SUMMARY OF QUESTIONS AND RESPONSES (cont.)

ERDC TN-DOER-T4

December 2001

experience and training the operators had by the way they thought about their answer or solution.

Without experience and training the operators wouldn't have been able to answer the questions

satisfactorily.

Session Moderator: We find in our navigation projects, as well as the environmental cleanup

projects, that we require highly skilled operators. We also find that sometimes there is a difference

in production rates between daytime crews and nighttime crews. Staffing on different shifts and

their level of expertise reflect on the performance of the dredging operation. So, you can design all

of the elaborate plans, with all of the precision and accuracy; but, in most cases, it all comes down

to the dredge operator and his ability to control everything that is going on during his shift.

Finally, I asked this question about operator training because I think it is important that we

understand what we know and what we don't know about how we train dredge operators. One of

the most important things that I have learned over the last couple of days during the WEDA meeting

is that there are places to send operators for specialized training not only here in the U.S. but also

overseas. Places like Texas A&M have dredging simulators. So, I think we need to examine further

our dredging contract specifications to properly specify the technical qualifications and skills needed

for personnel who do environmental dredging jobs.

Session Moderator: What are the appropriate economic measures of environmental dredging?

Panel Response: The response by a panel member was that this was a tough question and there

was not a silver bullet answer. He offered that the owner and engineer try to go through a number

of iterations to determine what makes sense early in the project. Many times the client is looking at

cost of a CDF on his own property; if he were to build this site it needs to accommodate a certain

percentage or a certain absolute value of overdredging material. He needs to determine what it is

worth to him to minimize the size and the cost of that CDF and to compare that against the costs of

delivering the 2- to 3-in. [50- to 76-mm] type of dredging precision.

It was also pointed out that the technologies presented by the contractors, Sevenson and Bean, may

not always be economically feasible. Dredging costs vary around the nation from a low of 50-75

per cubic yard to as much as $85 per cubic yard. The goal is purely to provide the best value to

the owner. The economics have to make sense to the owner. What may make sense to dredging

operators may not make any sense in the end to the owner. The result of the discussion was that

iteration should be part of the process of getting the best value for the job.

Session Moderator: I think there is a subpart to this question. That is, I would ask the panel to

comment on incentives versus benefits in terms of defining economic measures of an environmental

dredging project.

Panel Response: Recently, a client had a situation where he had approximately 33,000 to

35,000 cu yd [25,000 to 27,000 cu m] of contaminated sediment in the area that he was trying to

clean up. He built a CDF on his site to contain this material at an estimated cost of around $150 per

cubic yard. The client specified a clause in the dredging contract that said, "I want this quantity

removed to a certain line (elevation) and if you remove any material below this line, you pay me

$150 per cubic yard." In effect, he was liquidating his damages back to the contractor that if he