On November 25, 2014 the City Commission authorized award of a contract to Youngquist Brothers, Inc. (YBI) for installing two Industrial Deep Injection Wells and a dual zone monitoring well at the Springtree Wastewater Treatment Plant.  These wells will discharge waste streams from the water and wastewater treatment plants to a depth of about 3,000 feet below the land surface.  Each of these wells include multiple telescoping steel casings, cemented against the next and the outer-most casing is cemented against the surrounding geological strata (please see well construction profile attached).  A reinforced fiberglass injection tubing string runs within the inner-most steel casing and is sealed at the bottom with a mechanical packer seal.  The space between the inner tubing and inner-most casing is liquid filled, pressurized and monitored for mechanical integrity as designed for regulatory compliance.

YBI successfully installed the first deep injection well (DIW 1) and the dual zone monitoring without any complications.  While installing DIW 2, the contractor encountered interference with insertion of the injection tubing at a depth of about 1,400 feet,  and informed the City and our consultant that a bulb or a blister-type of obstruction was encountered on the inner wall of the casing, preventing installation of the tubing and packer below this depth.  The contractor proposed modifying (milling) the threaded couplings in order to pass the obstruction at this depth.  This recommendation preserves the liquid filled annular space.   

For additional assurance the City negotiated and gained acceptance from YBI to extend the warranty for DIW 2 for a ten year period from the contract substantial completion date, and extend and restructure the public construction bond securing completion of repair or replacement work as may be necessary at anytime to restore mechanical integrity from the date of substantial completion of the DIW 2.  The consultant and Utilities Department additionally negotiated with YBI to return within ninety days prior to year 5 and year 10 following substantial completion to perform required mechanical integrity tests on DIW 2 at YBI's cost (required by the Florida Department of Environmental Protection operating permit). The project completion date is scheduled for December 16, 2016.  

The City's design consultant has reviewed this proposal and determined YBI's proposed modifications are reasonable and satisfy the required design criteria.  The engineer's recommendation is subject to the City obtaining an additional 10-year warranty as agreed by YBI.  Authorization is requested for this First Amendment to the contract and to accept the Bond General Purpose Rider and Ten Year extended Warranty as additional assurance the City will receive reliable service from this well.  The typical warranty included within the City's construction contracts is one year.