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HomeMy WebLinkAboutShrimp Farming - Potential Growers-Potential Growers Consider Idea of Shrimp Farming I Marvesta ... Page 1 of 3 i`�1 t n??013 'j c News POTENTIAL GROWERS CONSIDER IDEA OF SHRIMP FARMIN tj CAMBRIDGE, Md. — Packed into a conference room at the Cambridge Airport on a Saturday, nearly 40 people gathered on March 23 to learn more about Marvesta Shrimp Farms and to consider the possibilit�F- of becoming shrimp farmers themselves. "If the moneys there, it's something different to get into," said josh Harding, a farmer from Rhodesdale, Md., who is considering aquaculture to diversify his operation and came to the meeting for more information. Guy Furman, owner of Marvesta, talked to prospective growers about how committed he is to providing fresh, environmentally friendly and healthy shrimp on a consistent basis. He said his company does not use artificial hormones, antibiotics, or chemicals. "We are competing against frozen imports;' Furman said "But we're selling to a premium market and we shoot for something reliable and consistent." Potential,,,,, growers learned that Marvesta has been able to use a zero -exchange indoor system, which is the "cheapest and best water reuse system on the market;' Furman said The water in the system is recycled and only needs additional water to replace evaporation losses. While chicken growers, current and past, with existing poultry house were targeted as potential shrimp growers, there were several others who were outside of the poultry industry who attended. The initial investment to become a Marvesta grower is $50,000. It includes one year of consulting, 12 tanks and equipment, and the first six months of feed, shrimp and supplies. Grants are available to help with startup costs, Furman said. A 24 -tank system is $80,000, and additional 12 tanks are available for $25,000, but will not include consulting and supplies. Furman said he is confident about the commercial grow out process because he has seen excellent results from another shrimp company in Indiana, RDM Aquaculture, LLC and its owner,, Darryl and Karlanea Brown will act as consultants for Marvesta growers. "We are with you all the way;'sai Karlanea Brown. "You fail, we fail. That's not an option." Brown will train growers on how to maintain proper water quality and how to grow the bacteria needed for shrimp to flourish. The couple, who transitioned from hogs to shrimp, have helped others do the same. They live 600 miles from the nearest saltwater and have six nursery tanks and 14 grow out tanks. They also have greenhouses and 500 acres in corn and soybeans. Using the zero exchange aerobic heterotrophic system, "our water is three years old;' she said. According to Furman, the typical survival rate for shrimp is 80 percent but the Browns' have well over a 90 percent survival rate. The Browns raise their shrimp in 12 -foot round tanks "similar to a swimming pool;' said Brown. Shrimp do jump when stressed so they need a cover and require the equivalent of sun and moonlight, said Brown, adding that they livein 85- http://marvesta.com/potential-growers-consider-idea-of-shrimp-fa... 1/6/2015 ?otential Growers Consider Idea of Shrimp Farming I Marvesta ... Page 2 of 3 degree water. "You need to dedicate about two and a half hours to them a day," Brown said. "Everything you're getting here is something we've been working on," said Furman. Growers will have to test the water daily and corrective measures can be taken by altering the feed. "If you, don't water test you could lose a tank in four days,' said Brown. Growers will have the shrimp for four months, stocking three tanks at a time. Like poultry, the system will be set up with a pressure monitoring alarm in case of fluctuations in the tanks. Attendees asked specific questions about site requirements, permitting, and sustainability. Some wondered if the heat from the water would take a toll on the buildings. "We ventilate our buildings year round," said Brown. "We control condensation with a small vent fan." Participants were also concerned about the cost of feed and testing supplies. Furman said he buys the feed in bulk and that "our goal is to make money buying the shrimp not on the other stuff." With such interest, a few attendees worried that the shrimp market would become saturated. Furman said he does not think there will be a flood of product to the market. Furman told the crowd that in the United States, shrimp is the second largest natural resource imported after oil. "Marvesta is a brand that has never had a problem," he said. "It's a premium product. Long term, we'll make you aware of what products will be cheaper — feed, equipment — we'll stick with you." Calvin Musser, of Laurel, Del., who had tried aquaculture with another company but was not satisfied, said, "I'm very interested, I'm ready to do it again." Furman said the return -on -investment is about three and a half years. Furman has visited a several potential farms and some of the growers have expressed interest in doubling the number of tanks. By Michel Eleben Staff Reporter - American Farm.com, Link to Original Story , 1148 9 0 6 LEAVE A REPLY���' Your email address will not be published. Required fields are marked Name Email Website Comment ' 71 H k ty W71y ¢A } d, ..m Dr"4 ,. You may use these HTML tags and attributes <a href="" title=-'> <abbr title=-'> <acronym title=-'> <b> <blockquote cite='-> <cite> <code> <del datetime=­'> <em> <i> <q cite='-> <strike> <strong> r, rq NAVIAl IC)N ABOUT US WHY MARVESTA? WHY INDOOR SHRIMP FARMING? n FREQUENTLY ASKED