Some turnkey proposals require the contractor to manage environmental concerns such as the containment and disposal of contaminated excavated foundation soils. Foundation contractors tend to no bid these projects or place an exorbitant increase to their proposal, losing the bid for the general contractor. Containment vessels are not that expensive and there are sites that can provide you with pricing for haulage to approved disposal areas. Rich lead-based paint on many older towers requires costly abatement procedures to remove it. Full canopies are sometimes required, adding weeks to the project. Check to see if the specifications require the supervision of an environmental hygienist. A Pennsylvania contractor found himself burdened with an additional $985.00 per day for three weeks because he omitted this expense in his proposal. The close to $15,000.00 expense was more than a drop in the paint bucket for the low bidder.