Retrospective Evaluation of Cured-in-Place Pipe - (NEPIS)(EPA ...
Retrospective Evaluation of Cured-in-Place Pipe - (NEPIS)(EPA ...
Retrospective Evaluation of Cured-in-Place Pipe - (NEPIS)(EPA ...
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experience and quality, and do not use a competitive tender for each project. While recogniz<strong>in</strong>g that they<br />
could save money, they consider the risk <strong>of</strong> problems due to <strong>in</strong>experience and <strong>in</strong>sufficient money to be<br />
too high. In 14 years <strong>of</strong> CIPP usage, only two projects were considered to have failed: a 200 m (656 ft)<br />
<strong>in</strong>stallation at a very difficult location could not be completed; and a 500 m (1,640 ft) <strong>in</strong>stallation was<br />
taken out because <strong>of</strong> poor <strong>in</strong>stallation and cur<strong>in</strong>g control. This represents approximately 2% <strong>of</strong> the total<br />
length <strong>in</strong>stalled to date.<br />
Leverkusen has concerns over the resistance <strong>of</strong> CIPP to water jett<strong>in</strong>g used for clean<strong>in</strong>g. Their clean<strong>in</strong>g<br />
uses water jett<strong>in</strong>g at 20 bar (290 psi) pressure, and they report some damage to l<strong>in</strong>ers from clean<strong>in</strong>g.<br />
Nevertheless they cont<strong>in</strong>ue to use CIPP. Their view is that quality <strong>of</strong> <strong>in</strong>stallation has improved<br />
significantly s<strong>in</strong>ce the 1990s, especially <strong>in</strong> areas such as reopen<strong>in</strong>g <strong>of</strong> laterals. Test<strong>in</strong>g has also improved<br />
so the overall standard has improved dramatically. They believe that the owner needs to take<br />
responsibility for QA/QC and for supervision and monitor<strong>in</strong>g dur<strong>in</strong>g <strong>in</strong>stallation. Even with experienced<br />
and trusted contractors the correct procedures are not always followed. For example, Leverkusen is<br />
consider<strong>in</strong>g <strong>in</strong>troduc<strong>in</strong>g <strong>in</strong>frared spectroscopy to its type test<strong>in</strong>g to ensure that the correct res<strong>in</strong>s are used.<br />
This suggests that the level <strong>of</strong> trust between owner and <strong>in</strong>staller rema<strong>in</strong>s low.<br />
In Australia, the situation is different because <strong>of</strong> the predom<strong>in</strong>ance <strong>of</strong> PE and PVC fold-and-form and<br />
spirally-wound l<strong>in</strong><strong>in</strong>gs. Sydney Water has used such plastic l<strong>in</strong>ers for rehabilitation for over 25 years. In<br />
its reticulation sewers, fold-and-form and spirally-wound l<strong>in</strong>ers account for the great majority <strong>of</strong> work<br />
undertaken. Use <strong>of</strong> CIPP has been limited ma<strong>in</strong>ly to patches, private sewers and laterals, and more<br />
recently, junctions.<br />
Queensland Urban Utilities <strong>in</strong> Brisbane also makes greater use <strong>of</strong> PVC and PE-based l<strong>in</strong><strong>in</strong>g systems than<br />
<strong>of</strong> CIPP. It shares the concerns <strong>of</strong> the other utilities over jett<strong>in</strong>g for clean<strong>in</strong>g <strong>in</strong> CIPP-l<strong>in</strong>ed pipes.<br />
Queensland Urban Utilities has addressed this through chang<strong>in</strong>g its operational procedures for jett<strong>in</strong>g by<br />
limit<strong>in</strong>g pressure and us<strong>in</strong>g specific designs <strong>of</strong> nozzle. They consider that CIPP is a valuable technology<br />
when the right product is used <strong>in</strong> the right conditions, but that it is important to understand its limitations<br />
and risks. The nature <strong>of</strong> sub-tropical regions is such that it may not be well suited to work <strong>in</strong> such<br />
locations. Also the experience, capability, and commitment <strong>of</strong> the <strong>in</strong>staller are considered paramount.<br />
The comb<strong>in</strong>ation <strong>of</strong> an <strong>in</strong>experienced client and an <strong>in</strong>experienced <strong>in</strong>staller will lead to problems.<br />
8.7 CIPP Use and Test<strong>in</strong>g <strong>in</strong> Japan<br />
Japan has a land area <strong>of</strong> 145,883 square miles, extend<strong>in</strong>g about 2,000 miles north to south on four ma<strong>in</strong><br />
islands; Honshu, Hokkaido, Shikoku, and Kyushu. Its population <strong>of</strong> 128 million is 79% urban, liv<strong>in</strong>g on<br />
just 3% <strong>of</strong> the land area. The capital and largest city is Tokyo with a population <strong>of</strong> about 8.5 million<br />
(25% <strong>of</strong> the nation lives <strong>in</strong> Greater Tokyo). There are 11 other cities with populations rang<strong>in</strong>g from 1 to<br />
3.6 million. Japan is subject to extensive tropical storms and some 1,500 earthquakes each year with a<br />
significant impact on pipel<strong>in</strong>e performance issues. Climate varies from temperate <strong>in</strong> the north to<br />
subtropical <strong>in</strong> the south with implications for H2S attack <strong>in</strong> concrete sewers.<br />
Through the last three decades, the government has pumped significant amount <strong>of</strong> money <strong>in</strong>to the<br />
economy by <strong>in</strong>vestment <strong>in</strong> public projects <strong>in</strong>clud<strong>in</strong>g provision <strong>of</strong> water and sewerage services, roads, rail,<br />
airports, and other urban <strong>in</strong>frastructure. However, <strong>in</strong> difficult economic times, the government has<br />
embarked on restructur<strong>in</strong>g programs and has begun to cut back on <strong>in</strong>vestment <strong>in</strong> <strong>in</strong>frastructure projects.<br />
In 2001, the government announced a cut <strong>in</strong> expenditure <strong>of</strong> $10.3 billion, target<strong>in</strong>g areas such as social<br />
security, public works, defense, and education. The impact fell heavily on the construction sector where a<br />
3 to 6% cut <strong>in</strong> public works has been experienced each year s<strong>in</strong>ce 2001.<br />
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