QUESTIONS http://marvesta.com/potential-growers-consider-idea-of-shrimp-fa... 1/6/2015 3.2.6. Identify, map and protect additional significant underwater ecological communities as critical waters. Similar to our landmass, our waters contain areas of high ecological significance. The Federal, State and local governments and agencies have placed numerous legal designations on our lands and waters to provide land use managers with data that enables better decision making. In 1992, The National Environmental Protection Agency designated the Peconic Estuary as a National Estuary recognizing the important ecological significance of the area. Other designations of town waters include the following: • USFWS Northeast Coastal Areas Study Ecological Complexes • New York Department of State Significant Coastal Fish and Wildlife Habitat • NYDEC Critical Environmental Areas • Shellfish Harvest and Seeding Areas • Peconic Estuary Program Critical Natural Resource Areas • Estuary of National Significance (Long Island Sound) A map showing the location of the ecological communities (including shellfish beds) is included as Figure 4. A complete discussion on the meaning of each designation is included as Appendix D. 3.4. Protect and restore Significant Coastal Fish and Wildlife Habitats. The Town of Southold contains twenty-one (21) Significant Coastal Fish and Wildlife Habitats (SCFWH). These habitats are indicative of high ecological value. To designate a SCFWH, the New York State Department of Environmental Conservation (DEC) evaluates the significance of coastal fish and wildlife habitat areas, and following a recommendation from the DEC, the Department of State designates and maps the specific areas. Recent additions to the program include Pipes Cove (2005) and the Goldsmith Inlet and Beach (2005). The Town of Southold recognizes the importance of protecting and enhancing these valuable habitats. A map showing the areas is included as Figure 5. A list of the Significant Fish and Wildlife Habitats and their narratives can be found at the New York Department of State website at the following web address: http://www.dos.ny.gov/comm un it ieswaterfronts/consistency/scfwhah i tats. htm I 3.5. Protect and restore New York State Department of Environmental Conservation Critical Environmental Areas. The Town of Southold contains twenty-three (23) NYSDEC Critical Environmental Areas (CEA). To be designated as a CEA, an area must have an exceptional or unique character with respect to one or more of the following: 42 • a benefit or threat to human health; • a natural setting (e.g., fish and wildlife habitat, forest and vegetation, open space and areas of important aesthetic or scenic quality); • agricultural, social, cultural, historic, archaeological, recreational, or educational values; or • an inherent ecological, geological or hydrological sensitivity to change that may be adversely affected by any change. The designations are important in review of development actions because the State Environmental Quality Review Act requires that a potential impact on the environmental characteristics of a CEA must be evaluated. A map showing the locations of CEA and SCFWH in Southold is included as Figure 5. Detailed maps of each Critical Environmental Areas and narratives can be accessed at the NYSDEC website at the following web address: http://w-vvxv.dec.nv.gov/pemiits/25153.litinl Responsible Parties: Town Planning Department Possible Partnerships: New York State Department of Environmental Conservation, US Fish and Wildlife Service, Land Preservation Department, Agricultural Advisory Committee, Stewardship Committee and other non-governmental agencies Timeline: 2015 J y Town of Southold Significant Coastal Habitats - Critical Environmental . Areas E 1 a f f. ''� ` Plum Island tJ Map Praparad by 6 2 4 Town of Southold miles Fishers Island Ge"raphk Information System May 29, 2913 srsb. Caub a Yroowp 1. $w.c. Npw , rr fro wgw��s [c.rnun mre ra,,., a suiR+. u v Figure 5. NYSDOS Significant Coastal Habitats and NYSDEC Critical Environmental Areas. Goal 4. Control and/or monitor nuisance species. The New York Department of Environmental Protection classifies a Nuisance Animal as "A wild animal that is likely to cause property damage or is persistent and perceived as an annoyance. If an animal is not causing any concern, for example, it is simply passing by, is observed only once or twice and does not cause any harm, then it should not be considered a nuisance". The department defines a Damaging Animal as "A wild animal that damages property, for example, digs up your yard, eats your landscape plants or vegetable garden, kills or threatens your livestock or pets, fouls your lawn, eats the fish in your pond, damages your home, etc." The Town does not regulate the taking of nuisance or damaging animals, however, in 2009, the Town formed a Deer Management Taskforce to address the serious health and economic consequences of deer populations. Objectives Deer Goal 5. Freshwater and Marine Habitats The NYSDEC regulates tidal or freshwater wetlands at the state level pursuant to Article 24 and Article 25 of the Environmental Conservation Law. In addition to State regulations, some of Southold's wetlands are protected under the Federal Clean Water Act, Riverhead Harbors Act of 1899, the US Army Corps of Engineers Title 33, US Environmental Protection Agency, Section 404 Permit Program. These wetlands have been identified in the National Wetlands Inventory and can include wetlands as small as one acre. The federal wetlands are defined by three criteria: type of vegetation, period