GBR discussion and need for guidelines revision Jun 2004

Shani Wallis, TunnelTalk

A day long symposium held in conjunction with the NAT (North America Tunnelling) conference in Atlanta in April 2004, was revealing more for how far apart Owners and Contractors remain, rather than how close in aim they have been drawn by introduction some eight years ago of the geotechnical baseline report (GBR) concept.

Having secured a press pass to attend the event, TunnelTalk listened as each of three representatives on either side of the tunnel construction divide raised a list of three concerns and had these responded to by an alter ego on the opposite side. On the podium, representatives included a consultant and a lawyer on each side, Randy Essex and Randy Hafer for the Owner and Peter Douglass and Bob Fitzgerald for the constructors, with Joe Gildner of Seattle Sound Transit representing Owners and Kirk Samuelson of Peter Kiewit & Sons putting the case for Contractors.

Perhaps the format, with moderator Bart Bartholomew, added to the sense of divide but the debate, with contributions and questions from the floor drew into sharp focus the points that require further consideration, definition and development.

Open ended issues raised included questions such as:

  • Should the GBR document alone, or in combination with the GDR (geotechnical data report), be included as contract documents?
  • Should the GBR, in addition to physical or material data, address ground behavior as it applies to the contractors "means and methods?
  • What happens when the GBR is "silent" on an encountered condition?
  • What constitutes a "good" GBR? The number of claims raised against it during construction?
  • Who is qualified to write the GBR?
  • How do DRBs work with a contract’s GBR in resolving disputes?
  • How does the GBR apply to design-build procurement?
  • Can or should below par or poor GBRs expose the Owner’s consultant to contractual liability?

Other points raised included:

  • A suggestion that the contractor’ s interpretation of the GBR in relation to preparing his bid should be included in escrow bid documents;
  • Warning of growing skepticism within the industry that DRB panels are not honoring the GBRs;
  • Acknowledgement that contractors will take, and must be allowed, the opportunity to interpret the GBR optimistically to arrive at what (in most cases) needs to be the lowest bid to win the job;
  • Confirmation that few contractors request clarification o fGBR data because, while the source of the query remains confidential, the re­sponse must, by bid statutes, be released to all prequalified or invited tenderers;
  • A notion that consultants are working to make GBRs DSC (differing site condition)-proof to avoid the potential for being sued for preparing a "bad" GBR; and
  • A point of clarification that suggested the interpretation should be not on exact numbers in the GBR but focus rather on meaningful differences, i.e. should the bidder anticipate 500 or 5,000gpm of water inflow or rather in terms of the consequences or impact of a DSC claim.

The question of exactly how many low bids have been rejected because of an overly optimistic interpretation of the GBR was not raised in the forum but the answer, discussed over the coffee break, was generally none although it was said that such a situation had occurred recently for a job in Atlanta. A final observation concluded that the market seems to go round in cycles or spirals without coming to maturity.

A show of hands at the end of the day confirmed that a revised edition of the Yellow Book guidelines for the preparation, interpretation and application of GBRs be prepared and that the revised edition include chapters on application of GBRs to design-build procurement projects and to the functions of DRBs. The revised edition of the Yellow Book – the Gold Book – was published in 2007.

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