Plant ecotoxicity tests were conducted on SWM pond sediment collected from four stormwater management ponds. The positive plant growth results supported beneficial use as topsoil amendment material as a cost effective and environmentally sustainable alternative to landfill disposal.

1. 2015-2017 Stormwater Management Pond
Sediment Beneficial Use
Plant Ecotoxicity Study Results
Presented by: Francine Kelly-Hooper, PhD
Presented to: Southwestern Ontario Municipal Stormwater Group
May 26, 2016

2. 2015-2016 Research Partners & Plant Growth Studies
• City of Kitchener (Melissa Ryan) – 2015 plant growth study
• City of Waterloo (Angela MacLean) – 2016 plant growth study

3. Ontario Excess Soil BMP Approach to Beneficial Use of SWMF Sediments
- Described in Regulatory Section of 2016 TRCA Manual -

4. Excess Soil Risk Management Evaluation
Waste Disposal versus Beneficial Use
Question #2: Does the sediment pass O. Reg. 153/04 Table 1
(background) soil standards?
Fail
Question #3: Does the sediment pass O. Reg. 153/04 Table 2,3
(risk) soil standards for residential/parkland/institutional use?
Consider re-use options
for residential/parkland/
institutional sites
Fail Requires hazardous
waste disposal
Question #4: Does the sediment pass O. Reg. 153/04 Table 2,3
soil standards for industrial/commercial/community use?
Consider re-use options
for industrial/commercial/
community use
Fail
Fail
Pass
Pass
Question #1: Does the sediment pass the O. Reg. 347 leachate
test?
“Inert” – unregulated
disposal/use
Pass
Pass
Non-hazardous waste disposal

5. Likelihood that Residential SWMF Sediments will Require
Regulated Waste Management Approval?
F3 petroleum hydrocarbon (PHC) exceedences
of O.Reg.153/04 Table 1 soil standards

6. 2005-2015 Sediment Quality Survey Results
61 Residential SWMFs
100% of leachate results met non-hazardous waste
disposal requirements (12 SWMFs tested)
98% of F3 PHCs exceeded Table 1
52% of PAHs exceeded Tables 2 & 3
16% of SAR and 17% of metals exceeded Tables 2 & 3

7. Landfill Disposal versus Beneficial Use Risks Evaluations

8. Basis of O.Reg. 153/04 Table 1, 2, 3 soil standards
Table 1 background soil standards
- Assumes pre-colonial (pristine) concentrations
Table 2&3 toxicity standards
- May not consider contaminant sources and/or bioavailability

9. Examples of PHC & PAH Sources with Different Bioavailabilities
Fresh gasoline and diesel
Weathered asphalt & coal tar sealant, tires, engine emissions
More
Bioavailable
Less
Bioavailable

10. 1) Francine Kelly-Hooper’s PhD research project (2007-2012)
2) Kelly Hooper Environmental and CH2M SWMF Sediment Survey (2005-2016)
3) CH2M Chemical Mass Balance Modelling PAH Source Study (2015)
Conclusion Drawn From 3 Studies

11. Relevance to O.Reg. 153/04 Soil Standards?
Ecotoxicity studies may demonstrate low bioavailability
and toxicity risks of PHCs and PAHs in SWMF sediments.
New guidelines for SWMF sediment beneficial use
versus disposal evaluations may resolve this issue.

12. 21-day plant test: seedling emergence,
shoot/root length and weight
Environment Canada Soil Toxicity Test Methods

13. 2016 and 2017 SWMF Sediment Plant Growth Experiments
21-Day Growth Tests
• #1 – Victoria Park Lake
• #2 – SWMF Wetland 46
• #3 – Silver Lake
• #4 – SWMF Wetland 53

14. Plant Growth Experiment Objective
To determine if turf grass species would successfully grow in
SWMF sediments with contaminant levels that exceeded one or
more of the following O.Reg. 153/04 Table 1, 2, 3 soil standards:
*SWMFs with elevated trace metal concentrations were excluded due
to land application bioaccumulation risks.

15. Targeted Topsoil Amendment Beneficial Use
- Municipal Roadside Planting Programs -
Too Much Sediment
with Costly Landfill
Fees
Too Much Unwanted
Compost Takes Up
Landfill Space
Cities Need Topsoil
for Routine
Roadside Rehab

16. Targeted Topsoil Amendment Beneficial Use
- Municipal Roadside Planting Programs -
Too Much Sediment
with Costly Landfill
Fees
Too Much Unwanted
Compost Takes Up
Landfill Space
Cities Need Topsoil
for Routine
Roadside Rehab
Sediment + Compost
= Topsoil Cost Savings

17. 21-Day Plant Growth Experiment Designs
Control –
Miracle Grow
Soil
Silver Lake
Sediment +
Compost
• 10 fescue
seeds/pot
• 3 replicates/
treatment
Wetland 53
Sediment +
Compost
Waterloo
Treatments
• 10 ryegrass
seeds/pot
• 3 replicates/
treatment
(1)
(2)
(3)
Control –
Miracle Grow
Soil
VP Lake
Sediment +
Wood Chips
• 20 fescue + ryegrass
seeds/pot
• 5 replicates/treatment
Wetland 46
Sediment +
Compost
Wetland 46
Sediment (No
Compost)
Kitchener
Treatments
(1)
(2)
(3)
(4)

18. Laboratory Topsoil Report
Jack Legg, Certified Crop Advisor provided compost mixing ratio recommendations
This topsoil amendment beneficial use approach was developed through several years of discussions between
Jack Legg (SGS AgriFood), Dale McComb (OMAFRA) and Francine Kelly-Hooper (CH2M)

19. VP Lake Silver Lake WL 46 WL 53 Municipal
Compost
Miracle
Grow Soil
Table 2 soil
standard for
commercial/
industrial
property use
Boron (hot water extractable) Concentrations for Unmixed
Sediment, Compost and Potting Soil
SWMF Sediments Compost & Soil
HWEBoron(mg/kg)

20. VP Lake Silver Lake WL 46 WL 53 Municipal
Compost
Miracle
Grow Soil
Table 1 soil
standard for
all property
uses
F3 Petroleum Hydrocarbon Concentrations for
Unmixed Sediment, Compost and Potting Soil
FALSE PHC detections in
clean compost and soil
Asphalt & coal tar sealcoat are
main sources of F3 PHCs
Compost & SoilSWMF Sediments
F3PHCs(mg/kg)

21. 21-Day Plant Growth Results

22. 0
2
4
6
8
10
12
14
Plant Shoot and Root Lengths
City of Kitchener Results
Shoots(cm)Roots(cm)
0
5
10
15
20
25
WL46
Compost
Miracle
Grow
VPL
Wood
Chips
100
WL46
Miracle
Grow
0
2
4
6
8
10
12
14
16
18
Shoots(cm)
City of Waterloo Results
Miracle Grow Silver Lake Pond 53
0
5
10
15
20
25
Roots(cm)
Miracle
Grow
Silver L
Compost
WL53
Compost

23. Sediments were
non-toxic to the
test plants
Bottom Line?
But what about food chain
transfer risks?

24. Next Steps?
Expand plant growth studies to include
earthworm ecotoxicity studies as well.
Continue to collaborate with the MOECC
and OMAFRA on field scale pilot studies.

25. g{tÇ~ lÉâg{tÇ~ lÉâg{tÇ~ lÉâg{tÇ~ lÉâ
Francine Kelly-Hooper, PhD
CH2M
Francine.kellyhooper@ch2m.com
C:519-502-3122