of inundation, and presence of hydric soils, whereas the state designated wetlands are defined by vegetation only. More information on Town classification of wetlands can be found in Appendix B. In 2002-2003 the Town Planning office mapped both tidal and freshwater wetlands in the Town (Figure 4) Town of Southold Tidal and Freshwater Wetlands M Tidal Wetlands Freshwater Wetlands Ties map is a resotace map and does not assume any iePdatory atilorOy. The map ws {prorated to rellect wetlands of TownMde importance. and is heDosed gerierafy on datarrialm of tidal and shevater upmwetlands es pMamW M utas Town Trustees. New York Sate DepartnMrs of Emirornwsal Conservabon and ttre U.S Army Caps of Enyneersr 3 parameter, approach for haslwater wellandsl- Wellanh ware located asap serol photograplry. sort and topogr" maps with spot QouldUWwq to improve accuaty.The map is rssef it as a screennp tocl to identity areas wtwe wetlands are expected �. occur. and will be subject to sae-specdic r,..� casfirmation m coririect n "t, a land wellands apple~ Map Created: 2003 Map Updated: 2012 Map Prepared by Town of Southold Geographic Information System May 24. 2013 0 4 miles Figure 4. Tidal and Freshwater Wetlands in the Town of Southold Plum Island Fishers Island Any proposed development activities near these wetland systems require permits from both the NYSDEC Bureau of Environmental Protection (for freshwater wetlands) and the Southold Board of Trustees. Possible Funding Sources: CPF, New York State Environmental Protection Fund Timeline for Implementation: 2015 Goal 2. Protect Groundwater Quality. The protection of groundwater quality is crucial for the health of the residents and visitors of the Town. As indicated above, the Town contains two Special Groundwater Protection Areas (SPGA) for which water quality protection management strategies were developed: one area includes portions of the hamlets of Mattituck and Laurel and extends westerly to Riverhead. The second area includes portions of the hamlets of East Mattituck, Cutchogue and Peconic (Figure 3). The designation of the SGPAs was based on two considerations: "namely, that this area represents a major portion of the locally significant deep recharge and that designation could facilitate the improvement and ultimate restoration of groundwater quality" (The Long Island Comprehensive Special Groundwater Protection Area Plan, 1992). Town of Southold Special Groundwater Protection Areas Q SGPA Boundary Plum Island Y 1 Map Prepared by G 2 a Town of Soutirold'— mks Fishers Island Ge"raphk information System May 24, 2013 Figure 3. Town of Southold Special Groundwater Protection Areas United States Office of Ground Water EPA/816-R-99-014k Environmental and Drinking Water (4601) September 1999 Protection Agency ^ The Class V Underground Injection V,m*wV-E Control Study Volume 11 Aquaculture Waste Disposal Wells Table of Contents Page 1. Summary...............................................................1 2. Introduction.............................................................3 3. Prevalence of Wells ....................................................... 5 4. Wastewater Characteristics and Injection Practices ................................ 6 4.1 Injectate Characteristics .............................................. 6 4. 1.1 Injectate Data at Existing Wells ................................... 7 4.1.2 General Characteristics of Aquaculture Effluent ...................... 12 4.2 Well Characteristics................................................ 16 4.2.1 Design Features ............................................. 16 4.2.2 Siting Considerations ......................................... 17 4.3 Operational Practices ............................................... 18 5. Potential and Documented Damage to USDWs................................. 20 5.1 Injectate Constituent Properties ....................................... 20 5.2 Observed Impacts.................................................20 6. Best Management Practices ................................................ 21 6.1 Reducing Pollutant Levels in Injectate................................... 21 6. 1.1 Improving Feeding Efficiency ................................... 21 6.1.2 Chemical Use Reduction ...................................... 21 6.1.3 Technological Approaches ..................................... 22 6.2 Reducing Injectate Volume ........................................... 23 6.3 Closure; Use of Alternative Disposal Methods ............................ 23 7. Current Regulatory Requirements ............................................ 23 7.1 Federal Programs .................................................. 24 7.2 State and Local Programs ........................................... 25 Attachment A: Drugs, Chemicals, and Biotics Used in Aquaculture ......................... 27 Attachment B: State and Local Program Descriptions ................................... 37 References...................................................................44 AQUACULTURE WASTE DISPOSAL WELLS The U.S. Environmental Protection Agency (USEPA) conducted a study of Class V underground injection wells to develop background information the Agency can use to evaluate the risk that these wells pose to underground sources of drinking water (USDWs) and to determine whether additional federal regulation is warranted. The final report for this study, which is called the Class V Underground Injection Control (UIC) Study, consists of 23 volumes and five supporting appendices. Volume 1 provides an overview of the study methods, the USEPA UIC Program, and general findings. Volumes 2 through 23 present information summaries for each of the 23 categories of wells that were studied (Volume 21 covers 2 well categories). This volume, which is Wlume 11, covers Class V aquaculture waste disposal wells. 