Risk Assessment of Disposal Options for Street Debris and Detention Basin Sediments Presented by Matthew Looft Kendall Clare McPeters Danielle Roy Sarah Ullman Lara Vowles

Project Background Winooski has limited and costly collection techniques for street sweeping debris and catch basin sediments Interested in beneficial re-use alternatives for these sediments

Our Response… Street debris and catch basin sediment analysis Alternatives for beneficial re-use that stress environmental integrity Case Studies of re-use successes Simple effects analysis of these alternatives Recommendations

Sample Analysis Winooski and South Burlington comparison of metal concentrations for Street Sweeping Debris Metal Winooski Sample Concentration (mg/kg) S. Burlington Sample Concentration Range (mg/kg) Computed Maximum TCLP Concentration of S. Burlington Samples (mg/L) Regulatory TCLP Concentration (mg/L) Arsenic Barium Cadmium < 1.13*< < 0.960< Chromium Lead 23.7* Mercury < 0.302< Selenium <3.22*< < 1.37< Silver <1.61*< < 1.37< Source: Pioneer Environmental Associates, LLC., ENDYNE, INC.

Sample Analysis Continued total petroleum hydrocarbons (TPH) TPH (mg/kg)TPH Maximum Allowable Amounts (mg/kg or ppm) Street Sweeping Sediments 90.81,000 Catch Basin Sediments 82.61,000 Source: ENDYNE, INC., Vermont Agency of Natural Resources Winooski TPH Concentrations and Regulatory Levels

Results of Sample Analyses TPH and RCRA metal concentrations well below Vermont ANR Guidelines for  Petroleum Contaminated Soil and Debris  Hazardous Waste Management Regulations *Beneficial Re-Use Possible!

Possible Risks if Above ANR Guidelines TPH: Total Petroleum Hydrocarbons –Minimal exposure is unavoidable –Acute exposure can cause adverse reactions in the blood, skin, eyes, legs (paralysis), immune system –Can linger in soils, film on surface waters, or settle into bottom sediments

Possible Risks Continued… RCRA 8 Metals: arsenic, barium, cadmium, chromium, lead, mercury, selenium, silver –Bioaccumulation in plant and animal tissue –Threats to microorganisms in soil ecosystems –Severe allergic reactions –Carcinogenicity –Damaging effects to nervous system and/or brain of fetuses –DNA damage

Environment and Human Health Risks

Alternative Reuses if Above ANR Guidelines Compost –Biologically decomposes organics –Thermal desorption of some volatile organics –Simple process (windrows, turning, wetting) –Valuable topsoil or mulch as end product Biological Degradation –Inoculating with soil bacteria, mycelial fungi to enhance decomposition of pollutants and residues

Suggested Alternatives for Winooski “No action” – Continued disposal in landfills Daily cover at landfills Compost additive Road sand Containment/absorption material Roadway fill or backfill Sub-fill for potholes Replacement for raw material in concrete or asphalt Land reclamation

Case Studies Bloomington, MN: 100% reduction of landfilling sweepings by reusing as road sand Bangor, ME: reuse as clay composite for rec. trails Worcester, MA: development of guidelines for finding reuse alternatives (Chelsea Center) Colorado Springs, CO: 100% reduction of landfilled CB sediments by facility for dewatering, screening, composting

Reuse Initiatives Possibility for an in depth study on beneficial reuse of street sweepings and catch basin sediments to happen at UVM to benefit the Burlington, Winooski, Williston communities?

Effect Analysis for Proposed Alternatives EnvironmentalEconomicSocial No action NPN Landfill cover MNM Recreation Trails PMP Compost Additive NPP Road Sand MPP Contaminant/ Adsorption material PPM Construction fills PPP To fill in bodies of water NPN Crash Attenuation barriers PPP

High Priority Roads Close to Water bodies North

Community Collaboration and Beyond… SAND Model Sediment Accumulation Nexus District –Regional Collection Community Sediments Analysis Shred/Sort Wash Screen Storage –Trade for credits –Sell to business or public

Beneficial Reuse Reapplication for transportation use Mixed with clay for recreational paths at Gilbrook Park Landfill daily/weekly cover for Chittenden Solid Waste District Compost additive at the Intervale Roadway fill or backfill at construction sites Fill in crash attenuation barriers along Interstate 89 Containment/absorption medium for hazardous material spill response

On Site Remediation Composting –Biological decomposition of organics –Thermal desorption of volatile organics Biological Degradation –Nutrient cycling –Waste and residue decomposition –Detoxification of environmental pollutants Immobilization –Aggregates in concrete or asphalt

Recommendations Beneficial Reuse will -Be more effective than current practices -Pay for itself over time -Reduce ‘new sand’ by % *Winooski should initiate a local beneficial reuse program to serve as an example for a county wide SAND program