No one really knows exactly what conditions lie below the wavy floor of the old building at the site proposed for a new Piazza Library (shown above). Already, a costly “auger-cast column” system has been defined, which will require drilling down 20 to 30 feet in an eight foot grid across the breadth and width of a new building on this site and pouring piers to support the new floor, and this cost was not included in the original 9.3 million dollar estimate. In addition, there could be contamination which must be abated, or archeological features which need to be preserved– no one knows until we dig.
Some supporters of the Piazza library site, including the Renton Reporter, have repeated the idea that in terms of construction costs, remodeling the Cedar River Library carries “unknown” costs, while building at the Piazza site is highly predictable in cost. (You will find this assertion in this article for example.)
I don’t agree with this opinion however, as there can be many additional construction impacts hidden in the soil conditions, and these generally won’t be known until we start digging. These unknown underground conditions are an issue for the Piazza site, but not the Cedar River Site.
Some hidden conditions that have added to costs in Renton projects before are soils that are inadequate to support the building or the floors without reinforcement, contamination from previous uses, and the discovery of Native American artifacts on the site.
Already, a Geotechnical report provided to KCLS dated November 2nd 2011, done by Geo Engineers, has determined that the Piazza Library will need a more robust foundation system than the typical spread footings and slab-on-grade that were assumed when the 9.3 million dollar estimate was produced. The engineering firm has determined that the soil is so compressible and subject to liquefaction at the Piazza Library Site that the builders should install “lean auger-cast columns” (poured in-place concrete piers made with a lean concrete mix) up to thirty feet deep in a grid approximately every five to eight feet across the entire floor just to support the loads. The site is underlayed with multiple layers of silt and clay and alluvial sand, which makes it subject to liquefaction in an earthquake.
Of course contamination is always a concern when digging up old building sites, especially on locations where commercial use dates back before World War 2. While I am not aware of any surface evidence of fuel oil tanks, it is always possible that there are tanks buried in the site (either from heating oil or automobile fuel). It is also possible that before the sporting goods store moved in years ago, someone used the site in a way that allowed contamination to flow into the soils. Old fuel tanks and contaminated soil conditions are common discoveries in older parts of town, and they add cost to building projects. If these conditions exist, even deep under the surface, they will easily be discovered in the process of perforating the site with the newly required “lean auger-cast columns.” Here is a Seattle Times article which says that even the removal of a relatively small, basic home heating tank can cost up to $100,000 if there has been leakage. This cost would be many times greater for an underground gasoline tank. Click here to learn more about Renton sites where this work has been undertaken at great expense, such as the Texaco site that now hosts Big Foot Java, and the recently closed Jet City Espresso, which was formerly Charley’s Automotive.
Native American artifacts were discovered during the expansion of Renton High School in 2001, and during the building of the Henry Moses Aquatic Center in 2004. Both of these discoveries halted the projects and added costs, and could have led to costly redesigns if satisfactory resolution had not been reached with the tribes and the state regarding how to preserve the discoveries. Click here to read more (see page 25 of the report). The discovery report refers to the sites as “floodplain”, in reference to the Lake Washington and Black River conditions that existed before 20th century river and lake manipulation. No doubt the Piazza Library site is part of the floodplain, and was a historic area of activity for the Duwamish tribes.
While none of these risks should disqualify a site from construction, it is simply wrong to imply that there are no “unknowns” prior to excavating a site like the Piazza library location.
This photo, which is hosted by the UW Library, shows a 1930′s gas station at 3rd and Logan, in what appears to be the parking lot of the former Big 5 Sporting Goods store. The fuel tanks were single-walled back then, and they lacked monitoring for detecting leaks. There is no word yet on whether records exist which show the removal of these fuel tanks.
So KCLS has been sitting on the info about the more costly foundation needed for the Piazza site for half a year and yet, they chose only to reevaluate the costs for Cedar River site?
Yow… talk about not dealing squarely with Renton citizens.
Ben,
Not only has KCLS been sitting on this, so has our Mayor’s administration.
