Testing

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Section 8.2 - 8.9 content text (only) Appendix C as A SCROLLING DOCUMENT!!!

Mention training courses

Soil Characterization Testing[edit]

The soil component of an LID BMP contributes substantially to its stormwater treatment performance and overall function. If the soil is overly compacted or very finely textured, it may drain too slowly. If the soil is highly organic or contains excessive amounts of chemical fertilizer it may contribute to nutrient loads to receiving waters rather than reduce them. If the soil is too shallow it may not provide adequate treatment of contaminated stormwater or may not support healthy vegetation. Whether it be the engineered filter media of bioretention cells, the growing media of green roofs or the topsoil of enhanced swales, vegetated filter strips and soil amendment areas, it is important that the soil provide a healthy growing environment for plantings while being within design specifications for key parameters specific to the type of BMP.

It is most important to sample and test soil characteristics as a part of Construction and Assumption inspections, to confirm the BMP has been constructed with materials that meet design specifications and that installation of the soil component is acceptable. Testing to confirm that the material meets quality specifications (i.e., particle-size distribution, organic matter, pH, cationic exchange capacity, nutrients and soluble salts) needs to be completed prior to it being delivered to the construction site. Testing to confirm that installation of the soil component is acceptable (i.e., depth and compaction) should be performed after the installed material has been allowed to settle for at least two (2) weeks, and prior to planting.

Sampling and testing is also recommended as a part of Verification inspections, to determine if the BMP is being adequately maintained and if soil characteristics are still within acceptable ranges. It may also be done as part of Forensic inspection and Testing (FIT) work to help diagnose the cause of poor vegetation cover, drainage or treatment performance and decide on corrective actions.


Critical soil characteristics, acceptance criteria and tests by LID BMP type

LID BMP Type

Soil Characteristic

Acceptance Criteriai

Test
Bioretention / Bioswales / Dry swale
Textureii Loamy Sand or Sandy Loam; 70 to 88% sand-sized particles; 12 to 30% silt- and clay-sized particles; <20% clay-sized particles. Particle-Size Distribution (PSD), or % Sand/Silt/Clay (i.e., Soil Texture) plus Sand Fraction
Organic Matter (OM) 3 to 10% by dry weightii Walkley-Black method when OM <7.5% or Loss On Ignition (LOI) method when OM ≥7.5%iii
Soil pH 6.0 to 7.8 pH of a Saturated Pasteiii
Cationic Exchange Capacity (CEC) >10 meq/100 g Cationic Exchange Capacity Test
Phosphorusiv 12 to 40 ppm Extractable Phosphorus
Soluble Saltsv ≤2.0 mS/cm (0.2 S/m) Electrical Conductivity of a Soil-Water Slurry (2:1 water to soil ratio by volume)iii
Depth +/- 10% of design specification Soil Cores, Test Pits or Cone Penetration Tests
Compactionvi Surface Resistance: ≤110 PSI; Sub-surface Resistance: ≤260 PSI Bulk Density: ≤1.60 g/cm3 Cone Penetration Tests or Bulk Density Tests
Permeability i ≥25 mm/h (KS ≥ 1 x 10-5 cm/s); and i ≤203 mm/h (KS ≤ 0.02 cm/s). Surface Infiltration Rate Tests
Enhanced swale (topsoil)
Texture Same soil texture classification as specified in the final design or recorded on the as-built drawing Particle-Size Distribution (PSD), or % Sand/Silt/Clay (i.e., Soil Texture) plus Sand Fraction
Organic Matter (OM)ii 5 to 10% by dry weight Walkley-Black method when OM <7.5% or Loss On Ignition (LOI) method when OM ≥7.5%iii
Soil pH 6.0 to 7.8 pH of a Saturated Pasteiii
Phosphorusiv 12 to 40 ppm Extractable Phosphorus
Soluble Saltsv ≤2.0 mS/cm (0.2 S/m) Electrical Conductivity of a Soil-Water Slurry (2:1 water to soil ratio by volume)iii
Depth +/- 10% of design specification Soil Cores, Test Pits
Compaction Surface Resistance: ≤110 PSI; Sub-surface Resistance: Use soil texture class and Table 8.3 to determine maximum acceptable value; Bulk Density: Use PSD to interpolate maximum bulk density value from Figure 8.7. Cone Penetration Tests or Bulk Density Tests
Permeability i ≥15 mm/h (KS ≥ 1 x 10-6 cm/s) Surface Infiltration Rate Tests
Vegetated filter strips and Soil Amendment Areas (topsoil)
Texture Same soil texture classification as specified in the final design or recorded on the as-built drawing Particle-Size Distribution (PSD), or % Sand/Silt/Clay (i.e., Soil Texture) plus Sand Fraction
Organic Matter (OM)ii 5 to 10% by dry weight Walkley-Black method when OM <7.5% or Loss On Ignition (LOI) method when OM ≥7.5%iii
Soil pH 6.0 to 7.8 pH of a Saturated Pasteiii
Phosphorusiv 12 to 40 ppm Extractable Phosphorus
Soluble Saltsv ≤2.0 mS/cm (0.2 S/m) Electrical Conductivity of a Soil-Water Slurry (2:1 water to soil ratio by volume)iii
Compaction Surface Resistance: ≤110 PSI; Sub-surface Resistance: Use soil texture class and Table 8.3 to determine maximum acceptable value; Bulk Density: Use PSD to interpolate maximum bulk density value from Figure 8.7. Cone Penetration Tests or Bulk Density Tests
Permeability i ≥15 mm/h (KS ≥ 1 x 10-6 cm/s) Surface Infiltration Rate Tests
Green roof (growing media)
Texture See product vendor or BMP designer for specifications Particle-Size Distribution (PSD), or % Sand/Silt/Clay (i.e., Soil Texture) plus Sand Fraction
Maximum Media Density See product vendor or BMP designer for specification Maximum Media Density Test (ASTM E2399/E2399M-15)
Water Storage Capacityvii Extensive: ≥35% by volume / Intensive: ≥45% by volume Both part of Maximum Media Density Test (ASTM E2399/E2399M-15)
Air-Filled Porosityvii ≥10% by volume Part of Maximum Media Density Test (ASTM E2399/E2399M-15)
Permeability, Saturated Media See product vendor or BMP designer for specification Part of Maximum Media Density Test (ASTM E2399/E2399M-15)
Organic Matter See product vendor or BMP designer for specification Walkley-Black method when OM <7.5% or Loss On Ignition (LOI) method when OM ≥7.5%iii
Soil pHviii 6.5 to 7.8 pH of a Saturated Paste
Soluble Saltsviii ≤0.85 mS/cm (0.085 S/m) Electrical Conductivity of a Saturated Media Extract (SME)solution
Phosphorusix 2.2 to 40 ppm Electrical Conductivity of a Saturated Media Extract (SME)solution
Notes
i Values represent acceptable ranges for established BMPs (i.e., in operation for 3 years or more). For Construction and Assumption inspections, final design and soil or media product specifications and permissible tolerance ranges should be used as the acceptance criteria, which may be smaller ranges than the values in this table.
ii Suggested range for diagnosing suspected problems with drainage function, vegetation cover or vegetation condition for established BMPs constructed with filter media that meets recommended guidelines (CVC & TRCA, 2010)[1]. For proprietary filter media products, different ranges may be acceptable. Product specifications should be provided by the media supplier. Test results should be compared to the media supplier’s specifications and permissible tolerance ranges
iii Based on Ontario Ministry of Food and Rural Affairs’ Soil Fertility Handbook guidance on soil fertility testing for crop production (OMAFRA, 2006)[2].
iv Based on Minnesota Pollution Control Agency (MPCA, 2015) for minimum to sustain plant growth and Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA, 2014) for a maximum to avoid unnecessary fertilization that would have low or no effect on plant health.
v Based on the threshold for non-saline soils (Whitney, 2012).
vi Interpolated value from Figure 8.7 based on a sandy loam soil containing at least 70% sand-sized particles.
vii Based on German green roof standards (FLL 2008). Specifications will vary depending on the green roof growing media product. Product specifications should be provided by the media supplier. Test results should be compared to the media supplier’s specifications and permissible tolerance ranges.
viii Based on Penn State University Center for Green Roof Research (Berghage et al. 2008).
ix Based on Penn State University Center for Green Roof Research (Berghage et al. 2008) for the minimum to sustain plant growth and Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA, 2014) for the maximum to avoid unnecessary fertilization that would have low or no effect on plant health.


Acceptable Soil Cone Penetrometer Readings (Soil & Texture Class)

Surface Resistancei
'Sub-surface Resistancei
All Soil Textures Sandy (includes loamy sand, sandy loam, sandy clay loam and sandy clay) Silty (includes loam, silty loam, silty clay loam, and silty clay) Clayey (includes clay loam and clay)
≤ 110 PSIii ≤ 260 PSI ≤ 260 PSI ≤ 225 PSI
≤ 7.7 kg/cm2 ≤ 18.3 kg/cm2 iii ≤ 18.3 kg/cm2 ≤ 15.8 kg/cm2
≤ 758 kPaiv ≤ 1793 kPa ≤ 1793 kPa ≤ 1551 kPa
Notes
i Adapted from Gugino et al. (2009)[3]
ii PSI = pounds per square inch (lb/in2)
iii kg/cm2 = kilogram per square centimetre.
iv kPa = kilopascals

ADD FIGURE 8.7 IN THE SOIL ACCUMULATION SECTION BELOW!!!

Sediment Accumulation Testing[edit]

Surface Infiltration Rate Testing[edit]

Natural or Simulated Storm Event Testing[edit]

Continuous Monitoring[edit]

Green Roof Irrigation System Testing[edit]

Green Roof Leak Detection Testing[edit]

Cistern Pump Testing[edit]

References[edit]

  1. CVC and TRCA, 2010. Low Impact Development Stormwater Management Planning and Design Guide. Version 1.0. https://cvc.ca/wp-content/uploads/2014/04/LID-SWM-Guide-v1.0_2010_1_no-appendices.pdf
  2. OMAFRA. 2006. Soil Fertility Handbook Publication 611. Guelph, Ontario, Canada. http://www.omafra.gov.on.ca/english/crops/pub611/pub611.pdf.
  3. Gugino, B.K., Idowu, O.J., Schindelbeck, R.R., van Es, H.M., Wolfe, D.W., Moebius, B.N., Thies, J.E., and Abawi, G.S. 2009. Cornell Soil Health Assessment Training Manual, Edition 2.0, 2009, Cornell University, College of Agriculture and Life Sciences, New York State Agricultural Experiment Station(NYSAES), Geneva, New York. ISBN 0-9676507-4-7. https://www.canr.msu.edu/foodsystems/uploads/files/cornell_soilhealth.pdf