The URL can be used to link to this page

Storm Drainage Calcs V1C1(F IDIAN- APPRDVED oar<nnW<ii�<oi :o«uo�:. pared For: -Landmark Pacific Investors -City of Meridian RF CIVIL ENGIN.+E JU N'G Woodcrest Subdivision Meridian, Idaho Storm Drainage Report NAL ;F_N s 17011 o� 92�TgrF O F \OP��l4v 'FlN F N �-31-z.� Prepared By: Andrew Newell), P.E. Blaine A. Womer Civil Engineering 4355 W. Emerald Street, Suite 145 Boise, ID 83706 (208) 593-7555 andrew@bawce.com January 31, 2022 Project No: N1420004 ( 1(E IDIAh- APPROVED Permit Number: m Table of Contents Introduction.........................................................................................................................................1 ProjectDescription..............................................................................................................................1 SiteDescription....................................................................................................................................1 Scopeand Method...............................................................................................................................1 Existing Drainage Conditions and Analysis..........................................................................................1 DesignCriteria and Limits....................................................................................................................2 Proposed Drainage Conditions and Analysis.......................................................................................2 RetentionPond....................................................................................................................................2 SeepageBed.........................................................................................................................................3 Sandand Grease Traps........................................................................................................................3 RearLot Swale......................................................................................................................................3 Inlet, Gutter and Pipe Capacities.........................................................................................................3 AdditionalInformation........................................................................................................................3 Summary..............................................................................................................................................4 APPENDICES Appendix A - Figures Vicinity Map Post -Development Drainage Basin Exhibit Storm Water Improvement Plans Appendix B - Calculations Post -Development Runoff Calculations Retention Pond Calculations Seepage Bed Calculations Sand and Grease Trap Calculations Inlet, Gutter and Pipe Calculations Appendix C - Geotechnical Engineering and Additional Information ALLWEST (9/24/2021) C E MAN — APPROVED e. pi,�. ne.e eeee m..a to Rio ea <o .ana poa�o�e report Date: n� of �oewot�ooe. Permit Number. m INTRODUCTION The purpose of this report is to show that the storm drainage facilities for the proposed Woodcrest Subdivision (Project) are designed to meet the requirements of the City of Meridian, Ada County Highway District (ACHD), as well as the water quality requirements of the Idaho Department of Environmental Quality (DEQ). This report has been prepared at the request of the developer, Landmark Pacific Investors. PROJECT DESCRIPTION The Project consists of a residential subdivision that includes 58 lots: 54 single-family residential lots, 1 commercial lot and 3 common lots. The proposed improvements to the site include roadways, sidewalks, lot grading as well as site utilities including water, sewer, pressure irrigation, gravity irrigation and storm water management improvements. Storm water from developed areas will be collected and treated onsite. SITE DESCRIPTION The Project is located at 1789 N Hickory Way in the City of Meridian, Idaho. Refer to Appendix A for a Vicinity Map of the Project. The proposed parcel consists of undeveloped land with a rough area of 1.97 acres. SCOPE AND METHOD The Rational Method is the standard method for small catchment areas. This method was used to calculate the pre -development and post -development peak runoff rates and runoff volumes. A specialized excel spreadsheet was used to calculate runoff rates and volumes of the design storms and for sizing the drainage facilities. Autodesk Hydroflow Express version 2021 was used to verify and size curb inlets, street flooding capacity, pipe sizing and hydraulic capacity, but only a select number of analyzed pipes are included in this report. Refer to Appendix B for calculations. Runoff rates and storm volumes were established for each basin for the 25-year and 100-year storms. The Technical Guidance on Implementing the Stormwater Runoff Requirements for Federal Projects under Section 438 of the Energy Independence and Security Act document provided by the Environmental Protection Agency (EPA) is generally used to determine the peak elevation of the 0.6" storm event. EXISTING DRAINAGE CONDITIONS AND ANALYSIS The existing watershed for the Project includes roughly 1.97 acres of existing undeveloped land. The majority of the onsite areas include mostly undeveloped agricultural land with Hydrologic Type "C" soils. A runoff coefficient of C=0.12 was selected for these areas, which corresponds to pervious surfaces with average slopes (0- 2%) and Type "C" Soils. Currently, the drainage from the Project free drains from the North to the South. The runoff from the undeveloped areas of the Project generally percolates before it has the chance to leave the Project. 1 �E roiAN- APPROVED x Dlana Mx Men bond b nMl complknce wIth appIi Hiking.dae. Code daflciancI. bond at InexN.e Il need to M.-d gardlaee I. blwmatlon on aDPr pp DIa p1b., Wk9 any w repmd, are requlrM b M on the conetmctlon at Ne gme of inaxctlona. Permit Number: m DESIGN CRITERIA AND LIMITS The Geotechnical Report prepared by ALLWEST dated September 24, 2021, states ground water was not encountered in test pits, with depths extending to 13 feet below ground surface (BGS). The required 3 feet of separation between groundwater and the bottom of the infiltration facilities will be maintained. The geotechnical report also recommends an infiltration rate of 8 in/hr. The design infiltration rate used was 8 in/hr. Refer to Appendix C geotechnical engineering and additional information for soils information. PROPOSED DRAINAGE CONDITIONS AND ANALYSIS The proposed drainage system improvements consist of a gutters, curb inlets, storm pipe networks, sand & grease traps, seepage beds and retention ponds. The post -development site was broken into 2 basins. Refer to Figure 3 Post - Development Drainage Basin Exhibit. The land use type and runoff coefficients are as follows: roof areas (800 square foot (sf) portion of residence), impervious roadways, 250 sf driveways for each buildable lot and sidewalks (C=0.95); landscape areas (C=0.35). Each basin was delineated according to the tributary area contributing to each drainage structure or facility, such as gutter, inlet, pipe, catch basin inlet, etc. A design point was assigned to certain drainage structures or facilities, such as an inlet or pipe junction, and analyzed. Residential lots are proposed to be split draining, meaning the front half of the lot will drain to the street while the back half will be directed to a swale that will contain storm water runoff on the lot it was generated from. Refer to Appendix B for drainage basin peak flow rates. Design Point 1 is the point of discharge for Basin A. This basin covers approximately 0.84 acres and consists of residential lots (C=0.35) and impervious areas (C=0.95). Storm water runoff from this basin includes a combination of overland sheet flow over residential lawns as well as shallow concentrated gutter flow. Flow is intercepted by storm water inlets and directed to Pond A. Design Point 2 is the point of discharge for Basin B. This basin covers approximately 0.99 acres and consists of residential lots (C=0.35) and impervious areas (C=0.95). Storm water runoff from this basin includes a combination of overland sheet flow over common lawns as well as shallow concentrated gutter flow. Flow is intercepted by storm water inlets and directed to Seepage Bed B. RETENTION POND The retention pond shall be built per the details and keynotes shown on the civil construction plans. The primary pond has been designed to hold the storm water volume from the 100-year storm event. The primary pond includes a sand infiltration window. The primary pond shall be sloped at a minimum of 1.0% to ensure adequate K C E MAN — APPROVED e. pi,�. ne.e ce.e m..a to Rio ea <o .ana poa�o�e report Date: n� of �oewot�ooe. Permit Number. m slope to the infiltrating medium. Based on our calculations, the retention pond is adequately sized for the 100-year storm event with 90% of the storm event draining in 48-hours. Refer to Appendix B retention pond calculations for additional information. SEEPAGE BED The seepage beds shall be built per the details and keynotes shown on the civil construction plans. The seepage beds have been designed to hold the storm water volume from the 100-year storm event. The volume of seepage beds located within the right-of-way have been increased by 25% to account for sediment. Based on our calculations, the seepage beds are adequately sized for the 100-year storm event with 90% of the storm event draining in 48-hours. Refer to Appendix B seepage bed calculations for additional information. SAND AND GREASE TRAPS The proposed drainage design for the project includes three (3) 1,000-gallon sand and grease traps used as a pre-treatment facility for the contributing portions of the post development layout conditions. The sand and grease traps have been sized for handling at least the water quality storm event. Please refer to Appendix B sand and grease trap calculations for additional information. REAR LOT SWALE The rear lot swales shall be built per the details and keynotes shown on the civil construction plans. These swales will be sized to handle the 100-year storm event generated on the back half of the lots. All storm water will remain on the lot that it was generated from. INLET, GUTTER AND PIPE CAPACITIES The catch basin inlets will be built per the details shown on the civil construction plans. The system consists of a total of three (3) inlets. Based on the attached calculations, the inlets have been sized to intercept the 100-year peak flow. Refer to Appendix B for inlet, gutter and pipe calculations for additional information. The gutter capacity of the proposed roadways was verified to ensure that overtopping of the curb would not occur in the 25-year and 100-year storm event. Refer to Appendix B for inlet, gutter and pipe calculations for additional information. The storm pipes have been sized to convey the 25-year and 100-year peak flow rates. ADDITIONAL INFORMATION At this time, no permits or discharge agreements are expected to be required. 3 �fE IDEZ IAN— APPROVED Permit N.,b<r. ry SUMMARY This report determines that the design, sizing and analysis of the Project storm water system conforms to ACHD, City of Meridian, Ada County, and DEQ storm water design criteria. The post -development storm water runoff for half of the proposed residential lots and all of the roadway, curb, gutters and sidewalk, along with a portion of common lots, is to be retained and treated on site. C! �fE IDIAN— APP OVED, Th— pn h— b f . . . d ro ..11 —d ........... rePon Permit N.— APPENDIX A - FIGURES No Text APPROVED Know what's below. Call before you dig NOTE: WORK CONTAINED WITHIN THESE PLANS SHALL NOT COMMENCE UNTIL AN ENCROACHMENT PERMIT AND/OR A GRADING PERMIT HAS BEEN ISSUED. PRELIMINARY MARK BY ENGINEER REVISIONS SEAL -ENGINEER • PLANNING A BLAINE A. W O M E R • SURVEYING CIVIL CIVIL ENGINEERING ENGINEERING W• PUBLIC WORKS Boise, ID 83706, 4355 M Emerald Street, Suite 145 • 1-208-593-7444 SCALE; H V; 0 20 40 60 SHEET NO, CITY OF MERIDIAN, ID 1 OF 1 WOODCREST SUBDIVISION POST -DEVELOPMENT DRAINAGE BASIN EXHIBIT FILE NO. N1420004 �1TFI ICI( I�ti,- APPROVED / °24 I BLOCK 1 r e` L / �; e �( I 1N f 1 J i 3.51 0 2" PVC ®3.92% I /� OUTFALL(D - e 10.26' of 12" PVC ®0.50%; - 3 INV: 2612.00 D VELOCITY: 4.76 FT/S a I INLET A 4 261 w 3 N.:7 2760 885 O ¢` E.:2462522.0821 - Q �r 1 RIM:2615.93 =v 3I 3' / 1 w SUMP:261 .93 I INLET 82 INV OUT:2612.93 12" (E) J/ 2613 e` w N.:712751.5666 3 I 18.34 O RIM: 2615.66', E.:2462757.1418 SGT A 2614 ••• SMP2614.12" (S) 34 RIM:26NV UOUT:2615.34 INVIN: 2612.88' 12" PVC (W).................................gig I INV OUT: 2612.53' 12" PVC (N) a 2619a INLET BAFFLE: 2612.28' 1 2616 OUTLET BAFFLE 2612.78' _ _ _ _ _ _ _ _ • H? bI �81 2 =7--- = 71 b?JI 3 267d I 2 SGT B2 12.50' of 18" PVC 0.00% 18.91' of 12" PVC ® 12.69% RIM: 2618.22' 3 y I 161.0' I INV OUT: 261219INV IN: 2612.94' ' 1'2PPVC VC N(S) IINLET BAFFLE:: 2612.3 OUTLET BAFFLE: 2612.34' 151.00' of 18" PERFORATED OSGT 61 L C900 ®0.00%as as as s as as as as as as as as as as as 72.78' of 18" PVC @ 0.00%RIM: 2616.60'_ as -as- as as as Gs-Gs-as-as-as- INV as IN: 2612PVC (S)a INV OUT: 2612.19' 12" PVC (N)LET BAFFLE: - J INBAFFLE:E: 2612.34' OUTLET BAFFLE 2612.34'_ I a / 1 3 18 06' of 12" PVC @ 0.50% INLET Bi I 3 I / N.:712705.6055 E.:2462520.7657 RIM:2616.06 SUMP:2612.03 pl P;PI INV OUT:2613.03 12" (N) 4" MINIMUM TOP SOIL TOP OF POND ELEVATION = 2615.00' REVEGETATE POND WITH DROUGHT 3 1 TOLERANT GRASSES (NO TURF), AS APPROVED BY THE CITY 100-YEAR FLOOD 3:1 ELEVATION = 2614.75' _ BOTTOM OF POND -III=III ELEVATION = 2612.00' IIIII SAND FILTER PER IDEQ BMP 12 TO FREE DRAINING MATERIAL -III IIII-III 1 1I I II I II I II l i l=1 I I=1 I IIII-III- _ .. � IIIIIIIIIIIII1 I I� � I- �-III-i SEASONAL HIGH GROUNDWATER ELEVATION = 2607.50't 3' MIN SEPARATION TO GROUNDWATER NOTES: 1. CONTRACTOR SHALL NOTIFY THE ENGINEER IMMEDIATELY IF GROUNDWATER IS ENCOUNTERED ABOVE THE ANTICIPATED SEASONAL HIGH GROUNDWATER ELEVATION. 2. CONTRACTOR SHALL INCORPORATE ALL POND REQUIREMENTS PER IDEQ BMP 23. 3. ALL BASINS TO BE VEGETATED, INCLUDING SLOPES AND BOTTOM. SLOPES SHALL HAVE IRRIGATED TURF GRASS AS SPECIFIED PER THE LANDSCAPE PLANS. NO IRRIGATION ON BASIN FLOOR. NO WOODY VEGETATION BELOW 100-YEAR WATER SURFACE OR WITHIN 10' OF EMBANKMENT SPILLWAY, PIPES OR STRUCTURES. SEE ACHD STORMWATER MANAGEMENT BASIN REVEGEEATION GUIDANCE MANUAL AND SPECIFIC BMP'S FOR ADDITIONAL VEGETATION REQUIREMENTS. 4. EXCAVATE AND SCARIFY SUBSOIL BEFORE TOPSOIL/AMENDED SOIL IS PLACED. VEGETATE AFTER CONTRIBUTING DRAINAGE AREA HAS SITE SEDIMENT & EROSION CONTROL MEASUREMENTS IN PLACE. 