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Task 1. MCC -2, ATS, and VFD Replacement and Upgrades (.Yew Task) The existing MCC -2 and ATS at the South RO plant are in need of replacement since they are more than 25 years old, there are no available replacement components for this equipment, and corrosion of some of the bus bars may lead to its sudden failure. All of the high service pumps are fed off of this MCC, so it is a critical item that needs immediate attention. The feedwater pump VFD's (2) are also outdated and in need of replaceable parts which are currently obsolete and require special fabrication. The approach is to develop a phasing plan which allows for the demolition and replacement of the existing MCC to occur with minimal downtime to the existing switchgear. This plan will also include the transitioning of the existing high service pumps from the existing starters to the proposed variable frequency drives with limited loss of pumping capacity during this transition. Consultant will develop a plan, review with IRCU staff, and incorporate into a Since the plant was first commissioned in 1983 it has gone through several expansions and modifications including electrical room equipment. Currently, there is no current updated set of electrical single -line diagrams that describes the entire plant's power distribution system. Consultant will prepare a new updated single -line diagram to describe each of the four MCC's, the connected equipment to each, the existing switch gear, available spares in the MCC's and switch gear and rated current loads. Consultant will prepare construction documents that will consist of plans and specifications that will detail the replacement of existing MCC -2, ATS, and feedwater pump VFD's, including development of a sequence of construction that will maintain high service pump operations and minimize impacts to major treatment components. Some of the existing ancillary equipment can be phased without interruption or eliminated based on it no longer being in use. In order to provide improved reliability, some of the critical electrical loads should be shared between differenct MCC's. All of the existing high service pumps are powered off of the one MCC -2. Consultant will evaluate splitting some of the electrical loads to another MCC, such as MCC -1 or MCC -3. Consultant will design alternate means of powering the new high service pumps off of alternate MCC's. Consultant will conduct field investigations to review the accuracy of existing record drawings and to identify equipment ratings and associated connections for the design of MCC -2 replacement. Consultant will prepare up to 15 drawings of the MCC replacement and minor modifications to the existing electrical room to accommodate the new MCC. Consultant will prepare technical specifications for the MCC replacement and include these in with the bid documents. A 90% review set of drawings will be submitted to Owner for review and anticipate a one week turn around for review time. Consultant will provide IRC purchasing department 2 hard copies and electronic copies of the drawings and technical specifications. Task 2 — Modify Drawings and Specifications for RO Train Improvements (Amended) 5.'•.044\044572017 -SRO Upgrades%Scope\South RO Plant MCC Replacement - Amendment 2 rev 5.doc Page 2