1. SUMMARY Methods employed for the controlled cultivation of aquatic organisms can vary substantially. Some aquaculture facilities use pens suspended in open water bodies, while others use systems that circulate water through tanks. Many aquaculture operations accumulate wastewater and sludge that requires removal. At dozens of such facilities in Hawaii and in several other states, this effluent is disposed via underground injection. Injected aquaculture effluent includes fecal and other excretory wastes and uneaten aquaculture food. The primary chemical and physical constituents of these wastewaters are therefore nitrogen- and phosphorus -based nutrients and suspended and dissolved solids. The effluent may also contain bacteria pathogenic to humans and chemicals, pesticides, and/or aquaculture additives. However, the incidence and concentrations of human pathogenic bacteria, chemicals, pesticides, and additives in injectate is unknown. Information on aquaculture wastewater quality industry -wide is very limited, and wastewater properties are believed to vary greatly among different aquaculture operations. Available analytical data for aquaculture injectate and aquaculture effluent suggest that the concentrations of most parameters are generally below applicable standards. Contaminants that may exceed the standards under some circumstances include turbidity and possibly nitrite and nitrate. The secondary maximum contaminant level (MCL) for chloride is also exceeded in the wastewater from some seawater -based operations, but as long as these wastes are injected to saline aquifers, they pose no threat to USDWs. The injection zone for aquaculture wastewater is characterized by relatively high porosity, as aquaculture wastewaters typically have significant suspended solids content. Seawater -based aquaculture operations in Hawaii inject wastewater into brackish or saline aquifers that flow seaward. Little information is available regarding other aquifers receiving aquaculture injectate. No contamination incidents related to aquaculture wastewater disposal have been reported. Information about the threat of contamination posed by these wells is also inconclusive. For example, in Idaho, an aquaculture well is known to inject wastewater directly into an aquifer, but the quality of the aquifer, its status as a USDW, and the resulting impacts, are unknown. The subsurface disposal September 30, 1999 system (i.e., a leaching field) known to be in use by an aquaculture operation in Maryland is situated above a Type 1 (high quality) aquifer, but no impacts have been observed. Aquaculture wells generally are not vulnerable to spills or illicit discharges. Most are located within private facilities and are not accessible to the public for unsupervised waste disposal. However, the potential exists for operators to dispose of harmful liquid wastes (e.g., waste aquaculture chemicals, or spent tank water with higher concentrations of chemicals used for temporary treatment of cultivated organisms) via aquaculture injection wells. No such cases have been reported. According to the state and USEPA Regional survey conducted for this study, a total of 56 documented Class V aquaculture waste disposal wells exist in the U.S. The great majority occur in Hawaii (51 wells, or 93 percent). The remaining documented wells are in Wyoming (2 wells), Idaho (I well), New York (1 well), and Maryland (1 well). In addition to these documented wells, as many as 50 additional wells are estimated to exist in California. Thus, the true number of aquaculture waste disposal wells in the U.S. is likely to approach 100. Given that the value of U.S. aquaculture production has grown by 5 to 10 percent per year over the past decade, and that the aquaculture industry remains the fastest growing segment of U.S. agriculture, there is some possibility that the number of Class V aquaculture waste disposal wells will increase. Programs to manage Class V aquaculture waste disposal wells vary between the states with documented or estimated wells: In California, USEPA Region 9 directly implements the Class V UIC program. In addition, under the California Water Quality Control Act, nine Regional Water Quality Control Boards coordinate and advance water quality in each region. These Boards may prescribe discharge requirements for discharges into the waters of the state under regional water quality control plans. In Hawaii, USEPA Region 9 directly implements the Class V UIC program. In addition, aquaculture waste disposal wells are authorized by individual permits issued by the state Department of Health. Class V wells are subject to siting requirements, and prohibited from operating in a manner that allows the movement of contaminants into a USDW. In Idaho, which is a Primacy State, wells greater than 18 feet deep are individually permitted, while shallower wells are authorized by rule. The state has enacted an antidegradation policy to maintain the existing uses of all ground water. departments, as well as the state Department of the Environment, can oversee aquaculture waste discharge wells. In New York, the Class V UIC program is directly implemented by USEPA Region 2. The state also implements a State Pollution Discharge Elimination System (SPDES) to protect the waters of the state, which include ground waters. Aquaculture waste disposal wells can be required to obtain an SPDES permit for discharges into ground water. Wyoming is a Primacy State and aquaculture wells are covered under a general permit under the state's Class V UIC program. The permit covers a class of operators, all of whom inject similar types of fluids for similar purposes, and requires somewhat less information to be submitted by the applicant than is required by an individual permit. The well must satisfy specific construction and operating requirements (e.g., pretreatment of wastewater). 