5/07/2010

HOT Concerns with Centex plans for Hills of Rivermist retaining wall repairs

According to your 4/27 press release, Centex says that it has installed new inclinometers and that its engineering plans have undergone peer review, but we are concerned that people hired by Centex are beholden to them and expected to support them. We must question the neutrality of such a “peer” review since, to our knowledge, no one has yet addressed several of the issues we have raised, including:

·         Dr. Dave Petley’s 2/04/2010 analysis includes photos showing Toe Heave and Lateral Scarp that have yet to be explained by Centex or the City of San Antonio. Petley is a landslide expert and geography professor at Durham University in England. The “water balloon” theory mentioned below seems to explain Petley’s analysis.
·         A Western North Carolina Landslides blog complains about the Fraudulent Concealment of Hazardous-Soil Conditions in Texas and elsewhere outside of North Carolina, and how local governments are often complicit in that.
·         State representative David Leibowitz has continued to voice public concerns "with the construction practices at Rivermist going back to 2007." Even before the first collapse of the Rivermist retaining wall, Leibowitz asked the city about the quality of the fill material.
·         In Little Rivermists are everywhere in San Antonio, TREC inspector Mark Eberwine questioned the Centex wall design, saying, “If you stack tons and tons of unconsolidated earth on top of undisturbed soils, behind a 'retaining wall' and you fill the earth with millions of gallons of water (it's call rain), this water held by the dam is a 'lake'. What licensed engineer or homebuilder doesn't understand this?”
·         My own analysis of USDA Web Soil Survey data shows that the Hills of Rivermist subdivision was built on expansive soil that is known to be unsuitable for building (“very limited” in their words). That was “before” the retaining wall was built and tons of fill dirt added. Was the dirt that was added as fill on top of expansive soil also mostly expansive clay soil?
·         In The Hills of Rivermist Water Balloon Fight, I explained the characteristics of expansive clay soil and suggested that such soil could render the new Centex wall ineffective. Using the same “water balloon” theory, I am concerned that the newly installed inclinometers may give the City and Rivermist residents a false sense of security since very wet clay soil could easily “ooze” out around the pilings and underneath the wall itself.
·         In Texas Builder at center of San Antonio Crime Scene, I raised unanswered questions about why Centex was allowed to remove physical evidence (i.e. tons of fill dirt) from a potential crime scene, why City police and a private security firm prevented independent inspectors from accessing the site until after the fill dirt was hauled away, and why the Texas Attorney General never got involved in this case. We may now never know the answers or how expansive or contaminated that soil was.

1 comment:

  1. The City of San Antonio approved the wall in Rivermist.

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