As far as “sitting on” information goes, KCLS has also withheld their proposed Schematic Design and corresponding new Cost Estimate for the Piazza site. The KCLS Board of Trustees were informed at their 5.23.2012 meeting that KCLS’s estimate for the Piazza site was on the order of $10.3 million. Apparently, this was not their first number either. KCLS Director Bill Ptacek, in responding to a Board Member’s question stated his design team, “have not been able to get the Schematic Design Estimate for (the Piazza site) down to the $9.3 million (budget) yet”.
Then, when asked if the $10.3 million estimate had been presented to the Renton City Council, Ptacek stated, “Renton does not want to hear anything until after the August 7 ballot”. Ptacek did not say who at “Renton”, but he had already announced in at least two meetings that he had “just come” from meetings with “the Mayor” and “the City Administrator”.
Thank you, Randy. The extent of soil and ground water contamination I am seeing in older areas eg downtown Renton, Burien, etc is significant and brings lengthy project delays and significant unexpected costs. The promotion of site conditions and costs at the Piazza location has not been realistic for anyone involved in financing revitalization projects.
The mayor and council members that have been pushing for abandonment of Cedar River Library have known for some time about the problematic costs of the foundation work for the downtown Piazza site. The geotech work, hazardous materials report (1 binder full!) and schematic design that I received by doing a public disclosure request were all readily available to them since they’re filed at City Hall.
The site is problematic not only from a cultural standpoint, since it’s entirely likely that native tribes could have had fishing camps in the area, but from a past use standpoint. For instance, the Nando Phillips and Son Union Gasoline station was located at South 3rd and Logan in Renton, ca. 1930. Yep, that’s right at the corner where the old Big 5 parking now is. The picture is in both the Renton Historical society files and the UW archives. Back then hazardous soil contamination was not even thought of. It’s entirely possible that contamination from that use, and other uses, is still on-site. It seems to me due diligence was not exercised when picking this site. Further, full disclosure of conditions at this site has not been made to the public.
Thanks Beth for the photo. It’s very interested additional information. I added it to the blog.
Beth, as an aside, Nando was the son in the picture. The Phillips of Phillips & Sons was Nando’s father.
Thank you for providing info on a gas station on this site. Shame on the city administration and KCLS for hiding this and the added potential risks and costs at the Piazza site.
I was at the museum a while back trying to get the hx of the Big 5 site but could not find anything other than what you have now revealed. Peripheral question–I thought we get our water from an aquifer–if so, how far down is it and how long before it gets contaminated by old fuel tanks and who knows what else?
Check the Aquifer Protection Zones map at the link below.
http://rentonwa.gov/uploadedFiles/Government/FIT/GIS/PDF_Files/Aquifer%20Protection.pdf
I believe the large shaded areas have some restrictions regarding the types of commercial activity that can be located in the protection zones.
The city does a good job of maintaining separation of potential threats from the active aquifers and on a few untapped aquifers. We have so much rain in this area that the City’s wells tap very shallow aquifers that are recharged quickly. If I remember correctly, Renton is not able to drill deep wells which might tap into the underground aquifer associated with the Cedar River which is protected in order to ensure lots of fresh water is unavailable for people so the fish have more than they really need. Shallow aquifers are the reason the city strongly encourages reduction of insecticides and pesticides by residents living in the aquifers areas.
The working wells are surrounded by test wells and a grid of test wells extend well outside of the aquifers. Areas of known contamination also have test wells located around them. Periodically a small amount of water is pumped from each test well which is tested for contaminant migration. Renton’s water supply is very safe.
All of the city’s working wells are east of old downtown Renton away from and upstream of the contaminated areas in old downtown and north toward The Landing. The worst spot is probably the Superfund site on the Paccar property north of N 4th just west of I-405/Sunset/Houser. Cleaning up that area would limit the spread of contamination and make about 30 acres of very well located land available for redevelopment.
Perhaps the easiest thing to do would be to cap the site with a Basketball / Hockey Arena surrounded with lots of impervious parking lots. If the city is looking for an actual revitalization project for downtown Renton, finding a way to encourage Paccar to do the right thing would do far more than jamming a tiny, incongruously modern library into the oldest part of Renton,
On the other hand, if I was a decision maker at Paccar, I would be far more worried about the economy getting Barack’d again this fall than what some anonymous person in an orange hardhat thought of my company.