May 27, 2011 Editorials
Everyone wants to believe that their construction project is going to run smoothly and that the engineer has thought of everything, but no matter how well the design is put together we usually can find at least one thing that would have ended up biting the owner in the end. This happened recently during the construction docuement review on one of our geothermal projects. We had noticed that the desing team had specified the use of methanol as their anti-freeze of choice for the water in the geothermal piping. Although not as frequently used as some other burst protection options, it is a valid alternative. After confirming with the owner that their staff was appropriately trained in the use and clean-up of this toxic chemical, we turned our attention back to the system itself. Other than the volatility of methanol, it is also corrosive but unlike the oxygen in the water, which can be removed with chemicals, the methanol will continue to eat away at cast iron and steel sytem components over their entire service life. Fortunately for the owner we discovered the misapplication of these and other metals prior to the docuements going out to bid. So was the designer to blame? I’ll let you be the judge. In his defense, he did have a general note on the drawing stating what materials should be used. But in looking at the specifications of the equipment we found that there was either a lack of specific information or the wrong material was specified. Ultimately, this then relies on the contractor to know what they need to purchase premium component materials that resist the corrosion of methanol, but as contractors are constantly looking at their bottom line, it tends to be installed as incorrectly specified or turns into a large change order. Thankfully with that issue resolved, the owner can rest easy knowing they have traded a small premium updgrade now, for a long-term expense down the rode.