5. AREAS DESIGNATED FOR BASINS SHALL BE CLEARED, GRUBBED AND STRIPPED OF TOPSOIL. TOPSOIL SHALL BE STOCKPILED AND USED AT FINAL GRADING TO ESTABLISH VEGETATION. 6. FILL MATERIALS FOR EMBANKMENT SHALL CONFORM TO UNIFIED SOIL CLASSIFICATION, SC, CH, OR CL AND MUST HAVE AT LEAST 30% PASSING THE #200 SIEVE. AREAS ON WHICH FILL IS TO BE PLACED SHALL BE SCARIFIED PRIOR TO PLACEMENT OF FILL. EMBANKMENT FILL SHALL MEET ISPWC CLASS C COMPACTION REQUIREMENTS. CONSIDERATION MAY BE GIVE TO THE USE OF OTHER MATERIALS IN THE EMBANKMENT IF DESIGNED BY A GEOTECHNICAL ENGINEER. 7. ALL PIPE OUTLETS TO BASINS SHALL BE UNEXPOSED AND FULLY BURIED WITH METAL END SECTION TO PREVENT DEGRADATION OF THE PIPE FROM WEATHER. RETENTION POND A SCALE: NTS SEEPAGE BED DIMENSIONS AND CALCULATIONS TABLE SEEPAGE BED BED LENGTH BED WIDTH BED DEPTH FINISHED GRADE TOP OF DRAIN PERFORATED PIPE BOTTOM OF DRAIN GROUND WATER 100-YR VOLUME PROVIDED ELEVATION ROCK ELEVATION INVERT ELEVATION ROCK ELEVATION ELEVATION SB-B 161.0' 10.0' 4.6' 2616.88't 2614.60' 2612.19' 2610.00' 2607.00't 4,057 CY (INCLUDES 25% FOR SEDIMENT) NOTES: 1. REFER TO THE GEOTECHNICAL REPORT PREPARED BY ALLWEST, LLC DATED SEPTEMBER 24, 2021. SEASONAL HIGH GROUNDWATER WAS NOT OBSERVED IN TEST PITS REACHING A DEPTH OF 13' BELOW EXISTING GROUND AROUND THE SEEPAGE BED AREA. 2. CONTRACTOR SHALL NOTIFY THE ENGINEER IMMEDIATELY IF GROUNDWATER IS ENCOUNTERED ABOVE THE ANTICIPATED SEASONAL HIGH GROUNDWATER ELEVATION. 3. INFILTRATION RATE USED FOR DESIGN WAS 8.0 IN/HR. SEE GEOTECHNICAL REPORT MENTIONED IN NOTE 1 FOR ADDITIONAL INFORMATION. 0 10 20 30 ® KEYNOTES 1. INSTALL GROUND WATER OBSERVATION WELL PER DETAIL SHEET C5.1. MONITORING WELL SHALL CONFORM TO THE SPECIFICATIONS AND REQUIREMENTS PER ACHD STORMWATER DESIGN GUIDELINES 8200 DETAIL 6. THE PORTION OF THE PIPE LYING IN DRAINAGE SAND MUST BE WRAPPED IN A DRAINAGE GEOTEXTILE, TYPE I PER ISPWC SECTION 2060. 2. INSTALL ONE (1) 1000 GALLON SAND AND GREASE TRAP PER ISPWC STANDARD DRAWING SD-624. BAFFLE SPACING SHALL BE 20". 3. INSTALL 161.0'x10.O'x4.6' SEEPAGE BED (SB-B). EXTEND DRAINAGE FACILITIES V (MIN.) INTO FREE DRAINING MATERIAL. CONTRACTOR TO VERIFY SEEPAGE BED IS A MINIMUM OF 25' FROM ANY DOMESTIC WATER LINE. 4. INSTALL PERCOLATION POND (POND A) PER DETAIL THIS SHEET. TOTAL RUNOFF VOLUME + 10% SEDIMENT = 2,775 CIF TOTAL POND VOLUME TOTAL VOLUME = 2,881 CIF (PROVIDED) TOTAL VOLUME = 2,523 CIF (REQUIRED) PEAK 100-YEAR WATER ELEVATION = 2614.75' GROUNDWATER ELEVATION = 2607.50'f POND BOTTOM AREA = 458 SF POND TOP AREA = 1,545 SF POND BOTTOM ELEVATION - 2612.00' POND TOP ELEVATION = 2615.00' 5. OUTFALL PROVIDE METAL END SECTION AND TRASH RACKS FOR OUTFALL. INSTALL ENERGY DISSIPATION DEVICE, ROCK RIP RAP OPTION, PER ISPWC SECTION 206 AND 2050. SHEET NOTES A. SEE SHEET C1.1 FOR GENERAL AND UTILITY NOTES. B. SEE SHEET C5.1 FOR DETAILS AND ADDITIONAL INFORMATION. C. PROVIDE WATER -TIGHT SEALS AT PIPING ENTRANCES/EXITS FOR SAND AND GREASE TRAPS AND CATCH BASINS. D. ALL STORM PIPE WITHIN ROW SHALL BE C900, WHERE COVER OVER PIPE IS LESS THAN 2 FEET. OUTSIDE OF ROW, STORM PIPE SHALL BE ADS N-12 HP PIPE OR APPROVED EQUAL, FLOWABLE FILL SHALL BE USED WHEN LESS THAN 5-FEET OF SEPARATION BETWEEN STRUCTURES. IF VERTICAL SEPARATION DISTANCE FROM WATER IS LESS THAN 18 INCHES, STORM PIPE SHALL BE C900 OR APPROVED EQUAL. E. ALL DRAINAGE STRUCTURES SHALL BE PER ISPWC STANDARDS AND THE ACHD SUPPLEMENTS TO THE ISPWC. STORM DRAIN STRUCTURES SHALL HAVE HS-25 TRAFFIC RATED LIDS UNLESS OTHERWISE SPECIFIED. F. THE CONTRACTOR SHALL COMPLY WITH ALL THE REQUIREMENTS FOR STORM WATER DISCHARGE ASSOCIATED WITH CONSTRUCTION ACTIVITY. THIS INCLUDES IMPLEMENTING THE BMP'S RECOMMENDED IN THE SWPP PLAN PREPARED FOR THIS SITE, REGULAR SITE INSPECTIONS DOCUMENTATION OF MODIFICATIONS TO THE SWPPP AND OTHER REQUIREMENTS AS SET FORTH IN THE NPDES GENERAL PERMIT. G. ALL CHANGES REQUIRE APPROVAL BY THE DESIGN ENGINEER AND CITY OF MERIDIAN. H. THE CONTRACTOR SHALL PROVIDE AND INSTALL STORM DRAIN MONUMENTS TO IDENTIFY ALL STORM DRAIN MANHOLES, SEDIMENT BOXES, DROP INLETS AND OTHER PIPE JUNCTIONS OR TERMINUSES IN ACCORDANCE WITH ISPWC SD-623. I. ALL STORM MANHOLES, COVERS, FRAMES, ETC., SHALL COMPLY WITH ACHD SUPPLEMENTAL SPECIFICATIONS AND REQUIREMENTS. J. FOR PIPES LESS THAN OR EQUAL TO 24", STANDARD MANHOLE FRAME, COVER AND RISER PER ISPWC STANDARD DRAWING SD-611. STORM DRAIN MANHOLES SHALL BE 48"0 MANHOLE (MINIMUM 2' SUMP). COVER SHALL BE MARKED "STORM WATER". K. FOR PIPES GREATER THAN 24", STANDARD MANHOLE FRAME, COVER AND RISER PER ISPWC STANDARD DRAWING SD-613A. STORM DRAIN MANHOLES SHALL BE 72"0 MANHOLE (MINIMUM 2' SUMP). COVER SHALL BE MARKED "STORM WATER". Knowwhat's below. Call before you dig NOTE: WORK CONTAINED WITHIN THESE PLANS SHALL NOT COMMENCE UNTIL AN ENCROACHMENT PERMIT AND/OR A GRADING PERMIT HAS BEEN ISSUED. SEAL -ENGINEER •PLANNING B BLAINE A. WOMER •SURVEYING A CIVIL z T T CIVIL ENGINEERING ENGINEERING W .PUBLIC WORKS BENCHMARK: SEE SHEET C 1.0 CITY OF MERIDIAN, ID WOODCREST TOWNHOMES SUBDIVISION STORM WATER IMPROVEMENT PLANS RETENTION POND AND SEEPAGE BED DETAILS SHEET NO, C5.0 FILE NO. N1420004 DRAWING STATUS FOR AGENCY REVIEW MARK 11 BY BATE APPR: BATE REVISIONS ENGINEER COUNTY Boise, ID 83706, aass w. Eme�am so-eec, s�ice Ias I-208-593-7555 SCALE; H: V; I (EI ITT( I:ti,- APPROVED FINISH GRADE 2 C'�. (... J t i o 0 0 a �a a _ I - - ,�� -- —� 1 1 _ t 1`Jt (Jt (J I ; - OPTIONAL CHAMBER STANDARD@ 0 o WELL COVER IN SIDEWALK a 4 a ° ° ° LEGEND O WELL C OVER, 8N DIAM. WATERTIGHT GALVANIZED STEEL COVER AND CANISTER. ETEO (WATERTIGHT). CON MINUS CRUSHED AGGREGATE FOR BASE 4 3/4CRETE (COLLAR), CLASS 3000 (ISPWC SECTION 703), FOR (ISPWC SECTION 802) OR MATERIAL REQUIRED STORM DRAINAGE FACILITY (LE 3" DRAIN ROCK, FILTER SAND). PVC PIPE, 4 DIAMETER ASTM D 3034 SIDE 35. 2 - STAINLESS STEEL HOSE CLAMPS AT 3" SPACING. SECURE GEOTE%11LE IN PLACE. FILTER SAND (IsPwc SECTION 801). -- O SECTION N.T.S. SECTION SECTION A -A- N.T.S. N.T.S. . _ ', PLAN -SEEPAGE BED OUTSIDE ROADWAY - - - -- N.T.S. _ .. '. O m v 10 PLAN VIEW CONCRETE COLLAR NON -TRAFFIC AREAS I F - © PERFORATED PVC PIPE, ASTM D-3035 SOP 35 WITH 6 - 3/8" DIA. HOLES AT 3" ON CENTER. O DRAINAGE GEOTE%i1LE, TYPE I (SPWC SECTION 2060). 10 PVC CAP, SOLVENT WELDED OR GASKETED (WATERTIGHT). n (2) q4 REBAR HOOPS WITH H4 VERTICALS. 12 N0. 12 AWG. GALVANIZED FINDER WIRE. 13 THREE 6" DIAMETER COILS. O NOTES: .. I __� - .._ - F- .-- - «° ^° • °.2 °.' �:- �A� WELLS ARE F OR OBSERVATION OF GROUNDWATER LEVEL NEAR STORM DRAINAGE. FACILITIES. .. O O O O -'— "" 3 12" 10 CB)LOCATION OF GROUNDWATER OBSERVATION WELLS SHALL BE APPROVED BY ENGINEER. -. .. .. ..... _ , PLAN VIEW ay WELL SECTION CONCRETE COLLAR — TRAFFIC AREAS PLAN - N.T.S. _ 3 - " PLAN -SEEPAGE BED _. UNDER SIDEWALK SECTION „ N.T.S. CONCRETE COLLAR — — — — - '` 2015 2012 IDAHO STANDARDS FOR PUBLIC WORKS conlsTrzucnoN GROUND WATER OBSERVATION WELL STANDARD DRAWING N SD of 627 IDAHO STANDARDS FOR PUBLIC WORKS CONSTRUCnoN GROUND WATER OBSERVATION WELL STANDARD DRAWING NO. SD 627 J 20f 2VL Property Test Method English Tensile Strength Grab ASTM D-4632 120 Ibs Elongation ASTM D-4632 50% Puncture ASTM D-4833 65 Ibs Trapezoidal Tear Strength ASTM D-4533 50 Ibs UV Resistance Apparent Opening Size AOS ASTM D-4355 ASTM D-4751 70% 70 US Std. Sieve Permittivity ASTM D-4491 1.50 sec-1 Water Flow Rate ASTM D-4491 120 gpm/ft2 Woven Fabric Property Test Method English Tensile Strength Grab ASTM D-4632 Min 250 Ibs Puncture Strength or CBR Puncture ASTM D-4833 or ASTM D-6241 Min 125 Ibs or Min 950 Ibs UV Resistance ASTM D-4355 Min 80% Apparent Opening Size AOS ASTM D-4751 70 US Std. Sieve Water Flow Rate ASTM D-4491 Min 18 m/ft2 Percent Open Area CW-02215 Min 4% GEOTEXT LE REQUIREMENTS NOTES: 1. NONWOVEN OR MONOFILAMENT WOVEN GEOTEXTILES ARE REQUIRED. SLIM FILM OR SLIT TAPE GEOTEXTILES ARE NOT APPROVED FOR DRAINAGE APPLICATIONS. Know what's below. je—uCall before you di NOTE: WORK CONTAINED WITHIN THESE PLANS SHALL NOT COMMENCE UNTIL AN ENCROACHMENT PERMIT AND/OR A GRADING PERMIT HAS BEEN ISSUED. DRAWING STATUS: FOR AGENCY REVIEW SEAL —ENGINEER • PLANNING A BLAINE A. W O M E R • SURVEYING CIVIL CIVIL ENGINEERING ENGINEERING W• PUBLIC WORKS Boise, ID 83706, 4355 W. Emerald Street, Suite 145 • 1-208-593-7555 CITY OF MERIDIAN, ID SEE SHEET WOODCREST TOWNHOMES SUBDIVISION C1.0 STORM WATER IMPROVEMENT PLANS STORM WATER DETAILS SCALE: H V: SHEET NO, C5.1 FILE NO. N1420004 REVISIONS MIN �fE IDIAN— APP OVED, Th— pn h— b f . . . d ro ..11 —d ........... rePon Permit N.— APPENDIX B - CALCULATIONS �fE IDIAN— APP OVED, Th pn h b f . . . d ro ..11 d ........... rePon Permit N.— POST-DEVELOPMENT RUNOFF CALCULATIONS E RI IAN;, APPROVED x Plana Have Men round ro hh lh m. e�nm�.ehhpl coa tleflciencies lountl al inapeglane II naatl to M wrracletl 7pp of lad information on apP�ovatl pi.— any ro.,Thom. am h an Th. wnat—hen a.flm.a,n,h. Mne. Dale: asa ACHD Calculation Sheet for Finding Peak Discharge/Volume - Rational Method worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These s shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. Steps fo thod calculated for post-develo Calculate Post -Development Flows (for pre -development flows, increase number of storage facilities to create new tab) User input in yellow cells. 1 Project Name Woodcrest Subdivision, Basin A 2 Is area drainage basin map provided? YES (map must be included with stormwater calculations) 3 Enter Design Storm (100-Year or 25-Year With 100-Year Flood Route) 100 4 Enter number of storage facilities (25 max) 5 Area of Drainage Subbasin (SF or Acres) SF Acre! 6 Determine the Weighted Runoff Coefficient (C) C=[(C1xA1)+(C2xA2)+(CnxAn)]/A Weighted Avf dirk to Chnw Mnrr Suhhacinc n Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin 1 Subbasin 2 3 4 5 6 7 8 9 10 31,933 4,862 0.84 0.95 0.30 0.86 7 Calculate Overland Flow Time of Concentration in Minutes (Tc) or use default 10 user Calculate min 10 Min. 8 Determine the average rainfall intensity (i) from IDF Curve based on Tc i 2.58 in/hr 9 Calculate the Post -Development peak discharge (QPeak) Qpeak 1.88 cfs 10 Calculate total runoff vol (V) (for sizing primary storage) V 2,523 ft3 V = Ci (Tc=60)Ax3600 11 Calculate Volume of Runoff Reduction Vrr Enter Percentile Storm I (95th percentile = 0.60 in) 95th 0.60 in Enter Runoff Reduction Vol (95th Percentile=0.60-in x Area x C) Vrr 1,577 ft.. 12 Detention: Approved Discharge Rate to Surface Waters (if applicable) cfs 13 Volume Summary Surface Storage: Basin Basin Forebay V 252 ft' Primary Treatment/Storage Basin V 2,270 ft' Subsurface Storage Volume Without Sediment Factor (See BMP 20 Tab) V 2,523 ft' Estimated Runoff Coefficients for Various Surface Type of Surface Runoff Coefficients "( Business Downtown areas 0.70-0.95 Urban neighborhoods 0.50-0.70 Residential Single Family 0.35-0.50 Multi -family 0.60-0.75 Residential (rural) 0.25-0.40 Apartment Dwelling Areas 0.70 Industrial and Commercial Light areas 0.80 Heavy areas 0.90 Parks, Cemeteries 0.10-0.25 Playgrounds 0.20-0.35 Railroad yard areas 0.20-0.40 Unimproved areas 0.10-0.30 Streets Asphalt 0.95 Concrete 0.95 Brick 0.95 Roofs 0.95 Gravel 0.75 Fields: Sandy soil Soil Type Slope A B C D Flat: 0-2% 0.04 0.07 0.11 0. Average: 2-6% 0.09 0.12 0.15 0.. Steep:>6% 0.13 0.18 0.23 0.. Adapted from ASCE Z:\Drawings\N1420004\Reports\Drainage\ACHD_SD_CALCS_112018 Basin A Version 10.5, November 2018 2/1/2022, 5:06 PM E RI IAN;, APPROVED x Plana Have Men hound ro hh lh m. e�nm�.ehhpl coa tleflciencies lountl al inapeglane II naatl to M wrraclatl 7pp of lad information on apP�ovatl pi.— any ro.,Thom. am h an rfl. wnar—rien a.flm.a,n,h. Mne. Dale: asa ACHD Calculation Sheet for Finding Peak Discharge/Volume - Rational Method worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These s shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. Steps fo thod calculated for post-develo Calculate Post -Development Flows (for pre -development flows, increase number of storage facilities to create new tab) User input in yellow cells. 1 Project Name Woodcrest Subdivision, Basin B 2 Is area drainage basin map provided? YES (map must be included with stormwater calculations) 3 Enter Design Storm (100-Year or 25-Year With 100-Year Flood Route) 100 4 Enter number of storage facilities (25 max) 5 Area of Drainage Subbasin (SF or Acres) SF Acre 6 Determine the Weighted Runoff Coefficient (C) C=[(C1xA1)+(C2xA2)+(CnxAn)]/A Weighted Avf Clirk to Chnw Mnrr Suhhacinc n Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin 1 Subbasin 2 3 4 5 6 7 8 9 10 43,057 0.99 0.95 0.95 7 Calculate Overland Flow Time of Concentration in Minutes (Tc) or use default 10 user Calculate min 10 Min. 8 Determine the average rainfall intensity (i) from IDF Curve based on Tc i 2.58 in 9 Calculate the Post -Development peak discharge (QPeak) Qpeak 2.42 cfs 10 Calculate total runoff vol (V) (for sizing primary storage) V 3,245 ft3 V = Ci (Tc=60)Ax3600 11 Calculate Volume of Runoff Reduction Vrr Enter Percentile Storm I (95th percentile = 0.60 in) 95th 0.60 in Enter Runoff Reduction Vol (95th Percentile=0.60-in x Area x C) Vrr 2,028 ft. 12 Detention: Approved Discharge Rate to Surface Waters (if applicable) cfs 13 Volume Summary Surface Storage: Basin Basin Forebay V 325 ft' Primary Treatment/Storage Basin V 2,921 ft' Subsurface Storage Volume Without Sediment Factor (See BMP 20 Tab) V 3,245 ft' Estimated Runoff Coefficients for Various Surface Type of Surface Runoff Coefficients "( Business Downtown areas 0.70-0.95 Urban neighborhoods 0.50-0.70 Residential Single Family 0.35-0.50 Multi -family 0.60-0.75 Residential (rural) 0.25-0.40 Apartment Dwelling Areas 0.70 Industrial and Commercial Light areas 0.80 Heavy areas 0.90 Parks, Cemeteries 0.10-0.25 Playgrounds 0.20-0.35 Railroad yard areas 0.20-0.40 Unimproved areas 0.10-0.30 Streets Asphalt 0.95 Concrete 0.95 Brick 0.95 Roofs 0.95 Gravel 0.75 Fields: Sandy soil Soil Type Slope A B C D Flat: 0-2% 0.04 0.07 0.11 0. Average: 2-6% 0.09 0.12 0.15 0.. Steep:>6% 0.13 0.18 0.23 0.. Adapted from ASCE Z:\Drawings\N1420004\Reports\Drainage\ACHD_SD_CALCS_112018 Basin B Version 10.5, November 2018 2/1/2022, 4:39 PM �fE IDIAN— APP OVED, Th— pn h— b f . . . d ro ..11 —d ........... rePon Permit N.— RETENTION POND CALCULATIONS �E IDIZ IAN;', APPROVED se pn here Men round b wltn .npilwm. e�nm�p .... coda tl•flciencies lountl al inapecdane II naatl ro t wrraclatl rapartlly off pi. information on h. apP�ovd Dlerel�lnclwl n9 any wmp•da.•m a m. dm.wm•wm• Dab: `NOTE: T s we as Permit Number. ry agy. ACHD Calculation Sheet for Sizing Basins rksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these order to be accepted. User input in yellow cells. 