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Identifying and Sampling Hazardous Materials

WSDOT documents HazMat prior to construction as described on the Hazardous Materials Investigations and Documentation webpage. During construction it is usually a WSDOT contractor that identifies HazMat by sight or smell. In the event that a contractor encounters unanticipated HazMat, they stop work in the immediate area and notify the WSDOT PE (see Reporting Hazardous Materials).

Whether anticipated or not, WSDOT samples potentially hazardous materials to determine how to properly handle, manage, and dispose of them. WSDOT works with Ecology, local health departments, disposal companies, or others to determine the appropriate requirements for specific sampling activities. Discussed below are common practices WSDOT follows for different materials. WSDOT HazMat Specialists are available to offer additional support on any of these topics. WSDOT works with On-Call Consultants to complete sampling activities when in-house resources are unavailable.

Segregating Contaminated Material

During construction, WSDOT often has contractors segregate potentially contaminated soil, sediment, or water prior to collecting samples. These materials may be stockpiled or contained in roll-off boxes, storage tanks, 55-gallon drums, or other approved containers. Once WSDOT collects samples of the materials, contractors are not to add more material to the piles or containers. Segregated materials should not remain on a project site longer than 90 days unless it is determined that they are not problem or dangerous waste.
For soil or sediment that can be stockpiled, WSDOT’s minimum requirements include:

  • Placing the material on an impervious surface.
  • Covering the material as described in Section 8-01.3(5) of the Standard Specifications.
  • Keeping the stockpile covered at all times when not being worked.
  • Diverting water away from the stockpile area.
  • Collecting any water that does collect in the stockpile area for possible sampling and treatment prior to disposal.

In certain cases when sufficient space is unavailable on a project site, WSDOT may stockpile soils on other WSDOT-owned sites such as maintenance yards or borrow areas while awaiting characterization.
WSDOT controls airborne contaminants, such as dust laden with heavy metals, by using dust suppression methods such as water trucks and mulch.


Collecting Soil or Water Samples

WSDOT requires that qualified individuals perform all sampling using methods that provide results that are accurate and representative of site conditions. Depending on the sampling objectives, WSDOT collects samples according to the requirements of the selected laboratory, disposal facility, or disposal contractor and those of the local regulatory authority. Additional information about the following sampling topics is included below:

Qualifications of Sample Collectors

WSDOT policy is that only WSDOT HazMat Specialists or consulting environmental professionals who have the required training and experience (per WAC 296-843-200) are qualified to collect samples. These individuals possess the following:

  • 40-hour HAZWOPER certification & annual 8-hour refresher
  • 3 days of supervised on-site field experience
  • Annual respirator fit-testing

Scope of Work

A clearly written Scope of Work (SOW) defines the expectations and objectives of the sampling. WSDOT and consultants negotiate and agree on the terms of the SOW prior to beginning any sampling activities.

Sampling Plans – HASP, SAP, & QAP

WSDOT expects all field samplers to prepare and follow both a Health and Safety Plan (HASP) and a Sampling and Analysis Plan (SAP). The HASP should be reviewed and signed by all field personnel before the sampling begins.

A SAP outlines where and how samples will be collected as well as the number of samples that will be taken. The SAP also identifies specific laboratory requirements as well as the analytical methods that will be used. If field sampling deviates from the SAP, samplers record the changes in a field notebook.

When WSDOT samples petroleum contaminated soil for disposal or reuse, HazMat Specialists follow the Quality Assurance Plan for Field Screening and Disposal Characterization for Petroleum Contamination (pdf 1.4 mb).

Sampling Techniques

Field sampling typically involves the collection of soil and water samples. Sampling techniques depend on site conditions and whether samples are collected in-situ or from a stockpile or holding tank. Common techniques for in-situ sampling include direct push technologies, drilling boreholes or monitoring wells, and excavating test pits.

All samples are to be collected in a manner that produces usable and defensible data. Sample handling techniques are critical and include selecting correct sample containers, proper storage and transport, meeting hold time requirements, and following strict chain of custody procedures.

Analytical Labs

WSDOT uses and prefers that consultants use labs that are a part of the State’s Analytical Laboratory Services contract. At a minimum, Ecology certified labs (per Chapter 173-50 WAC) must perform the analysis. Selected methods for lab analysis should complement the objectives of the sampling and follow regulatory guidance.

Right of Entry

Prior to sampling, field staff must confirm that they have right of entry for the site. WSDOT project offices in conjunction with the Real Estate Services Office generally obtain this permission from the land owner.

