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Biosolids Frequently Asked Questions Virginia Department of Environmental Quality GET THE FACTS July 2015 Biosolids Frequently Asked Questions Where do biosolids come from? What are biosolids? ............................................... page 1 Biosolids are created through the treatment of sewage What is the difference between biosolids and sludge in a municipal wastewater treatment facility. sewage sludge? Wastewater treatment facilities receive sewage – the Where do biosolids come from? solids and liquids from toilets and drains. If the sewage How are biosolids used? comes from an industrial location, it must meet certain Are there different types of biosolids? standards before being sent down the drain. This is called How much biosolids is applied to land in Virginia? ....page 2 pre-treatment, where specialized processes are used to Who determines how and where biosolids are remove or reduce certain pollutants. In recent years, applied? these processes have dramatically reduced the amount of How do we know what’s in biosolids? heavy metals in sewage. Who can apply biosolids to land? ............................ page 3 Once the sewage reaches the municipal treatment facility, How much biosolids can be spread as fertilizer and it goes through physical, chemical and biological process- when? es to treat the liquids known as wastewater and remove What type of crops can be fertilized with biosolids? the solids known as sewage sludge. The sewage sludge Can biosolids be spread near my home? is broken down and sanitized to control disease-causing How do the biosolids rules protect human health organisms and reduce odor. Once the sewage sludge is and the environment? treated, it is called biosolids. When applied according to What has changed about biosolids regulations in DEQ regulations, biosolids are suitable for applying to Virginia? land as fertilizer to improve and maintain productive soils Who checks to see if the biosolids regulations are and stimulate plant growth. followed? ............................................................... page 4 Many processes and techniques exist to treat sewage What is a local monitor? and they vary by treatment facility. Contact your local Where can I find out more about biosolids in my wastewater treatment facility for details on treating area? sewage sludge and generating biosolids in your area. What are biosolids? How are biosolids used? Biosolids is a term that refers to solid, semisolid, or liquid When processed and applied according to DEQ and materials removed from municipal sewage and treated to federal regulations, biosolids are suitable for applying to be suitable for recycling as fertilizer. As fertilizer, land as fertilizer to improve and maintain productive soils biosolids are used to improve and maintain productive and stimulate plant growth. Biosolids may also be used to soils and stimulate plant growth. The use of biosolids is establish vegetation and reduce soil erosion on land subject to the Virginia Department of Environmental which has been mined, and improve drought resistance Quality regulatory requirements that exist to help keep because the additional organic matter increases the soil’s rivers, lakes, streams, bays and ground water clean; ability to absorb and hold moisture. Sewage sludge may protect plants; and prevent the transmission of diseases. be sent as waste to landfills or incinerators. What is the difference between biosolids Are there different types of biosolids? and sewage sludge? Biosolids that are used as fertilizer are divided into two When wastewater arrives at a treatment facility, the categories: Class A and Class B. Class A biosolids have solids are separated out and become sewage sludge. received a level of treatment that virtually eliminates Sewage sludge may be sent to a landfill, incinerated or disease-causing organisms or pathogens. If the levels of receive additional treatment to become biosolids. This heavy metals are low enough and the treatment additional treatment must occur for sewage sludge to be includes methods to reduce the possibility that animals called biosolids. will be attracted to the material, Class A biosolids 629 E. Main St., Richmond, VA 23218 804-698-4000 or toll-free in Virginia 800-592-5482 www.deq.virginia.gov may be distributed as Exceptional Quality biosolids. Because following 30 days, the public is encouraged to provide of the extra treatment, no special distance setbacks from comment on the proposed permit. Members of the public may wells or streams are required by the regulations to provide also request that DEQ host a public hearing. At the end of 30 environmental and health protection from pathogens. Excep- days, DEQ will consider all comments received and either tional Quality material may be bagged and is often sold approve or deny the permit. Before applying biosolids to alongside commercial fertilizers. Producers of Exceptional newly permitted lands, the permit holder must first notify the Quality biosolids are required to obtain permits from DEQ and local government and then wait 100 days. register with the Virginia Department of Agriculture and Consumer Services before selling the material. DEQ has biosolids specialists at its seven offices throughout the state who are dedicated to overseeing the proper Class B biosolids have less restrictive standards for content of management of biosolids. To read more about the regulations metals and disease-causing organisms, and thus require for applying biosolids on land, please visit more restrictive permit limitations so that specific land http://www.deq.virginia.gov/Programs/Water/LandApplicationB application practices are observed and environmental and eneficialReuse/Permits,Fees,Regulations.aspx health impacts are avoided. Class B biosolids standards are considered to protect human health and the environment as How do we know what’s in biosolids? well as Class A biosolids standards when coupled with DEQ regulations require sampling on a prescribed schedule to specific application restrictions, such as distance between ensure that the regulated parameters are measured and land with biosolids and any wells and streams, access treatment levels are achieved. The nutrient content of the restrictions for people and livestock, and certain crop material is measured so that the appropriate rate for the crop exclusions. to be grown can be determined. The frequency of testing depends upon the amount of biosolids a particular generator How much biosolids is applied to land produces; more production requires more frequent sampling. in Virginia? At a minimum, the following parameters are analyzed: From 2008 – 2013, an average of 220,000 dry tons of biosolids were applied annually to approximately 65,000 Nutrients Metals Other acres of permitted land application sites in Virginia. There are Total kjeldahl Arsenic Percent solids 7.89 million acres of cropland, pastureland, and woodland on nitrogen Cadmium Volatile solids Virginia farms, and biosolids was used on less than 1 percent Ammonia nitrogen Copper pH of this area. In comparison, commercial fertilizer was used on Nitrates Lead CaCO3 (for lime stabi- more than 1.9 million acres and animal manure on more than Total phosphorus Mercury lized biosolids) 363,000 acres (2012 U.S. Department of Agriculture Total potassium Molybdenum Alkalinity as CaCO3 Census). Nickel Additional parameters Selenium may be analyzed for Who determines how and where Zinc screening purposes biosolids are applied? when approving a new Wastewater treatment facilities that produce biosolids, and source. For example, any persons contracting with the facility to apply biosolids on analysis for PCBs land, must obtain a permit from DEQ before application. (poly-chlorinated biphe- DEQ’s permit regulations require that only biosolids that meet nyls) is required before a specific requirements are applied, and only on approved new biosolids source will be approved. lands with ongoing testing, notification and monitoring. To determine whether biosolids can be applied to a particular The U.S. Environmental Protection Agency has conducted site, an evaluation of the site is first performed by the land surveys of sewage sludge throughout the United States to applier. The evaluation examines water supplies, soil evaluate whether there are other constituents found in characteristics, slopes, vegetation, crop needs and the biosolids that would warrant further testing requirements distance to streams, lakes, rivers and groundwater. When before land application. Additional research is being con- DEQ receives a permit application with this initial information, ducted to determine not only the amount present, but also DEQ staff reviews the proposed biosolids sources and whether these amounts pose significant concerns. DEQ proposed land application sites to confirm if they are suitable. monitors the ongoing work of EPA in this respect, and if DEQ notifies the local government and residents adjacent to necessary, will respond to these findings with additions to the the land application sites. For the initial permit in a locality, list of regulated parameters. DEQ also holds a public meeting to discuss the proposed permit. After the public meeting, the staff will assemble a permit with consideration of comments from the public, local government and other state agencies. Once the draft permit is complete, a notice will appear in the local paper. During the 2 Who can apply biosolids to land? What type of crops can be fertilized Anyone who wants to apply biosolids
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