Understanding Environmental Implications Of CIPP Rehab Technology

By Ed Kampbell, P.E. | April 2009 Vol. 64 No. 4
  • A project inspector, properly trained in CIPP, must be present for the duration of each installation;
  • The contractor must obtain and comply with all discharge related permits, including air, water, and wastewater treatment;
  • Styrene-resin based CIPP systems must have an impermeable inner and outer plastic film or plastic pre liner to promote complete polymerization, prevent resin migration and loss, and prevent styrene contamination of the interior of the finished product;
  • For styrene resin based systems, the contractor shall place an impermeable sheet immediately upstream and downstream of the host pipe to capture any raw resin spillage during installation and shall remove and properly dispose of any waste materials;
  • The contractor must submit preconstruction installation and cure specifications. Included shall be the requirement for monitoring temperature via a minimum of three thermocouples on the outer surface of the liner (upstream end, downstream end and at the approximate midpoint of the lining). The thermocouples shall be connected to a data logger capable of producing a print out which shall be given to the project inspector;
  • Additional lining materials and measures to ensure the containment of resin and styrene;
  • Procedures for monitoring the curing of the CIPP lining material;
  • Thorough rinsing of the finished CIPP;
  • The contractor shall capture and properly dispose of cure water, cure condensate and rinse water by transporting it to an off site disposal location; and
  • Water and soil testing to be done prior to and after installation. Samples shall be taken within three feet of both ends of the pipeline being rehabilitated. The post installation sampling must be accomplished within one week of the installation.

The impact of those changes to the VA DOT’s specifications have essentially been mixed. Some installers already had a policy in place to transport and dispose of the process water from hot water curing at a nearby wastewater treatment facility. This was due to the lack of definitive information on the process water’s potential environmental impact and the general public’s fear of chemicals that smell. Steam condensate is not typically transported away. Appropriate permits were obtained in the past by most installers.

Looking ahead