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NE 114, SW 1 ., R.5E,
<br />CITY OF EVERETT, WASHINGTON
<br />SOIL RETENTION.,
<br />THE DUFF LAYER AND NATIVE TOPSOIL SHOULD BE RETAINED IN AN UNDISTURBED STATE
<br />TO THE MAXIMUM EXTENT PRACTICABLE. IN ANY AREAS REQUIRING GRADING REMOVE AND
<br />STOCKPILE THE DUFF LAYER AND TOPSOIL ON SITE IN A DESIGNATED, CONTROLLED AREA,
<br />NOT ADJACENT TO PUBLIC RESOURCES AND CRITICAL AREAS, TO BE REAPPLIED TO OTHER
<br />POR77ONS OF THE SITE WHERE FEASIBLE.
<br />SOIL QUALITY.•
<br />THE RESULTING SOIL SHOULD BE CONDUCIVE TO THE TYPE OF VEGETATION TO BE
<br />ESTABLISHED. ALL AREAS SUBJECT TO CLEARING AND GRADING THAT HAVE NOT BEEN
<br />COVERED BY IMPERVIOUS SURFACE, INCORPORATED INTO A DRAINAGE FACILITY OR
<br />ENGINEERED AS STRUCTURAL FILL OR SLOPE SHALL, AT PROJECT COMPLETION,
<br />DEMONSTRATE THE FOLLOWING:
<br />1. A TOPSOIL LAYER WITH A MINIMUM ORGANIC MATTER CONTENT OF TEN PERCENT
<br />DRY WEIGHT IN PLANTING BEDS, AND 51-� ORGANIC MATTER CONTENT (BASED ON A
<br />LOSS -ON -IGNITION TEST) IN TURF AREAS, AND A PH FROM 6.0 TO 8.0 OR
<br />MATCHING THE PH OF THE ORIGINAL UNDISTURBED SOIL, THE TOPSOIL LAYER SHALL
<br />HAVE A MINIMUM DEPTH OF EIGHT INCHES EXCEPT WHERE TREE ROOTS LIMIT THE
<br />DEPTH OF INCORPORATION OF AMENDMENTS NEEDED TO MEET THE CRITERIA.
<br />SUBSOILS BELOW THE TOPSOIL LAYER SHOULD BE SCARIFIED AT LEAST 4 INCHES
<br />WITH SOME INCORPORATION OF THE UPPER MATERIAL TO AVOID STRATIFIED LAYERS,
<br />WHERE FEASIBLE.
<br />2. PLANTING BEDS MUST BE MULCHED WITH 2 INCHES OF ORGANIC MATERIAL.
<br />3. QUALITY OF COMPOST AND OTHER MATERIALS USED TO MEET THE ORGANIC CONTENT
<br />REQUIREMENTS.
<br />A. THE ORGANIC CONTENT FOR PRE-APPROVED°.AMENDMENT RATES CAN BE MET
<br />ONLY USING COMPOST MEETING THE COMPOST SPECIFICATION FOR
<br />BIORETENTION (BMP T7.30), WITH THE EXCEPTION THAT THE COMPOST MAY
<br />HAVE UP TO 357. BIOSOLIDS OR MANURE
<br />B. COMPOST USED IN BIORETENTION AREAS SHOULD BE STABLE, MATURE AND
<br />DERIVED FROM YARD DEBRIS, WOOD WASTE, OR OTHER ORGANIC MATERIALS
<br />THAT MEET THE INTENT OF THE ORGANIC SOIL AMENDMENT SPECIFICATION.
<br />BIOSOLIDS AND MANURE COMPOSTS CAN BE HIGHER IN BIOAVAILABLE
<br />PHOSPHORUS THAN COMPOST DERIVED FROM YARD OR PLANT WASTE AND
<br />THEREFORE ARE NOT ALLOWED IN BIORETENTION AREAS DUE TO THE
<br />POSSIBILITY OF EXPORTING BIO-AVAILABLE PHOSPHORUS IN EFFLUENT.
<br />C. THE COMPOST MUST ALSO HAVE AN ORGANIC MATTER CONTENT OF 357. TO
<br />65%, AND A CARBON TO NITROGEN RATIO BELOW 25:1.
