Choosing a local material is a great way of supporting your local business and being environmentally sensitive. In the near future, I will be looking at different types of local materials and their various attributes in order to identify what products we have right here in Minnesota.
Last week the Mississippi Headwaters chapter of the USGBC hosted a bus tour of Cold Spring Granite company. The tour included visiting a granite mining operation, the fabrication plant, and also their new LEED-NC office facility. According to the tour, by taking the bus instead of driving all separately, we saved over 500 gallons of gasoline on our trip to Cold Spring, MN.
History
Cold Spring Granite company has been in business for over 110 years, and has been dedicated to new technology and innovate thinking since started by Scottish stonecutter Henry Alexander. This mission for innovation kept them in business through the Great Depression, war rationing, and other hard fiscal times. They have produced not only granite and natural products, but also ships and engines, in order to stay in business. Currently Cold Spring has 28 active mines in North America and imports natural stone from all over the world. The Cold Spring west facility (which we toured) has over 750 employees, of which 28% have been there for over 25 years. They produce many different products in many colors, from countertops and memorial stones to structural building components. Cold Spring Granite is committed to best mining practices and learning how to be a more sustainable company overall.
Attributes of natural stone products
Remember - all building materials have some sort of impact on the environment and use up something, and are only green in relation to other building materials. According to the tour, granite and natural stone have both green and non-green attributes.
Going Green
Part of Cold Spring’s commitment to sustainability is participating in the Natural Stone Council’s (NSC) green initiative. Like many building products industries, the natural stone industry is looking at how their products work as a green building material in the eyes of many green building standards, including LEED. In order to maintain integrity, the NSC wants to be very transparent and honest about the attributes surround natural stone materials, and hired a third-party research organization, the University of Tennessee Center for Clean Products, in 2007. Currently 70% of the domestic stone industry is contributing information for life cycle analysis data in hopes of understanding where natural stone products fit with life cycle analysis around the issues of embodied energy and water. After this research is completed, the NSC hopes to have a clearer path for how to move forward with greening their industry.
One potential path is to create certification standards for environmental stewardship in the natural stone industry. Federal and State Agencies currently guide practices, but the industry wants to go beyond to set other guidelines. In much the same way that FSC has done with sustainable forestry, environmental organizations and the natural stone industry could potentially work together to create the certification standards. Creating their own certification standard could reward companies for environmental stewardship and potentially make a standard for USGBC's LEED program to set preferences for. The natural stone industry already has the advantage of an existing product tracking system. This could minimize the challenges of chain-of-custody tracking that certified wood products currently have. When the results from the NSC research project are in, we can see how the natural stone industry decides to move forward with their environmental practices.
On the tour, we learned some areas of environmental stewardship that Cold Spring Granite is already attempting to address.
1. Water Consumption
Large quantities of water are consumed in natural stone extraction and fabrication. Water is used in mining to minimize dust, which can be a health hazard to workers. Steps are being taken to try to minimize the amount of water used, but it is an important part of the process. Recycling all of the water used in fabrication has become standard practice of Cold Spring Granite in an effort to be more environmentally-conscientious.
2. Site Practices and Reclamation
Large amounts of waste, site impacts, and the abandonment of mines post-use are big concerns. Extracting stone is still mining the earth, and that process remains the most efficient way to get to natural stone products. Thankfully extraction processes have greatly improved with new technology. Twenty years ago the blasting practices resulted in 50% waste, but today mines produce 20% waste in the mining process typically. Waste products can be recycled into a variety non-dimensional aggregate products, resulting in no waste products at all. Cold Spring produces no waste and also uses a new non-explosive process for some of the their mining. The process uses slot drilling, diamond wire for cutting rock and plastic bladders filled with water to push the stone out. This process results in even less waste around the edges of the block, eliminates blasting, and also requires less labor. Cold Spring does not abandon mining sites, and is looking to ways to help communities redevelop them into something else post-use. Currently about 2/3 of mining companies are concerned with mining abandonment.
3. Radon
All products from the earth potentially contain a certain amount of radon. The EPA has determined that most stone is not at dangerous levels, although some are higher than others. On the tour, the guide stated that there is no standard protocol or mechanism for testing a certain product specifically for radon, rather that it depends on the air in the space. She also said that she has never heard of a case of radon poisoning from natural stone, but that the NSC and Cold Spring Granite are taking radon very seriously and keeping abreast of progress for radon testing of specific products.
Cold Spring Granite and LEED
Cold Spring is dedicated to building all of its facilities to LEED specifications, and is looking at LEED for Existing Buildings to green some of its existing plants as well.The last part of the tour was their new LEED-NC office building. This building, waiting to attain LEED Silver certification, is attached to one of the fabrication plants. It takes advantage of natural daylighting, has outside views in 95% of its spaces, used low-VOC products, and is highly water-efficient. The project received Innovation and Design credits for using large quantities of extremely-locally sourced granite for most of the building; even some of the furniture is made of granite!
LEED-NC points related to natural stone and granite
MR 3.1 and 3.2 – Material Reuse/Salvage – Granite countertops and other stone treatments can be taken from existing buildings and reused in projects in either the same application or new ones
MR 5.1 and 5.2 – Locally sourced materials – Stone can be easily tracked from its source so it’s easy to decipher if it fits into the 500 mile radius
SS 7.1 – Heat Island Effect – using light colored stone in building façade or for paving applications reduces the amount of heat radiated from the sun and helps reduce the heat island effect.
Overall, the tour was great - really informative, fun, and well put-together. I am currently exploring the possibility of incorporating granite from Minnesota into one of our Minnesota-Made Homes. Stay tuned for more information on local materials!
For more information on Cold Spring Granite, click here.
For more pictures from the tour, click here.
