February 10, 2012 Marcus Zbinden, Environmental Specialist III

1. Carver County’s Comments to MPCA Source Separated Organic Compost Facility Rules February 10, 2012 Marcus Zbinden, Environmental Specialist III Kellie Kish, Environmental Specialist I

2. Carver County Organics Demonstration Site Arboretum Site I Mayer Site Arboretum Site II

3. Demonstration Site Comparison

4. Arboretum II (SET) Site: • Size- 2.5 acres • Site pad – All weather surface of 3 inches of 1½ minus limestone and 3 inches class V • Lester Kilkenny clay loam soil Profile: • 0 – 7 inches: Clay loam • 7 – 38 inches: Clay loam • 38 – 80 inches: Loam • Depth to seasonally saturated soil is 12 inches • Depth to water table is >80 inches (National Cooperative Soil Survey)

5. Installing Water Collection Tubes

6. Lysimeter Placement at Arboretum II Site: Oct. 11th - 13th: 0.74” rainfall event • Only 16% of lysimeters under piles had some liquid present but none had sufficient volume to be analyzed.

7. Contact Water Analytical Results (Metals) * Landfill mid-range and high-range data was taken from Land Treatment of Landfill Leachate. MPCA, April 2011. ** No HRL has been set for these elements as they are not found in source waters. *** The HRL for Arsenic was changed from 50 ug/L to 10 ug/L in 2006. **** Silver was sampled at ARB I and Mayer sites only.

8. Agronomic Constituents * Landfill mid-range and high-range data was taken from Land Treatment of Landfill Leachate. MPCA, April 2011. ** Potassium sampled at ARB I only. *** TKN – 2 samples from ARB II were not analyzed correctly for Nitrates by PACE – both returned ND results.

9. Chromium & Copper (ppm) TDS & TSS * Landfill mid-range and high-range data was taken from Land Treatment of Landfill Leachate. MPCA, April 2011.

10. Residential Organics Collection

11. Residential Source Separated – Co-Collected • September 26, 2011 load from Edina -VierkantWaste Sort • Organics 2,318 lbs. 6 yards 21% (by weight) • Yard Waste 8,800 lbs. 12 yards 78% (by weight) • Contamination 43 lbs. .17 yards <1% (by weight)

12. Commercial Organics

13. Carver County Comments on Rules Subp 3. B. Operator may establish a source-separated organics waste composting facility within 5 feet of water table. Recommendation: If aquifer is that of MN Rule 4725.0100, Supb. 21, Carver County accepts rule change. MN Rule 4725.0100, Subp. 21: “Aquifer” means a stratum of saturated, permeable bedrock or unconsolidated material having a recognizable water table or potentiometric surface which is capable of producing water to supply a well.

14. Carver County Comments on Rules Supb. 8. F. The active composting, curing and storage areas for immature compost must be located on an impervious surface… 1.Contact water test results from organics demonstration sites demonstrate that there is no contact water leaving the site that exceed testing standards for drinking water. 2. Contact water levels in lysimeter installed at the demonstration site supports industry findings that compost piles absorb most moisture from rain events and allow little to enter surface water containment area or infiltrate into sub-soils. Recommendation: • Tipping Pad - 6 inches of Class V as a minimum • Active composting, processing and curing areas – all weather working surface which is defined as any surface that allows the ability of equipment and hauling trucks to access site for 365 days of operations.

15. Estimated Pad Costs 1 acre = 43,560 ft2 2’ Class V to cover 1 acre = 2,420 tons

16. Carver County Comments on Rules 7035.2555 Subp. 3. Minimum of 500 feet horizontal separation distance from the facility to the nearest residence, place of business or public contact area. • There is no distance requirement for either solid waste compost facility or yard waste compost facilities; there should not be a mandated distance for SSO facilities. • Facilities vary in size, capacity, feedstock, topography and zoning. Recommendation: • Allow local units of government to establish distance requirements on a case by case basis. • Provide distance requirement in guidance document.

17. Compost Data Team ReportOctober 30, 2009 Background: • Data Team comprised of 4 metro county staff and 2 MPCA staff led by Allen Dotson and Geoffrey Strack. • Team was formed to complete revision of MPCA’s Demonstration Agreement and review other state regulation on composting. Conclusions: • Data from demonstration projects may help answer questions regarding contamination in contact water. • May be reasonable to provide flexibility on composting pad requirements, varying for example with site-specific soils types, feedstock types, location and scale of operation.

18. Recommended Tiers: I. Backyard Composter No MPCA permit or training required II. Yard Waste Permit by Rule • Small Site Recommend increase to 100yds3 annually or equivalent weight IV. Residential Source Separated V. Commercial Source Separated 0ther material as approved by MPCA • MSW • Regulation and permitting requirements become more stringent as the types or tonnages of organics material increases. • Residential co-collected sites should have reduced horizontal distance requirement and potentially a less restrictive pad requirement. • Residential co-collected sites should also have less strict operating procedures such as mixing material by the end of the day versus immediate cover and/or processing for commercial facilities.

19. Potential Compromises Allow less stringent pad requirement and separation distance if the following conditions are met: • Site operator must take soil sample under processing and curing area prior to site development and periodically thereafter to ensure no contamination of ground water is occurring. • Facility operator could also elect to install lysimeters and take periodic samples. • If finished compost or contact water tests show issues, require additional testing or mediation.