Frequently Asked Questions About The Aggregate Industry
Due to its close proximity to the earth’s surface, sand and gravel (aggregates) extracted normally have a natural moisture content between 2% and 4% which, according to United States Environmental Protection Agency (USEPA) research data, provides adequate pollution control to convey raw materials on site. Emissions from gravel processing operations are easily controlled and the emissions typically do not travel beyond the plant area. In addition, most of the aggregates mined are washed at the plant and therefore, produce minimal emissions at the plant because the products become saturated during processing.
Fugitive emissions may be generated by vehicles entering and exiting the plant site and are visible to passing motorists. Mine operators use “best management practices” to reduce the level of fugitive emissions that leave the site. Paved entrances, on-site water trucks, street sweepers, wheel wash systems, vegetation, etc. are employed to reduce or eliminate fugitive emissions that can be tracked off site.
Sand and gravel mining is regulated by the Illinois Environmental Protection Agency (IEPA). The IEPA, Bureau of Air is in charge of enforcing Federal and State air pollution regulations. Mine operators are required to obtain an Operating Permit from the Bureau of Air for the regulation of Particulate Matter (PM) emissions in order to convey and process aggregates.
Mine operators are also required to complete an Annual Emission Report to disclose PM emissions for each calendar year, based on recorded production levels and emission rate factors generated by USEPA research data. In addition, when new equipment is introduced into the production process, operators are required to notify the IEPA, test the equipment and submit the test results within a specified period of time.
Small mines are usually only allowed a total of about 25 tons of pollution to escape into the air each year the actual calculations usually show far less than the allowable. However the large coal fired power plants are allowed several million tons each year. At roughly one millionth of the pollution of a power plant, we just don’t amount to much as an industry as far as air pollution goes. Cars and trucks are far more dangerous to the environment. While good road surfaces actually increase fuel economy and cut air pollution emissions from those vehicles. Good Roads come from mining!
In most of our aggregate mining operations we do not discharge water because we recycle water during mining and processing operations. Typically, water from on-site surface water sources (including the capture of storm runoff) is used to wash the silts and clays out of the sand and gravel, so the finished products are clean for market applications. The wash waters containing silts and clays are pumped into a sedimentation pond, allowing the fines particles to settle out on-site. “Clean” wash water is then recycled back to the processing plant for continued use in the washing process. In addition, some of the water retained by on-site surface water sources is lost to evaporation or infiltrates into subsurface flows.
The IEPA, Bureau of Water is in charge of enforcing Federal and State water pollution regulations. Mine operators are required to obtain an Operating Permit from the Bureau of Water for the regulation of storm and process waters within a mining site. Depending on the type of the mine configuration, the State will require a permit to retain or a permit to discharge all waters associated with the mining activities.
If a discharge permit is required, the mine operator must submit monthly monitoring reports to the IEPA, with calculations indicating the quantity and quality of water being discharged. The water that is discharged from a site is usually a mixture of storm water, groundwater seepage, and surplus wash water, and must meet the effluent limitations of the Permit. Along with this important permitting function, the Bureau of Water is empowered to perform unannounced, random inspections. Operators who violate Federal and State water quality laws are subject to fines and criminal prosecution.
Since 1991, The County of McHenry Illinois Planning and Development Department has compiled a large database of information generated by a mandatory groundwater monitoring program at all aggregate mines regulated by the County. This data, public information available from the Department, clearly establishes the following: aggregate mining does not have an adverse impact on McHenry County groundwater resources.
Noise pollution is regulated by the IEPA and noise levels are required to be in compliance with State law. In addition, mining operations are typically screened from the public view by earth berms, trees, etc. that provide more than adequate noise attenuation at the property boundaries.
The IEPA does not require aggregate mining operations to obtain a noise pollution permit. Noise pollution concerns are seldom generated beyond the boundaries of the plant site. If this were a problem, the industry would see increased regulation from the Agency.
Perception vs. RealityNoise as perceived by our brain is an amazing thing! Standing on your patio using a sound meter, a cricket just 10′ away is louder than a rock crusher 600′ away! This is because sound levels diminish as you increase distance from the source! But our brains still notice the rock crusher..Why?…. Well, it’s because our brains acknowledge the cricket as a “natural sound” that is supposed to be there and the rock crusher is a “rhythmic mechanical” sound which is different than natural. So our perception is that the rock crusher is louder when in fact it’s not at the distances above. This ability to exaggerate our perception of things was probably developed as a defense mechanism or a tool for our hunting instincts. Just like predators or prey in the animal world use sounds to detect each other.
No, vibrations primarily from blasting operations are regulated and because the operation taking place is at least several hundred feet away, the vibrations are minimized at these distances to be almost imperceptible and certainly below the level that would cause any damage to a well or structure.
Surprisingly, not all mines use explosives and those that do, have all the more regulations to contend with. Most gravel operations don’t need any form of blasting because the extraction process is easy enough that it simply is not necessary. Quarries often need to blast to free the rock from its original position and break it into pieces small enough to be handled. The IDNR monitors this blasting activity very closely. After each blast the IDNR requires the company to provide a great deal of scientific information related to the vibration in the ground and the sound or air blast generated. Seismographs like those used in monitoring earthquakes are used both and near the blast site and far away by the nearest habitable structure. These are then compared by the IDNR to values allowed by the blasting permit for compliance checking.
Perception vs. Reality – Having attended a few blasts at fairly close range I can tell you the noticeable thing is the vibration under your feet and low rumble of sound! This too is a matter of perception vs. reality. Again our brains are amazing and can sense the very smallest changes in acceleration, then they exaggerate the result to make us perceive a larger movement. This is a defense mechanism to allow us time to react. This is like when you are stuck in traffic on a long bridge and you feel the up and down movement of the bridge deck as a big truck drives by. It feels like you are moving several inches but the reality is that you are “bouncing” a very small distance, say a few millimeters.
Most aggregate products are moved by trucks. The market of your area requires a fairly fixed quantity of this product to enter your community as it has for many years in the past and will continue to in the future. A pit or quarry nearby just means that the amount of trucks in your area will spend less time on the road and create less traffic in general. But remember that quantity of materials is still required to be delivered to construction projects in your area whether it is a new shopping mall, repairing the street or delivering your neighbors new driveway materials.
Most residential areas don’t see much truck traffic for two reasons. One reason is that the roads use may be restricted or they may not be designed to support them. The more likely reason is that trucks need to get out to the highway to make better time. In either case aggregate operations are often required to maintain the road or pay fees to the governmental body that does. Local zoning restrictions often require the trucks to use only approved routes for delivery and they consider traffic implications when making these restrictions.
During our involvement in the McHenry County Gravel Advisory Council, the council was asked to collect and investigate all truck related complaints collected by local government agencies and the Sheriff’s department. What was discovered was that of the few complaints collected regarding trucks each year most were involving “closed box” cargo trucks hauling goods to the local supermarket or farm related products, but not aggregate trucks at all! The council made of half governmental people and half gravel producers learned, once again, that the perception of trucks being an issue in the area was simply false!
The Illinois Department of Natural Resources (IDNR) requires a Surface Mining Permit for all operations that affect over 10 acres per year by mining or remove more than 10 feet of overburden. A Surface Mining Permit application requires the operator to submit an operating plan that illustrates how the land will be affected by mining operations as well as a reclamation plan that describes how the mined land will be restored for future use.
In order to receive a Surface Mining Permit, the operator must post a bond with the State of Illinois that obligates the company to perform the activities specified in the reclamation plan. Mine inspections are performed annually by IDNR representatives; progress is mapped via aerial photography.
Reclamation bonds can only be released if the IDNR inspector finds that enough work has been completed to allow the property to be returned to a productive use, as set forth in the operator’s reclamation plan. If the operator fails to comply with the approved reclamation plan, the State may file a claim against the amount of the bond. The State then uses the bond proceeds to complete the reclamation of the mined land.
The State’s aggregate mine regulatory program was enacted more than 30 years ago. To date, only one aggregate mine in Illinois has failed to comply with its reclamation plan, thereby triggering bond forfeiture. The reason for this excellent industry track record is apparent – the residual value of reclaimed land is simply too valuable for a mine operator to walk away from.
As noted in Question #4, mining companies understand the value of land. Reclaiming land after 20 years of mining can produce substantial benefits beyond the mining activity itself. Some of the most unique developments across the U.S. can be attributed to creative, long-term mine planning for secondary uses.
Independent evaluations have been performed and show that lands adjacent to or near an aggregate mining site are not affected by mining activities. Mining is an interim use of the land – with proper execution, there is a future land development that will follow that interim use. While there is some sensitivity involved in buying and selling real estate property adjacent to a mining operation, it is apparent that real estate values are generally not impacted by aggregate mining.
Commercial aggregate mining has taken place in close proximity to neighborhoods for many decades. In the past 20 years, the rural nature land surrounding typical mine sites has changed significantly due to economic growth. Many mining companies in the Country are now surrounded by this growth, and are changing with the new urban landscape.
Most aggregate producers are heavily involved in the day-to-day lives of their neighbors and work hard to be good corporate citizens. For example:
• They participate in a variety of educational activities including: field trips, tours and open house events
• They support local commerce initiatives and generate tax revenues
• They provide materials for special projects (schools, park districts, etc.)
• They participate in neighborhood committees adjacent to their operations
• They support many jobs at the local level, including the trucking industry
• They supply the region with high quality materials at competitive prices