2. INTRODUCTION The term "aquaculture" has been defined in many different ways. In addition to the international definition used by the United Nations (see text box), the term has taken a number of definitions in the United States. According to the National Aquaculture Act of 1980, 16 U.S.C. 2801, the term "aquaculture" means the propagation and rearing of aquatic species in controlled or selected environments. USEPA (1987) defines it simply as the active cultivation of marine and freshwater aquatic organisms under controlled conditions, while Buck (1999) defines the term to include both the farming and the husbandry of fish, shellfish, and other aquatic animals and plants. These definitions encompass a broad range of What is Aquaculture? According to the Food and Agriculture Organization (FAO) of the United Nations, the term "aquaculture" is defined as "the farming of aquatic organisms, including fish, molluscs, crustaceans, and aquatic plants. Farming implies some sort of intervention in the rearing process to enhance production, such as regular stocking, feeding, protection from predators, etc. Farming also implies individual or corporate ownership of the stock being cultivated" (FAO, 1997). organisms and a wide variety of production systems and facilities. Aquaculture operations across the U.S. produce more than 100 species of aquatic organisms at different life stages, although about 10 species of shellfish and finfish dominate the industry (Goldburg and Triplett, 1997). These operations utilize salt, brackish, and/or fresh waters. As the purpose of the facility can also vary, this study considers those facilities that propagate aquatic organisms for commercial purposes (e.g., for sale as food) as well as those that rear aquatic organisms for research and/or educational purposes (e.g., public display). A common attribute of all aquaculture systems is the use of water as the medium for cultivation. Aquaculture systems provide a constant supply of sufficiently clean and oxygenated water to support the cultivated organisms, and also to cavy away deoxygenated water and wastes. Systems that hold organisms within open, natural water bodies (suspended cages, net pens, or racks) rely on natural September 30, 1999 from Sea Life Park is injected into a saline aquifer that flows seaward, and is believed to pose no threat to USDWs. Chloride would only be of concern for any future sea or brackish water-based aquaculture operations that plan to inject their effluent in locations where they can affect USDWs. No aquaculture operations are known to do so at present. Table 6 indicates that the established performance standard for turbidity is exceeded by the effluent from one aquaculture operation known to inject waste into Class V wells (i.e., the fresh water fish farm monitored by the Hawaii Aquaculture Effluent Discharge Program in 1990; see Table 2). While turbidity does not have direct human health effects, the primary MCL for turbidity has been established because turbidity can interfere with disinfection and can provide a medium for microbial growth. The MCL for nitrate is exceeded in effluent from the McGill Farms (MD) operation (Table 5), but as previously noted, this effluent passes through a septic tank, where settling and some digestion and breakdown of contaminants typically occurs, prior to injection. Only the supernatant from the septic tank is injected into the subsurface disposal well. The concentration of nitrate in the supematant/injectate is unknown. It is probably well below the concentration found in the raw effluent prior to entry into the septic tank (i.e., well below the concentrations shown in Table 5), but may nevertheless exceed the nitrate MCL. All other nitrate concentrations reported for Class V aquaculture injectate are below the MCL. Although the data for aquaculture injectate presented in this section do not provide information on nitrite concentrations, effluent data from other aquaculture operations (not injecting wastes into wells) suggest that effluent from certain types of high-intensity operations (e.g., high-density shrimp farms) can contain nitrite at levels approaching the established MCL (Samocha and Lawrence, 1995). Thus nitrite concentrations are of possible concern for any future, high-intensity aquaculture operations planning to dispose of effluent via underground injection. X' 4.1.2 General Characteristics of Aquaculture Effluent As the foregoing data suggest, wastewaters from various aquaculture operations generally share a common list of primary constituents: nitrogen- and phosphorous -based nutrients, and suspended and dissolved solids. Effluent quality data for the industry as a whole are limited. Moreover, the concentrations of these constituents in effluent probably vary greatly among different aquaculture operations, depending on a number of factors such as: water management systems (i.e., flow-through or recirculating); wastewater management systems (whether treatment or settling is applied to effluents); whether low -intensity or high-intensity aquaculture is practiced; the