C04e Attachment 5 Addendum Blanchard Sewer Line Replacemt 127EAX26Q0052.pdf

This document is an addendum to the Project Manual for the Blanchard Springs Sewer Line Replacement project, issued on 4/28/2026. The addendum modifies Division 33 (Utilities), Section 33 05 61 (Precast Concrete Manholes), Part 2 Products, specifically addressing interior lining and exterior coating requirements.

The specification requires that precast manhole joints be sealed with butyl rubber mastic conforming to ASTM C990, with 6-inch butyl mastic tape applied to exterior joints and non-shrink grout applied to interior joints. Interior and exterior surfaces must be completely coated with an approved epoxy liner system consisting of 100% solids, solvent-free two-component epoxy resin with select fillers designed to minimize permeability and provide sag resistance. The epoxy liner must meet minimum performance standards including Shore D hardness of 88 (ASTM D-2240), tensile strength greater than 7,000 psi (ASTM D-638), and flexural strength greater than 10,000 psi (ASTM D-790). The specification designates Raven 405, manufactured by Raven Lining Systems, as the required product or an approved equal alternative.