Procedure Overview

One benefit of performing environmental site assessments early in project development is that unanticipated contamination encountered during construction is potentially minimized. When contamination is unexpectedly encountered in a construction project, potential negative consequences include:
  • Injury to workers and the public
  • Damage to equipment and property
  • Delays in construction, damage claims by the contractor
  • Additional costs for the procurement of consultant services, specialty contractors, and field changes.
If hazardous materials are discovered during construction, project construction may be delayed until a lengthy, complex process of investigation produces acceptable measures to handle the contamination. Also, if the unanticipated encounter with hazardous material contamination aggravates the problem, such as causing a further release of contaminants, then TxDOT may become partially liable for the environmental consequences and required cleanup of the release.
When hazardous materials are identified during earlier phases of the project development and it is determined that cleanup is not feasible prior to construction, then preventive action may be incorporated into the construction project. Preventive action refers to cleanup and related activities required to affect the construction of the highway project. Corrective action refers to activities required by state or federal regulations to be performed by a responsible party to protect human health and the environment.
See Chapter 4, Section 4, “
Contamination Factors and Considerations during Construction
,” for a list of options for cost effectively and efficiently handling contamination on a project.
TxDOT Standard Specifications do not provide for the inclusion of analytical testing, preventive action or management of contaminants in the construction contracts, since these are outside the scope of "Highway Construction." If such preventive measures are required of the prime construction contractor or specialty subcontractor (Option 5), they should be included by special provision. See Chapter 4, Section 5 “Plans, Specifications & Estimates (PS&E) Requirements.” regarding special provisions. Otherwise, refer to Options 2, 3, 4 and 6 in Chapter 4: Design, Section 4. Even if the prime construction contractor will not carry out preventive measures, the PS&E may include general notes or notifications designed to avoid or minimize contractor downtime.
Construction-related responsibilities for managing anticipated hazardous materials may include:
  • Coordinating between the prime construction contractor, specialty contractor(s), consultant(s) and other subcontractors
  • Implementing provisions for the mitigation of hazardous materials or waste
  • Implementing oversight provisions for preventive action aspects of the contract
  • Documenting the actions taken for sub-items related to preventive action.
For unanticipated hazardous materials/waste encountered during construction, the major steps to follow after discovery are:
  1. Stop work in the affected location
  2. Identify the unanticipated issue (if this can be performed safely)
  3. Secure the site to protect workers and the public
  4. Notify the proper authorities and responsible parties
  5. Characterize the contaminant(s)
  6. Determine potential impacts to proposed construction improvements and to the environment
  7. Determine the worker safety and public exposure concerns
  8. Develop and implement hazardous materials/waste management measures
  9. Document the event starting with discovery.
FHWA may choose not to contribute funding toward additional costs related to hazardous materials if "due diligence" was not used in assessing the project limits during the planning stages of the project. If unanticipated contamination is encountered during construction, it may be necessary to defend any actions taken by TxDOT with thorough documentation to ensure continued FHWA participation.