¡HoRu Assocnres Landau Associates has prepared this hydrogeologic technical memorandum for the exclusive use of SEB Inc., and its design consultants for specific application to the clesign of the proposed Yelm mixed use project. Use of this technical memorandum by others or for another project is at the user's sole risk. Within the limitations of scope, schedule, and budget, our services have been conducted in accordance with generally accepted practices of the hydrogeologic profession; no other warrant¡r, express or implied, is made as to the professional advice included in this technical memorandum. The conclusions contained in this technical memorandum are based in part upon data obtained from other groundwater studies in the vicinity of the project site. There may be some variation in subsurface soil and groundwater conditions at the project site, and the nature and extent of the variations may not become evident until construction. We appreciate the opportunity to provide hydrogeologic services on this project. If you have any questions or comme¡rts regarding the inforrnation contained in this technical memorandum, or if we may be of further service, please call. Rernnn¡¡cBs Brattebo B.O. and D.B. Booth. 2004. Long-Term Stormwater Quantity and Quality Perþrmance of Permeable Pavement Systems. In press (as of July 1,2003): Water Resources, Elsevier Press. Drainage Design and Erosion control Manual for Thurstorr county. http://www.co.thurston.wa.us/roads/devrev/drainase.pdf. Accessed June 5, 2008. 1994. Drost 8.W., D.M. Ely, and W.E. Lum, II. 1999. Conceptual Model and Numerical Simulation of the Ground-lI/ater Flow System in the Unconsolidated Sediments of Thurston County, Washington. U.S. Geological Survey Water-Resources Investigations Report 99-41 65. Erickson, D. 1998, Yelm Groundwater Baseline Sampling. Water Body No. WA-Il-l-l0cw. Washington State Department of Ecology Publication No. 98-301. January. ESI. 2004. Guide to Using Groundwater Vistas, Version 4. Environmental Simulations Inc. Harbaugh 4.W., R.B. Banta, M.C. Hill, and M.G. McDonald. 2000. Modflow-2000: The IJ.S. Geological Survey Modular Ground-Water Model-User Guide to Modularization Concepts and the Ground-Water Flow Processes. U.S. Geological Survey Open File Report 00-92. Hill, M.C. 1990. PreConditioned Conjugate-Gradient 2 (PCG2): A Computer Prog'am for Solving Ground-Water Flow Equations. Report 90-4048. Denver, Colorado. Pacific Groundwater Group. 2000. Memorandum: Groundwater Mounding Analysis Guidelines. October. Tumwater, City of, website. 2005. Ordinance No. 02005-003. http://www.ci.tumwater.wa.us/ Ordinances/O2005-003.pdf. Accessed April 14, 2008. 6/1 6/08 \\Portlandl\Data\Pro¡ects\Yelm\Mounding Anatys¡s-tm_etw.doc L¡¡lo¡u Assocl¡tEs Arr¿cnn¡sltts Figurel-VicinityMap Figure2-SiteMap Figure3-ModelSetup Figure 4 - Generated Recharge Rates for Pre-Developed and Developed Site Conditions Table I - Summary ofPre-Developed and Developed Recharge Rates Appendix A - Hydrographs for Pre-Developed and Developed Condition Simulations 6 6ü16,08 l\PorlhrdlþatatProþctr\Yeknuroundhg Analysb_tm_€ftv.doc l¡nonu Assoclqres seáfle e. Sækare Washington F- ^ tt{ I I Lnmrnu ASSOCIATES ã Data &urce: ESRI 2006 q (¡ ri a c > :r :Ì.' Legend ffi EI Constant Head Boundary Simulated lnitial GroundwaterContours (1 ft lnterval) Approximate Site Boundary Data &urce: USDA 2006 Aerial lmage LANDAU ASSOCTATES Fffffi', Constant Head Boundary Recharge Zones [-l ,r 2I. IoIu Eu O MonitoringWdls tl ModerGrid No Florv Boundary ff,i lnactive fvlodelArea 0 260 520 Scale in Feet r Data Source: USDA 2006 Aeial Image LANDAU ASSoCIATES Model Setup SEB lnc. Yelm Mixed Use Yelm, Washington . Pre-De\eloped Recharge r Basin 1 Recharge Basin 2 Recharge x Basin 3 Recharge x Basin 4 Recharge (gt, o lô ED (Esooú, 15 Time (hr) LnNonu ASSOCIATES xxx SEB lnc. Yelm Míxed Use Yelm, Washington Generated Recharge Rates for Pre-Developed and Developed Site Conditions TABLE I Pagel of1 SUMMARY OF PRE-DEVELOPED AND DEVELOPED RECHARGE RATES SEB INC. YELM MIXED USE Pre-Develop€d S¡tG Recharge Rate Time(hour) (frrhour) Basin 1 Recharge Rate(ñ/day)Bæ¡n 2 Rechargc Rate (fl,fday)Bas¡n 3 Recharge Rate (fUday)Bæin 4 Recharge Rate (ft/dayt 0.rE00 10.34 6.54 3.15 1.48 2 o.2500 t3_93 8.8r 4.25 1.99 o.3200 18.07 11.42 5.5r 2.58 4 0.4000 22.