HomeMy WebLinkAboutR-417746BIORETENTION SOIL MEDIA STANDARD
SPECIFICATIONS
11-C.1 COMPOST
Compost products shall be the result of the biological degradation and moroonnation ofunixntanhnakd
biological organic materials under condolled conditions designed to promote aerobic decomposition.
Compost shall be stable with regard to oxygen consumption, carbon dioxide generation, and sad
germination and seedling vigor. Compost shall be manure with regard to its suitability for use in
etormwener facilities and BMPs, post-Ponsmichon soil am.ndmen4 genes landscaping, m an erosion
control ENT as defined below.
Compost shall be tested at aminim=in accordance with the U.S. Composting Council'Testing Methods
for the Examwation of Compost and Composing" (T'MECC), as established in &a Composting Council's
"Sea] of Testing Assurance" (STA) program. Most Washington compost facilities now use these tests. All
tests most be done on compost screened in specification for its Intended use.
11-C.LA SPECIFICATION 1 COMPOST
1. Compost most be produced a afacility thin is permitted by the jurisdictional health authority.
Permitted comport facilities In Washington are included on a list available at
mtte'/tv myweeeov/ommams/swfa/o esrail.html>.
2. Compost moat road the definition of "composted material"In WAG 173-350-100, and main comply
with testing pmmcetere and other standards including not exceeding wnwainant limits identified in
Table 220-B. Testing Parameters, In WAG 173-350-220; and "Physical conta dmads" (as defined In
WAG 173-350-100) general less than 1%by weight (TMECC 03.08-A) tend, not an exceed
025 percent film plastic by dry weight.
3. The compost product must originate a minimum of 65 percent by volume from recycled plant waste
composed of -yard debris," "crop residues," and %uffd%agents" as thine terms; are defined in
WAC 173-350-IOD. A maximum of 35 percent by volume of "postconsmner food waste' as defined
In WAC 173-350-100 maybe substituted for recycled plant waste. Monoliths, manure, and/or bedding
straw orwood chips or shavings containing animal exereBi are net allowed.
4. Wood wines from chemically treated lumber and manufactured wood products containing adhesives
or any other chemical is not allowed; painted and stained wood are not allowed; and only sawdust
Down virgin lumber allowed. No other toxic or otherwise handful rnat is are allowed.
5. For high -density residential subdivision development, mulfi famity, commercial, and industrial
projects, and roadprojects considered high ADTpribuds,t the Manufacturer re- Vmdo shall Provide
To the end buyer a list of feeddr ck bourns by percentage by volume In the two compost protlud.
6. Compost shag have a moisture content that has no visible five water or dust produced when handling
the material.
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2017 City ofRemen Surface Water Deem Mosul IMM16
11C-1
REFERENCE II: MAcHiRALS
7. Compost shall have an organic matter content of40 percent to 65 percent by dry weight as ddermived
by loss of ignition test method ASTM D 2974, or by U.S. Composting Council TMECDC 05.07A
-Lows-On-Ignition Organic Matter Method NJOH."
8. Compost shell haw a carbon in nitrogen ratio below 25:1, although the carbon in nitrogen ratio may
be as high as 35:1 for plantings composed entirely of plants native in the Pugd Sound Lowlands
region. The carbon to nitrogen TWO shall be calculated on a dry weight basis using TMECC 5.02A
("Carbon to Nitrogen Ratio'), which uses TMECC 04.01A, "Organic Cabon" divided by the dry
weight of Total N" (TMECC 04.02D).
9. Compost pH shall be between 6.0 and 8.5 when hated In accordance with U.S. Composting Council
TMECC 04.11-A, "1:5 Slurry pH."
10. Soluble silt content shell be lees than 4.0dS/m(mmhoa/can) when boded in woordence with
U.S. Composting Council TMECC 04.10 "Electrical Conductivity, 1:5 Slurry Method, Mass Basis"
11. Compost maturity indicators from a member bioassay (TMECC 05.05-A "Germination Seedling
Emergence and Relative Growth) mod be greeter Nan 805s for both emergence and vigor").
12. Stability shell be 7-mg CO2-C/gOM/day m below in as determined by U.S. Comprising Council
TMECC 05.08-B 'Cuban Dioxide Evolution Rate," in establish low oxygen use and low CO2
generation Wow.
Compost shell be seemed in the Five Compost size gradation specification in Section I -C. IC of this
Reference.
