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Exhibit # 1 To Amendment #3 Work Order Number 14 South RO Plant A/C System Design PROJECT DESCRIPTION Due to the recent failure of MCG2 bus bars and apparent corrosion of equipment in the electrical room, it appears that outside air laden with hydrogen sulfide (HZS ) is entering the electrical room and causing accelerated corrosion of the copper and aluminum components . There also appears to be inadequate capacity of the A/C cooling system . In order to further prevent process room air laden with hydrogen sulfide from entering the electrical room, fresh outside air should be designed into the A/C system to provide positive pressure in the electrical room. This may require a larger unit since it would be cooling and drying outside air high in humidity . It may be prudent to provide a separate smaller A/C system for the offices in lieu of increasing the electrical room a/c system. This will also help create a more positively pressurized electrical room than the office and control room. The following scope consists of designing a split air conditioning system which will provide positively pressurized electrical room and separate cooling of the control room and office spaces . The existing single rooftop unit with thermostat in the control room appears to be inadequate and is nearly impossible to reasonably satisfy cooling conditions in all of the rooms due to the large differences in thermal characteristics . It is assumed that a split system should be designed . The following scope of services is provided . Task 1 . Design The partial ground floor of approximately 4 , 000 sqft at the east end of the building houses an electrical room, control room, lab , lunch room, offices , and bathrooms . It is proposed to design two split systems for the electrical room and one split system for the office space . Although the existing A/C system is a 10 ton system, we will evaluate this size and ability to provide adequate cooling capacity . A drawing will be prepared which will identify areas in the electrical room needed to be sealed such as conduits , wall penetrations, and duct seals . KHA will engage a subconsultant to prepare design drawings , consisting of a floor plan , equipment schedule , electrical schematic for power to each of the units , details , sections , and general notes . It is assumed that approximately six (6) drawings will be prepared . KHA will submit 90% review drawings to Owner for review and incorporate one set of review comments . Two sets of signed and sealed drawings will be provided . Energy calculations will be prepared for the offices , but not for the electrical room since the current code does not require these where operators do not work on a regular basis . KHA will perform a site visit to collect information and data on the existing system. K:\WPB—Civjl\044572017 - SRO Water Plant Improvements\Scope, JS\South RO Plant HVAC Design rev2 .docx Page 1