1 Project Name Woodcrest Subdivision, Basin A tnter numoer oT tsasins Iv max) L 3 Number of Cells (Forebay+primary=2, Primary Only-1) 1 4 Design Storm 100 Link to:[Qv 5 Weighted Runoff Coefficient C 0.86 QV TR55 6 Area A (Acres) 0.84 acres 7 Approved Discharge Rate (if applicable) 0.00 cfs 8 1-Basin Forebay V 2,523 ft3 Toggle between Forebay and Primary Basin, enter data and print for each st s4e z sae shF z sik Shp. Fbw Flay; Flory A X; plv W Sihs.et 3i S < L + Mile Shp 2 �L-.� hp.. _ Forebay _ 9 Select Forebay Shape 5-Irregular 10 Width of Forebay Bottom W 0.0 ft 11 Length of Forebay Bottom L 0.0 ft 12 Side Slopes(H:1) H:1 100.00 13 Enter Bottom Elevation 0.00 ft 14 Enter Top Bank Elevation 3.00 ft 15 Enter Water Surface Elevation (WSE) 2.75 ft 16 Distance Between Forebay and Primary Basin (blank if na) 0.00 ft 17 Enter Elevation Berm 0.00 ft 18 Enter High Groundwater Elevation 0.00 ft 19 Min. Freeboard Requirement 0.50 20 Freeboard Provided 21 Infiltration Area for Forebay Infiltration? 8.00 in/hr Note: infiltration required if Design Infiltration Rate, Enter 0 for no infiltration bottom sloped%or0 outflow 22 Infiltration Area for Forebay As M 75 ftz Enter 0 for no infiltration 23 I Storm Duration I i total Q Runoff Vol Perc Vol Pre-Dev I Total I Max Vol I Discharge Discharge Reqd Min Hr I in/hr I cfs I ft' I ft3I ft, 1 ft31 ft, 50 1 0 1 50 Saved Stage (ft) New Stage (ft) Side Slope (H:V) Basin Width at Stage (ft) Basin Length at Stage (ft) Surface Area A at Stage (ft) Saved Surface Area A at Stage (ft) Surface Area A at Stage (ft) OVERIDE Volume Below Stage (ft) 0.00 100.000 0.0 0.0 Override 458.00 0 0.50 100.000 0.0 0.0 Override 604.00 1.00 100.000 0.0 0.0 Override 764.00 1.50 100.000 0.0 0.0 Override 938.00 2.00 100.000 0.0 0.0 Override 1126.00 2.50 100.000 0.0 0.0 Override 1328.00 3.00 100.000 0.0 0.0 Override 1545.00 2,881 3.00 ft depth for storage 25 Does Forebay have capacity? 26 Time to drain forebay 90%volume in 48-hours minimum 45.4 hours STORAGE OK Z:\Drawings\N1420004\Reports\Drainage\ACHD_SD_CALCS_11201S Basin A 2/1/2022, 5:06 PM Version 10.0, May 2018 �fE IDIAN— APP OVED, Th— pn h— b f . . . d ro ..11 —d ........... rePon Permit N.— SEEPAGE BED CALCULATIONS �E IDR IAN;, APPROVED x Dlana bee Men /ppntl ro M In auMbnMl complknu wlitl appllude bulking cotlae. Cotle MMlancix lountl at lnexallane will xM k b wrractatl N Ia or the Iniwmatlon on epproratl pbna. Tlie 'DrkNW^plWing.ny ACHD Calculation Sheet for Sizing Seepage Bed With Optional Chambers ;.gpl�tlkMpn�n;" n tl. at a. tlm. d InaxpM�.°tlp Date: NOTE: Ttis worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's Permit Number. rvaauro flat n methodology. These calculations shall establish a minimum requirement. The Engineers methodology must result in facilities that meet or exceed these calculations in order to be accepted. Note this spreadsheet pulls information from the "Peak Q,V" tab Calculate Post -Development Flows (for pre -development flows, increase number of storage facilities to create new tab) User input in yellow cells. 1 Project Name Woodcrest Subdivision, Basin B 2 Enter number of Seepage Beds (25 max) 3 Design Storm 4 Weighted Runoff Coefficient C 5 Area A (Acres) 6 Approved discharge rate (if applicable) 7 Is Seepage Bed in Common Lot? No V 8 Set Total Design Width of All Drain Rock W 9 Set Total Design Depth of All Drain Rock D Rock Only, Do Not Include Filter Sand Depth or Cover 10 Void Ratio of Drain Rock Voids 0.4 for 1.5"-2" drain rock and 3/4" Chips 11 Design Infiltration Rate (8 in/hr max) Perc 12 Size of WQ Perf Pipe (Perf 1800) Dia pipe 13 Size of Overflow Perf Pipe (Perfs 360°), READ if Q100>3.3 cfs 14 Calculate Total Storage per Foot Spf 15 Calculate Design Length L Override Value Required for Chambers 16 Variable Infiltration Window L SWL 17 Variable Infiltration Window W SWW 18 Time to Drain 90%volume in 48-hours minimum 19 Length of WC, & Overflow Perf Pipes 20 Perf Pipe Checks. Qperf >= Qpeak; where Qperf=CdxAxV(2xgxH) 1 100 0.95 0.99 acres 0.00 cfs 4,057 10.0 ft 4.6 ft 0.4 Unkto: LQV QV TR55 — ft3 25%Sediment 8.00 in/hr 18 in in 25.2 ft3/ft 161 ft 161 ft 10.0 ft 3.4 hours 161 ft Optional Storage Chambers Note: This assumes chambers are organized in a rectangular layout. 1-StormTech, 1 Type of Chambers SC740 2 Volume to Store V 0 ft3 3 Installed Chamber Width Cw 4.25 ft Installed Chamber Depth Cd 2.50 ft Installed Chamber Height Ch 7.12 ft 4 Chamber Void Factor 5 Chamber Storage Volume, Without Rock, Per Manuf 45.90 ft'/Unit 6 Chamber Storage Volume, With Rock, Per Manuf 74.90 ft'/Unit 7 Total Number of Units Required 0 ea 8 Area of Infiltration Aperc ftz 9 Volume Infiltration Vperc 0 ft3/hr 10 Time to Drain hours 90%volume in 48-hours minimum Z:\Drawings\N1420004\Reports\Drainage\ACHD_ SD_CALCS_112018 Basin B Version 10.0, May 2018 2/1/2022, 4:39 PM �fE IDIAN— APP OVED, Th— pn h— b f . . . d ro ..11 —d ........... rePon Permit N.— SAND AND GREASE TRAP CALCULATIONS �E miAx— APPROVED x Plana Mx Men—d b � IIInMlcomplk.. wIth ppllwWe bulking C. Code deficiancI. bond at InexN.e II need to M.rrecbd gardlaee I. blwmatlon on Ith. ped Dlaml�bclWb9 any wrath. ACHD Calculation Sheet for Sand/Grease Traps oa N.tlm.aln. pMne. e�e: Permit Number: rvamaao+oN )TE This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. User input in yellow cells. 1 Project Name Woodcrest Subdivision, Basin A Enter number of Sand/Grease Traps (25 max) 1 Reference for Throat widths (inch) ADS Boise Lar-ken WQU, Vault BMP 16 1000 G 48.0 50.5 n/a 1500 G 60.0 61.5 n/a WQU1000 n/a n/a 60 WQU1500 n/a n/a 60 Number of Peak Flow Baffle Throat Velocity Is the Vault Size S/G Traps Q-cfs Spacing width Area (ftZ) 0.5 fps Velocity (inch) (inch) max. ok? 1000 G 1 1.88 20 48 6.67 0.28 Z:\Drawings\N1420004\Reports\Drainage\ACHD_SD_CALCS_112018 Basin A 2/1/2022, 5:06 PM Version 10.0, May 2018 �E miAx— APPROVED x Plana Mx Men—d b � IIInMlcomplk.. wIth ppllwWe bulking C. Code deficiancI. bond at InexN.e II need to M.rrecbd gardlaee I. blwmatlon on Ith. ped Dlaml�bclWb9 any wrath. ACHD Calculation Sheet for Sand/Grease Traps oa N.tlm.aln. pMne. e�e: Permit Number: rvamaao+oN )TE This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. User input in yellow cells. 1 Project Name Woodcrest Subdivision, Basin B Enter number of Sand/Grease Traps (25 max) 1 Reference for Throat widths (inch) ADS Boise Lar-ken WQU, Vault BMP 16 1000 G 48.0 50.5 n/a 1500 G 60.0 61.5 n/a WQU1000 n/a n/a 60 WQU1500 n/a n/a 60 Number of Peak Flow Baffle Throat Velocity Is the Vault Size S/G Traps Q-cfs Spacing width Area (ftZ) 0.5 fps Velocity (inch) (inch) max. ok? 1000 G 1 2.42 20 48 6.67 0.36 Z:\Drawings\N1420004\Reports\Drainage\ACHD_SD_CALCS_112018 Basin B 2/1/2022, 4:39 PM Version 10.0, May 2018 �fE IDIAN— APP OVED, Th— pn h— b f . . . d ro ..11 —d ........... rePon Permit N.— INLET, GUTTER AND PIPE CALCULATIONS Clfe I- APPROVED se plans 1a °m:en el Report eieflow E ress Extension for Autodesk®Civil 3D® by Autodesk, Inc. Permit Numb<r. ry 0o crest Subdivision: Pond Outlet A Circular Diameter (ft) = 1.00 Invert Elev (ft) = 100.00 Slope (%) = 1.00 N-Value = 0.012 Calculations Compute by: Known Q Known Q (cfs) = 1.88 101.50 101.00 100.50 100.00 99.50 1 Thursday, Feb 3 2022 Highlighted Depth (ft) = 0.50 Q (cfs) = 1.880 Area (sqft) = 0.39 Velocity (ft/s) = 4.76 Wetted Perim (ft) = 1.57 Crit Depth, Yc (ft) = 0.59 Top Width (ft) = 1.00 EGL (ft) = 0.85 Section 2 Depth (ft) .00 1.50 1.00 0.50 1 11 -0.50 3 Reach (ft) Clfe I- APPROVED se plans 1a °m:en el Report eieflow E ress Extension for Autodesk®Civil 3D® by Autodesk, Inc. Permit Numb<r. ry 0o crest: Rolled Curb A Gutter Cross SI, Sx (ft/ft) = 0.020 Cross SI, Sw (ft/ft) = 0.062 Gutter Width (ft) = 1.50 Invert Elev (ft) = 100.00 Slope (%) = 0.40 N-Value = 0.012 Calculations Compute by: Known Q Known Q (cfs) = 1.88 Elev (ft) 101.00 100.75 100.50 100.25 100.00 99.75 0 Section 5 10 15 20 Reach (ft) Highlighted Depth (ft) Q (cfs) Area (sqft) Velocity (ft/s) Wetted Perim (ft) Crit Depth, Yc (ft) Spread Width (ft) EGL (ft) 25 M Thursday, Feb 3 2022 = 0.25 = 1.880 = 0.92 = 2.04 = 9.60 = 0.27 = 9.35 = 0.31 Depth (ft) 1.00 0.75 0.50 0.25 MIN -0.25 35 �E ID$ IAN__ APPROVED t eport aram.ema nome�i.a io�.ammaD.aio�a n -aaa m a w—i.a earal.aa Duna marmaw o. aDProvea Dlana Inclualn9 any reg fro;; dreflow E ress Extension for Autodesk® Civil MOD by Autodesk, Inc. oaar rb. rim. m maP.�ae�a. r.: Permit Number m 0o crest: Inlet A Grate Inlet Location Curb Length (ft) Throat Height (in) Grate Area (sqft) Grate Width (ft) Grate Length (ft) Gutter Slope, Sw (ft/ft) Slope, Sx (ft/ft) Local Depr (in) Gutter Width (ft) Gutter Slope (%) Gutter n-value AI I o f m en sl o n s i n ft = Sag _ -0- _ -0- = 2.63 = 1.50 = 2.00 = 0.072 = 0.020 _ -0- = 1.50 _ -0- _ -0- 0.3 Calculations Compute by: Q (cfs) Highlighted Q Total (cfs) Q Capt (cfs) Q Bypass (cfs) Depth at Inlet (in) Efficiency (%) Gutter Spread (ft) Gutter Vel (ft/s) Bypass Spread (ft) Bypass Depth (in) Thursday, Feb 3 2022 Known Q = 1.88 = 1.88 = 1.88 _ -0- = 3.65 = 100 = 11.32 _ -0- _ -0- _ -0- �E ID$ IAN__ APPROVED t eport aram.ema nome�i.a io�.ammaD.aio�a n -aaa m a w—i.a earal.aa Duna marmaw o. aDProvea Dlana Inclualn9 any reg fro;; dreflow E ress Extension for Autodesk® Civil MOD by Autodesk, Inc. oaar rb. rim. m maP.�ae�a. r.: Permit Number m 0o crest: Inlet B Grate Inlet Location Curb Length (ft) Throat Height (in) Grate Area (sqft) Grate Width (ft) Grate Length (ft) Gutter Slope, Sw (ft/ft) Slope, Sx (ft/ft) Local Depr (in) Gutter Width (ft) Gutter Slope (%) Gutter n-value AI I o f m en sl o n s i n ft = Sag _ -0- _ -0- = 2.63 = 1.50 = 2.00 = 0.072 = 0.020 _ -0- = 1.50 _ -0- _ -0- Calculations Compute by: Q (cfs) Highlighted Q Total (cfs) Q Capt (cfs) Q Bypass (cfs) Depth at Inlet (in) Efficiency (%) Gutter Spread (ft) Gutter Vel (ft/s) Bypass Spread (ft) Bypass Depth (in) Thursday, Feb 3 2022 Known Q = 2.42 = 2.42 = 2.42 _ -0- = 4.20 = 100 = 13.62 _ -0- _ -0- _ -0- �fE IDIAN— APP OVED, Th— pn h— b f . . . d ro ..11 —d ........... rePon Permit N.— APPENDIX C - GEOTECHNICAL ENGINEERING AND ADDITIONAL INFORMATION (.�,1rE APIDIAN PROVED a n :.coons appro etl pla slain re .r Date: specions. Permit Number: m GEOTECHNICAL I ENVIRONMENTAL MATERIALS TESTING I SPECIAL INSPECTION AN EMPLOYEE -OWNED COMPANY September 24, 2021 Don Newell Landmark Pacific Development, Inc. P.O. Box 1939 Eagle, Idaho 83616 ashton.homes(a?hotmail.com RE: Geotechnical Evaluation Woodcrest Townhomes Subdivision 1789 North Hickory Way Meridian, Idaho ALLWEST Project No. 521-095G Mr. Newell: ALLWEST has completed the authorized geotechnical evaluation for the proposed Woodcrest Townhomes Subdivision development planned at the above address in Meridian, Idaho. The purpose of this evaluation was to characterize subsurface soil conditions at the site and provide geotechnical recommendations to assist planning, design, and construction of the proposed development. Based on our evaluation, the site is suitable forthe planned development. The attached report presents the results of ourfield evaluation, laboratory testing, and our recommendations. We appreciate the opportunity to be of service to Landmark Pacific. If you have any questions or need additional information, please contact us at (208) 895-7898. Sincerely, ALLWEST Adrian Mascorro, P.E. rIeN If,�lzYy2� a�� Anish Pathak, E.I. Area Manager Staff Engineer 255 N. Linder Rd., Suite #100, Meridian, ID 83642 Phone: 208.895.7898 • Fax: 208.898.3959 Hayden, ID • Lewiston, ID • Meridian, ID • Spokane Valley, WA • Missoula, MT www.allwesttesting.com ( 1(E IDIAh- APPROVED Permit Number: m GEOTECHNICAL EVALUATION WOODCREST TOWNHOMES SUBDIVISION MERIDIAN, IDAHO ALLWEST PROJECT NO. 521-095G September 24, 2021 Prepared for: Landmark Pacific Development, Inc. P.O. Box 1939 Eagle, Idaho 83616 Prepared By: ALLWEST 255 North Linder Road, Suite 100 Meridian, Idaho 83642 ALLWEST WWW.ALLWESTTESTING.COM CAE roiAN- APPROVED x Pl . Mx Men bend b nMl complknce wIth appIi Mlking C. Code MeciencI. bond at In.p.Nan. Il nW to M co.mcbd gardl... of IM blwmatlon on aDPr pp DIa p1b., Wb9 any .Dmd.a. ro � on ttl. can.tmntlan atN.tlm.ain.xnMn.. P.- Permit Number: m TABLE OF CONTENTS ALLWEST Project No. 521-095G Woodcrest Townhomes Subdivision Meridian, Idaho Page 1.0 SCOPE OF SERVICES........................................................................................ 2 2.0 PROJECT UNDERSTANDING/ PROPOSED CONSTRUCTION ......................... 2 3.0 FIELD EVALUATION PROCEDURES................................................................. 3 4.0 SITE CONDITIONS.............................................................................................. 3 4.1 General Geologic Conditions............................................................................. 3 4.2 General Soil Conditions..................................................................................... 4 5.0 EXPLORATION AND SAMPLING....................................................................... 4 5.1 Subsurface Soil Conditions............................................................................... 4 5.2 Subsurface Water.............................................................................................. 4 6.0 LABORATORY TESTING.................................................................................... 5 7.0 CONCLUSIONS AND RECOMMENDATIONS.................................................... 5 7.1 Grading and Drainage....................................................................................... 5 7.2 Site Preparation................................................................................................. 5 7.3 Subgrade Stabilization...................................................................................... 6 7.4 Excavation......................................................................................................... 7 7.5 Materials............................................................................................................ 7 7.6 Fill Placement and Compaction......................................................................... 8 7.7 Utility Trenches.................................................................................................. 9 7.8 Wet Weather Construction................................................................................ 9 7.9 Cold Weather Construction............................................................................... 9 7.10 Stormwater Disposal..................................................................................... 10 7.11 Asphalt Pavements....................................................................................... 10 7.12 Foundation Recommendations...................................................................... 11 7.12.1 Shallow Foundation Design............................................................... 