It had taken well over a year to bring to fruition an opportunity for Landfill Service Corporation to demonstrate their Posi-Shell Cover System for a large environmental firm operating one of the solid waste landfills in the Hong Kong Special Administrative Region of the People’s Republic of China. Due to encroaching populations, the engineers and managers of this well run facility conducted extensive international investigations for products to enhance the existing gas odor control measures already in place. They had become convinced that Posi-Shell, with it’s long history in this arena, would work for their situation as well. Additionally, they recognized Posi-Shell’s other numerous uses as well such as Alternate Daily Cover, Erosion Control, and Hydroseeding.
However, the Asian climates and weather conditions posed a serious challenge for a product, such as Posi-Shell, that is spray-applied and requires curing time. RAIN, lots of it, lots of the time!
After several months of working out the logistics involved with an overseas demonstration of this magnitude, LSC representatives departed in mid-September armed with their standard tool, Posi-Shell Advanced Formulation, but for this trip they would also be utilizing a newly developed additive called Xtreme Rain Shield, which had been developed for situations just like this. Xtreme Rain Shield is a cellulosic polymer additive, in layman’s terms, the product gives Posi-Shell an increased resistance to heavy rains…even before it has cured.
Having performed well during several field evaluations and a few commercial installations, the LSC team was confident in Xtreme Rain Shield’s ability to live up to it’s name, but had really only tested it up to a two inch rain, in a ten minute time span immediately after application. By demonstrating in September in Hong Kong, it appeared that simulated rainfall may be required (spraying water out of a hydroseeding unit), since the summer typhoon season was “technically” over in that region. The team welcomed this notion as controlled testing is better than testing left to the elements.
As things go, however, a latent typhoon had been lurking out on the Sea of China and decided to make landfall at the landfill the very first day of the demonstration! The first demo load was applied to this slope early afternoon Monday (photo 1), while the rain was beginning to come down in earnest (photo 2). Shortly thereafter everybody was sent to their homes or hotels as the storm intensified and continued through noon the next day. Overnight, it reached signal 8, which can have sustained winds up to 116 mph. Fortunately no major damage was inflicted in Kowloon or at the landfill, other than a few downed trees and several thousand square feet of a protective rain cover which was torn away by the wind.
Tuesday afternoon, when the team returned to the site, there was a short moment of suspense while heading to their demonstration panel, as they had just been told by the landfill engineer that over four inches of rain had fallen during the storm. To their relief though, he followed up by saying “…but the Posi-Shell looks pretty good”. Photo 3 shows the product after the storm. The dark streaks are areas where slight washing occurred, although not completely through to the soil beneath the cover. The landfill staff concluded that the washing probably only amounted to about five percent. A huge success given the fact that there was zero cure time before the rains started pounding it!