%14.51 7.OO 3.24 5 o_470D 26.42 r6.95 aJ7 3.83 6 0.6200 35.00 22.13 10.67 5.00 7 0.8200 46.42 29.60 14.27 6.69 I 5.0300 285.72 180-60 87.08 40.42 9 0.7800 44.44 28.09 r3.54 6.35 10 0.6700 37.85 23.92 'Í.53 5.41 11 0.5800 33.r9 20.98 10.'11 4.74 12 0.5400 30.91 19.54 9.42 4.42 l3 0.4700 26.59 15.81 8.ro 3.80 14 0.5200 29.44 18.61 8.97 4.21 5 0.47æ 26.94 r7.03 4.21 3.85 6 o.38(X)2'1.48 r3-58 6.55 3.O7 17 0.3300 la_64 11.78 5.68 2.æ 18 0.3000 17.16 10.85 5.23 2.45 19 0.3000 17.16 10.85 5.23 2.45 20 0.3000 17.16 10.85 5.23 2.45 21 0.3000 17.16 10.85 5.23 2.45 22 0.3000 17.16 10.85 5.23 2.45 23 o.2700 15.46 4.71 2.21 24 0.2¡100 'r3.75 8.69 4.19 r.96 6/16t2(xrg Y: \'l I t5\001.01o\R\Mounding Analys¡s-tbt LANDAU ASSOCIATES -0.5 4.4 -0.3 4.2 4.1 eo ED (ú oo o oJ 0-1 €E 0.2 0.3 0.4 0.5 u8 laflrll..rtro (! o lrl Itla I 346 Observation Well A Hydrograph SEB lnc. Yelm Mixed Use Yelm, WashingtonAî$BèY*,, o ED G' (J o o o (ú B o (ú o lll -0.5 4.4 -0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4 0.5 0.8 1 Elapsed Time (days) LANDAU ASSoCIATES r Pre-Der,elopment . Post Dewlopment Water Level Change Srrltartr.ir. SEB lnc. Yelm Mixed Use Yelm, Washington Observation Well B Hydrograph -0.5 -0.3 ô oIDÊc' 4.1 :o o o lE = 348 go G o l¡¡ 0.5u5 LANDAU ASSOCIATES 1.81.61.41.20.80.60.4 1 Elapsed Time (days) 0.2 r Pre Derclopment . Post Dewlopment Water Lewl Change a'rarrltr I I t I I a SEB lnc. Yelm Mixed Use Yelm, Washington Observation Well G Hydrograph ¡ Pre Dewlopment . Post Delelopment Water Lewl Change ô -r.5 t' (ú o ı o_,1 J o (ú = t o (g o l¡J LANDAU ASSOCIATES Observation Well D Hydrograph SEB lnc. Yelm Mixed Use Yelm, Washington ' "" , r.1rli;i ,'.1.:'\'. '. :i.:'l)i.' r -... i,:i. a a Pre Derclopment Post Derelopment Water Level Change ^ :li,- ...4_.1.-..._i..-.,iì',i'*. iil+i;;r',r,::' iÌilÌ' tT ii WrS, tiit:: : :.:, : r ;i',i;,+,,f,ii;l;i f lii!¡ir1, ;, ti ..ì':. . ::i :r.ì.ittri 'ji ..-:i. ,'i' ¡:',.1;,,,,.i i, .: ;' ,.1;;';Í- : r : '. '. ..r'::.." .¡:1i.:içi il'i .'- :','' :, i.t ':lr :1':::'..ì,-.: .t." ',,,ì'jJìt;;li .;.," '"i .i.; ..:....'' | ', ..,| , ..r ,,:.lvi. ., : ", .'i: . '. ..,.: ,, .. . .., . ....i.,. ,....., . ..i :;i::¡'.".. a:,: \'.:.9:--,.,1-- n',;;r.t,tÍ:r'i_i ; :i,ii,-:-i';:'; ì\+i:,::'rï :iäi , :-.;' i.î :.'.';'.:, ,¡,.', f.íÄr'#riii;;"'i:+iriif,ri;,&jáiiÃ',;:i\"-.r',; "r;¡.!+: .:r.,.. ,i. - ..: i- ¡b I :.;,i,'i I I :r\r.,.irj1l. :i\,:'.1;ì;: j:,-l .-ì';' .,' 1..:.:i::;r'l, .l: ,t .,.'' ': ' ' '"'..,.¡.i¡:. ; , :,;.';ì;i ri,.iú:;;'-:.'. ,,: ii , ..'. ."i:;v -':,+....ì.r. :...,.,tj:..'.':l ...!tli::!.l: | :' '-::... 'i '.'0 , *irrffi' , I :â.:.l'j r¡,. ,,:r .r .,,- ô-0.1 r3o EÐE(5sg<J o (D --0.1 €3 348 o (E o, ¡¡¡ 349 u7 u6 u5 -0.5 4.4 -0.3 -0.2 0.2 0.3 0.4 0.5 0.2 1-81.6't.41.20.80.60.4 'l Elapsed Time (days) SEB lnc. Yelm Mixed Use Yelm, Washington Observation Well E Hydrograph A'#BèY*,, -0.5 -0.4 -0.3 -0.2 -0.1 eoEtc.! o:o o 0.1 € B 0.2 0.3 0.4 0.5 go G o lll ¡ Pre Development . Post Dewlopment Water Lelel Change LANDAU Assocr^TEs r.o.ll¡1lrt a allltl SEB lnc. Yelm Mixed Use Yelm, Washington Observation Well F Hydrograph -0.5 -o.4 -0.3 -0.2 -0.1 so EDgo 0:o o 0.1 € B 0.2 0.3 0.4 0.5 o o o ut LnNonu AssocrATES I Pre Dewlopment . Post Dewlopment Water Lercl Change .]::!33!rrlrrlr¡rr SEB lnc. Yelm Mixed Use Yelm, Washington Observation Well G Hydrograph 33313rr1 r Pre Derclopment . Post Dewlopment Water Lewl Change -0.5 -0.4 -0.3 -0.2 -o'1 gt aú o0ı o o 0.1 g 0.2 0.3 0.4 0.5 o (! o ul LnNonu ASSOCIATES Observation Well H HydrographSEB lnc. Yelm Mixed Use Yelm, Washington APPENDIX A.8 _ DRAFT MAINTAN ENCE AGREEM ENT r--'-----' I I i I I I I I II I I I I II i I I I I i I I I COMMERC IAL/I N DU STRIAL AGREEMENT TO MAINTAIN STORMWATER FACILITIES AND TO IMPLEMENT A POLLUTION SOUCE CONTROL PLAN BY AND BETWEEN ITS HEIRS, SUCCESSORS, OR ASSIGNS (HEREIN,\FTER *_") The upkeep and maintenance of stormwater facilities and the implementation of pollution source control best management practices (BMPs) is essentialto the protection of water resources. All property owners are expected to conduct business in a manner that promotes environmental protection. This Agreement contains specific provisions with respect to maintenance of stormwater facilities and use of pollution source control BMPs. LEGAL DESCRIPTION: Whereas, Business Name/Owner has constructed improvements, including but not limited to, buildings, pavement, and stormwater facilrties on the property described above. ln order to further the goals of the Jurisdiction to ensure the protection and enhancement of Jurisdiction's water resources, the Jurisdiction and Business Name/Owner hereby enter into this Agreement. The responsibilities of each party to this Agreement are identified below. BUSINESS NAME/OWNER SHALL: lmplement the stormwater facility maintenance program included herein as Attachment "4." lmplement the pollution source control program included herein as AttachmentuB.' Maintain a record (in the form of a log book) of steps taken to implement the programs referenced in (1) and (2) above. The log book shall be available for (1) (3) f I I I I i'ËôıìËñ'6y lilËäiðiü;i ;iääãï '.. . .'ä¿lä;Ë;-äü;inö ffimäl iGilË;]hoúrs.TheÍogbookshallcatalo@ookit,whenitwasi done, how it was done, and any problems encountered or follow-on actions I recommended. Maintenance iiems ("problems") listed in Attachment "A" shall be I inspected on a monthly or more frequänt basis as necessary. Business i Name/Owner is encouraged to photocopy the individual checklists in Attachment iA and use them to complete its monthly inspections, These completed checklists Iwould then, in combination, comprise the monthly log book. i Submit an annual report to the Jurisdiction regarding implementation of the Iprograms referenced in (1) and (2) above. The report must be submitted on or i before May 15 of each calendar year and shall contain, at a minimum, the ifollowing: i (a) Name, address, and telephone number of the business, the person, or the firm responsible for plan implementation, and the person completing the report. (b) Time period covered by the report. (c) A chronological summary of activities conducted to implement the programs referenced in (1) and (2) above. A photocopy of the applicable sections of the log book, with any additional explanation needed, shall normally suffice. For any activities conducted by paid parties not affiliated with Business Name/Owner, include a copy of the invoice for services. (d) An outline of planned activities for the next year. THE JURISDICTION SHALL: (1) Provide technical assistance to Business Name/Owner in support of its operation and maintenance activities conducted pursuant to its maintenance and source control programs. Said assistance shall be provided upon request, and as Jurisdiction time and resources permit, at no charge to Business Name/Owner. (2) Review the annual report and conduct a minimum of one (1) site visit per year to discuss performance and problems with Business Name/Owner. Review this agreement with Business Name/Owner and modify it as necessary at least once every three (3) years. REMEDIES: lf the Jurisdiction determines that maintenance or repair work is required