11 7.12.2 Concrete Slabs-On-Grade................................................................. 12 8.0 ADDITIONAL RECOMMENDED SERVICES ..................................................... 12 9.0 EVALUATION LIMITATIONS............................................................................. 13 Appendix A - Site Vicinity Map, Exploration Location Plan Appendix B - Test Pit Logs, Unified Soil Classification System Appendix C - Laboratory Test Results 1-001- GEOTECHNICAL I ENVIRONMENTAL ALLWESTMATERIALS TESTING I SPECIAL INSPECTION AN EMPLOYEE -OWNED COMPANY CVIE MAN — APPROVED e. pi,�. ne.e eeee m..a to Rio ea <o ,ana p.a�o�e report Date: n� of �oewot�ooe. Permit Number. m Geotechnical Evaluation Woodcrest Townhomes Subdivision Meridian, Idaho ALLWEST has completed the geotechnical evaluation for the proposed Woodcrest Townhomes Subdivision development planned at 1789 North Hickory Way in Meridian, Idaho. The general location of the site is shown on Figure A-1 — Site Vicinity Map in Appendix A of this report. The purpose of this evaluation was to identify subsurface soil conditions at the site, and provide opinions and recommendations for the proposed development, relative to earthwork, stormwater disposal, asphalt pavement section design, and foundation construction. This report details the results of our field evaluation and presents recommendations to assist development. 1.0 SCOPE OF SERVICES Our scope of services for the project included the following- 1) Prior to subsurface exploration, we visited the site to observe site accessibility and to pre -mark exploration locations, as required by Idaho Digline. 2) Notified Idaho Digline to locate on -site utilities, as required by Idaho state law. 3) Subcontracted a backhoe and operator to observe the excavation of 7 test pits throughout the site. 4) Visually described, classified, and logged the soils encountered within test pits and we obtained soil samples within select test pits. 5) Performed seepage tests within select test pits to evaluate subsurface seepage and installed a PVC pipe within 3 test pits for future groundwater monitoring. 6) Performed laboratory tests on select soil samples to assess some of the soil engineering properties and characteristics. 7) Reviewed the results of the field evaluation and laboratory testing, performed engineering analyses, and prepared this report with field and laboratory results, subsurface logs, and geotechnical-related opinions and recommendations. We provided our services for the project in general accordance with our geotechnical proposal (521-095P) dated March 1, 2021. 2.0 PROJECT UNDERSTANDING/ PROPOSED CONSTRUCTION Based on electronic communication with you on February 18, 2021, which included a Site Layout 12 (no date) by Blaine A. Womer and architectural elevation drawings for Fairway Townhomes (4-unit) (dated December 28, 2020) by ogos Architecture, we understand plans consist of developing an approximate 2-acre site with seven two- story townhome buildings, with each building containing either two, three, or four livable units. The development will contain associated infrastructure, stormwater disposal GEOTECHNICAL I ENVIRONMENTAL ALLWESTMATERIALS TESTING I SPECIAL INSPECTION AN EMPLOYEE -OWNED COMPANY C E MAN — APPROVED e. pi,�. ne.e eeee m..a I Rio ea <o �an.epBa�o�e pon Date: n� of �eew�t�oee. Permit Number. m Geotechnical Evaluation ALLWEST Project No. 521-095G Woodcrest Townhomes Subdivision Page 3 Meridian, Idaho facilities, and an asphalt -paved roadway and access -lane. We assume the buildings will be supported on conventional shallow foundations, with garages consisting of slab - on -grade construction. Site grading plans are not available at the time of this report, but we anticipate final site grades will remain similar to existing grades, with expected cut and fill for the site to be 2 feet or less for foundation construction. We assume that no below -grade construction (i.e., basements) will occur as part of the development. Note, that by authorizing ALLWEST to provide this geotechnical evaluation for residential townhome construction, you are also authorizing ALLWEST to provide follow-up construction observation and monitoring during earthwork construction. These services will be provided on a time -and -expense basis, and are beyond the scope of services in this evaluation. If we are not retained to provide these follow-up services, we cannot be held responsible for earthwork -related errors or omissions during earthwork construction, or potential subsequent poor concrete performance. 3.0 FIELD EVALUATION PROCEDURES To complete this evaluation, on March 5, 2021, we observed the excavation of 7 test pits to maximum depths of 9 to 13 feet; depths varied due to soil caving within select test pits. We identified subsurface soil conditions, logged the subsurface soil profiles, and obtained soil samples for laboratory testing. We performed field seepage testing within three test pits to help evaluate subsurface soil seepage. At completion of exploration, the test pits were loosely backfilled with excavated soil approximately level with existing ground surfaces. Approximate test pit locations are shown on Figure A-2 — Exploration Location Plan in Appendix A. 4.0 SITE CONDITIONS At the time of exploration, the site consisted of undeveloped land with native vegetation, and trees along the north boundary. The overall site is bordered by North Hickory Way to the north, a mix of residential buildings and undeveloped farmland to the west, and commercial properties to the south and east. 4.1 General Geologic Conditions The geologic conditions at the site are mapped as Gravel of Whitney Terrace (Qwg) on the "Geologic Map of the Boise Valley and Adjoining Area, Western Snake River Plain, Idaho" (by Othberg and Stanford, 1992). Soils consist of sandy pebble and cobble gravel up to 16 to 80 feet thick, mantled by 3 to 6 feet of loess. The soils encountered in test pits are generally consistent with geologic mapping. ALLWEST GEOTECHNICAL I ENVIRONMENTAL MATERIALS TESTING I SPECIAL INSPECTION AN EMPLOYEE -OWNED COMPANY CVIE MAN — APPROVED e. pi,�. ne.e eeee m..a I Rio ea <o �an.epBa�o�e pon Date: n� of �eew�t�oee. Permit Number. m Geotechnical Evaluation Woodcrest Townhomes Subdivision Meridian, Idaho 4.2 General Soil Conditions ALLWEST Project No. 521-095G Page 4 The USDA Natural Resources Conservation Service (NRCS), which represents the upper 5 feet of soil profile, has mapped the soils on the site as Purdam silt loam. The parent materials are mixed alluvium, lacustrine deposits, and/or loess consisting of silt loam, silty clay loam, cemented material, and stratified sand to loam. The soils encountered in test pits are generally consistent with NRCS mapping. 5.0 EXPLORATION AND SAMPLING We observed the excavation of test pits with a Case 580C backhoe with a 3-foot-wide bucket. We visually described the soils encountered within test pits referencing ASTM D 2488, which utilizes the Unified Soil Classification System (USCS), and we obtained soil samples at select depths for further identification and laboratory testing. We performed seepage testing within three test pits on site. The test pit locations were identified on -site with white -flagged stakes or white PVC pipes. We obtained Google Earth latitude and longitude coordinates of test pit locations with a hand-held cellular device. These coordinates can be found on individual test pit logs in Appendix B and should be considered accurate to the degree implied by the method used. 5.1 Subsurface Soil Conditions At the time of exploration, the site contained approximately 3 inches of surficial roots and vegetation at the ground surface. We observed trees along the north boundary of the site; large tree roots may be encountered between 2 and 4 feet below ground. In general, subsurface soils within the observed test pits consisted of surficial native lean clays or sandy silts, underlain by silts or sandy silts with varying amounts and thicknesses of induration and/or cementation, overlying gravels and sands with depth. Detailed soil descriptions, depths, and notes are presented on individual test pit logs in Appendix B. The descriptive soil terms used on the test pit logs in this report, can be referenced by the USCS. A copy of the USCS is included in Appendix B. Subsurface conditions may vary between exploration locations. Such changes in subsurface conditions may not be apparent until construction, and if they change significantly from those observed, then accordingly, construction timing, plans, and costs may change. 5.2 Subsurface Water At the time of exploration, we did not encounter groundwater within test pits down to a maximum depth of 13 feet. Groundwater in the area is typically influenced by local irrigation and nearby canals, drains, and laterals. Groundwater may also be influenced by precipitation, on -site construction, and development to adjacent sites. Subsurface water will fluctuate throughout the different seasons of the year, but will most likely be affected during seasonal snow melt and irrigation seasons (March to October). We GEOTECHNICAL I ENVIRONMENTAL ALLWESTMATERIALS TESTING I SPECIAL INSPECTION AN EMPLOYEE -OWNED COMPANY CVIE MAN — APPROVED e. pi,�. ne.e eeee m..a I Rio ea <o �an.epBa�o�e pon Date: n� of �eew�t�oee. Permit Number. m Geotechnical Evaluation ALLWEST Project No. 521-095G Woodcrest Townhomes Subdivision Page 5 Meridian, Idaho recommend monitoring be accomplished to verify the presence or absence of seasonal high groundwater throughout the site, to assist civil stormwater disposal design. We installed PVC pipes within 3 test pits throughout the site for future groundwater monitoring. ALLWEST can perform monthly groundwater monitoring, if requested. 6.0 LABORATORY TESTING We performed laboratory testing to supplement field classifications and to assess some of the soil engineering properties and parameters. The laboratory tests conducted included moisture content (ASTM D 2216), gradation (ASTM D 1140), Atterberg limits (ASTM D 4318), and California bearing ratio (CBR) (ASTM D 1883). Laboratory test results are summarized in Appendix C, and are also presented on test pit logs in Appendix B, where applicable. 7.0 CONCLUSIONS AND RECOMMENDATIONS Based on our observations, testing, and evaluation, in our opinion the site is suitable for the planned residential development, provided our recommendations are adhered to. The following recommendations are presented to assist with planning, design, and construction of the development, relative to earthwork, infrastructure, stormwater disposal, asphalt pavement section design, and shallow foundation construction. These recommendations are based on our understanding of the proposed development, the conditions observed within exploration locations, laboratory test results, and engineering analysis. If the scope of construction changes, or if conditions are encountered during construction that differ from those described herein, we should be notified so we can review our recommendations and provide revisions, if necessary. 7.1 Grading and Drainage We did not review final grading plans for this development, but we anticipate site grading will consist of cuts and fills of up to 2 feet or less. We should be notified if actual site grading varies significantly from this stated information, as it may affect our recommendations herein. Final site grades should be such that final ground surfaces slope away at 5% for 5 feet from foundations and any other development areas. 7.2 Site Preparation Prior to conducting site grading, surficial soil containing vegetation, roots and organics should be removed below proposed site grading fill areas, pavement areas, foundation areas, and any other development areas. In general, we anticipate approximately 3 inches of site stripping will be required for majority of the site to remove surficial vegetation and roots. GEOTECHNICAL I ENVIRONMENTAL ALLWESTMATERIALS TESTING I SPECIAL INSPECTION AN EMPLOYEE -OWNED COMPANY CVIE MAN — APPROVED e. pi,�. ne.e eeee m..a I Rio ea <o �an.epBa�o�e pon Date: n� of �eew�t�oee. Permit Number. m Geotechnical Evaluation Woodcrest Townhomes Subdivision Meridian, Idaho ALLWEST Project No. 521-095G Page 6 • Where trees are encountered and will be removed as part of the development, large root systems should be completely over -excavated and replaced with suitable fill soils. Tree roots depths will not fully be known until construction, but we anticipate a minimum of 2 to 4 feet of over -excavation will be required to remove tree roots. • Loose test pit backfill will settle with time, so where any test pits are located below proposed structures or any development areas, the loose test pit backfill soil must be re -excavated its entire depth and replaced with suitably moisture - conditioned and compacted fill soils. Existing over -excavated soils can be reused to backfill the test pits, provided the soils are not overly saturated, and they can achieve the required compaction criteria (as required in section 7.6 Fill Placement and Compaction). Test pit locations are identified in the field with white -flagged stakes or with white PVC pipes. We recommend test pit areas be accurately surveyed so that they may be located and remediated, prior to earthwork construction and development. • After site stripping, over -excavations, loose test pit remediation, and prior to site grading, utility backfill, roadway construction, foundation construction, or any other type of development, the exposed subgrades should be proof -rolled with a minimum of 5-ton vibratory roller, with loaded dump trucks, with loaded front- end loaders, or with a vibratory hoe -pack, to confirm subgrade stability. This will also assist in identifying any soft subgrade areas. If native subgrades are observed to significantly deflect or pump, the subgrades should be over - excavated and replaced with properly compacted fills or stabilized as recommended in section 7.3 Subgrade Stabilization. 