11-C.1.11 SPECIFICATION 2 COMPOST
1. Specification 2 Compost manufexuring, feedstocks, and testing are all identical to Specification I
Compost except thin:
a) Amaximom of 35 percent by volume ofbiosolids or manors may be substimed for recycled plant
wade.
b) Compost may before" comae gradation depending on use and need TO meet other screened
material quality criteria
of Carbon to Nitrogen ratio may be up to 40:I for gearae compost in be used a a surface mulch host
to a soil mix).
11-C.LC COMPOST SCREENING SIZE GRADATIONS
Where compost gradation is specified, it mod meet the following size gradations when ststed in
accordance with the U.S. Composing Council "Ted Methods for the Examination of Compost and
Composting" (TMECC) Test Method 02.02-B.
Fine Compost shall meet the following gradation by dry weight:
Minimum percent pawing 2"sieve 1000/o
Minimum percent passing)" sieve 99a/o
Minimum percent passing 5/8"sieve 90%
Minimum pement passing 1/4"sieve 75%
Coors Compost shell meet the following gradation by dry weight
Minimum Percent passing 3" sieve
100•h
Minimum Percent passing I" sieve
90%
Minimum Percent passing 3/4" sieve
70%
Minimum Percent passing 1/4"since
4094
1VIM16
2017 Cary oHwwbe Surfiu Water Design Maul
11C-2
11-C.LD COMPOST ACCEPTANCE REQUIREMENTS
The Contractor shall submit the following information in the King County Department of Permitting and
Envimamental Review (DRIER) Engineer for approval:
1. If the manufacturer is nor exempt under Table 220-A,'Terms and Conditions for Solid Wasm Permit
Exempfions," a copy of the Solid Waste Handling Pemdt issued to the compost manufacturer by the
Jurisdictional Health Department in accordance with WAG 173-350 (Minimum Functional Standards
for Solid Waste Handling) or for biowlids compos s a copy of the Coverage Under the General Permit
for Biosofids Management issued to the mamrfactuar by the Department of Ecology in accordance
with WAG 173-308 (Biowlids Management).
2. The Applicant shall provide written verification and lab analyses that the maedal complies with the
processes, testing, and standards specified in WAG 173-350 and these Specifications. An independent
Sea] of Testing Assumnee (STA) Program certified labmdmy2 or a laboratory accredited by WA
Emlogy3 for the specified methods shall perfomr the analyses. Lab analysis "I be for the compost
delivered on site for project use.
3. A copy of the STA laboratory's Sml of Testing Assurance STA certification as issued by the
U.S. Composting Council, or a copy of the EcologyHoertified labomtery's accreditation for the
specified methods.
11-C.2 BIORETENTION SOIL MIX SPECIFICATIONS
Follow the specification below for the approved defuela bioseteedon soil mix. Alterations in this
specification require an approved adjustment.
11-C.2.A DEFAULT BIORETENTION SOIL MIX
Businessmen Sod Mix (BSM) shall be a well -blended homogeneous mixture ofI iordention Mineral
Aggregate and I imekntiw Compost measured on a volume basis composed of.
• 35 W 40percent byvohaw Specification 1 Compost per Section H-C.LA above and
Section I IC.2.11 below.
• 60 to 65 percent bywhrme Biordmtion Mineral Aggregate per Section 11C.2.0 below.
Projects which prefer to create a custom Biormention Soil Mix rawer than using the default requirement
above must demonstrate compliance with criteria Be described In Ecology's Stor immear Management
Manual for Western Washington (2014) Volume V- RunmF Transient BMPs, except that my moo
stringent compost criteria required by this Reference I IC are applicable.
11-C.2.B BIORETENTION COMPOST
Bio dantion Compost shall be Specification 1, Fine Compost per Sections; I IC.IA and I ICAG of this
Reference. Fine Specification 1 Compost shall be used for Biordenfion Soil Mix and for any compost used
W normal bioretentlora cell soil.
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2017 City ofReaton Surface Water Daipy Manual 1XV1016
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11-C.2.0
11-C<3
Aggregate Gradation
SOIL MIX AGGREGATE
The following Bible Provides a gradation guideline for the aggregate component of Biorekntion Soil Mix
specification In weaken Washington. This sued gradation is often supplied in a well -graded utility in
screened With compost, this blend provides enough fines for adequate water retention, hydraulic
conductivitywithin recommended range (ace below), pollutant removal capability, and plant growth
characteristics for meeting design guidelines and objectives.
TABLE lIC.2.A BIORETENTION SOD. MIX
MINERAL AGGREGATE GRADATION
81eve S
Percent Passing
M.
