NHDOT/ACEC-NH 2016 Technical Transfer Conference April 7, 2016 Management of Mildly Contaminated Soil

What are “Mildly Contaminated Soils”? Soils with contaminant concentrations above naturally occurring background concentrations that are not:  virgin soils/rock from gravel pits and quarries  impacted by a discharge subject to NH Env-Or 600  hazardous waste Contaminant concentrations may be less than applicable regulatory standards. ** For NHDOT, concentrations may be above SRS/S-1 Soil Standards.**

Evolving Generator Knowledge  “Prior to 2010, we did not suspect the road shoulders were contaminated (except in areas of known spills).”  “Since 2010, hundreds of samples have been collected from dozens of projects…”  “…8 out of 10 projects…do not meet DEQ clean fill standards.”  PAHs, Metals, Petroleum 3

Where is NHDOT’s mildly contaminated soil? 4

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6 What NHDOT’s mildly contaminated soil is NOT: Not from spills Not from “point” source areas

If it can’t be used in a playground, it’s not clean.

Why now? Generator Knowledge NHDES Awareness

Determine acceptable approach to:  Comply with regulations  Limit liability  Protect human health and the environment  Be fiscally responsible Front Office Directive

What we’ve accomplished to date. Cost/ Logistics Regulations NHDES ORCB NHDES Haz Waste Remediation NHDES Solid Waste NHDES Commissioners NHDOT Operations NHDOT Project Development NHDOT BOE NHDOT Commissioners “The disposal of contaminated soils shall occur only at authorized facilities.” Env-Sw 903

Outcome – Solid Waste Rule Waiver (Pending)  NHDOT meets the rule intent, provided with flexibility for reuse  Operations: Work Instructions  Project Development: Soil Management Plans (SMPs) with Allowable Reuse Concentrations (ARCs)  NHDOT Administrators, employees, and consultants reference a formal document

12 What does it mean beyond NHDOT? MunicipalitiesPrivate Developers Other States

What does it mean to NHDOT? Avoid Operations – Design and construct E&S BMPs Project Development – Alignment considers MCS quantities Reduce Operations – Maintain E&S BMPs to limit waste generation Project Development – Modify design to mitigate export Reuse Operations – Reuse per WI… potential construction material? Project Development – Relocate per SMPs Both Divisions – Other uses with specific NHDES approvals Remove Both Divisions – T&D to reycle or landfill

Managing MCS is a cyclic process. Project Planning Preliminary Engineering Construction Engineering Operations

Borrow or Waste? Delineate? Reuse Potential Soil balance Geotechnical suitability Setbacks SMP / Pay Items BOE coordination Preliminary Engineering

Contracting Submittals – POP Means and Methods Sequencing Disposal Street wastes Documentation BOE coordination Construction Engineering

Next Steps 17 The DetailsNext Steps Modify proceduresInternal evaluation Identify potential reuse locationsGIS assessment Confirm distribution of MCS in ROW Research and field testing Assess impacts from background metals Evaluate potential lead-based paint presence OtherTBD

This approach will benefit NHDOT…  Protect public health and the environment  Promote environmental sustainability  Resolve cost uncertainty  Limit liability 18

Nikki Roy, P.G. Golder Associates (603) 668– 0880 Kate Emma Schlosser, P.E. Sanborn, Head & Associates, Inc. (603) 415 – 6167 Questions? Dale O’Connell, P.G. NHDOT Bureau of Environment (603) 271 – 6370