to be done to the stormwater facility existing on the Business Name/Owner property, the Jurisdiction shall give the owner of the property within which the drainage facility is located, and the person or agent in control of said property, notice of the (4) (3) (1) (2) specific maintenance and/or repair requ¡red. The Jurisdiction shall set a reasonable time in which such work is to be completed by the persons who were given notice. lf the above required maintenance and/or repair is not completed within the time set by the Jurisdiction, written notice will be sent to the persons who were given notice stating the Jurisdiction's intention to perform such maintenance and bill the owner for all incurred expenses. The Jurisdiction may also revoke stormwater utility rate credits for the quality component or invoke surcharges to the quantity component of the Business Name/Owner bill if required maintenance is not performed. lf at any time the Jurisdiction determines that the existing system creates any imminent threat to public health or welfare, the Jurisdiction may take immediate measures to remedy said threat. No notice to the persons listed in (1), above, shall be required under such circumstances. The owner grants unrestricted authority to the Jurisdiction for access to any and all stormwater system features for the purpose of performing maintenance or repair as may become necessary under Remedies (1) and/or (2). The persons listed in (1), above, shall assume all responsibility for the cost of any maintenance and for repairs to the stormwater facility. Such responsibility shall include reimbursement to the Jurisdiction within 30 days of the receipt of the invoice for any such work performed. Overdue payments will require payment of interest at the current legal rate for liquidated judgments. lf legal action ensues, any costs or fees incurred by the Jurisdiction will be borne by the parties responsible for said reimbursements. The owner hereby grants to the Jurisdiction a lien against the above-described property in an amount equal to the cost incurred by the Jurisdiction to perform the maintenance or repair work described herein. This Agreement is intended to protect the value and desirability of the real property described above and to benefit allthe citizens of the Jurisdiction. lt shall run with the land and be binding on all parties having or acquiring from Business Name/Owner or their successors any right, title, or interest in the property or any part thereof, as well as their title, or interest in the property or any part thereof, as well as their heirs, successors, and assigns. They shall inure to the benefit of each present or future successor in interest of said property or any part thereof, or interest therein, and to the benefit of all citizens of the Jurisdiction. Owner (3) (4) (5) Owner | öiÃîË öË'wÄsr¡iñöiöñ - i - - i.ou*rroFrHURSroN | "" On this day and year above personally appeared before me, and known to be the individual(s) described, and who executed the foregoing instrument and acknowledge that they signed the same as their free and voluntary act and deed for the uses and purposes therein mentioned. Given under my hand and official seal this day of ,20 _. Notary Public in and for the State of Washington, residing in My commission expires: STATE OF WASHTNGTON ))ss couNTY oF THURSTON ) On this day and year above personally appeared before me, who executed the foregoing instrument and acknowledge the said instrument to be the free and voluntary act and deed of said Municipal Corporation for the uses and purposes therein mentioned and on oath states he is authorized to execute the said instrument. Given under my hand and official seal this day of ,20 _. Notary Public in and for the State of Washington, residing in My commission expires: APPROVED AS TO FORM: