Using ASTM C330 Expanded Slate Sand to Meet NC DEQ...
Transcript of Using ASTM C330 Expanded Slate Sand to Meet NC DEQ...
PRESENTER:Debbie Stringer
Stormwater BMP Construction I&M , Horticulturist
Using ASTM C330 Expanded SlateSand to Meet NC DEQ Guidelines for
Bioretention Media
ASTM C330: Structural LWAggregate – Shale, Clay and Slate
North Carolina has meta-argilliteThe slate is formed from volcanic ash which was deposited in a
wet environment and compressed under extreme pressures formillions of years. The slate deposit is located in the foothills east
of Charlotte.
Conveyance toRotary Kilns
Extraction ofRaw Material
Crushing, Grading, Screening,Washing, then to QC Lab
CharacteristicsPorosity 49%
Bulk Density 58lbs/ftᶾ
Relative Density (SG) 1.88
Absorption 11-12%
Compressive Strength 38,000 lbs/ft² (fines)41,000 lbs/ft² (coarse)
CEC Coarse 26 me / 100g
CEC Fines 10-12 me / 100g
Heavy metals < 0.01mg /L
pH 8.5 stable More Angularity& Surface Area
9
Washed medium coarse sand 75-80%blended with
Fines (silt / clay fraction) 12-13%
Organic Matter - pine bark10-20% by volume
(5-10% by compressed weight)(3-6% by combusted dry weight)
ASTM C330 Bioretention Media
HydraulicConductivity
Ksat @ 20° C
cm/sec cm/hr in/min in/hr
With 100%Standard Proctor
Compaction(ASTM D 5084)
0.0006 2.16 0.015 0.9
WithoutCompaction
(ASTM D 2434)0.012 41.4 0.27 16
Compaction byboots, equipment
and weather
C330 Research with SCMs
First IWS in NCNCSU BAE Research 2005
Graham HS, Graham NC
N. Mecklenburg Recycling Center 2009
C33 80% Sand / 15% silt clay / 5% compost C330 80% Sand / 20% compost
UNCC Bench-Scale Column Testing2011-2012
1000 mL synthetic stormwater solution fed to each column3.33 mg/L PO₄-P 1mg/L NO₃-N
(1-2) Batch Feed Method:Bottom valve closed for 12 hours of contacttime between the solution and the filtermedia
(3-4) Gravity Flow Method:Bottom valve closed for 30 minutes, then
opened to allow solution flow throughmedia
Removal RatePO₄-P 82% 97% 98% 58%
NO₃-N 65% 0% 0% 70%
NCSU ResearchJC Raulston Arboretum, Raleigh
June 2011 - July 2012
NCSU Substrate ResearchSecondary source runoff pond pumped to an irrigation pit
supplemented with:50 mg/L-1 N (supplied by dissolved ammonium sulfate, 21-0-0)
50 mg/L-1 P (supplied by dissolved diammonium phosphate 18-46-0)
Actual Nutrients in Stormwater + Fertilizer applied:80.9 ± 22.1 mg/L¯¹ N14.6 ± 5.5 mg/L¯¹ P
March 2011-July 2012
Season 1 Dormant Season Season 2
Leachate Averages N mg/L¯¹ P mg/L¯¹ N mg/L¯¹ P mg/L¯¹ N mg/L¯¹ P mg/L¯¹
‘Slate’ media 17 ~1.0 8 0.9 ~10 0.6
‘Sand’ media 30.1 ~3.0 13 ~3.0 ~10 0.6
‘Soil’ media 17 3.4 8 2.8 ~10 0.7
Life CycleC330 Resilience
Elon University
Hunt Softball Complex at Williamson Ave., Elon Univ. 2011-12
Elon University 2019
Northlake MallCharlotte NC
2005-2019
NCDOT ‘High Flow’Infiltration Basins
Manages hydraulic loadsStable – load-bearing for incidents and maintenanceResists over-compaction
Industrial StormwaterSludge Drying Bed Media
C330 Projects
The Read Building, Falls Church VA2007- present
Bioretention Cell between the Read Building and the Exxon station is 5’ deep
Transylvania Co. Public LibraryBrevard NC 2005 - present
Cells that are 4’-6’ deep in the NC mountains require a mediathat will not clog
Turf Bioretentionin WNC
Borg Warner, Arden NC
Empire Distributors, Arden NC
Richmond Hill ParkAsheville, NC
Spring 2009
Fall 2017 after 4” rain in the last 24 hours
NC ArboretumFletcher NC
2008-2019
C330 in Urban SCMs
Rain Catcher ProjectDurham NC
Downspout Disconnect2011 2017
For the Ellerbe Creek watershed
Urban RetrofitsTraffic Calming / Bioretention in Raleigh NC
Milburnie Road & Chatham Lane 2019
High Flow Tree WellsChatham Park, Pittsboro NC
NCSU Artists BackyardRaleigh 2011-2019
2015 BUBBA winner! Best Urban BMP outside the Chesapeake Bay watershed
Moore Square Raleigh 2019
Not bioretention,however, it isengineered with C330sand media to infiltrateand store moisture aswell as resist over-compaction
• Infiltration rates handle peak flows• Improves water quality• Long life cycle• Root zone re-aeration• Broad plant palette for designers• Manufactured in North Carolina• Nutrient trading? Bioretention and
constructed wetlands offer the highestreturns
C330 Bioretention Benefits
C330 Expanded Slate BlendedBioretention Media
FOB Aquadale, NC
$54.00 per ton @ 0.78 tons / CY= $42.00 per CY
One 25 ton bulk dump trailer =32 CY of C330 bioretention media
More Info:Debbie Stringer [email protected] Friedrich [email protected]