<br />D. THE CARBON TO NITROGEN RATIO MAY BE AS HIGH AS 35: 1 FOR PLANTINGS
<br />COMPOSED ENTIRELY OF PLANTS NATIVE TO THE PUGET SOUND LOWLANDS
<br />REGION
<br />CALCULATED AMENDMENT RATES MAY BE MET THROUGH USE OF COMPOSTED
<br />MATERIAL MEETING THE REQUIREMENTS ABOVE; OR OTHER ORGANIC MATERIALS
<br />AMENDED TO MEET" THE CARBON TO NITROGEN RATIO REQUIREMENTS, AND NOT
<br />EXCEEDING THE CONTAMINANT LIMITS IDENTIFIED IN TABLE 220-B, TESTING
<br />PARAMETERS, IN WAC 173-350-220.
<br />IMPLEMENTATION OPTIONS:
<br />THE SOIL QUALITY DESIGN GUIDELINES LISTED ABOVE CAN BE MET BY USING ONE OF THE
<br />METHODS LISTED BELOW.
<br />1. LEAVE UNDISTURBED NATIVE VEGETATION AND SOIL, AND PROTECT FROM COMPACTION
<br />DURING CONSTRUCTION.
<br />2. AMEND DISTURBED SOIL ACCORDING TO THE FOLLOWING PROCEDURES:
<br />A. SCARIFY SUBSOIL TO A DEPTH OF ONE FOOT.
<br />B. IN PLANTING BEDS, PLACE THREE INCHES OF COMPOST AND TILL IN TO AN
<br />EIGHT -INCH DEPTH.
<br />C. IN TURF AREAS, PLACE TWO INCHES OF COMPOST AND TILL IN TO AN
<br />EIGHT -INCH DEPTH.
<br />D. APPLY TWO TO FOUR INCHES OF ARBORIST WOOD CHIP, COARSE BARK MULCH,
<br />OR COMPOST MULCH TO PLANTING BEDS AFTER FINAL PLANTING.
<br />3. AMEND ON A SITE -CUSTOMIZED MANNER SO THAT IT MEETS THE SOIL QUALITY
<br />CRITERIA SET FORTH ABOVE, AS DETERMINED BY A LICENSED ENGINEER, GEOLOGIST,
<br />LANDSCAPE ARCHITECT, OR OTHER PERSON AS APPROVED BY SNOHOMISH COUNTY.
<br />4. STOCKPILE EXISTING TOPSOIL DURING GRADING, AND REPLACE IT PRIOR TO PLANTING.
<br />STOCKPILED TOPSOIL MUST BE AMENDED IF NEEDED TO MEET THE ORGANIC MATTER
<br />AND DEPTH REQUIREMENTS BY FOLLOWING THE PROCEDURES IN THE PREVIOUS
<br />BULLET
<br />5. IMPORT TOPSOIL MIX OF SUFFICIENT ORGANIC CONTENT AND DEPTH TO MEET THE
<br />ORGANIC MATTER AND DEPTH REQUIREMENTS.
<br />MORE THAN ONE METHOD MAY BE USED ON DIFFERENT PORTIONS OF THE SAME SITE.
<br />SOIL THAT ALREADY MEETS THE DEPTH AND ORGANIC MATTER QUALITY STANDARDS, AND
<br />IS NOT COMPACTED, DOES NOT NEED TO BE AMENDED.
<br />MAINTENANCE
<br />1, SOIL QUALITY AND DEPTH SHOULD BE ESTABLISHED TOWARD THE END OF
<br />CONSTRUCTION AND, ONCE ESTABLISHED, SHOULD BE PROTECTED FROM COMPACTION,
<br />SUCH AS FROM LARGE MACHINERY USE, AND FROM EROSION.
<br />2. SOIL SHOULD BE PLANTED AND MULCHED AFTER INSTALLATION.
<br />3. PLANT DEBRIS OR ITS EQUIVALENT SHOULD BE LEFT ON THE SOIL SURFACE TO
<br />REPLENISH ORGANIC MATTER.
<br />SOIL "ENDMElff LEGEND
<br />UNDISTURBED SOIL
<br />AMENDED SOILS
<br />OIL TEST PIT L0GS-
<br />TEST PIT 1 (TP-1)
<br />0"-12": TOP SOIL
<br />12"-48": LIGHT BROWN LOOSE TO MEDIUM -DENSE SLIGHTLY SILTY FINE SAND
<br />48'-108°: LIGHT GRAY MEDIUM -DENSE SLIGHTLY SILTY FINE SAND (ADVANCE OUTWASH)
<br />> 1051. TEST PIT TEMINIATED AT 9.0 FEET
<br />TEST PIT 2 (T P-2)
<br />0"-12": TOP SOIL
<br />12"-36": LIGHT BROWN LOOSE TO MEDIUM -DENSE SLIGHTLY SILTY FINE SAND
<br />36"-96": LIGHT GRAY DENSE FINE SAND. (ADVANCE OUTWASH)
<br />>96": TEST PIT TEMINIATED AT 8.0 FEET
<br />TEST PIT 3 aE-3)
<br />0"-12": TOP SOIL
<br />12"-66": LIGHT BROWN LOOSE TO MEDIUM -DENSE SILTY FINE SAND
<br />66"-120": LIGHT GRAY DENSE SLIGHTLY SILTY FINE SAND (ADVANCE OUTWASH)
<br />> 12D': TEST PIT TEIROItN'9ATED AT 10.0 FEET
<br />TEST PIT 4�(TP-4)
<br />0'-12 TOP SOIL
<br />12"-36": BROPYN LOOSE TO MEDIUM -DENSE SILTY FINE SAND
<br />36"-96 LIGHT BROWN DENSE SLIGHTLY SILTY FINE SAND (ADVANCE OUTWASH)
<br />>96": TEST PIT TEMINIATED AT 8.0 FEET
<br />TEST PIT 5`TP-5,�
<br />0"-12": TOP SOIL
<br />12"- : LIGHT BROWN LOOSE TO MEDIUM -DENSE SILTY FINE SAND
<br />48"-102'. LIGHT GRAY DENSE SLIGHTLY FINE TO MEDIUM SAND (ADVANCE OUTWASH)
<br />> 102": TEST PIT TEMINIATED AT 8.5 FEET
<br />7EST P T TP6)
<br />0"-8": TOP SOIL
<br />8"-421: BROWN TO LIGHT BROWN LOOSE TO MEDIUM -DENSE SLIGHTLY SILTY FINE SAND
<br />42"-96": LIGHT GRAY DENSE FINE TO MEDIUM SAND (ADVANCE OUTWASH)
<br />>96": TEST PIT TEMIN14TED AT 8.0 FEET
<br />SURFACE AREA DETERMINED
<br />AT TOP OF WEIR 4' MIN.
<br />1' MIN. OVERFLOW
<br />1' MIN.
<br />I' MIN.
<br />ry.
<br />y 3.5'-5'
<br />T1-5�MIN.
<br />FLAT BOTTOM
<br />314"-1.5"
<br />WASHED GRAVEL
<br />RIPRAP
<br />2"
<br />TO 4" ROCK
<br />GEOTEA71LE
<br />TYPICAL CROSS SECTION
<br />DISCHARGE TO STABILIZED
<br />CONVEYANCE, OUTLET OR
<br />SMIMNiT TW,MOE
<br />LEVEL SPREADER
<br />NEW DETENTION PIPE SYSTEM MAY BE
<br />USED AS A TEMPORARY SEDIMENT TANK,
<br />- 6'. MIN,
<br />-�
<br />UPON CITY APPROVAL, DURING
<br />CONSTRUCTION PROVIDED SYSTEM DOES rr-rr=rr-�
<br />NOT OUTLET INTO NEW SEWER SYSTEM I I=III=III=
<br />III
<br />I' MIN. DEPTH OVERFLOW SPILLWAY
<br />AND DETENTION SYSTEM IS FLUSHED AND.
<br />-I 11=
<br />11=
<br />IF
<br />CLEANED PRIOR TO USE.
<br />I I
<br />�)
<br />I
<br />NATIVE SOIL OR
<br />I
<br />v;.:•.'"a.,...°,
<br />! MIN. 1 ' DEPTH
<br />- '.. ` :::'.:'':", -:.•.:�....,;.. ::
<br />COMPACTED BACKFILL
<br />-I (-�''.. •: I-
<br />,I_III-:: '::` : ~`: ::'' -
<br />2" TO 4" ROCK
<br />MIN. I' DEPTH
<br />GEOTEXTILE
<br />a" TO 1.5"
<br />TRAP OUTLET
<br />WASHED GRAVEL
<br />7'E' O S D.M -TRAP DETAIL
<br />PER DOE BMP C240
<br />SEDIMENTTW CAL C.