Utility Locates

WSDOT usually requires field samplers to complete utility locates. The “Call Before You Dig” law requires anyone digging more than 12 inches into the ground to have underground utilities located at least two days before digging.

Labeling Sampling Waste

Place all sampling waste that shows obvious signs of contamination in secure containers while waiting for lab results. Containers must have a legible “Hazardous Materials/Analysis Pending” label including:

  • Project site
  • Container contents
  • Boring location and number
  • Date collected
  • Contact information

Once the waste is characterized, attach a “Hazardous Waste” or a “Non Hazardous Waste” label.


Sediment Sampling

WSDOT projects like ferry terminals or bridge crossings that occur in marine or freshwater may need to evaluate and characterize sediment for chemical contamination. Sediment sampling and testing are regulated by Ecology’s Sediment Management Standards (SMS), Chapter 173 204 WAC.

If a WSDOT project involves dredging, WSDOT uses the Dredged Material Evaluation and Disposal Procedures User Manual, July 2015 (pdf 2.75 mb) . The manual is published by the Dredged Material Management Program (DMMP), an interagency group led by the US Army Corps of Engineers Dredged Material Management Office (DMMO). The DMMP provides criteria for in-water disposal of dredged sediment. If the sediments are not suitable for open-water disposal, they will need to be disposed of at an appropriate upland disposal facility.

Asbestos-Containing Materials (ACM)

Asbestos is a known carcinogen that may be found in many building materials including:

  • Residential and commercial structures built before 1981
  • Thermal system insulation
  • Various decorative spray-on textures and fire proofing
  • Floor coverings
  • Siding
  • Adhesives
  • Roofing materials
  • Utility pipes and conduit
  • Thousands of other building materials and applications

Since local Clean Air Agencies generally regulate asbestos removal, WSDOT follows the applicable procedures and ensures the following prior to the demolition of a structure (including bridges):

  • An accredited Asbestos Hazard Emergency Response Act (AHERA) Building Inspector performs an Asbestos Survey.
  • The Local Clean Air Agency receives notification of demolition activities.
  • An abatement contractor removes any asbestos-containing material (ACM) prior to demolition.
  • The abatement contractor transports ACM to a permitted, lined landfill for disposal.

WSDOT performs asbestos surveys on buildings and other structures prior to placing construction projects on Ad for bidding in accordance with WAC 296-62-07721. Depending on availability, WSDOT HazMat Specialists perform the asbestos surveys for WSDOT projects. Otherwise, WSDOT uses other state agencies or consultants.

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Lead-Based Paint (LBP)

Lead-based paint (LBP) was commonly used in the past on exterior painted wood, metal, and concrete, as well as interior window frames and doors. WSDOT often deals with LBP during bridge painting projects and demolition work. For LBP in bridge painting projects, WSDOT Contractors follow the appropriate Standard Specifications. Prior to building demolitions WSDOT performs lead surveys to address worker health and safety issues as well as to assist with determining disposal requirements.

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Underground Storage Tanks (USTs)

If WSDOT staff or a contractor finds an unknown tank during construction, they immediately notify (pdf 42 kb) the PE who will initiate ECAP. WSDOT must notify Ecology of releases from underground storage tanks (USTs) within 24 hours (per WAC 173-340-450). An outline of the notifications and general steps WSDOT follows when removing USTs is available on the Reporting HazMat web page.

WSDOT prefers to remove underground storage tanks (USTs) instead of closing them in place. When a UST is on a property that WSDOT will purchase for a construction project, all efforts are made to remove the UST before the real estate transaction is complete.

All UST removals, even those that may be exempt from Ecology’s UST Regulations (Chapter 173-360 WAC), require a site assessment by a certified UST Site Assessor. For specific instructions on where and how to collect samples, WSDOT follows the 2003 Ecology document “Guidance for Site Checks and Site Assessments for Underground Storage Tanks”.

WSDOT has HazMat Specialists who are certified UST Site Assessors and can normally assist project offices within 1-2 weeks of notice. Please contact a HazMat Specialist for more information. UST removals generally cost $4000 to $30,000 for unregulated tanks and $8,000 to $50,000 for regulated tanks. 

Additional Information About

  • Property Appraisals during Real Estate Transactions that have above or underground storage tanks (WSDOT Right of Way Manual, Chapter 4-4.4(E)(1)(g)).