100
#4
95-100
#to
75--90
#40
25
#100
4-10
#200
2<
Whom existing aids meet the above aggregate gradation, those soils may be amended rather flow
importing mineral aggregate.
MULCH
Mulch may only be composed of either chipped wood as defined in Section 11C.3A, or compost as
defined In Section I IC.3.B. Mulch may not be made of synthetic materials Including but mot limn edbe
recycled tire material, vmgm rubber mineral, plastics; or preen postaonsumer cardboard.
ilQeww�c�\7151]7��),'[g g 1 III' ull al
Arbmid Wood Chip Mulch shag be coarse ground wood chips (appmximately 1/2" in 6" along the longest
dimeoeion) derived from the mechanical grinding or shredding of the above -ground psonaws of5aea. It
may woman wood, wood fiber, bank branches, and leaves, but may ram contain visible=n bof ad. It
shall be free of weeds and weed seeds including but not limited to plank on the King County Noxious
Weed list available at: < kingcomty vog /weeds>, and shall be free of invasive plant portions capable
ofre-spmab ing, Including but not limited to horsetail, ivy, clematis, knotweed, me. It may not contain
more than 0.5%by dry weight of manufactured inert material (plastic, concrete, ceramics, metal, eteJ.
Arboreal Wood Chip Mulch, when tested, shall meet Die following Imse volume gradation:
TABLE 11-C.3.A ARBORIST WOOD MULCH GRADATION
$is" Size
Percent Passing
l inch
100
r
95-100
1"
R 100
51B
Od0
No.4
0-30
REFERENCB I IC: BIOREIENTION SOd MEDIA STANDARD SI'ECMCAITONS
Prior in delivery, the Applicant shall provide the following:
L The source of the product and species of trees included in it;
2. A move analysis verifying the product meets the above size gradation requirement;
3. ArepreamBi w sample of the product for County approval.
11-C.3.11 COMPOST MULCH SPECIAL REQUIREMENTS
• Compost Mulch fan Biorekntion must mat the Specification 1 compost requimwxms of
Section 11-C.I.A, except that the gredntim must be Come Compost per Section 11C. LC
• Compost Match for other feciliecs and DMPs mud meet tither Specification l or Specification
compost of Section 11-C.LA or 11C.13 respectively, except that the gradation must be Come
Compost per Section 11-C.LC.
2017 City ofRenwn Surface Water Design Maud
lV1f2016
TABLE 611 UNDERDRAIN AGGREGATE
Sim Sirs
Percent Passing
Minch
100 percent
A inch
wtompearcont
U.S. No. 8
20 to 50 percent
U.S. No. 50
3 to 12 percent
U.S. No. 200
0 to 1 Percent
6.8.1.2 INSTALIATION
EBoavatlon
Soil compaction can lead to facility failure; accordingly, minimizing compaction of the base and sidewalls
of the Indexation area is critical. Excavation should never be allowed during wet or saturated conditions
(compaction can reach depths of2.3 fed during we conditions and mitigation is likely net be possible).
Excavation should be performed by machinery operating adjacent to the biordention facility and no heavy
equipment with narrow tracks, narrow tires, or large lugged, high pressure tires should be allowed on the
bottom of the biowwdion facility. If machinery must operate in the biondention cell for excavation, use
light weight, low groundoiontact pressure equipment and rip the base at completion to refracnue soil to a
minimum of 12 inches. Ifmachivery operates in the facility, subgrade infiltration mks must be field Wood
and compared to design now. Failure to mad or exceed the design infiltration rate will require revised
engineering designs to verify achievement of treatment and flow control benefik that were estimated in the
Stormwater Site Plan.
Prior to placement of the biorchantion soil mix, the finished subgrade shall:
• Be scufiedm ammmum depth WIFE inches.
• Have my sediment deposited from constmetim mnoffremoved. To remove all introduced sediment,
subgmde soil should be removed to a depth of 3-6 inches and replaced with bionromen soil min.
• Be inspeotedbythe responsible engineer teverlfyrequired subgrade condition.
Sidewalls of the facility, beneath the surface of the biordention and mix, can be vertical if sod stability is
adequate. Exposed sidewalls of the completed bioreteation area with Incrustation soil mix w place should
be no steeper Nan 3H:IV. The bottom of the facility should be fat.
Soil Placement
Orik soil mixing or placement shall not be performed ifbicrekvtion soil mix or subgrade soil is
s wended. The biorekntion soil mixture should be placed and graded by machinery operating adjacent be
the bioatention facility. If machinery must operate in the bionetention cell for soil placement use light
weight equipment with low groundconBict pressure. If machinery operates in the facility, subgrade
infiltration mks must be field tested and compared to design rates. Failure to used or exceed the design
mfiltivion rate will require revised mgweering designs to verify achievement oftrea[men[ and Now
control benefits that were estimated In the Stermwater Site Plea
The sell mixture shall be placed in horizontal layers not to exceed 12 inches per lift for the entice ass of
the bimmmtion facility.
Compact the bioretention soil mix te a relative compaction of 85 percent of modified maximum dry
density (ASTM D 1557). Compact m can be achieved by boot packing (simply walking over all areas of
each lift), and then apply 0.2 Inches (0.5 cm) of water per 1 Inch (2.5 cm) ofbioretevfim soil mix depth.
Water for addling should be applied by spaying or sprinkling.
Temporary Erosion and Sediment Control (TESC)
Controfiwg erosion and sediment are most difficult during clearing, grading, and crosWct
accordingly, minimizing site disturbance to the grown extend practicable is the most effective sediment
management During comwmmction:
• Biorelention facilities should not be used We sediment control facilities and all drainage should be
directed away from biordmtion facilities after initial rough grading. Flow can be directed away font
the facility with temporary diversion swales or other approved protection. Ifwaoduchon of
construction Banff cannot be avoided We below for guidelines.
• Construction on beretradonfacilities should not begin will all contributing drainage area are
stabilized according to erosion and sediment control BMPs and to the satisfaction of the engineer.
• If the design includes curb and goer, the curb cuts and inlets should be blocked=61 bioretention ail
mix and mulch have been placed and planting completed (when possible), and dispersion pads are In
place.
Every effort during design, mns bon sequencing and covstrvction should be made in prevent sediment
from marring bicretmtiov facilities. However, bimeteution areas are often distribmed throughout the
project area and can Pasant unique challenges during construction.
Erosion and sediment control practices moat be inspected and maintained on a agular basis.
Li;Ig OO
Ifusing the default biordention soil mix, pre -placement laboratory analysis for awarded hydraulic
conductivity of the btorekntiov soil mix is am required. Verification of the mwmd aggregate gradation,
compliance with the compost specifications, and the mix moo must be provided
If wing a custom bidesention soil media, verification of compliance with the minimum design criteria
cited show far such custom muse maybe provided. This will require laboratory stating of the material
Nat will be used in the installation. Testing "I be performed by Seal of Testing Assurance, AASHTO,
ASTM or ad=standards organizffiion accredited laboratory with current and maintained certification.
Samples for testing must be supplied from the bioretention soil mu that will be placed in the bioretension
areas.
If testing infiltration ones is necessary for poetconatm um verification use the Prim Infiltration Test
(PH) method or a double ring infhltromder test (or other smalladde testing allowed by the local
government with jurisdiction). If wing the PIT method, do net exwvete hiordention Wait mu (conduct test
at level of finished bioeleation soil mix elevation), use a maximum of inch pending depth and conduct
test before plains are installed
NOTES:
1. SPECIFICATIONS SHOWN HERE ARE FROM THE CITY OF RENTON AMENDMENTS TO THE KING
COUNTY SURFACE WATER DESIGN MANUAL 2017.
R-41770461
IN COMPLIANCE WITH CITY OF RENTON STANDARDS
"( WSP US4AC pEVELOPMFMEXOIXFEPoXn
1 WI9N Aveme South 1VIM16 2017 Cary ofRdwe Sordid Water Desp Mmnal
CALL 48 HOURS BSawuie aaa 11Ca I V I L P E R M I ichavez 08/25/2021
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SYM RENSION BY APPROVED DATE SYM REVISION BY APPROVED DATE DRAWN DATE SVIETTIE CURREM REVISION SYMBOL rr DATE
ACCEPTABILITY JDM 07 09 21 STORM DETAILS C180949 �R V 07/09/21
ORIG APRON R - CENTRAL C180242 WSP SPT 07/09/21 �¢N ?. T THIS DESIGN AND/OR H K
R�.E w'RG SPECIFICATION IS APPROVED SPT 07/09/21 Sr E_T
BOE/NG® y °=mTI� APRON R - CENTRAL
C501-6K C46
APPROVED BY DEPT. DAIS JDM 07/09/21
CHECKED
APPROVED RENTON SITE JOB NO, C180242 COMP Nu
APPROVED DWG NO,
CIVIL MASTER `, 11 RENTON, WA RTN-YD-0501-6K