<br />2-YEAR PEAK RUNOFF RATE = 0.122 CFS.
<br />FS (FACTOR OF SAFETY) = 2
<br />Vs (SETTLING VELOCITY) = 0.00096 FT/SEC.
<br />SURFACE AREA REQUIRED = 254 SF
<br />DESIGNED SURFACE AREA = 484 SF.
<br />SPILLWAY = 262.0
<br />TOP = 261.0
<br />TOE = 257.5
<br />EX. SSCO
<br />EX. CB
<br />INLET RIM 258.30
<br />9
<br />EX. SDMH
<br />RIM 258 03
<br />IE 8" N 253.1
<br />EX. CB I
<br />INSTALL CATCH BASIN
<br />SEDIMENT INSERTS
<br />260 - - -
<br />CAL.0
<br />26
<br />-- ` - - 2 4
<br />TEMPORARY
<br />SEDIMENT TRAP
<br />- TP 5
<br />PER DOE BMP
<br />- 7 26 -
<br />- - C240
<br />S,01 7 O.TE °
<br />_
<br />NEW DETENTION PIPE SYSTEM MAY BE
<br />26
<br />USED AS A TEMPORARY SEDIMENT TANK,
<br />UPON CITY APPROVAL, DURING
<br />CONSTRUCTION PROVIDED SYSTEM DOES
<br />270
<br />_
<br />NOT OUTLET INTO NEW SEWER SYSTEM
<br />i \ o
<br />AND DETENTION SYSTEM IS FLUSHED AND
<br />LOT 2 '
<br />_ \ o
<br />CLEANED PRIOR TO USE.
<br />4 72
<br />n
<br />O
<br />27
<br />Q ` o
<br />N
<br />D_
<br />o
<br />Ld
<br />_ _ _ 276
<br />278
<br />o•
<br />�14 FENCE
<br />282
<br />- -
<br />f I
<br />254
<br />286 - 1 4 HOUSE
<br />JSE #812 1
<br />_ \\
<br />S 87'3557"
<br />16, 00'
<br />00472900000401
<br />0
<br />LEGEND
<br />i
<br />RIGHT-OF-WAY CENTER LINE
<br />PROPERTY LINE
<br />- -�-
<br />RIGHT OF WAY
<br />- -
<br />EXISTING LOT LINES
<br />❑HP -
<br />EXISTING POWER (AERIAL)
<br />-SS Cam-
<br />EXISTING SANITARY SEWER
<br />Z S D
<br />EXISTING STORM DRAIN
<br />- - -- -
<br />EXIS77NG CONTOURS
<br />/7777,
<br />EX. EDGE OF PAVEMENT
<br />L1
<br />EXISTING CATCH BASIN (CB)
<br />©
<br />EXISTING STORM MANHOLE (SDMH)
<br />0
<br />EXISTING SEWER MANHOLE (SSMH)
<br />tit
<br />EX. FIRE HYDRANT
<br />FE
<br />EX. WATER METER
<br />-C�-
<br />EX. POWER POLE
<br />E----
<br />EX. UTILITY POLE ANCHOR
<br />EXISTING CONCRETE
<br />EXISTING ADJACENT BUILDING
<br />' PPLEGEN
<br />XXX
<br />PROPOSED CONTOUR LINE
<br />CLEARING LIMITS PER DOE BMP C 103
<br />MULCH &IOR STRAW MATTING
<br />PER DOE BMP C121
<br />PRESERVE NATIVE VEGETATION
<br />PER DOE BMP C101
<br />SF
<br />SILT FENCE PER COE STD DWG #214
<br />-
<br />TEMPORARY CONSTRUCTION ENTRANCE
<br />PER COE STD DWG J201
<br />ZIT
<br />INTERCEPTOR TRENCH WITH DIKES
<br />co
<br />>
<br />PER DOE BMP C200
<br />ss#19® 01
<br />REVIEWED FOR PERMIT
<br />
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