7.3 Subgrade Stabilization If the subgrade soils are observed to pump or deflect significantly during grading, the subgrades should be stabilized prior to fill placement. Subgrades may be stabilized using geosynthetic reinforcement in conjunction with imported granular structural fill. The required thicknesses of granular structural fill (used in conjunction with geosynthetic reinforcement) will be dependent on the construction traffic loading, which is unknown at this time. Therefore, a certain degree of trial and error may be required during construction to verify recommended stabilization section thicknesses. Geosynthetic reinforcement should consist of Tensar TX-160 or equivalent. Alternatives to Tensar TX-160 must be approved by the geotechnical engineer prior to use on site. The following recommendations are provided for subgrade stabilization using geosynthetic reinforcement. • Geosynthetic reinforcement materials should be placed on a non -disturbed subgrade with smooth surface. Loose and disturbed soil should be removed prior to placement of geosynthetic reinforcement materials. GEOTECHNICAL I ENVIRONMENTAL ALLWESTMATERIALS TESTING I SPECIAL INSPECTION AN EMPLOYEE -OWNED COMPANY CVIE MAN — APPROVED e. pi,�. ne.e eeee m..a I Rio ea <o �an.epBa�o�e pon Date: n� of �eew�t�oee. Permit Number. m Geotechnical Evaluation Woodcrest Townhomes Subdivision Meridian, Idaho ALLWEST Project No. 521-095G Page 7 A minimum weight 4-ounce, non -woven filter fabric should be placed on the undisturbed subgrade. The geosynthetic reinforcement should be placed directly on top of the filter fabric. The filter fabric and geosynthetic reinforcement should be unrolled in the primary direction of fill placement and should be over- lapped at least 3 feet, or follow manufacturer's recommendations. • The geosynthetic materials should be pulled taut to remove slack. Construction equipment should not be operated directly on the geosynthetic materials. Fill should be placed from outside the excavation to create a pad to operate equipment on. We recommend a minimum of 12 to 18 inches of granular structural fill be placed over the geosynthetic reinforcement before operating construction equipment on the fill. Low pressure, track -mounted equipment should be used to place fill over the geosynthetic reinforcement. • Granular structural fill placed directly over geosynthetic reinforcement should be properly moisture -conditioned prior to placement, and once placed, be statically rolled. This section is the "bridge" section over soft subgrades. • After the first "bridge" lift has been placed, the remaining fill material above the "bridge" section should be compacted to structural fill criteria in section 7.6 Fill Placement and Compaction, utilizing vibratory compaction methods. • Vibration should be discontinued if it reduces the subgrade stability. If compaction criterion is not met within the fill lift above the "bridge" section, the "bridge" section thickness is not enough, and subgrade stabilization must be attempted again with a greater "bridge" section. The geotechnical engineer or a representative of the geotechnical engineer must be on -site during subgrade stabilization to verify our recommendations are followed, and to provide additional recommendations, as needed. 7.4 Excavation Excavation of on -site soil can be accomplished with typical excavation equipment. We recommend excavations greater than 4 feet deep be sloped no steeper than 1.5H:1V (horizontal to vertical). Alternatively, deeper excavations may be shored or braced in accordance with Occupational Safety and Health Administration (OSHA) specifications and local codes. Regarding trench wall support, the site soil is considered Type C soil according to OSHA guidelines. Ultimately, the contractor is responsible for site safety, excavation configurations and following OSHA guidelines. 7.5 Materials Stripped soils containing vegetation or debris are only suitable for use in non-structural landscape areas. Existing on -site soils may be reused as site grading fill, provided they are stockpiled separately, they meet the criteria below, and they are moisture- GEOTECHNICAL I ENVIRONMENTAL ALLWESTMATERIALS TESTING I SPECIAL INSPECTION AN EMPLOYEE -OWNED COMPANY C E MAN — APPROVED e. pi,�. ne.e eeee m..a I Rio ea <o �an.epBa�o�e pon Date: n� of �eew�t�oee. Permit Number. m Geotechnical Evaluation ALLWEST Project No. 521-095G Woodcrest Townhomes Subdivision Page 8 Meridian, Idaho conditioned and compacted as required in this report. Imported granular soils should be free of organics, debris, and other deleterious material and meet the following criteria. Import materials should be approved by ALLWEST prior to delivery to the site. Fill Type Criteria Site Grading Fill Maximum size <_ 6 inches; ° Retained on % inch sieve < 30° ; Liquid limit < 50 /o Maximum size <_ 6 inches; Granular Structural Fill, Retained on 3/4-inch sieve < 30%; Granular Subbase Passing No. 200 sieve <_ 15%; Non -plastic Alternatively, meet ISPWC section 801 6 inches max Maximum size <_ 1 inch; Crushed Base Course Retained on 3/4-inch sieve < 10%; Passing No. 200 sieve < 10%; Non -plastic Alternatively, meet ISPWC section 802 (Type Maximum size <_ 2 inches; Utility Trench Backfill Retained on 3/4-inch sieve <°30%; Passing No. 200 sieve <_ 10 /°; Non -plastic Alternatively, meet ISPWC section 305 (Type I 7.6 Fill Placement and Compaction Fill should be placed in lift thicknesses which are appropriate for the compaction equipment used. Typically, 8- to 12-inch-thick loose -lifts are appropriate for typical rubber -tire and steel -drum compaction equipment. Lift thicknesses should be reduced to 4 inches for hand -operated compaction equipment. Fill should be moisture - conditioned to within 2 percentage points of the optimum moisture content prior to placement to facilitate compaction. Fill should be compacted to the following percentages of the maximum dry density as determined by ASTM D 1557 (modified Proctor). For roadway and utility trench construction only, the local governing jurisdiction may provide their own method of determining the maximum dry density and compaction requirements (including subgrade). Fill Area TCompaction (0 X-�� Sub rade' Proof-rol12 Site Grading Fill / Granular Structural Fill 95 Granular Subbase / Crushed Base Course 952 Utility Trench Backfill 922 'Subgrade stability must be verified and approved by a representative of the geotechnical engineer prior to any fill placement or construction. 2For roadway and utility trench construction only, the local governing jurisdiction may provide their own method of determining the maximum dry density and compaction requirements (including subgrade). ALLWEST GEOTECHNICAL I ENVIRONMENTAL MATERIALS TESTING I SPECIAL INSPECTION AN EMPLOYEE -OWNED COMPANY C E MAN — APPROVED e. pi... n..e eeee m..a t. Rio ea <o Cana pBa�o�e p.n Date: n� of �.ew.t�o.e. Permit Number. m Geotechnical Evaluation Woodcrest Townhomes Subdivision Meridian, Idaho 7.7 Utility Trenches ALLWEST Project No. 521-095G Page 9 Support soils for underground utilities will most likely consist of sandy lean clays, sandy silts, and/or gravels with silt and sand. These soils should provide adequate support for utilities, provided utility subgrades are compacted utilizing vibratory methods, such as with a large vibratory hoe -pack. If utility pipe subgrades are soft, yielding, and/or saturated at the time of construction, subgrade over -excavation and replacement with competent structural fill may be required below utilities. If support soils yield and/or are saturated at the time of construction, we should be notified to observe these soils and provide additional recommendations, as necessary. We strongly recommend backfilling trench excavations with fill soils which meet criteria in section 7.5 Materials, as on -site fine-grained soils (silts and clays) may be difficult to moisture -condition and compact in utility trenches. 7.8 Wet Weather Construction We recommend earthwork for this site be scheduled for the drier seasons of the year. If construction is undertaken in wet periods of the year, it will be important to slope the ground surface to provide drainage away from construction. If construction occurs during or immediately after excessive precipitation, it may be necessary to over - excavate and replace saturated subgrade soil, which might otherwise be suitable. The on -site soils are sensitive to disturbance when wet. If these soils become wet and unstable, we recommend construction traffic is minimized where these soils are exposed. Low ground -pressure (tracked) equipment should be used to minimize disturbance. Soft and disturbed subgrade areas should be excavated to undisturbed soil and backfilled with structural fill, compacted to requirements stated in this report. In addition, it should be noted the on -site soils tend to have notable adhesion when wet and may be easily transported off -site by construction traffic. 7.9 Cold Weather Construction The on -site soils are frost susceptible. If site grading and construction are anticipated during cold weather, we recommend good winter construction practices be observed. Snow and ice should be removed from excavated and fill areas prior to additional earthwork or construction. Pavement, flatwork, and foundation portions of the construction should not be placed on frozen ground, nor should the supporting soils be permitted to freeze during or after construction. Frozen soils must not be used as fill. If native subgrades, or suitably moisture -conditioned and compacted fill lifts, will be left exposed to freezing temperatures overnight, those areas should be protected with a minimum of 12 inches of loose soil, or covered with heated construction blankets, so construction subgrades do not freeze. Any frozen soils should be removed prior to additional fill placement or construction of any kind. GEOTECHNICAL I ENVIRONMENTAL ALLWESTMATERIALS TESTING I SPECIAL INSPECTION AN EMPLOYEE -OWNED COMPANY CVIE MAN — APPROVED e. pi... n..e eeee m..a t. Rio ea <o Cana pBa�o�e p.n Date: n� of �.ew.t�o.e. Permit Number. m Geotechnical Evaluation ALLWEST Project No. 521-095G Woodcrest Townhomes Subdivision Page 10 Meridian, Idaho Earthwork construction during cold inclement weather will require a higher level of attention and detail to achieve required construction and compaction criteria, and may lead to additional earthwork requirements and extended construction schedules. 7.10 Stormwater Disposal During our field investigation we performed field seepage testing within test pits TP-1, TP-3, and TP-5, where we noted field -measured seepage rates of greater than 15 inches per hour (in/hr) within poorly -graded gravel with silt and sand, and greater than 30 in/hr within poorly -graded gravel with sand. Due to our field observations and the variability of indurated and cemented soils, we do not recommend stormwater disposal occur within or above sandy silt soils, as indurated and cemented soils will exhibit very poor and inconsistent soil seepage. Based on our field evaluation, the following allowable seepage rate should be utilized for on -site stormwater disposal into poorly -graded gravel with silt and sand or poorly - grade gravel with sand. Poorly -graded gravel with sand (with or without silt) ..................... 8 in/hr Stormwater disposal facilities should be constructed a minimum of 1 foot into the receiving. Seepage beds should be "burrito wrapped" or otherwise maintain a separation/filter fabric between native fine-grained soils and drain rock/filter sand to help prevent fine soil migration into drainable/filtering media. During construction, ALLWEST should observe stormwater disposal facility subgrades to establish if the suitable receiving soil is encountered and to ensure the separation/filter fabric has been properly installed. The proper separation from bottom of stormwater disposal facilities and seasonal high groundwater should be maintained. At the time of exploration, we did not observe groundwater within the test pits. Groundwater monitoring should be accomplished within the installed PVC pipes on -site to verify the presence or absence of groundwater. We installed slotted a PVC pipes within 3 test pits on -site for future groundwater monitoring. These pipes should be monitored monthly or biweekly during seasonal snow melt and irrigation seasons (March to October) to confirm the seasonal high groundwater elevations throughout the site. 7.11 Asphalt Pavements Prior to pavement section construction, the pavement subgrade should be proof -rolled as recommended in section 7.2 Site Preparation (or as recommended by local jurisdictions). Local roadways should be designed for a 20-year Equivalent Single Axle Load (ESAL) of 33,000, which is equivalent to a traffic index (TI) of 6. If actual traffic conditions are different than what is stated, we should be notified so that we may modify our pavement section design. GEOTECHNICAL I ENVIRONMENTAL ALLWESTMATERIALS TESTING I SPECIAL INSPECTION AN EMPLOYEE -OWNED COMPANY CVIE MAN — APPROVED e. pi... n..e eeee m..a t. Rio ea <o �an.epBa�o�e p.n Date: n� of �.ew.t�o.e. Permit Number. m Geotechnical Evaluation ALLWEST Project No. 521-095G Woodcrest Townhomes Subdivision Page 11 Meridian, Idaho Based on existing site grades, the roadway subgrade will consist of sandy lean clay or sandy silt soils. We performed CBR testing on a sandy silt soil to evaluate pavement section design, where we obtained a CBR of 24.7. However, based on our experience with lean clays and the variability of subgrade soils, we recommend a CBR of 12 be used for pavement section design, which is equivalent to an R-value of 30. The following flexible asphalt pavement section design is provided adhering to the Idaho Transportation Department (ITD), which utilizes the AASHTO pavement design methodology. Based on subgrade preparation requirements, design assumptions, and frost -depth requirements, we recommend the following pavement section be utilized for subdivision roadway construction for local roadways. Asphalt Crushed Granular Pavement Application Concrete Base Course Subbase inches inches inches Local Roadway 2.5 4 9 Base course and subbase should conform to the material recommendations as noted in this report and should be placed over a properly prepared subgrade. The subgrade, subbase, and base course surfaces should slope at no less than 2% away from the crown of the roadway to help reduce the potential for surface water infiltration into the underlying pavement subgrade. Asphalt concrete pavement should be compacted to minimum of 92% of the Rice density. Crack maintenance on pavements should be performed at a minimum of every 3 years, or when cracking is evident. Crack sealing will help reduce surface water infiltration into the supporting soils. 7.12 Foundation Recommendations The following recommendations should be utilized to design and construct proposed shallow foundations. 