For a large transportation project, 53 borings were made and only one boring showed some...

Withhold the information from the bid package because the full extent remains unknown. Ask bidders to provide a unit cost for remediation.

Provide a disclaimer on the contract documents about potential contaminants onsite and suggest the owner make the geotechnical report available to all bidders.

Insist the owner undertake additional investigation to determine the full extent prior to putting the project out for bid.

Proceed with design as is without any modifications since the results are statistically insignificant (i.e., well within expected deviations).