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concrete exceeds a resistivity of29 KOhm-cm at 28 days, when tested in accordance with FM 5- 578. Submit three 4 x 8 inch cylindrical test specimens to the Engineer for resistivity testing before mix design approval. Take the resistivity test specimens from the concrete of the laboratory trial batch or from the field trial batch of at least 3 yd3. Verify the mix proportioning of the design mix and take representative samples of trial batch concrete for the required plastic and hardened property tests. Cure the field trial batch specimens similar to the standard laboratory curing methods. Submit the resistivity test specimens at least 7 days prior to the scheduled 28 day test. The average resistivity of the three cylinders, eight readings per cylinder, is an indicator of the permeability of the concrete mix. (e) When precast three-sided culverts, box culverts, endwalls, inlets, manholes or junction boxes require a Class III concrete, the minimum cementitious materials is 470 Ib/yd3. Do not apply the air content range and the maximum target slump shall be 6 inches, except as allowed in (b). SUBARTICLE 346-3.2.1 (Page 322) is deleted and the following substituted: 346-3.2.1 Slump Loss Test Requirements: Provide slump loss tests before drilled shaft concrete operations begin, demonstrating that the drilled shaft concrete maintains a slump of at least 5 inches throughout the concrete elapsed time. Inform the Engineer at least 48 hours before performing such tests. Perform slump loss testing of the drilled shaft mix using personnel meeting the requirements of Section 105. The Engineer may require a new slump loss test in the event that the temperature changes more than plus or minus 150F, the environmental conditions change or the volume increases. Perform the following procedures for slump loss tests: (I) Begin all elapsed times when water is initially introduced into the mixer. (2) The slump loss test is performed at a temperature consistent with the highest ambient and concrete temperatures expected during actual concrete placement. This test may be used for lower temperature placements without any admixture adjustments. (3) Ensure that the mix is at least 3 cubic yards and is mixed in a truck mixer. (4) After initial mixing, determine the slump, ambient and concrete temperatures and air content. Ensure that the concrete properties are within the required limits as specified in 346-3.1, Table 2. (5) Verify the water to cementitious materials ratio and other delivery ticket data meet design mix requirements. (6) Mix the concrete intermittently for 30 seconds every 5 minutes, at a speed greater than or equal to the midrange of the manufacturer's recommended mixing speed. When concrete is not being mixed, agitate the mixer at the midrange of the manufacturer's recommended agitating speed. (7) Determine slump, ambient and concrete temperatures at 30 minute intervals until the slump is 5 inches or less. Remix the mix for one minute at the mixing speed of the mixer before these tests are run. (8) Ensure that the concrete maintains a slump of at least 5 inches for the anticipated elapsed time.