SEWER PIPE TESTING AND SEALING A. Intent: The intent of this section is the elimination of infiltration into sewers that are otherwise structurally sound. Equipment: The basic equipment shall consist of a closed circuit television system, necessary chemical sealant containers, pumps, regulators, valves, hoses, etc., and joint sealing packers for the various sizes of sewer pipes. The packer shall be cylindrical and have a diameter less than the pipe size and have cables attached at each end to pull it through the line. The same equipment shall be used for both testing and sealing sewer joints. The packer device shall be constructed in a manner to allow a restricted amount of sewage to flow. Generally, the equipment shall be capable of performing the specified operations in lines where flows do not exceed the maximum line flows for joint sealing. Jetting or driving pipes from the surface that could damage or cause undermining of the pipe lines shall not be allowed. Uncovering the pipe by excavation shall not be allowed. Chemical Sealing Materials: The chemical grout shall be of a type which has a documented record of satisfactory performance in sewer usage. All grouting materials shall be delivered to the job site in the original, labeled, and unopened containers. Contractor shall submit with his bid, the brand name manufacturer of the chemical grout(s) he intends to use. The chemical grout(s) selected by the Contractor is subject to approval of the Engineer. Grouts shall be one of the following types: 1. 2. E. Acrylic base gel chemical sealing material - Avanti AV-100 or equal Urethane base gel chemical sealing material - Avanti AV-310 or equal B. C. D. Joint Testing and Sealing Procedure. 1. For the unit price bid for Testing Sanitary Sewer Joints, the Contractor shall furnish all materials, labor, and equipment to complete all work as specified. All joints in the lengths of sewer designated on the Plans shall be pressure tested with chemical grout or air to determine if sealing is necessary. If, in the opinion of the Contractor, Owner or Engineer, a joint appears to be defective to the point where sealing will be ineffective in reducing potential infiltration, testing of the joint will not be done. Cleaning shall be considered incidental and included in the unit price bid. The sewer lines shall be jet cleaned immediately prior to testing/sealing as required by the Contractor to remove solids and allow for proper seating of the sealing packer and operation of the television camera. Water required 2. for cleaning shall be provided by the Owner. 3. The packer shall be positioned over the joint by means of a measuring device and the closed-circuit television camera in the line. It is important that the procedure used by the Contractor for positioning the packer be accurate to avoid over pulling the packer and thus not effectively testing and sealing the intended joint. The packer ends (end elements, sleeves) shall be expanded using controlled air pressure. The expanded ends shall seal against the inside periphery of the pipe to form a void area at the joint, now completely isolated from the remainder of the pipe line. Into this isolated area, sealant materials shall be pumped through the hose system at controlled pressures which are in excess of groundwater pressures. The pressure device shall accurately show p.s.i. to the nearest one tenth (0.1) pound and shall instantly respond to and record any change in the void pressure. The joint shall be tested with a gauge pressure of one-half (2) p.s.i. per foot of depth of sewer as measured by the deeper of the two manholes between which the sewer section is located, or a minimum of four (4) p.s.i., whichever is larger. The pumping unit, metering equipment, and the packer device shall be designated so that proportions and quantities of materials can be regulated in accordance with the type and size of the leak being tested or sealed. 4. Air pressure will be applied until it is determined that the pressure cannot be built up in this void or until the test pressure is reached as recorded by the void pressure monitor. When either of these conditions is reached, the air supply shall be shut off. If no pressure can be built up, the joint will have failed the test. The joint will also have failed the test if the pressure drops more than one (1) p.s.i. in 15 seconds or two (2) p.s.i. in 30 seconds. Any joint failing the test shall be sealed and retested utilizing the same method and procedures until it does pass the test. The cost of retesting sewer joints shall be considered incidental and included in the cost of sealing sanitary sewer joints. For the unit price bid for Sealing Sanitary Sewer Joints, the Contractor shall furnish all materials, labor, and equipment to complete all work as specified. The diameter of the sewer lines to be sealed are as listed in the Proposal. The Contractor shall be paid for all joints successfully sealed and retested that initially failed the pressure testing. It is realized that this test and seal method may only be used on sewer pipe sections in sound physical condition. When bell cracks or chips are evident from pipe section offset, sealing may be undertaken where the offset is small enough to all proper seating of the sealing packer on both sides of the joint to be sealed. 5. 6. F. Joint Sealing Verification: Upon completing the sealing of each individual failed joint, the packer shall be deflated until the void pressure meter reads zero pressure, then reinflated and the joint retested. Should the void pressure meter not read zero, the Contractor shall clean his equipment of residual grout material or make the necessary equipment repairs/adjustments to produce accurate void pressure readings. Joints that fail to meet the specified test criteria shall be resealed and retested until the test criteria can be met in order to receive payment. Residual Sealing Material: Residual sealing materials that extend into the pipe, reduce the pipe diameter, or restrict the flow shall be removed from the joint and disposed of by the Contractor at an approved site. The sealed joints shall be left reasonably Aflush@ with the existing pipe surface. If excessive residual sealing materials accumulate in the line (and/or if directed by the Owner/Engineer), the manhole section shall be cleaned to remove the residual materials. Flow Control 1. To effectively conduct sealing operations, it may be necessary to provide for flow control or pumping of sewage flows. The Contractor shall be responsible for providing the means and equipment for such flow control or pumping. The Contractor shall be responsible for damages to property due to sewer backup while controlling sewage flow. All costs for flow control, temporary pumping, etc., shall be considered incidental and included in the unit prices bid for other items. When sewer line flows are above the minimum requirements (generally not more than 1/4 of the pipe diameter) or inspection of the complete periphery of the pipe is necessary to effectively conduct the sealing operations, one or more of the following methods of flow control shall be used at no extra cost to the Owner. a. Plugging or Blocking. A sewer line plug shall be inserted into the line at a manhole upstream from the section to be tested and/or sealed. The plug shall be so designed that all or any portion of the sewage flows can be released. Flows shall be restored to normal or not more than 1/3 of the pipe diameter during the joint testing and joint sealing operation. Pumping and Bypassing. Where pumping is required, in the opinion of the Engineer, to assure completion of the sealing work, the Contractor will be required to furnish pumping equipment, conduits, etc. Under no circumstances will bypassing of untreated wastewater to any storm drainage facility or surface water course be allowed. G. H. 2. b. I. Records: Complete records shall be kept of joint sealing performed in each section. The records shall identify the section in which the sealing was done, the location of each joint sealed, and the joint sealing verification results. Two neatly bound set of these records shall be delivered to the Owner at project completion. Guaranty: All sewer pipe joint sealing work performed shall be guaranteed against faulty workmanship and/or materials for a period of one year after the completion of the work. J.