type and size of organisms raised; feeding efficiency; and other factors. Bacteria are additional constituents of concern in aquaculture effluent. Fish wastes can contain bacteria that are known human pathogens and thus it is possible that aquaculture injectate may contain pathogenic bacteria. However, adequate data are not available to fully characterize the threat to USDWs and humans. Table 7 lists pathogenic bacteria found in fish and wastewater at aquaculture September 30, 1999 12 operations. The likelihood of such bacteria being present in wastewater, and the particular bacterial species likely to be present, varies depending on the type of aquacultural operation and species cultivated. Table 7. Human Pathogenic Bacteria Found in Fish and Water at Aquaculture Operations Pathogen Possible Effect on Humans Infection Route Salmonella sp. Food poisoning Ingestion ribrio parahaemolyticuys Food poisoning Ingestion Campilobacter jejuni Gastroenteritis Ingestion Aeromonas hvdrophila Diarrhea/septacaemia Ingestion Plesiomonas shigelloides Gastroenteritis Ingestion Edwardsiella tarda Diarrhea Ingestion Pseudomonas aeruginosa Wound Infection Dermal Pseudomonas fluorescens Wound Infection Dermal Mycobacterium fortuitum Mycobacteriosis Dermal Mycobacterium marinum Mycobacteriosis Dermal Erysipelothrix rhusiopathiae Erysipeloid Dermal Leptospira interrogans Leptospirosis Dermal Source: Austin and Austin, 1989 (as cited in Smith et al., 1994). A single set of data is available indicating microbial content in aquaculture injectate. All samples of injectate at Sea Life Park (HI) had coliform bacteria present (see Tables 3 and 6). This does not provide a useful indication of the possible presence of microbial pathogens in all types of aquaculture injectate, however. Sea Life Park raises marine mammals (for display purposes), and the microbial content in the effluent from this operation is probably very different from that of the great majority of aquaculture operations that raise non -mammal species for food. Similarly, the types of chemicals, pesticides, and additives used in aquaculture are well known, but their incidence and concentrations in aquaculture effluents are not well quantified for the industry as a whole. The use and rate of application of these materials varies significantly and depends on factors such as the species raised, culture intensity (e.g., organism density), water quality, and operation type. Thus, the incidence and concentration of these materials in wastewaters is expected to vary considerably. Three antibiotics are approved for use in U.S. aquaculture: oxytetracycline, sulfadimethoxine- ormetoprim, and sulfamerazine. However, the Federal Drug Administration's (FDA) new drug -use regulations allow other antibiotics and other drugs to be used under certain specified and controlled September 30, 1999 13 conditions (USFDA, 1996). FDA regulations include certification of proper drug usage and drug residue testing (FDA also requires an environmental impact review prior to drug approval). The approved drugs can be used only for certain fish species, and withdrawal times prior to harvest are specified on drug labels (USFDA, 1998). These regulations reduce the likelihood that these drugs will be present in aquaculture effluent at levels toxic to humans. However, as these regulations are focused on concentrations of drugs in the edible product, they can not be relied upon to maintain the concentration of drugs in wastewater within drinking water standards. Fish hormones are sometimes used to induce maturation, spawning, and sex reversal for fish in hatcheries. FDA -approved color additives, carotenoids (also found naturally in many vegetables), may be fed to farmed salmon and trout to produce a pink/orange flesh that consumers prefer. Vitamins and minerals may also be added to feed to fulfill fish nutrition requirements (Goldburg and Triplet, 1997). Drugs approved by FDA for use in aquaculture, as well as drugs of low regulatory priority at FDA, are listed in Attachment A of this volume. USEPA regulations allow the use of numerous herbicides, algaecides, and fish toxins (not necessarily common) in aquaculture systems where fish are raised for food. For example, fungicides may be used to ensure the healthy development of fish eggs. The USEPA-approved algaecides, herbicides, and other pesticides are also listed in Attachment A of this volume. Finally, veterinary biologics (e.g., vaccines) are used in aquaculture for the prevention, diagnosis, and treatment of animal diseases. Preventive and therapeutic veterinary biologics act on or in concert with the body's immune system to provide or enhance resistance to disease. Diagnostic veterinary biologics are used to detect the presence of a disease organism or diseased cells as well as to detect immunity in the fish against disease organisms. The use of biologics in aquaculture is regulated by USDA's Animal and Plant Health Inspection Service. Biologics approved by USDA for use in aquaculture are also listed in Attachment A of this volume. The FDA-, USDA-, and USEPA-regulated chemicals listed in Attachment A are not necessarily present in aquaculture injectate. For example, some of the chemicals may not be used in closed systems, or may be applied in a manner preventing them from being in wastewater (i.e., they may degrade and break down before reaching the effluent). The herbicides listed in Attachment A that are used for weed control are generally used in large water bodies supporting open aquaculture operations that do not collect or manage wastes. These herbicides are therefore