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LF+�I��.� ��-C'7�1�)!�2 After leaks were found in the refrigeration at the John Rose Spced Skating Oval's refrigeration and ice system several years ago, on-going repairs have been required to keep the facility operational. The City suspects that a small leak in the polyethylene rink tubing allowed air to enter the refrigeration system. The air then reacted with the calcium chloride fornaiaag a corrosive chemical that corroded and degraded the steel walls of tl�e chiller tubes. An attempt to repair the system was made by plugging several of the chiller tubes that were deter�nit�ed to he leaking. Unfortunately tnore leaks were found. The City then hired a firm that specialized in testing pressure vessels of this type and found that more than 10% (typically regarded as extra capacity) of the tubes were degraded to a point that they were tanusable. It was unknown how additional tubes would fail in the near future. — The City hired Stevens Engineers to evaluate options available for renovating or replacing the chiller vessel including re-tubing the existing chiller vessel, replacing the existing chiller vessel with the same shell and tube type design and replacing the existing chiller vessel with two plate and frame type chillers. The City also wanted to consider improvements to the refrigeration system that will aid in future maintenance and monitoring of the system such as adding flanges on supply and return lines of the chiller vessel, corrosion coupon rack, pressure gauges, expansion tank relocation (i.e, elevate tank to bleed air from system) and other recommended improvements. In addition to the improvements to the 1al�a� Rose Oval's (herein referred to as the oval) refrigeration system, the City also requested Stevens Engineers to evaluate the existing ice system in the RSVC Arena and to evaluate the feasibility of connecting the oval's refrigeration system to the RSVC Arena to replace the aging refrigeration system in that facility. The repart format or outline follows Stevens Engineers proposal dated January 26,2005. COST ESTIMATES General An estimated project budget is included with each ofthe recommendations discussed in this report. The budgets were developed by estimating the probable construction costs based on similar types of wark and projects performed in 2004 and 2005. The estimated costs are based on 2005 prices and include all materials and labor for a complete installation. Note that there was a substantial increase in material costs, especially steel and concrete, in late 2004 and early 2005. Costs will vary depending on the time of year the projects are bid, the size of the projects, and the current economic climate. In addition to the probable construction costs of the proposed wark, other associated project costs are included to provide a total estimate cost far the project. The Estimate, Design and Construction Contingency line itenl in each cost table is included during ti�e preliminary phase of design projects because the exact scope of the project has not yet been determined. The contingency is hi�her far the Oval renovation project than ;f i4 RSVC project because of the increased difficulty of the project. This percentage is typically reduced to 5% during the final design phase. The Engineering, Legal and Administrative line item in e�cht cost table is provided to cover all work performed by the design team and all legal and administrative wark required by the Owner for projects ofthis type. �