After construction or other major disruption, soil needs a little TLC. These quick tips, based on the Virginia DEQ stormwater design specification, cover the basics of soil restoration.

1. Recommendations from the Virginia DEQ Stormwater Design Specification No. 4
Soil Restoration
Using Compost

2. Soil restoration is an Environmental Site Design (ESD) practice
applied after construction, to deeply till compacted soils and
restore their porosity by amending them with compost. These soil
amendments can reduce the generation of runoff from compacted
urban lawns and may also be used to enhance the runoff
reduction performance of downspout disconnections, grass
channels, and filter strips.
Section 1 - VA DEQ Stormwater Design Specification No. 4

3. For simple rooftop disconnection
and filter strips, compost
amendment decreases annual
runoff by
50%

4. For grass channels, compost
amendment decreases
annual runoff by
30%

5. Total Phosphorus (TP) and Total
Nitrogen (TN) mass load removal is
the same:
50% for rooftop disconnection and
filter strips
30% for grass channels

6. Use compost:
Where soils are or will be compacted by grading
and construction

7. Use compost:
Where soils have low infiltration rates

8. Use compost:
When the area will be used to filter runoff
(downspout disconnections and grass channels)

9. Use compost:
Where mass grading will require more than a foot
of cut and fill across the site

10. Use compost:
For reforestation

11. Design criteria:
Soil testing pre-construction
• Determine soil properties to depth of 1 ft.
below the proposed amendment area
• Test for bulk density, pH, salts, nutrients
• Test every 5000 sq. ft.

12. Design criteria:
Soil testing 1 week after incorporation
• Ensures tilling or subsoiling has achieved
design depths
• Conduct in conjunction with final
construction inspection
• Test for nutrients, pH, soil organic matter

13. Compost specifications
• Manufactured by a member of the U.S. Composting
Council Seal of Testing Assurance (STA) program
• Pass through ½-inch screen
• pH between 6 and 8
• Less than 1% inerts by weight
• Organic matter content between 35% and 65%
• Soluble salt content less than 6.0 mmhos/cm
• Maturity greater than 80%
• Stability of 7 or less
• C:N ratio less than 25:1
• “Pass” on trace metal test
• Dry bulk density from 40 to 50 lbs./cu. ft.

14. Construction sequence
STEP 1: Prior to building, deep till to a depth
of 2-3 feet perpendicular to direction of flow
(not required for narrower filter strips)
FLOW
TILL

15. Construction sequence
STEP 2: After lot has been graded, 2nd deep
tilling to depth of 12-18 inches
FLOW
TILL

16. Construction sequence
STEP 3: Wait for dry
conditions before
incorporating
compost

17. Construction sequence
STEP 4: Incorporate compost at the
volumetric rate of 1 part compost to 2 parts
soil

18. Construction sequence
STEP 5: Level, then seed or sod

19. Construction sequence
STEP 6: If amending more than 2500 sq. ft.,
use erosion control measures

20. Maintenance - general
Educate landowners re: routine and long-term
maintenance

21. Maintenance - general
Utilize deed restrictions and other enforceable
mechanisms to ensure infiltrating areas are not
converted or disturbed
Include authority for property
inspection and corrective action

22. Maintenance - general
For more than 10,000 sq. ft. of reforestation, use public
right-of-way, deed restriction or
conservation/stormwater/drainage easements

23. Maintenance – 1st year
Months 1-6: inspect at least once after each
storm event exceeding ½-inch of rainfall
Spot reseed bare or eroding areas to stabilize with
grass cover

24. Maintenance – 1st year
Spot fertilize in the fall after the first growing season,
depending on amended soils test

25. Maintenance – 1st year
Water every 3 days for the first month; weekly during
first year (April-October, depending on rainfall)

26. Maintenance – ongoing
• No requirements for on-going maintenance
associated with compost amendments
• Optional: de-thatch every few years
to increase permeability

27. One product | Many benefits | Superior results
COMPOST WORKS

28. View more titles in the
Talking Compost series at
www.mcgillcompost.com
Production costs for this title were underwritten by McGill. Its use is permitted for educational purposes if
presented in its entirety and without editing or other alteration. ©McGill Environmental Systems of N.C.
Inc. Questions? Call McGill HQ at 919-362-1161 or use a contact form at www.mcgillcompost.com.