7.12.1 Shallow Foundation Design For frost protection, footings should be embedded at least 24 inches below the lowest adjacent grade. Spread footings should be supported entirely on a minimum of 1 foot of granular structural fill over existing native subgrades. Granular structural fill should extend a minimum of 6 inches beyond sides of footings. Prior to placing concrete, ALLWEST should observe all footing excavations to verify that our recommendations are being followed. Foundation subgrade soils should be probed and approved by ALLWEST, prior to placement of granular structural fill. ALLWEST GEOTECHNICAL I ENVIRONMENTAL MATERIALS TESTING I SPECIAL INSPECTION AN EMPLOYEE -OWNED COMPANY CVIE MAN — APPROVED e. pi... n..e eeee m..a t. Rio ea <o �an.epBa�o�e p.n Date: n� of �.ew.t�o.e. Permit Number. m Geotechnical Evaluation Woodcrest Townhomes Subdivision Meridian, Idaho ALLWEST Project No. 521-095G Page 12 • After the subgrade has been observed and approved, the placed granular structural fill should be tested for suitable moisture content and compaction (as required in section 7.6 Fill Placement and Compaction) prior to concrete placement. • If the subgrades are approved and granular structural fill meets compaction criteria, footings may be designed for the following bearing pressure: Allowable Bearing Minimum Granular Subgrade Type Pressure Structural Fill Thickness (psf) below Footing feet Native Silts or Clays 2,500 1 The net allowable bearing pressure value may be increased by 1/3 to account for transient loads such as wind and seismic. • If the previous recommendations are implemented, it is our opinion total settlement will be approximately less than 1 inch and differential settlement will be approximately less than '/z of an inch. • A coefficient of friction of 0.40 may be used for sliding resistance between concrete footings and native soils, and 0.45 may be used for sliding resistance between concrete footings and imported granular structural fill. 7.12.2 Concrete Slabs -On -Grade We recommend placing a minimum of 6 inches of crushed base course immediately below slabs and flatwork. Subgrades within these areas should be prepared as indicated in Section 7.2 Site Preparation of this report. Base course should be compacted as recommended in Section 7.5 Fill Placement and Compaction. We recommend consideration be given to including a moisture vapor retarder beneath concrete slab -on -grade floors to retard moisture migration through the slabs if moisture -sensitive floor coverings are planned. We recommend the moisture retarder be installed per American Concrete Institute (ACI) recommendations and specifications. To protect slabs from moisture migration which may impact flooring performance, it is important to include the moisture vapor retarder as well as directing surface and subsurface water away from the slabs. In addition, concrete should have adequate time to cure prior to placing impermeable flooring. 8.0 ADDITIONAL RECOMMENDED SERVICES By authorizing ALLWEST to provide this evaluation, you are also authorizing us to provide observations and testing throughout construction. As an independent testing company, ALLWEST can document the recommendations included in this report are ALLWEST GEOTECHNICAL I ENVIRONMENTAL MATERIALS TESTING I SPECIAL INSPECTION AN EMPLOYEE -OWNED COMPANY CVIE MAN — APPROVED e. pi,�. ne.e eeee m..a I Rio ea <o Cana pBa�o�e pon Date: n� of �eew�t�oee. Permit Number. m Geotechnical Evaluation ALLWEST Project No. 521-095G Woodcrest Townhomes Subdivision Page 13 Meridian, Idaho properly implemented, provide quality control testing, and observe earthwork for conformance to project specifications. As a minimum, we recommend the following testing and observations be provided by ALLWEST: • Observe site stripping, any over -excavations, compaction of test pit backfill, and any other soil backfills. • Observe subgrade proof -rolling and approve subgrades prior to fill construction, materials placement, and construction of any kind. • Observe removal of disturbed soil and subgrade stabilization, if required. • Conduct compaction testing of fill for general site grading, utilities, pavement areas, and foundation/slab areas. • Observe placement of/test asphalt for compaction, oil content and gradation. If we are not retained to provide the recommended construction observation and testing services, we shall not be responsible for soil engineering -related construction errors or omissions. 9.0 EVALUATION LIMITATIONS This report has been prepared to assist planning, design, and construction of the proposed Woodcrest Townhomes Subdivision in Meridian, Idaho. Our services consist of professional opinions and conclusions made in accordance with generally accepted geotechnical engineering principles and practices in our local area at the time this report was prepared. This acknowledgement is in lieu of all warranties either expressed or implied. The following plates complete this report: Appendix A — Site Vicinity Map, Exploration Location Plan Appendix B — Test Pit Logs, Unified Soil Classification System Appendix C — Laboratory Test Results ALLWEST GEOTECHNICAL I ENVIRONMENTAL MATERIALS TESTING I SPECIAL INSPECTION AN EMPLOYEE -OWNED COMPANY �fE IDIAN— APP OVED, Th— pn h— b f . . . d ro ..11 —d ........... rePon Permit N.— Appendix A A-1 — Site Vicinity Map A-2 — Exploration Location Plan ALLWEBT ftftftm=OWWI-' r^ E UII stick -Rd Edgar Ct . f -e Addeseni&- I ~, E Bald \m'St� E Sto E K'ama D �• G� E Sedgewic-O`�_ --Y -E-Cougar-Creek A ? Z� a4 E �`oo fldolvv Challis-D �Leslie'Dr-lgrass St. c ' ipz E*BI6e•HerorrSt iv CU c C EaFnes t ' VNIX .■ •I' '�III��I��I� - arty E Carol St '� •\ _ J x a V7 wi Ir• !�'z`'' s �- ® • ``�!' �-- - -E-Fairview Ave Ir pm M PI ■ ,.: I:.: f t WdsomL-n ' :ar E-1evve11-St-�^; V. LL Y e - 6 " =-Was ;ngtoA—D" _ a. ��tLL�. a' Qa o t*• E Gar•�Ite A� a J T �' r Cn ice: o � E�State^Aver .� • � , s. ,;r . .r I -- � � ° j .� {er�— r-° r E COnimerclaI St Al A L Bill lB r Z rjSt o-- f t Atla•St rne -- z'—E-L-anark-St emu �m i r ' _ < E-FE3ra kliFlgRdJ= - `° �- Gpogle_ Ea th shy p . �.a 1 S ring vood Dr 4000 ft 20�1�° Da'e^ ne ri e° napec°° a Pe It Nu ber: � I - I D00' JTVIES CASEVENt �----• I � I I Legend p Approximate location of test pit observed by ALLWEST. Slotted PVC pipe installed in test pit. s ® inn C)i Figure A-2 - Exploration Location Plan Geotechnical Evaluation ALLWEST Woodcrest Townhomes Subdivision Meridian, Idaho 255 N. Linder Road, Suite 100 Client: Landmark Pacific Development, Inc. Meridian, Idaho 83642 Project No.- 521-095G Phone: (208) 895-7898 Fax: (208) 898-3959 Date: September 2021 �fE IDIAN— APP OVED, Th— pn h— b f . . . d ro ..11 —d ........... rePon Permit N.— Appendix B Test Pit Logs Unified Soil Classification System (USCS) ALLWEBT ftftftM=OWWI-' E IDIAN APPROV Tlese plans M1av ° ga°afeae atup'M1M rela 91a requareU�, aeo Date: omrs Permit N—m ° '°""°" ALLWEST DATE STARTED: 3/5/2021 TP - 1 MERIDIAN, IDAHO DATE FINISHED: 3/5/2021 EXCAVATOR: CASE 580C OPERATOR: Steve Just EXCAVATION METHOD:3-ft wide test pit tling any GEOTECHNICAL SECTION COMPANY: Just Dig'It Exc. ons" ^ LOGGER:Anish Pathak TEST PIT LOG WEATHER: Sunny 521-095G NOTES: See Figure A-2 in Appendix A for approximate test pit location. Woodcrest Townhomes Subdivision LATITUDE (DEGREES): N 43°37'16.068" (43.62113°) 0 LONGITUDE (DEGREES): W-116°21'49.7916" (-116.363831 °) 0 a � U) TOTAL DEPTH: 13' U = SAMPLE w Z a o DESCRIPTION NOTES Sandy Lean CLAY (Native); brown, stiff, moist bigniticant roots and vegetation observed o inches. 1 CL 2 SILT; brown, medium dense, moist 3 MIL ... moderate induration observed throughout soil profile Passing No. 200 sieve = 86% BG Moisture content = 12% 4 Sandy SILT; tan, medium dense to very dense, moist 5 ... moderate induration observed from 4 to 6 feet 6 ML 7 ... strong cementation observed from 6 to 8-1/2 feet 8- Poorly-graded GRAVEL with silt, sand and cobbles; tan, medium dense, moist _ 9 0 GP -GM ° O 1 0 O 1 Poorly -graded GRAVEL with sand; tan, medium dense, moist o(� O 1 GP D (� Field seepage test performed at 12 feet. Field seepage rate = >30 in/hr. O o� 1 Test pit terminated at 13 feet. Slotted PVC pipe installed to 13 feet. 1 WATER LEVELS V WHILE EXCAVATING Y AT COMPLETION t AFTER EXCAVATING Sheet 1 of 1 CMEIZIDIAN APPROV Tlesepal^a'� a ag ,a°eem °ed'== ALLWEST DATE STARTED: 3/5/2021 TP - 2 ,ae" DATE FINISHED: 3/5/2021 EXCAVATOR: CASE 580C MERIDIAN, IDAHO OPERATOR: Steve Just EXCAVATION METHOD: 3-ft wide test pit aDProveE Dlam� GEOTECHNICAL SECTION COMPANY: Just Dig'It Exc. a . IPle conaV LOGGER:Anish Pathak Permit Numbs tNu, TEST PIT LOG WEATHER: Sunny QWQ 521-095G Woodcrest Townhomes Subdivision NOTES: See Figure A-2 in Appendix A for approximate test pit location. LATITUDE (DEGREES): N 43°37'15.1608" (43.620878°) O LONGITUDE (DEGREES): W-116°21'49.1292" (-116.363647°) 0 a to u) TOTAL DEPTH: 10' U = SAMPLE w Z a o DESCRIPTION NOTES Sandy Lean CLAY (Native); brown, stiff, moist bigniticant roots and vegetation observed o inches. CL 1 Sandy SILT; tan, medium dense to very dense, moist 2 ... moderate induration observed from 1-1/2 to 3 feet 3 MIL 4 ... strong cementation observed from 3 to 5 feet 5 Poorly -graded GRAVEL with silt and sand; tan, medium dense, moist ° 6 0 0 O 7 o GP -GM OU $ o O 9 o O o 10— Test pit terminated at 10 feet due to caving. 1 1 1 1 WATER LEVELS V WHILE EXCAVATING Y AT COMPLETION t AFTER EXCAVATING Sheet 1 of 1 E IDIAN APPROV Tlese plans M1av ° ga°afeae atuermp'M1M rela 91a requareU�, Eao Date:N r PittNumbs ° '°""°m ALLWEST DATE STARTED: 3/5/2021 TP - 3 MERIDIAN, IDAHO DATE FINISHED: 3/5/2021 EXCAVATOR: CASE 580C OPERATOR: Steve Just EXCAVATION METHOD:3-ft wide test pit tling any GEOTECHNICAL SECTION COMPANY: Just Dig'It Exc. onaV ^ LOGGER:Anish Pathak TEST PIT LOG WEATHER: Sunny 521-095G NOTES: See Figure A-2 in Appendix A for approximate test pit location. Woodcrest Townhomes Subdivision LATITUDE (DEGREES): N 43°37'15.1104" (43.620864°) 0 LONGITUDE (DEGREES): W-116°21'47.6316" (-116.363231 °) 0 a � TOTAL DEPTH: 13' U = SAMPLE w Z a DESCRIPTION NOTES Sandy Lean CLAY (Native); brown, stiff, moist bigniticant roots and vegetation o serve o inches. Passing No. 200 sieve = 66% BG Moisture content = 23% 1 CI- ILL = 33, PL = 23, PI = 10 2 Sandy SILT; tan, medium dense to dense, moist 3 MIL ... moderate induration observed throughout soil profile Passing No. 200 sieve = 66% BG Moisture content = 15% 4 5 Poorly -graded GRAVEL with silt, sand and cobbles; tan, medium dense, moist ° O 6 O 7 Field seepage test performed at 7 feet. " Field seepage rate = >15 in/hr. GP -GM ° 8 O 9 OU ° O 1 ° O Poorly -graded GRAVEL with sand; tan, medium dense, moist 0 1 0 O GP 1 O O O O 1 Test pit terminated at 13 feet. Slotted PVC pipe installed to 13 feet. 1 WATER LEVELS V WHILE EXCAVATING Y AT COMPLETION t AFTER EXCAVATING Sheet 1 of 1 CMEIZIDIAN APPROV Tlesepal^a'� a ag ,a°eem °ed'== ALLWEST DATE STARTED: 3/5/2021 TP - 4 ,ae" DATE FINISHED: 3/5/2021 EXCAVATOR: CASE 580C MERIDIAN, IDAHO OPERATOR: Steve Just EXCAVATION METHOD: 3-ft wide test pit aDProveE Dlam� GEOTECHNICAL SECTION COMPANY: Just Dig'It Exc. a . IPle conaV LOGGER:Anish Pathak Permit Numbs tNu, TEST PIT LOG WEATHER: Sunny QWQ 521-095G Woodcrest Townhomes Subdivision NOTES: See Figure A-2 in Appendix A for approximate test pit location. LATITUDE (DEGREES): N 43°37'14.0196" (43.620561 °) O LONGITUDE (DEGREES): W-116°21'47.43" (-116.363175°) 0 a to U) TOTAL DEPTH: 9' U = SAMPLE w Z) a o DESCRIPTION NOTES Sandy SILT (Native); brown, medium dense to dense, moist ign- scan roo s and vegetation observed o inches. 1 Passing No. 200 sieve = 65% BK ILL = 32, PL = 28, PI = 4 MIL CBR = 24.7 2 ... moderate induration observed from 2 to 3-1/2 feet 3 Poorly -graded GRAVEL with silt and sand; tan, medium dense, moist ° 4 O OU O 5 o 6 OU 0 GP -GM O 7 o O 8 0 O 0 O L 9 Test pit terminated at 9 feet due to caving. 1 1 1 1 1 WATER LEVELS V WHILE EXCAVATING Y AT COMPLETION t AFTER EXCAVATING Sheet 1 of 1 CMEIZIDIAN APPROV Tlesepal^a'� a ag ,a°eem °ed'== ALLWEST DATE STARTED: 3/5/2021 TP -5 ,ae" DATE FINISHED: 3/5/2021 EXCAVATOR: CASE 580C MERIDIAN, IDAHO OPERATOR: Steve Just EXCAVATION METHOD: 3-ft wide test pit aDProveE Dlam� GEOTECHNICAL SECTION COMPANY: Just Dig'It Exc. a . IPle conaV LOGGER:Anish Pathak Permit Numbs tNu, TEST PIT LOG WEATHER: Sunny QWQ 521-095G Woodcrest Townhomes Subdivision NOTES: See Figure A-2 in Appendix A for approximate test pit location. LATITUDE (DEGREES): N 43°37'14.3256" (43.620646°) O LONGITUDE (DEGREES): W-116°21'50.1372" (-116.363927°) 0 a to U) TOTAL DEPTH: 9' U = SAMPLE w Z) a o DESCRIPTION NOTES Sandy SILT (Native); brown to light tan, medium dense to dense, ign- scan roo s and vegetation observed o moist inches. 1 2 BG 3 MIL ... moderate induration observed from 2 to 5 feet 4 5 ... moderate cementation observed from 5 to 6-1/2 feet 6- Poorly-graded GRAVEL with silt and sand; tan, medium dense, moist 7 0 GP -GM 0 O 8 o Field seepage test performed at 8-1/2 feet. GP Poorly -graded GRAVEL with sand; tan, medium dense, moist o Field seepage rate = >30 in/hr. 9 Test pit terminated at 9 feet due to caving. 1 1 1 1 1 WATER LEVELS V WHILE EXCAVATING Y AT COMPLETION t AFTER EXCAVATING Sheet 1 of 1 E IDIAN APPROV Tlese plans M1av ° ga°afeae atuermp'M1M rela 91a requareU�, Eao Date:N r PittNumbs ° '°""°m ALLWEST DATE STARTED: 3/5/2021 TP - 6 MERIDIAN, IDAHO DATE FINISHED: 3/5/2021 EXCAVATOR: CASE 580C OPERATOR: Steve Just EXCAVATION METHOD:3-ft wide test pit tling any GEOTECHNICAL SECTION COMPANY: Just Dig'It Exc. onaV ^ LOGGER:Anish Pathak TEST PIT LOG WEATHER: Sunny 521-095G NOTES: See Figure A-2 in Appendix A for approximate test pit location. Woodcrest Townhomes Subdivision LATITUDE (DEGREES): N 43°37'14.4336" (43.620676°) 0 LONGITUDE (DEGREES): W-116°21'51.8076" (-116.364391 °) 0 a � U) TOTAL DEPTH: 10' U = SAMPLE w Z a o DESCRIPTION NOTES Sandy SILT (Native); brown, medium dense, moist igni scan roo s and vegetation observed o inches. 1 ML 2 SILT; brown, dense, moist 3 MIL ... moderate induration observed throughout soil profile 4 Sandy SILT; light tan, medium dense to dense, moist ... moderate induration observed from 4 to 5-1/2 feet 5 MIL 6 ... weak cementation observed from 5-1/2 to 7 feet 7 Poorly -graded GRAVEL with silt and sand; tan, medium dense, moist ° O GP -GM U a 9 O 0 O 10— Test pit terminated at 10 feet. 1 1 1 1 WATER LEVELS V WHILE EXCAVATING Y AT COMPLETION t AFTER EXCAVATING Sheet 1 of 1 CMEIZIDIAN APPROV Tlesepal^a'� a ag ,a°eem °ed'== ALLWEST DATE STARTED: 3/5/2021 TP - 7 ,ae" DATE FINISHED: 3/5/2021 EXCAVATOR: CASE 580C MERIDIAN, IDAHO OPERATOR: Steve Just EXCAVATION METHOD: 3-ft wide test pit aDProveE Dlam� GEOTECHNICAL SECTION COMPANY: Just Dig'It Exc. a . IPle conaV LOGGER:Anish Pathak Permit Numbs tNu, TEST PIT LOG WEATHER: Sunny QWQ 521-095G Woodcrest Townhomes Subdivision NOTES: See Figure A-2 in Appendix A for approximate test pit location. LATITUDE (DEGREES): N 43°37'13.3428" (43.620373°) O LONGITUDE (DEGREES): W-116°21'50.688" (-116.36408°) 0 a to u) TOTAL DEPTH: 10' U = SAMPLE w Z) a o DESCRIPTION NOTES Sandy SILT (Native); brown to light tan, medium dense, moist igni scan roo s and vegetation observed o inches. 1 2— MIL 3 4 Poorly -graded GRAVEL with silt and sand; tan, medium dense, moist o 5 a,�< o� GP -GM 6 o i 0 O 7 Poorly -graded GRAVEL with sand and cobbles; tan, medium dense, moist ° 0 O 8- - GP 0 O o� 9 0 O o� 0 10— Test pit terminated at 10 feet due to caving. Slotted PVC pipe installed to 10 feet. 1 1 1 1 WATER LEVELS V WHILE EXCAVATING Y AT COMPLETION t AFTER EXCAVATING Sheet 1 of 1 CVIE MAN — APPROVED e. pi,�. ne.e ce.e m..a to Rio ea <o ,ana poa�o�e report Date: n� of �oewot�ooe. Permit Number. m Unified Soil Classification System MAJOR DIVISIONS SYMBOL TYPICAL NAMES GW Well -Graded Gravel, CLEAN Gravel -Sand Mixtures. GP Poorly -Graded Gravel, GRAVELS Gravel -Sand Mixtures. GRAVELS Silty Gravel, GRAVELS GM Gravel -Sand -Silt Mixtures. COARSE WITH FINES Clayey Gravel, GRAINED GC Gravel -Sand -Clay Mixtures. SOILS Well -Graded Sand, CLEAN SW Gravelly Sand. SANDS SP Poorly -Graded Sand, SANDS Gravelly Sand. SM Silty Sand, SANDS Sand -Silt Mixtures. WITH FINES Sc Clayey Sand, Sand -Clay Mixtures. MIL Inorganic Silt, SILTS AND CLAYS Silt or Clayey Fine Sand. Inorganic Clay of Low to LIQUID LIMIT CL Medium Plasticity, LESS THAN 50°/O Sand or Silt Clay. OL Organic Silt and Clay of Low FINE Plasticity. GRAINED SOILS Inorganic Silt, Elastic Silt, MH Micaceous Silt, SILTS AND CLAYS Fine Sand or Silt. CH Inorganic Clay of High Plasticity, LIQUID LIMIT GREATER THAN 50% Fat Clay. OH Organic Clay of Medium to High Plasticity. Highly Organic Soils PT Peat, Muck and Other Highly Organic Soils. ALLWEST �fE IDIAN— APP OVED, Th— pn h— b f . . . d ro ..11 —d ........... rePon ft Permit N.— Appendix C Laboratory Test Results ALLWEST ftftftm=OWWI-' Summary of Laboratory Test Results ,,m.o,......... ^ "IT epth (Feet) Moisture Content M Gradation Atterberg Limits CBR Sample Classification (USCS) Liquid Limit M Plasticity Index M No. Gravel M Sand M Silt/Clay M 1 3'/z -4 12 14 86 SILT ML 3 '/2 - 1 23 34 66 33 10 Sandy Lean CLAY CL 3 3'/2 -4 15 34 66 Sandy SILT ML 4 1 - 2 - 35 65 32 4 24.7 Sandy SILT ML Table C-1 255 N. Linder Road, Suite 100 • Meridian, Idaho 83642 - (208) 895-7895 • Fax (208) 898-3959 www.allwesttesting.com This report may not be reproduced, except in full, without the permission of ALLWEST. (-�,1rE IDIAN— AP PROVED .PP ro eJ Pla slam requ Date: vu soeci�ons. 60 50 11 U 30 20 10 LIQUID AND PLASTIC LIMITS TEST REPORT Dashed line indicates the approximate upper limit boundary for natural soils ' , , , , , 0 ' O % 0 G CL-ML �ML or OL MH or OH 0 0 lU zu Ju 4U bU bU /u bu W "I UU 1lU LIQUID LIMIT MATERIAL DESCRIPTION ILL PL PI %<#40 %<#200 USCS Sandy Lean Clay 33 23 10 -- 66% CL Sandy Silt 32 28 4 -- 65% ML Project No. 521-095G Client: Landmark Pacific Development, Inc. Project: Woodcrest Townhomes Subdivision *Location: TP-3 Depth: 0.5'-1' ■Location: TP-4 Depth: F-2' ALLWEST Tested By: C. Downes Checked By: J. Varozza Fiaure GI 0tp' IDIAN— APPROVED °; California Bearing Ratio `IB'—pl-� e -°v ASTM D 1883 e reewmo n oa,e' Prc ect: Woodcrest Townhomes Subdivision Project No.. 521-095G Glk Permit N mbar: nt: Landmark Pacific Development, Inc. Location: TP-4 @ 1 - 2 ft Date Tested: 4/12/21 Compaction Method: ASTM D1557 Tested By: C. Downes Classification: Sandy Silt (ML) 500 450 400 350 .N Q' 300 c 0 2 a 250 c 0 200 150 100 50 0 0 0.1 0.2 0.3 0.4 0.5 Penetration (inches) CBR @ 0.1 Inch Penetration: 24.7 Swell (%): 0.5 Dry Unit Weight Before Soak (pcf): 94.0 Water Content Before Soak (%): 19.3 Water Content After Soak, Top 1 Inch (%): 27.8 Surcharge (psf): 50 Immersion Period (hrs): 96 Reviewed By: James Varozza Maximum Dry Unit Weight (pcf): 104.7 Optimum Water Content (%): 17 Remold of Max. Dry Unt Wgt (%): 90 Figure: C-2 ALLWEST 255 N Linder Rd, Suite 100 - Meridian, ID 83642 - (208) 895-7898 - Fax (208) 898-3959 www. a I Iwe sttest i n g. co m This report shall not be reproduced except in full without the permission of ALLW EST. OV E IDIAN— APPROVED ze plans erve Men loene b wm with . e�nm�e moa... coa aoo�.na.e ioo.emm:wouon. �esa,oaw,m��.d la .PProvee Plarelnclutl n9 any , —ro�wnh...W.n onetmtlon o,N.bm.ain,p. bane. te: Permit Number: m DA United States = Department of Agriculture MRCS Natural Resources Conservation Service A product of the National Cooperative Soil Survey, a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local participants Custom Soil Resource Report for Ada County, Idaho -__ r 'IT01:1�r& F JI. ix F ' � = 1 January 31, 2022 CAE miAN- APPROVED x Dlana Mx Men bond b nMl complknce wIth appIi Hiking.dae. Code daflciancI. bond at InexN.e Il need to M.-d gardlaee I. blwmatlon on aDPr pp Dlapll�bclWk9 any w repmd, are requlrM b M on the conetmctlon at Ne gme of inaxctlona. Permit Number: m Preface Soil surveys contain information that affects land use planning in survey areas. They highlight soil limitations that affect various land uses and provide information about the properties of the soils in the survey areas. Soil surveys are designed for many different users, including farmers, ranchers, foresters, agronomists, urban planners, community officials, engineers, developers, builders, and home buyers. Also, conservationists, teachers, students, and specialists in recreation, waste disposal, and pollution control can use the surveys to help them understand, protect, or enhance the environment. Various land use regulations of Federal, State, and local governments may impose special restrictions on land use or land treatment. Soil surveys identify soil properties that are used in making various land use or land treatment decisions. The information is intended to help the land users identify and reduce the effects of soil limitations on various land uses. The landowner or user is responsible for identifying and complying with existing laws and regulations. Although soil survey information can be used for general farm, local, and wider area planning, onsite investigation is needed to supplement this information in some cases. Examples include soil quality assessments (http://www.nres.usda.gov/wps/ portal/nres/main/soils/health/) and certain conservation and engineering applications. For more detailed information, contact your local USDA Service Center (https://offices.sc.egov.usda.gov/locator/app?agency=nres) or your NRCS State Soil Scientist (http://www.nres.usda.gov/wps/portal/nres/detail/soils/contactus/? cid=nres142p2_053951). Great differences in soil properties can occur within short distances. Some soils are seasonally wet or subject to flooding. Some are too unstable to be used as a foundation for buildings or roads. Clayey or wet soils are poorly suited to use as septic tank absorption fields. A high water table makes a soil poorly suited to basements or underground installations. The National Cooperative Soil Survey is a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local agencies. The Natural Resources Conservation Service (NRCS) has leadership for the Federal part of the National Cooperative Soil Survey. Information about soils is updated periodically. Updated information is available through the NRCS Web Soil Survey, the site for official soil survey information. The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or a part of an individual's income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) Persons with disabilities who require �fE IDEZ IAN— APPROVED se plans have Men—dro omvnap« wdn ding cpdez es lopatl atiazpegionz II n'eetl'lo fth A ptl gartllaz non approved Dlansl.lnclutling any w reponz, ere �equired to M on the conavuclion me of Inspections. Permit Number: ry alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA's TARGET Center at (202) 720-2600 (voice and TDD). To file a complaint of discrimination, write to USDA, Director, Office of Civil Rights, 1400 Independence Avenue, S.W., Washington, D.C. 20250-9410 or call (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity provider and employer. 3 1 (E IDIAN- APPROVED Permit Number: m Contents Preface............................................................................ How Soil Surveys Are Made ......................................... SoilMap.......................................................................... SoilMap....................................................................... Legend......................................................................... MapUnit Legend.......................................................... Map Unit Descriptions.................................................. Ada County, Idaho .................................................... 141—Purdam silt loam, 0 to 2 percent slopes...... References..................................................................... ....................................... 2 ....................................... 5 ....................................... 8 .......................................9 .....................................10 ..................................... 11 ......................................11 ..................................... 13 .....................................13 .....................................15 0 CAE miAN- APPROVED x Dlana Mx Men bond b nMl complknce wIth appIi Hiking.dae. Code daflciancI. bond at InexN.e Il need to M.-d gardlaee I. blwmatlon on aDPr pp Dlapll�bclWk9 any w repmd, are requlrM b M on the conetmctlon at Ne gme of inaxctlona. P- Permit Number: m How Soil Surveys Are Made Soil surveys are made to provide information about the soils and miscellaneous areas in a specific area. They include a description of the soils and miscellaneous areas and their location on the landscape and tables that show soil properties and limitations affecting various uses. Soil scientists observed the steepness, length, and shape of the slopes; the general pattern of drainage; the kinds of crops and native plants; and the kinds of bedrock. They observed and described many soil profiles. A soil profile is the sequence of natural layers, or horizons, in a soil. The profile extends from the surface down into the unconsolidated material in which the soil formed or from the surface down to bedrock. The unconsolidated material is devoid of roots and other living organisms and has not been changed by other biological activity. Currently, soils are mapped according to the boundaries of major land resource areas (MLRAs). MLRAs are geographically associated land resource units that share common characteristics related to physiography, geology, climate, water resources, soils, biological resources, and land uses (USDA, 2006). Soil survey areas typically consist of parts of one or more MLRA. The soils and miscellaneous areas in a survey area occur in an orderly pattern that is related to the geology, landforms, relief, climate, and natural vegetation of the area. Each kind of soil and miscellaneous area is associated with a particular kind of landform or with a segment of the landform. By observing the soils and miscellaneous areas in the survey area and relating their position to specific segments of the landform, a soil scientist develops a concept, or model, of how they were formed. Thus, during mapping, this model enables the soil scientist to predict with a considerable degree of accuracy the kind of soil or miscellaneous area at a specific location on the landscape. Commonly, individual soils on the landscape merge into one another as their characteristics gradually change. To construct an accurate soil map, however, soil scientists must determine the boundaries between the soils. They can observe only a limited number of soil profiles. Nevertheless, these observations, supplemented by an understanding of the soil -vegetation -landscape relationship, are sufficient to verify predictions of the kinds of soil in an area and to determine the boundaries. Soil scientists recorded the characteristics of the soil profiles that they studied. They noted soil color, texture, size and shape of soil aggregates, kind and amount of rock fragments, distribution of plant roots, reaction, and other features that enable them to identify soils. After describing the soils in the survey area and determining their properties, the soil scientists assigned the soils to taxonomic classes (units). Taxonomic classes are concepts. Each taxonomic class has a set of soil characteristics with precisely defined limits. The classes are used as a basis for comparison to classify soils systematically. Soil taxonomy, the system of taxonomic classification used in the United States, is based mainly on the kind and character of soil properties and the arrangement of horizons within the profile. After the soil 5 CAE roiAx- APPROVED x Dlana Mx Men bond b nMl complknce wIth appIi Hiking C. Code d0tiI. bond at InexNane Il need to M corrected gardleee of IM blwmatlon on aDPr pp DIa p1b., Wk9 any w repmd, are required b M on the conetmctlon at Ne gme of inaxctlona. Permit Number: m Custom Soil Resource Report scientists classified and named the soils in the survey area, they compared the individual soils with similar soils in the same taxonomic class in other areas so that they could confirm data and assemble additional data based on experience and research. The objective of soil mapping is not to delineate pure map unit components; the objective is to separate the landscape into landforms or landform segments that have similar use and management requirements. Each map unit is defined by a unique combination of soil components and/or miscellaneous areas in predictable proportions. Some components may be highly contrasting to the other components of the map unit. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The delineation of such landforms and landform segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, onsite investigation is needed to define and locate the soils and miscellaneous areas. Soil scientists make many field observations in the process of producing a soil map. The frequency of observation is dependent upon several factors, including scale of mapping, intensity of mapping, design of map units, complexity of the landscape, and experience of the soil scientist. Observations are made to test and refine the soil -landscape model and predictions and to verify the classification of the soils at specific locations. Once the soil -landscape model is refined, a significantly smaller number of measurements of individual soil properties are made and recorded. These measurements may include field measurements, such as those for color, depth to bedrock, and texture, and laboratory measurements, such as those for content of sand, silt, clay, salt, and other components. Properties of each soil typically vary from one point to another across the landscape. Observations for map unit components are aggregated to develop ranges of characteristics for the components. The aggregated values are presented. Direct measurements do not exist for every property presented for every map unit component. Values for some properties are estimated from combinations of other properties. While a soil survey is in progress, samples of some of the soils in the area generally are collected for laboratory analyses and for engineering tests. Soil scientists interpret the data from these analyses and tests as well as the field -observed characteristics and the soil properties to determine the expected behavior of the soils under different uses. Interpretations for all of the soils are field tested through observation of the soils in different uses and under different levels of management. Some interpretations are modified to fit local conditions, and some new interpretations are developed to meet local needs. Data are assembled from other sources, such as research information, production records, and field experience of specialists. For example, data on crop yields under defined levels of management are assembled from farm records and from field or plot experiments on the same kinds of soil. Predictions about soil behavior are based not only on soil properties but also on such variables as climate and biological activity. Soil conditions are predictable over long periods of time, but they are not predictable from year to year. For example, soil scientists can predict with a fairly high degree of accuracy that a given soil will have a high water table within certain depths in most years, but they cannot predict that a high water table will always be at a specific level in the soil on a specific date. After soil scientists located and identified the significant natural bodies of soil in the survey area, they drew the boundaries of these bodies on aerial photographs and Con �fE IDEZ IAN— APPROVED e<Pi,�e n,.<em..e ro m�e ooPa=:. coa � e;a',o;<a ft rePon Date: n� of oeooa�o<e. Permit Number. m Custom Soil Resource Report identified each as a specific map unit. Aerial photographs show trees, buildings, fields, roads, and rivers, all of which help in locating boundaries accurately. 7 �fE IDEZ IAN— APPROVED e<Pi,�e n,.<em..e ro m�e ooPa=:. coa � >on�io eo<o r,na Poa�o�< ft rePon Date: n� of oeooa�o<e. Permit Number. m Soil Map The soil map section includes the soil map for the defined area of interest, a list of soil map units on the map and extent of each map unit, and cartographic symbols displayed on the map. Also presented are various metadata about data used to produce the map, and a description of each soil map unit. N. E IDR IAN;I- APPROVED T pn1. .eMuP�ee9^ Men roundro Mna.I =emP.nwwitn Custom Soil Resource Report P M.a. emiain„=M... code 3 a.Mi.n=i.. towa n m,w.aw. .nnw.aroMwrr.rna Soil Map rapaNleee oriM lniwmaaon on IN epproraa pone. Tlie N apPrevea p4na, IncIW In9 any requlrMro Mon ^e�co_ n at ft ame of iwwcaona. Date: wad Permit N"mn,r: m.m:,wm 551240 551260 551280 551300 551320 551340 Pr it t x i � Y oil a e lid at his 430 3712" N I 551240 551260 551280 551300 551320 3 In Map Scale: 1:846 if printed on A landscape (11" x 8.5") sheet Meters nN 0 10 20 40 60 N r,3et 0 40 80 160 240 Map projection: Web Mercator Comer coordinates: WGS84 Edge tics: UTM Zone 11N WGS84 C 551360 Y�rt>iW 551340 551360 N b 551380 551400 551420 43o 3716' N I I ' �+�}. 43' 37 12" N 551380 551400 551420 e C:,-yIE IDIAN— APPROVED ze plena hive Men bond b wm wlb . e�nm�p e... cone aoo�.naioond mbaw.uon. Il t. need loMwnacletl gardl.a ndn aDProved pi.- any w epom,are requlrM b M on be conatructlon o,at be dme of inapactlona. te: MAP LEGEND Area of Interest (AOI) Area of Interest (AOI) Soils 0 Soil Map Unit Polygons im 0 Soil Map Unit Lines 0 Soil Map Unit Points Special Point Features of Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit ii Gravelly Spot 0 Landfill Lava Flow Marsh or swamp Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop J Saline Spot d Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip 0o Sodic Spot Custom Soil Resource Report Spoil Area Stony Spot Very Stony Spot ¢ Wet Spot Other •= Special Line Features Water Features Streams and Canals Transportation i Ft Rails r•,,r Interstate Highways US Routes Major Roads Local Roads Background IQ Aerial Photography MAP INFORMATION The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Ada County, Idaho Survey Area Data: Version 9, Sep 9, 2021 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Jun 19, 2020—Jun 27, 2020 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shiftinq of map unit boundaries may be evident. 10 CAE miAx— APPROVED x Dlana Mx Men bond b nMl complknce wIth appIi IMIng C. Code d0tiI. bond at InexNane Il need to M corrected gardleee of IM blwmatlon on aDPr pp Dlapll�bclWb9 any w repmd, are required b M on the conetmctlon at Ne gme of inaxctlona. Permit Number: m Custom Soil Resource Report Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 141 Purdam silt loam, 0 to 2 percent slopes 1.9 100.0% Totals for Area of Interest 1.9 100.0% Map Unit Descriptions The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils. Within a taxonomic class there are precisely defined limits for the properties of the soils. On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic class rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called noncontrasting, or similar, components. They may or may not be mentioned in a particular map unit description. Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management. These are called contrasting, or dissimilar, components. They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps. If included in the database for a given area, the contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been observed, and consequently they are not mentioned in the descriptions, especially where the pattern was so complex that it was impractical to make enough observations to identify all the soils and miscellaneous areas on the landscape. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The objective of mapping is not to delineate pure taxonomic classes but rather to separate the landscape into landforms or landform segments that have similar use and management requirements. The delineation of such segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, however, onsite investigation is needed to define and locate the soils and miscellaneous areas. 11 CAE miAN— APPROVED x Dlana Mx Men bond b nMl complknce wIth appIi Hiking C. Code d0tiI. bond at InexNane Il need to M corrected gardleee of IM blwmatlon on aDPr pp DIa p1b., Wk9 any w repmd, are required b M on the conetmctlon at Ne gme of inaxctlona. Permit Number: m Custom Soil Resource Report An identifying symbol precedes the map unit name in the map unit descriptions. Each description includes general facts about the unit and gives important soil properties and qualities. Soils that have profiles that are almost alike make up a soil series. Except for differences in texture of the surface layer, all the soils of a series have major horizons that are similar in composition, thickness, and arrangement. Soils of one series can differ in texture of the surface layer, slope, stoniness, salinity, degree of erosion, and other characteristics that affect their use. On the basis of such differences, a soil series is divided into soil phases. Most of the areas shown on the detailed soil maps are phases of soil series. The name of a soil phase commonly indicates a feature that affects use or management. For example, Alpha silt loam, 0 to 2 percent slopes, is a phase of the Alpha series. Some map units are made up of two or more major soils or miscellaneous areas. These map units are complexes, associations, or undifferentiated groups. A complex consists of two or more soils or miscellaneous areas in such an intricate pattern or in such small areas that they cannot be shown separately on the maps. The pattern and proportion of the soils or miscellaneous areas are somewhat similar in all areas. Alpha -Beta complex, 0 to 6 percent slopes, is an example. An association is made up of two or more geographically associated soils or miscellaneous areas that are shown as one unit on the maps. Because of present or anticipated uses of the map units in the survey area, it was not considered practical or necessary to map the soils or miscellaneous areas separately. The pattern and relative proportion of the soils or miscellaneous areas are somewhat similar. Alpha -Beta association, 0 to 2 percent slopes, is an example. An undifferentiated group is made up of two or more soils or miscellaneous areas that could be mapped individually but are mapped as one unit because similar interpretations can be made for use and management. The pattern and proportion of the soils or miscellaneous areas in a mapped area are not uniform. An area can be made up of only one of the major soils or miscellaneous areas, or it can be made up of all of them. Alpha and Beta soils, 0 to 2 percent slopes, is an example. Some surveys include miscellaneous areas. Such areas have little or no soil material and support little or no vegetation. Rock outcrop is an example. 12 CAE roiAx- APPROVED x Dlaea tlave Men bond b ntlal complknu wlttl appllude IMldg C. Code degcII nbeedd1rdatNrractatl excMd. Custom Soil Resource Report _u garppp- of IM Nlwmatlon on aDProvetl pi.., b9 any w repmd, are requlredro Mon the toner n at Ne gme of o,inaxcM e. te: Permit Number maxac°m a County, Idaho 141—Purdam silt loam, 0 to 2 percent slopes Map Unit Setting National map unit symbol: 2g70 Elevation: 2,000 to 5,000 feet Mean annual precipitation: 8 to 12 inches Mean annual air temperature: 45 to 52 degrees F Frost -free period: 110 to 160 days Farmland classification: Prime farmland if irrigated Map Unit Composition Purdam, plowed, and similar soils: 90 percent Minor components: 10 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Purdam, Plowed Setting Landform: Stream terraces Down -slope shape: Linear Across -slope shape: Linear Parent material: Mixed alluvium and/or lacustrine deposits and/or loess Typical profile Apt - 0 to 4 inches: silt loam Ap2 - 4 to 10 inches: silt loam Bt1 - 10 to 13 inches: silty clay loam Bt2 - 13 to 19 inches: silt loam Bkq - 19 to 24 inches: silt loam Bkqm - 24 to 38 inches: cemented material 2C - 38 to 60 inches: stratified sand to loam Properties and qualities Slope: 0 to 2 percent Depth to restrictive feature: 20 to 40 inches to duripan Drainage class: Well drained Capacity of the most limiting layer to transmit water (Ksat): Very low to moderately low (0.00 to 0.06 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Calcium carbonate, maximum content: 25 percent Maximum salinity: Nonsaline to slightly saline (0.0 to 4.0 mmhos/cm) Sodium adsorption ratio, maximum: 10.0 Available water supply, 0 to 60 inches: Low (about 4.7 inches) Interpretive groups Land capability classification (irrigated): 3s Land capability classification (nonirrigated): 6c Hydrologic Soil Group: C Ecological site: R011XY0011D -LOAMY 8-12 -Provisional Hydric soil rating: No 13 �fE IDEZ IAN— APPROVED e<Pi,�e n,.<em..e ro m�e ooPa=:. coa � e;a',o;<a rePon Date: n� of oeooa�o<e. Permit Number. m Custom Soil Resource Report Minor Components Elijah Percent of map unit: 3 percent Hydric soil rating: No Abo Percent of map unit: 3 percent Hydric soil rating: No Sebree Percent of map unit: 2 percent Hydric soil rating: No Power Percent of map unit: 2 percent Hydric soil rating: No 14 CAE roiAN— APPROVED x Dlana Mx Men bond b nMl complknce wIth appIi Hiking.dae. Code daflciancI. bond at InexN.e Il need to M.-d gardlaee I. blwmatlon on aDPr pp DIa p1b., Wk9 any w repmd, are requlrM b M on the conetmctlon at Ne gme of inaxctlona. Permit Number: m References American Association of State Highway and Transportation Officials (AASHTO). 2004. Standard specifications for transportation materials and methods of sampling and testing. 24th edition. American Society for Testing and Materials (ASTM). 2005. Standard classification of soils for engineering purposes. ASTM Standard D2487-00. Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of wetlands and deep -water habitats of the United States. U.S. Fish and Wildlife Service FWS/OBS-79/31. Federal Register. July 13, 1994. Changes in hydric soils of the United States. Federal Register. September 18, 2002. Hydric soils of the United States. Hurt, G.W., and L.M. Vasilas, editors. Version 6.0, 2006. Field indicators of hydric soils in the United States. National Research Council. 1995. Wetlands: Characteristics and boundaries. Soil Survey Division Staff. 1993. Soil survey manual. Soil Conservation Service. U.S. Department of Agriculture Handbook 18. http://www.nres.usda.gov/wps/portal/ nres/detail/national/soils/?cid=nres142p2_054262 Soil Survey Staff. 1999. Soil taxonomy: A basic system of soil classification for making and interpreting soil surveys. 2nd edition. Natural Resources Conservation Service, U.S. Department of Agriculture Handbook 436. http:// www. nres. usda.gov/wps/portal/nres/detail/national/soils/?cid=nres l42p2_053577 Soil Survey Staff. 2010. Keys to soil taxonomy. 11th edition. U.S. Department of Agriculture, Natural Resources Conservation Service. http:// www. nres. usda.gov/wps/portal/nres/detail/national/soils/?cid=nres l 42p2_053580 Tiner, R.W., Jr. 1985. Wetlands of Delaware. U.S. Fish and Wildlife Service and Delaware Department of Natural Resources and Environmental Control, Wetlands Section. United States Army Corps of Engineers, Environmental Laboratory. 1987. Corps of Engineers wetlands delineation manual. Waterways Experiment Station Technical Report Y-87-1. United States Department of Agriculture, Natural Resources Conservation Service. National forestry manual. http://www.nres.usda.gov/wps/portal/nres/detail/soils/ hom e/?cid=nres 142 p2_053374 United States Department of Agriculture, Natural Resources Conservation Service. National range and pasture handbook. http://www.nres.usda.gov/wps/portal/nres/ detail/national/landuse/rangepasture/?cid=stelprdb1043084 15 �fE IDEZ IAN— APPROVED Permit Numb<r. ry Custom Soil Resource Report United States Department of Agriculture, Natural Resources Conservation Service. National soil survey handbook, title 43041. http://www.nres.usda.gov/wps/portal/ nres/detail/soils/scientists/?cid=nres 142p2_054242 United States Department of Agriculture, Natural Resources Conservation Service. 2006. Land resource regions and major land resource areas of the United States, the Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook 296. http://www.nres.usda.gov/wps/portal/nres/detail/national/soils/? cid =nres 142 p 2_0 53624 United States Department of Agriculture, Soil Conservation Service. 1961. Land capability classification. U.S. Department of Agriculture Handbook 210. http:// www.nrcs.usda.gov/lnternet/FSE—DOCUMENTS/nrcsl42p2_052290.pdf 16