STATEMENT OF PROBLEM: Relocation of the Analytical Lab to WRRF involved CCC adding on to the plants existing Lab. The existing Lab had been in use for many years and it never occurred to us to check the negative air pressure in the Existing Lab. It appears after further investigation that the existing Lab had never had an negative air pressure prior to the start of this project.

COURSE OF ACTION: We asked in RFI 190 how the plant would like to handle this lack of pressure. We listed multiple options for GLWA to consider and they chose to have CCC fix the openings in the wall, floor, casework and ceiling''s in multiple rooms. Although this helped it did not fully solve the problem. The rooms are safe to work in but they do not meet the required numbers needed to achieve the negative air pressure desired.

It was in our contract to air balance at the end, but ultimately the negative air pressure achieved was not at the performance level the Owner wanted.

LESSON FOR FUTURE PROJECTS: If negative air pressure is desired in an existing area, have that area air balanced ahead of time to see what the current readings are before construction. Also, clarify with the mechanical sub-contractor prior to the start of the project that negative air pressure is or is not needed. This should be a question posed to mechanical sub-contractors in our post bid review when dealing with existing HVAC systems.