outside the scope of concern for aquaculture waste disposal wells. Drugs and pesticides regulated by FDA and USEPA that are likely to be present in the effluent of some aquaculture operations, and could conceivably be present in current and future aquaculture injectate, are summarized in Table 8 below. September 30, 1999 14 Table 8. Possible Chemical Contaminants in Aquaculture Effluent FDA -Approved Drugs Used as additives to tank water (likely to be in effluent in some operations): • Tricaine methanesulfonate Sulfadimethoxine and ormetoprim • Formalin Sulfameriaine • Oxytetracycline Used as solutions into which fish are dipped briefly (may be disposed of via wastewater disposal system): • Acetic acid Povidone iodine compounds • Calcium oxide Sodium bicarbonate • Fuller's earth Sodium sulfite • Magnesium sulfate Urea • Papain Tannic acid Drugs of Low Regulatory Priority for FDA Used in Aquaculture Generally used as additives to tank water (could be present in effluent in some operations): • Calcium chloride Potassium chloride • Hydrogen Peroxide Sodium chloride USEPA-Registered Pesticides For Aquaculture Algaecides, generally added to tank water (likely to be present in effluent of some operations, but in instances of high BOD, copper compounds are likely to be complexed with suspended organics, and thus may become biologically unavailable): • Chelated copper Elemental copper • Copper (inorganic compounds) Copper sulfate pentahydrate • Endothall Herbicides, possibly used as additives to some tanks (may be present in the effluent from some operations): • Acid blue and acid yellow Diquat dibromide • Dichlobenil Glyphosate Fish toxins, generally added to tank water (likely to be present periodically in effluent of some operations but not likely in tank or raceway systems): • Antimycin • Rotenone As is the case with bacteriological contamination, however, data adequate to quantify the incidence and concentrations of the above materials in aquaculture effluent on an industry -wide basis are not available. The presence and concentration of these chemicals and biologics is expected to vary greatly from operation to operation, and from one period to another within individual operations. High concentrations of some chemicals used in aquaculture may be toxic to humans. However, the use of these materials is regulated to ensure safety of the aquaculture product, and this regulation may also ensure that concentrations of these materials in aquaculture waters and effluents are safe. September 30, 1999 15 Primary drinking water standards have been established for four of the materials listed in Table 8, and a draft health advisory has been issued for one additional drug. These standards and the advisory are presented in Table 9. These constituents, since they are approved for use in aquaculture, could conceivably pose a threat to human health if introduced into USDWs in concentrations above these thresholds. However, adequate data are not available to estimate the likelihood of such contamination. Table 9. Drinking Water Standards for Chemicals Used in Aquaculture Chemicals/ Pesticides Primary Standards Health Advisory Levels For 70 -kg Adult Cancer Group' Regulatory Status MCL (mg/1) Status Noncancer Lifetime (mg/1) mg/I at 10'0 Cancer Risk Copper Final 1.3 _ _ D Diquat Final 0.02 - 0.02 D Endothall Final 0.1 Final 0.1 D Formaldehyde' - Draft 1 - B13 Glyphosate Final 0.7 Final 0.7 - E 1 The categorization of cancer group according to the carcinogenic potentials of chemicals: B1 - probable human carcinogen, based on limited evidence in humans, and sufficient evidence in animals. D - inadequate or no human and animal evidence of carcinogenicity. E - no evidence of carcinogenicity in at least two adequate animal tests in different species or in adequate epidemiologic and animal studies. ' The active drug used in aquaculture is formalin, an aqueous solution of formaldehyde. 3 Carcinogenicity based on inhalation exposure. Source: USEPA, 1990. 4.2 Well Characteristics 4.2.1 Design Features Specific design features of aquaculture waste disposal wells vary by site in order to account for local hydrogeologic conditions. However, based on currently available inventory data, two well types are most frequently used in the U.S.: vertical cased wells and shallow subsurface disposal systems. Vertical cased wells are more numerous, and consist of a hollow casing installed vertically into the ground. The well casing is impermeable down to a specified depth, below which the casing is perforated to allow fluids to diffuse into the surrounding stratum or aquifer. The majority of case wells in use are less than 100 feet in depth; these usually have a diameter of approximately 8 inches. However, some are drilled to a depth of over 100 feet, and are typically 12 to 20 inches in diameter. September 30, 1999 16 The majority of the injection wells in Hawaii are shallow cased wells with concrete walls (for design details, see USEPA, 1987). The injection well at Ten Springs Fish Farm in Idaho is a deep cased well with a 12 -inch diameter drill hole and a depth of 180 feet. It is cased with 5 -mm steel and sealed at the top with a'/4 -inch screen. A shallow subsurface disposal system is in use at McGill Farms in Maryland. This system is essentially a standard septic system with leaching field. Classified as a Class V injection well under the ground water permit program of the Maryland Department of the Environment, this system consists of two septic tanks, from which drain pipes run underground to perforated pipes lain in subsurface trenches filled with gravel. The septic