Agmt13 JDH Corrosion Consultants, Inc.

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Other information that is critical to the overall analysis of the pipeline and the surface potential profile is as follows: • Locations of blow-offs and ARV's and the type of piping used for blow- offs and ARV's. Is the piping made out of copper piping or cast or ductile iron piping and is it coated or bare. Also if it is constructed out of copper piping is it electrically isolated from the transmission main through use of insulating bushings or is it electrically coupled to the water main. • Locations of in-line valves and whether they are coated or bare. • Locations of fire hydrants and the type of pipe connecting the water main to the fire hydrant. • Locations of any casings or manholes and how they are constructed. • Crossings with any gas pipelines or other foreign pipelines that may have cathodic protection systems. TASK 2 —SOIL CORROSIVITY PROFILE & CENTERLINE MARKING • Consultant shall review soil records from geotechnical reports available from the City of this pipeline alignment as well as from adjacent housing developments. Consultant shall also review soil type data from the US Geologic Survey. • Consultant shall measure in-situ soil resistivities at an interval of 250 feet (approx.) at depths of 2.5 ft., 5.0 ft., 7.5 ft. and 10 ft. and use Barnes Layer calculations to determine the resistivities at pipe depth along this pipeline alignment. • While conducting the soil corrosivity, profile consultant shall locate and mark the center line of the pipeline using a combination of inductive and conductive pipe locators in combination with visible pipeline appurtenances. White temporary paint will be utilized for centerline marking in asphalt locations and flags will be utilized in dirt or unimproved locations. • Consultant shall prepare a map of the pipeline alignment indicating the variations in soil corrosivity along the alignment. This data will be used in selecting the locations to perform the surface potential profiles. TASK 3 —SELECTION OF PIPE SEGMENTS FOR SURFACE POTENTIAL PROFILE • Consultant shall review alignment soil corrosivity profile and the other data collected during the documentation review phase of this project and select locations for conducting surface potential profiles. Surface potential profiles locations will be selected at areas analyzed to be of highest risk for each section of this water transmission pipeline. ATTY/AGR/2013.014/JDH CORROSION CONSULTANTS,INC. REV:01-25-13 VR Page 11 of 17