Cedar Grove Landscape & Construction Serviceshttp://www.cedar-grove.com/services.asp

Specifying Compost and Soils for BMP T5.13 Soil Quality and Depth,

Bioretention Soil Mixes, Green Roofs and other applications

A Dual Perspective

Howard StennSustainable Business Development

Howard StennSpecification Writer

CODRS

Contractors Often Don’t Read Specs

CDRS.

KISS Keep It Short and Simple

New Cedar Grove T5.13 Spec

Keep It Simpler: Specify just one option

Original BMP T5.13 Spec (partial)

Keep The Details SimpleAnd Get What You Want on the Job

Use Regulatory Standards to keep spec concise and ensure quality‘Compost’ per WAC 173-350-220: Meets standards for heavy metals,

human pathogens, physical contaminants.

Shows facility complies with environmental & health regulations.

Can exclude ‘Type IV Feedstocks’ (mixed wastes)

Specify ‘Approved’ Products – or ‘Equivalent’ Define ‘Equivalent’ with tests

/parameters that make it difficult to substitute low-quality product

Use Industry Quality Standards… US Compost Council ‘STA’ includes

standards for pH, salinity, plant germination, stability, organic matter content, particle size distribution.

Be Specific About Topsoil Define “sandy loam” per USDA (for

sensitive uses) If you want clean loam, specify sand (at

least on top lift) Use appropriate specs. PGA greens

standards not required for most lawns.

Using “Custom Calculated” Amendment Rate can save lots of $$$

King County Compost and Topsoil Calculator uses the the standard method developed for WDOE. http://your.kingcounty.gov/solidwaste/compost_calculator.htm

Uses tests of % organic content & dry weight of soil & compost

Soils for Salmon website calculator allows more variableshttp://www.soilsforsalmon.org/excel/Compost_Calculator.xls

Provide a Simple Summary on Plans

Put essential soil specs on plan NOTES sheet, details in specs.

Put NOTES in front of plan set, to be sure.

MSSAAEMake Sure Specs Are Achievable & Effective

Specify either mix characteristics OR performance standards, not both. Soil properties are not as predictable as other construction materials.

Use commonly accepted standards to save time, money and frustration. Novel specifications result in onerous testing requirements and expensive mixes. Make sure they are justified.

Specifying Green Roof Soils

Several mixes and specifications, but no standards yet.

Cedar Grove has popular Green Roof and “Rooftop / Lightweight” mixs that can be specified by name, but the mix is proprietary.

HINT: There’s not a lot of compost in them

Maple Valley Facility

Everett Facility

Cedar Grove Landscape & Construction Serviceshttp://www.cedar-grove.com/services.asp

Standard Mixes & Specifications for: Topsoil Blends meeting BMP T5.13 for Turf

& Planting Beds Bioretention Mix meeting WSU-SPU spec Rain Garden Mix for small projects Green Roof & Lightweight / Rooftop Mixes Compost-based erosion & sediment controls:

Filter Socks and Berms, Erosion Control Blankets, Living Walls.

Recycling Services Fill soils export & import Land clearing and clean wood

Planning & Compliance Assistance