tanks are constructed of concrete and each has a capacity of 1,500 gallons. Although no further information was available on the McGill Farms system, Hartford County Health Department (HCHD) staff indicated that this system conforms in design to standard septic systems in the county (Browning, 1999). According to HCHD regulations for such systems, the wastewater from the septic tanks is distributed via a distribution box to a series of pipes buried in trenches. The trenches surrounding the pipes are typically between 35 and 100 feet long, 2 feet wide, and 10 feet deep. Each trench is filled with gravel to within 2 feet of the ground surface. Perforated pipe is laid on top of this gravel, and is covered by several more inches of gravel. The trench is then filled to the ground surface with original soil from the site. The perforated pipes that release effluent to the leaching field are at least 6 inches but no more than 2 feet below the ground surface, and are inclined at no more than 4 inches per 100 feet. The leaching field consists of several pipes in trenches at least 8 feet apart. HCHD requires that septic systems be located at least 15 feet from any property line, 75 to 100 feet from any ground water withdrawal wells, and 150 feet from wells that are below the grade of the septic system. A septic system is also used for aquaculture effluent disposal at the Oneida Fish Hatchery in New York. Detailed information regarding the design of this leach field was not available for this report. For information regarding the basic operational practices at this facility, see Section 4.3. Information about the design of the aquaculture waste disposal wells in Wyoming and California was not available for this report. 4.2.2 Siting Considerations Hydrogeology is an important factor that influences both the likelihood that injectate from aquaculture waste disposal wells will affect USDWs, and the performance of injection wells themselves in disposing of wastewater. Permeable receiving formations comprise the most favorable injection formation for aquaculture effluent, due to the high solids content of the effluent. Low -permeability receiving formations can result in clogging and failure of aquaculture injection wells. However, these same factors that contribute to good well performance also increase the mobility of injectate within the receiving strata, and the likelihood that injectate will ultimately reach any nearby or underlying aquifer (if no impermeable barriers exist between the injection point and the aquifer). September 30, 1999 17 Most of the injection wells in Hawaii, including aquaculture waste disposal wells, are located in the coastal region (seaward of the saltwater intrusion boundary) and release injectate directly into brackish or saline aquifers (Peterson and Oberdorfer, 1985). State officials believe that these wells pose no threat to USDWs, as the flow of the receiving saline aquifers is seaward, carrying injectate away from inland USDWs. The ground water table at these sites usually lies a few meters below the ground surface, and water table fluctuations resulting from ocean tides, stones, and seasonal changes in ground water recharge can significantly affect injection well performance (although USDWs remain unthreatened). The aquaculture waste disposal well in Idaho is located in highly fractured basalt and discharges in such close proximity to the surface water discharge point that contaminants are adequately addressed through the NPDES permit requirements (Tallman, 1999). The aquaculture waste disposal well (leaching field) in Maryland is situated above an aquifer 91t" classified as a `Type 1" aquifer, meaning that the quality of the water in the aquifer is excellent. The upper boundary of this aquifer is approximately 48 feet below the ground surface, or 38 feet below the bottom of the leaching trenches? Information regarding the hydrogeology at the aquaculture waste disposal wells in Wyoming, New York, and California was not available for this report. 4.3 Operational Practices Available data indicate that operational practices could vary significantly among aquaculture waste disposal wells depending on various factors, including the hydrogeologic conditions at the well site, the state where the well is located, type of well, the nature of aquaculture activity, and the availability of other waste disposal options. This section describes operations at the systems for which information is available. In Hawaii, aquaculture injection wells are used as a primary means of waste disposal, with a few wells used as standby wells or for backup drainage. Recorded pumping rates for individual wells range from 0.5 to 6 million gallons per day (gpd) (Prader, 1992). Uehara (1999) reports that at the two Keahole Point facilities, effluent discharge rates of are 3,000 gpd and 5,760,000 gpd (for all wells combined), respectively. Wells at the Oceanic Institute are permitted an aggregate flow of 80,000 gpd, and those at Sea Life Park are permitted a flow of 18,008,000 gpd. Unlike pressurized wastewater wells, aquaculture injection wells are usually gravity fed. The main operational concern is clogging due to poor site selection and a lack of maintenance. Clogging 2 State data indicate 39 drinking water wells within % mile of the operation. Fourteen of these wells range in depth from less than 100 feet to 150 feet, suggesting that they may tap the same shallow aquifer that underlies the aquaculture waste disposal system. The remaining wells range from 150 to over 350 feet deep, and may or may not tap this same aquifer. September 30, 1999 18