JOHNSON FRANK & ASSOCIATES 1 - 2003

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City of Santa Ana Update Of Sewer Facilities Master Plan Johnson-Frank & Associates Scope of Work and Technical Approach to Project Surveying Scope of Work: As requested additional sewer manholes shall be surveyed in the field with rim and flow line elevations collected. Survey elevations shall be measured to plus or minus 0.05 feet. The elevations used will be based on the Orange County Surveyor's published values. Currently there are 140 County Benchmarks within the City of Santa Ana. Each benchmark has NAVD 1929 as well as NAVD 1988 (1995 adjustment) elevations. On each manhole surveyed we will provide a template of the junction structure the vertical difference of the each of the inlets, outlet and center of manhole. The diameter of the pipe and pipe material will be noted when observable. In event that additional information is observable it will be noted. An example would be if there were apparent backfiow problems or broken structures. We will note the date and time that the observations were taken. The principle being that we may encounter a line at peak hours, which will be at maximum flow and the apparent surcharge, may only be related to the time of the observation. Upon completion of the field survey we will then provide a report to the engineer in charge. The report will include the benchmarks used, the NAVD 1988 elevation and the NAVD 1929 datum. The measurements collected from the field surveys will be shown on the sewer manhole templates and said templates delivered to the Project Engineer for his entry to the existing database. Technical Approach and Procedures: Naming and Numbering: The City of Santa Ana, Water Resources Division Project Engineer will designate the naming and/or numbering convention for each manhole surveyed. This will assist in our quality control and continuity within the project. We will work closely with the Project Engineer in determining our convention. Leveling We will use either the Wild digital level or one of our automatic conventional levels for all leveling on the project. The level circuit will be run and the results recorded and verified for compliance with project specifications. We will begin at the nearest County Benchmark or closest benchmarks established in the initial phase of the sewer manhole project and proceed towards the designated manhole. We believe that we can provide a rim elevation on many manholes between the designated manhole and the benchmark. This will not result in any measurable additional cost. This will result in a cost savings should the designated manhole be sealed or in an unsafe traffic situation. By establishing an elevation on several adjacent manholes we would not be required to set up levels through the preferred manhole. When we come to a problem manhole, we will request an alternate manhole from the Project Engineer. Each level run will be run between two benchmarks (County or Project) or based on a closed loop. Manhole inverts elevations and sketches: