Florida Water Resources Journal - February 2017 by Florida Water Resources Journal

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Michael Delaney Rick Harmon Patrick Delaney Buena Vista Publishing

Published by BUENA VISTA PUBLISHING for Florida Water Resources Journal, Inc. President: Richard Anderson (FSAWWA) Peace River/Manasota Regional Water Supply Authority Vice President: Greg Chomic (FWEA) Heyward Incorporated Treasurer: Rim Bishop (FWPCOA) Seacoast Utility Authority Secretary: Holly Hanson (At Large) ILEX Services Inc., Orlando

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Websites Florida Water Resources Journal: www.fwrj.com FWPCOA: www.fwpcoa.org FSAWWA: www.fsawwa.org FWEA: www.fwea.org and www.fweauc.org Florida Water Resources Conference: www.fwrc.org Throughout this issue trademark names are used. Rather than place a trademark symbol in every occurrence of a trademarked name, we state we are using the names only in an editorial fashion, and to the benefit of the trademark owner, with no intention of infringement of the trademark. None of the material in this publication necessarily reflects the opinions of the sponsoring organizations. All correspondence received is the property of the Florida Water Resources Journal and is subject to editing. Names are withheld in published letters only for extraordinary reasons. Authors agree to indemnify, defend and hold harmless the Florida Water Resources Journal Inc. (FWRJ), its officers, affiliates, directors, advisors, members, representatives, and agents from any and all losses, expenses, third-party claims, liability, damages and costs (including, but not limited to, attorneys’ fees) arising from authors’ infringement of any intellectual property, copyright or trademark, or other right of any person, as applicable under the laws of the State of Florida.

News and Features 8 22 25 26 28 54

Water Infrastructure Improvements for the Nation Act Passed and Signed 2017 FWPCOA Officers and Committee Chairs List FSAWWA Drop Savers Contests FSAWWA Operator Awards Reducing Chlorine Costs and Improving Disinfectant Performance at a Water Reclamation Facility—Dave Hoover and Bob Bigus News Beat

Technical Articles 4

City of Tampa Augmentation Project—Brad Baird, Chuck Weber, Seung Park, David Ammerman, and Mark McNeal

16 34 46

Aquifer Storage and Recovery System Enhancement Through Reduced Operating and Capital Costs—Jeffrey Poteet, Bruce Weinstein, and John Mayhut Who Needs Pretreatment? Not Orange County Utilities’ Operational Aquifer Storage and Recovery—Mary Fickert Thomas, Kim Kunihiro, Kathy Traexler, and Mark Johnston Water Quality and Supply Issues? There’s A Wetland for That!—Chris Keller

Education and Training 9 27 31 45 47 51

Florida Water Resources Conference AWWA: Your Information Resource CEU Challenge FWPCOA Online Training Institute TREEO Center Training FWPCOA Training Calendar

Columns 24 32 37 38 40 42 44 54

C Factor—Scott Anaheim Reader Profile—Mike Darrow Test Yourself—Ron Trygar FSAWWA Speaking Out—Grace Johns Process Page: City of Plant City Advanced Wastewater Treatment Plant—Tim Ware Spotlight on Safety—Doug Prentiss Sr. FWEA Committee Corner—Laurel Rowse FWEA Focus—Lisa Prieto

Departments 43 56 59 62

New Products Service Directories Classifieds Display Advertiser Index

Volume 68

ON THE COVER: Florida Power & Light evaluated several water sources to support two power units at its Turkey Point Nuclear Generating Station in Homestead in search of the best water alternative to cool and process 130 mgd with minimal environmental impact. After considering 16 sources, and whittling that number down to four, the company decided to use reclaimed water. (photo: Florida Power & Light)

February 2017

Number 2

Florida Water Resources Journal, USPS 069-770, ISSN 0896-1794, is published monthly by Florida Water Resources Journal, Inc., 1402 Emerald Lakes Drive, Clermont, FL 34711, on behalf of the Florida Water & Pollution Control Operator’s Association, Inc.; Florida Section, American Water Works Association; and the Florida Water Environment Association. Members of all three associations receive the publication as a service of their association; $6 of membership dues support the Journal. Subscriptions are otherwise available within the U.S. for $24 per year. Periodicals postage paid at Clermont, FL and additional offices.

POSTMASTER: send address changes to Florida Water Resources Journal, 1402 Emerald Lakes Drive, Clermont, FL 34711

Florida Water Resources Journal • February 2017

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City of Tampa Augmentation Project Brad Baird, Chuck Weber, Seung Park, David Ammerman, and Mark McNeal he Howard F. Curren Advanced Wastewater Treatment Plant (plant) at the City of Tampa (city) has a permitted capacity of 96 mil gal per day (mgd), making it the fourth largest treatment plant in the state of Florida. Current flows are approximately 65 mgd and a portion of this flow, approximately 10 mgd on an annual average basis, is delivered to the south Tampa area reclaimed system for the following uses: as residential and commercial irrigation, at Tampa International Airport for cooling tower use, at the MacKay Bay refuseto-energy facility for various purposes, and on-

site at the plant. The remaining flow, averaging over 50 mgd, is discharged to Tampa Bay. The city and the Tampa Bay area are growing and in need of additional water supplies. Dual distribution systems have been very successful in reducing potable water demands, but are expensive to construct and disruptive to install in the city's built-out service area. The seasonal variations in irrigation demands also make it difficult to achieve beneficial use of the available reclaimed water supply. In June 2016 the city initiated the Tampa Augmentation Project (TAP). This project is

Brad Baird is public works and utilities services administrator, Chuck Weber is water department director, and Seung Park is chief engineer with City of Tampa. David Ammerman is vice president with Carollo Engineers in Tampa, and Mark McNeal is chief executive officer with ASRus in Tampa.

considering two alternatives to initially deliver up to 20 mgd of reclaimed water for regional beneficial reuse by improving groundwater and surface water levels, which in turn will allow additional surface water withdrawals by the city or Tampa Bay Water (TBW). The TAP feasibility study is cofunded by the Southwest Florida Water Management District (district). This article will summarize the tasks that will go into determining the feasibility of the TAP alternatives.

Existing Regional Water Supply System

Figure 1. City of Tampa existing public access reuse system.

Figure 2. Regional potable water supply system considered in the Tampa Augmentation Project.

The city is a member government of TBW, which is a regional water supply authority; however, Tampa's primary source of potable water is from the Hillsborough River Reservoir. In addition to water provided by the reservoir, the city can receive additional raw water supplies Continued on page 6

Figure 3. Alternative 1 will develop natural treatment systems on property owned by the Southwest Florida Water Management District.

February 2017 â&#x20AC;˘ Florida Water Resources Journal

Continued from page 4 from the Tampa Bypass Canal through the Harney Canal if needed to meet potable water demands. The city may also purchase finished water from TBW through an interconnect between the potable water systems. Both raw water and potable water can also flow from the city's reservoir and finished water distribution systems back to TBW to provide additional water resources to the region, if this is needed. An important element of the TAP project will be to determine how this new water resource can be integrated into the existing regional water supply. Alternative One The first TAP alternative considers construction of a 15-mi-long transmission pipe from the plant to property owned by the district. Facilities at the district site may include constructed and natural wetlands, as well as engineered rapid infiltration systems. Reclaimed

Figure 4. Clay encountered on Southwest Florida Water Management District property.

water delivered to the site will travel both above and below the land surface to the Tampa Bypass Canal, which is part of the regional surface water supply system. Ultimately, any additional flows to the canal can be diverted to the city's Hillsborough River Reservoir via the Harney Canal, thereby increasing raw water availability to the city. Status of Alternative One Investigations The TAP investigations have been underway for approximately six months. Field investigations were initiated soon after notice to proceed, and preliminary hydrogeologic information and the results of environmental assessments are becoming available on the Alternative 1 site. A total of 19 borings from land surface to the top of the Floridan aquifer have found a consistent confining layer throughout the site. As shown in Figure 4, this clay layer presents a challenge with regard to constructing rapid infiltration basins as a means of providing additional treatment through soil aquifer treatment (SAT). Ecological assessments of the wetlands on the site have also determined that they are unlikely to be considered hydrologically altered by the Florida Department of Environmental Protection. Such a determination is important as it establishes the maximum allowable reclaimed water loading to the wetlands. Loading rates to wetland systems, which are found to be in their natural state and not in need of rehydration, can only receive approximately one third of what would be allowed for wetlands in need of rehydration. The TAP team continues to assemble the results of the field investigations, which will feed into a groundwater model. A final report assessing the feasibility of using the districtâ&#x20AC;&#x2122;s property to augment regional surface water sup-

Figure 5. Alternative 2 will consider development of an aquifer recharge/recovery system.

February 2017 â&#x20AC;˘ Florida Water Resources Journal

plies is scheduled to be completed in October 2017. Alternative Two The TAP Alternative 2 will also add to the regional water supplies, but use a different means to reintroduce reclaimed water into the Hillsborough River Reservoir or to the raw water intake system of the David L. Tippin Water Treatment Facility (facility). The second alternative will use aquifer recharge/recovery wells. In this alternative, reclaimed water will be injected into the Avon Park formation, allowing for permitted withdrawals from the overlying Suwanee aquifer, increasing potable water supplies for the region. Notable differences between Alternative 1 and Alternative 2 include the fact that the transmission piping to the Alternative 2 system is approximately half of what is needed for Alternative 1. Of equal importance, recharge of the Avon Park aquifer can continue independently of conditions at the surface. This will not be the case for Alternative 1, where the delivery of reclaimed water would be suspended in periods of high rain fall. In addition, Alternative 2 will provide a transmission pipeline from the plant essentially to the facility, setting the city up for direct potable reuse in the future. Status of Alternative Two Investigations An important element of the Alternative 2 field investigations will be assessing the aquifers available for recharge and recovery within the corridor shown in Figure 5. In order to accomplish this, a series of three cores will be taken to depths of approximately 900 ft. This will include collecting continuous cores from approximately 200 ft through completion of the core, and pump tests every 50 ft to evaluate aquifer characteristics. As with Alternative 1, the informa-

Figure 6. The first of three cores associated with TAP Alternative 2 is almost complete.

Figure 7. Example of the Tampa Augmentation Project public information program.

tion collected from these cores will be used to develop a groundwater model to help evaluate how well the recharge/recovery system will serve to provide additional water supplies to the city. The photograph in Figure 6 shows the work on the first of three cores to be taken as part of the TAP project. In addition to the analysis discussed previously, water quality samples were taken from the proposed recharge and recovery zones and a complete suite of primary and secondary water quality standards is being run on the samples; however, the results of this analysis have not come back from the laboratory. The project team is also using a handheld probe to take continuous measurements of pH, oxidation-reduction potential, dissolved oxygen, conductivity/salinity, and temperature throughout the depth of the cores.

Other Tampa Augmentation Project Investigations Concurrent with the field investigations, the project team will investigate the improvements required at the plant to support the TAP alternatives, develop a transmission pipe route analysis for both alternatives, inventory the institutional and regulatory elements of the project, and initiate public outreach efforts. The institutional and regulatory evaluations will inventory the local, state, and national entities that may impact TAP. The public outreach efforts raise interesting questions in that no project has been selected and so there are no details to provide to the public; however, planning for interacting with the public has begun, and a consistent, accurate message is needed in the event questions arise regarding how the city is planning to meet future potable water demands. In the near term, one of the most likely interactions with the public and TAP comes with

Figure 8. Notifications posted at a billboard on district property prior to starting field investigations.

the field crews working on the district property for Alternative 1 and the cores being done for Alternative 2. Interaction with the public is particularly likely for Alternative 1 as the district property currently serves as a park and is being used for mountain biking and hiking. To be proactive in communicating with any persons approaching the field crew and asking about these activities, the TAP team developed a notice that was posted on a billboard at the entrance to the park (Figures 7 and 8) and developed a quick-facts card, which the field crews carry in the event they are asked questions about the project. With the fieldwork essentially complete on the district property, interaction with the public has been minimal, but the proactive approach to addressing any questions that might come up was the preferred strategy.

Summary and Look Ahead The TAP project was authorized in June 2016 and is scheduled to be completed in January 2018 (Figure 9). The project team is proceeding with an investigation of both TAP alternatives. With the completion of fieldwork and subsequent groundwater modeling, the critical metric of how much new water each option will provide to the region will be developed for the natural treatment systems proposed on district property (Alternative 1) and the aquifer recharge/recovery strategy (Alternative 2). Combining the "yield" of each alternative with its associated costs will result in a calculation of dollars per gallon of new water provided. These results will then be compared to the costs of other alternative water supplies now being considered in the Tampa Bay area. S

Figure 9. Tampa Augmentation Project schedule. Florida Water Resources Journal â&#x20AC;˘ February 2017

Water Infrastructure Improvements for the Nation Act Passed and Signed President Obama has signed the Water Infrastructure Improvements for the Nation (WIIN) Act, which was passed by the House and Senate earlier last month. The WIIN Act legislation was originally called the Water Resources Development Act of 2016, but was renamed after incorporating two additional sections. The act contains three sections: water resource development, Water and Waste Act of 2016, and natural resources. Title I of the law authorizes water resource development projects, including new studies and construction. All of the chief reports submitted to committees since the last report received authorization. By relying on the chief reports, the committee was able to circumvent the ban on earmarks. The act fully offsets new authorizations by deauthorizing projects that were never constructed. Title II of the law, the Water and Waste Act of 2016, addresses drinking water safety, particularly in small and economically disadvantaged communities, an issue that became a priority as a result of the water contamination crisis in Flint, Mich. The law also addresses disposal of coal ash or coal combustion residuals by establishing state and federal permit programs, while giving states the authority to develop their own rules within specified limits for disposal of coal ash. Title III of the law addresses natural resources issues, including updates to outdated statutes and policy changes to improve water storage for California and the West. This section of the law also resolves long-running water rights disputes with several Indian tribes and provides authority to improve flood protection infrastructure for certain Indian communities, while also expediting repair of water irrigation projects owned by the tribes. The following are significant provisions of Title I with regard to water resource development projects: S Requires the Corps of Engineers to conduct an inventory and assessment of breakwaters and jetties protecting harbors and inland harbors. S Authorizes the Corps to maintain federally authorized harbors of refuge and to restore and maintain the authorized dimensions of the harbors. S Attempts to address the imbalance of funding from the harbor fee for donor and receiver ports. S Authorizes the Corps to allow nonfederal entities to dredge authorized federal projects and be reimbursed by the federal government for their costs. S Prioritizes the expedited updating of water control manuals for control structures in states suffering from drought emergencies. The law also authorizes the Corps to consider increasing water supply and storage at federal projects, except for resources in the Upper Missouri River, the Apalachicola-Chattahoochee-Flint river system, the Alabama-Coosa-Tallapoosa river system, and the Stones River.

February 2017 • Florida Water Resources Journal

S Encourages beneficial use of dredged material by authorizing the Secretary of the Army to construct 10 pilot projects. The secretary is also authorized to establish regional sediment management teams. S Authorizes railroads to fund the expedited review of permit applications. Natural gas companies and public utilities already have this authority. S Allows nonfederal entities to receive credit or reimbursement for the construction of a discrete segment of a federal flood damage reduction project. S Requires the Corps to establish a publicly available database of maintenance dredging carried out by the Corps with internal assets or contractors. S Requires the Corps to make publicly available all data in the Corps’ custody on water resources development projects, including information on the planning, design, construction, operation, and maintenance of these projects, as well as on water quality and water management of projects owned, operated, or managed by the Corps. S Requires a report on foreign manufactured items used in Corps projects. S Amends section 14 of the Rivers and Harbors Act of 1899 (30 Stat. 1152, chapter 425; 33 U.S.C. § 408) to provide for concurrent National Environmental Policy Act (NEPA) review of Section 408 applications. This provision is a continuation of recent attempts by Congress to expedite 408 permits. S Authorizes the use of the plant replacement and improvement revolving fund to pay for the construction of district headquarters for both the Buffalo and New England Districts. S Prohibits the Corps from receiving consideration for an easement across water resources development project land for the electric, telephone, or broadband service facilities of nonprofit organizations eligible for financing under the Rural Electrification Act of 1936. S Places limitations on the disposal of dredged material by requiring the Corps to follow state water quality standards approved by the administrator of the U.S. Environmental Protection Agency under section 303 of the Federal Water Pollution Control Act (33 U.S.C. § 1313). This section will likely prohibit open water disposal of dredged material from the Cuyahoga River in Ohio, which has been at the center of a dispute between the Corps and Ohio regarding the disposal site for dredged material from the upper reaches of the River. S Authorizes 30 new studies with additional authority and emphasis given to studies that drew special interest from Congress. S Deauthorizes several project features and indicates that specific projects or portions thereof are not subject to the federal navigational servitude. While these provisions are not considered “earmarks,” they are specific to certain projects. S The law authorizes the construction of 43 projects around the Unites States. S

February 2017 â&#x20AC;¢ Florida Water Resources Journal

Florida Water Resources Journal â&#x20AC;¢ February 2017

February 2017 â&#x20AC;¢ Florida Water Resources Journal

Florida Water Resources Journal â&#x20AC;¢ February 2017

February 2017 â&#x20AC;¢ Florida Water Resources Journal

Florida Water Resources Journal â&#x20AC;¢ February 2017

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Aquifer Storage and Recovery System Enhancement Through Reduced Operating and Capital Costs Jeffrey Poteet, Bruce Weinstein, and John Mayhut History of the Aquifer Storage and Recovery System Marco Island Utilities (MIU) was purchased by the City of Marco Island (island) from Florida Water Service (FWS) in November 2003. The MIU provides potable water, reclaimed water, and sanitary sewer service for all of the residences and businesses on the island and two small communities two miles north of it. Marco Island is 24 sq mi in area and is one-half mi off the coast of Florida in the Gulf of Mexico, about 15 mi south of the City of Naples. On the island there is no developable fresh water; potable water is produced at two water treatment plants (WTP): the North Water Treatment Plant (NWTP) and the South Water Treatment Plant (SWTP). The NWTP currently uses a lime softening process to soften fresh water (i.e., salt concentration about 500 parts per million [ppm]) from the source water facility (SWF), formerly known as Marco Lakes, located nine mi north of the island. Figure 1 is an aerial

view from the SWF to Marco Island showing the main facilities of MIU, including the two WTPs and the Marco Island wellfield, also known as the reverse osmosis (RO) wellfield. The 208-acre SWF has two lakes and seven aquifer storage and recovery (ASR) wells that provide the fresh water for treatment at the NWTP to produce potable water and to supplement reclaimed water at two golf courses. Figure 2 shows an aerial view of the ASR wellfield. Table 1 summarizes the phases of development of the ASR wellfield to its current size of seven wells. The ASR well No. 1 began operation in 1997, and on Oct. 2, 2001, it was issued a Class V operating permit from the Florida Department of Environmental Protection (FDEP), the first ASR well in Florida to receive such a permit. The ASR wells located on the north side of the lake are set on a grid with 400-ft spacing. The ASR wellfield received a Class V operating permit in June 2010 (plus a construction permit for ASR wells No. 4 and No. 7 to be built). New groundwater modeling re-

Above: Figure 1. Map Showing Service Area and Features of the Water Supply System At right: Figure 2. Aquifer Storage and Recovery Wellfield at the Source Water Facility

February 2017 • Florida Water Resources Journal

Jeffrey Poteet is general manager of water and sewer at Marco Island Utilities in City of Marco Island. Bruce Weinstein, P.E., is a chemical engineer and John Mayhut is senior project hydrogeologist at KLJ in Ft. Myers.

sults showed that ASR wells No. 4 and No. 7 would not have to be constructed because the existing seven wells can successfully operate at higher flow rates to meet the planned capacity of 13.5 mil gal per day (mgd). The ASR system is a nationally recognized project and has won the 2010 grand prize for environmental sustainability from the American Academy of Environmental Engineers, the National Ground Water Association’s 2010 outstanding groundwater project award, and the 2011 president’s award for environmental sustainability from the National Association of Environmental Professionals.

Wellfield Operations Pretreatment of Water Stored in the Aquifer Storage and Recovery Wellfield The stored water is pretreated to protect the wells from plugging and meet regulatory requirements; however, when the water is recovered it is essentially raw water, since it must undergo full treatment at the NWTP, just like the water withdrawn from the lakes and pumped to the NWTP to produce potable water. The 9 mgd (or more) injected in the ASR wellfield is pumped through a pretreatment plant before injection into the ASR wells. Figure 3 shows the pretreatment plant that consists of two 12-ft-diameter and four 8-ft-diameter pressure filters with filtration beds of sand and charcoal. After the water is filtered, sodium hypochlorite and ammonium sulfate are added to produce a concentration of about 0.7 ppm of monochloramine disinfectant, and then the pH is reduced from about 7.5 to 7 with carbon dioxide gas to prevent precipitation of calcium carbonate on the borehole walls in the storage zone.

No Long-Term Issue With Arsenic in Recovered Water The release of arsenic into the recovered water causes the oxygen in the water to react with the small amount of pyrite (about 0.23 wt percent) that contains the arsenic (about 0.14 wt percent of the pyrite) and forms ferric oxyhydroxide. During recovery, ions in the water flow over and react with the oxyhydroxide to form iron sulfide and also release the arsenic into the water.

Figure 4 shows the trend of arsenic in the recovered water from the ASR wells No. 2 and No. 3 (typical of all the wells). The reason the arsenic reduces to nondetect concentration after three cycles in MIUâ&#x20AC;&#x2122;s ASR wellfield is a result of the relatively high concentration of dissolved organic compounds (about 15 ppm) compared to the dissolved oxygen concentration of about 5 to 6 ppm. The oxygen in the water most likely forms an aerobic zone near the well; however, Continued on page 18

Aquifer Storage and Recovery Wellfield Operation During the rainy season (typically mid-June to the end of November) Henderson Creek Canal (HCC), which borders the east side of the SWF, has a high inflow of stormwater runoff. Correspondingly, bank infiltration from the HCC into the two lakes is sufficiently high during the rainy season to allow the withdrawal from the two lakes to simultaneously meet the demand of about 6 mgd to the NWTP and about nine 9 mgd to fill the ASR wellfield. The maximum realistic storage rate is 13.5 mgd. The ASR wellfield storage zone is between two clay layers at 730 and 780 ft below ground surface and the native water has a chloride content of about 2,900 ppm. The stored water (with a chloride content of 70 to 150 ppm) is maintained at about one bil gal in a bubble shape with a diameter of about 4,000 ft. During the dry season (December to June) the water elevation in the lakes is often low and it limits the water withdrawal rate. The additional flow (2 to 5 mgd) needed to meet the demand is made up by recovering water from the ASR wellfield. Good Geology Contributes to the Success of the Wellfield The storage zone between 730 to 780 ft below grade is homogenous limestone that ranges from vary pale orange to yellowish gray. This limestone has a sponge-type structure, with good to excellent apparent moldic porosity. Fractures that would conduct stored water far from the wells and make it difficult to recover were not evident. Florida Water Resources Journal â&#x20AC;˘ February 2017

Continued from page 17 the high organic concentration will react with all the oxygen to limit the size of the aerobic zone. Without oxygen, the arsenic in the pyrite does not dissolve into the water.

Benefits of the Aquifer Storage and Recovery Wellfield: A Third Water Supply Marco Islandâ&#x20AC;&#x2122;s population ranges from 15,000 in the summer months to more than 40,000 during the winter months. Such a large variation in population causes the monthly daily average water demand in the summer months to be as low as 5.5

Table 1. Aquifer Storage and Recovery Development History

Figure 3. Pretreatment System

mgd and for the winter months to be 9 mgd. This variation in water demand would be greater by about 2 mgd if it were not for the reclaimed water distribution system that provides irrigation water to customers. Table 2 lists the benefits to customers of MIU by having the ASR wellfield as a third water supply, which during the dryer months, allows MIU to meet the high demand without having to increase the withdrawal from the wellfield on the island to the point where the salt concentrations increase. A previously published paper (FWRJ, March 2013) showed that the supply wells for the SWTP had a long history of ever-increasing dissolved salt concentrations, with a few wells exceeding 18,000 ppm salt. The ASR wellfield allows MIU to reduce the annual withdrawal from the brackish water wellfield wells by 50 percent (from 4 mgd to 2 mgd), thereby stopping and even reversing the upward trend in salt concentrations, making the brackish wellfield sustainable. The large volume of stored water in the ASR wellfield has allowed the island to obtain exemptions from the South Florida Water Management District (SFWMD) from irrigation restrictions. The additional water from the ASR wellfield allows MIU to have sufficient water to provide about 60 mil gal per year (mgy) to the golf courses to supplement reclaimed water. The additional water provided by the ASR wellfield also allows MIU to send about 45 mgy into the chlorine chambers at the reclaimed water production facility (i.e., the wastewater plant on the island), which blends with the treated wastewater, thereby increasing the amount of reclaimed water available for distribution. The raw water from the Marco Lakes site must meet suspended solids standards of 5 ppm. Figure 5 shows the suspended solids meter and piping that delivers the raw water to the chlorine contact chamber. Goals of Upgrades to the System for the Future The ASR system has a 20-year operating history, going back to when upgrades were needed to ensure continued high performance and relatively low operating costs with high reliability for the next 20 years (and longer). The goals that the upgrades need to achieve are listed in Table 3. Maintain Stable Operating Performance of the Wells The most important goal of any upgrade to an ASR system is to be certain that stable operation of the ASR wells is not compromised. For example, if the filtration equipment is not inspected on a regular basis, with the goal of reducing labor costs, the potential for fouling the borehole of the wells dramatically increases.

Figure 4. Arsenic Recovery (2002-2014)

February 2017 â&#x20AC;˘ Florida Water Resources Journal

Reduce Annual Operating Cost Modifications (i.e., upgrades) to operating

Table 2. Benefits of a Third Wellfield

Figure 5. Suspended Solids Meter and Chlorine Contact Chambers

Table 3. Goals of Upgrades to Aquifer Storage and Recovery System

protocols should have the net effect of reducing overall costs. For example, the use of ammonium sulfate solutions to replace gaseous ammonia for formation of monochloramine in the injected water actually increases the cost of chemicals, but it decreases maintenance costs, with a net effect of a reduction in annual operating costs. Another example is the reduction in analytical sampling needed to meet FDEP permit requirements. Increase Recovery Efficiency The ASR wellfield must provide a sufficiently high recovery efficiency of the stored water for the operation to be financially viable (i.e., justified). Any upgrade that could compromise the recovery efficiency needs to be carefully assessed before being implemented. Improve Reliability to Meet Demand for Recovered Water Any upgrade should not have a negative impact on the reliability of the ASR system to be able to meet the demand of recovered water. For example, backup pumps for storing water in the ASR wellfield improve the reliability to recover water since it canâ&#x20AC;&#x2122;t be recovered if the pumps fail to store water.

Upgrades Implemented for the Wellfield Improvements to the Pressure Filters The main components of the pretreatment system are the pressure filters, which were installed in pairs. The first two 8-ft-diameter filters were installed in 1997 when ASR well No. 1 started operation; one filter was operating and one was in standby mode. After about 20 hours of operation, the pressure in a filter increased from 4 to 15 pounds per sq in. gauge (psig), which automatically took that filter offline for a five-minute backwash with unfiltered water, and switched the flow to the standby filter for the next 20 hours. When ASR wells No. 2 and No. 3 were installed, another pair of 8-ft-diameter filters where installed. When ASR wells No. 5, No.

6, and No. 8 were installed in 2006, the two 12ft-diameter filters were also installed. Table 4 provides the approximate completion of each of the upgrades completed at the ASR wellfield. The backwashing continued to occur with filtered water. The backwashing of the filters was still triggered when the pressured drop across a filter reached 15 psig. The problem with the backwashing protocol was that each of the three pairs of filters, in theory, could have one filter in the backwash mode at the same time. With high flow rates of 6,000 gal per minute (gpm), the other filters online could have almost all the sand and charcoal blown out to the drainage area for the backwash water. This scenario did occur and resulted in two upgrades to the filters. This first upgrade was to have a process control consultant recode and make the necessary wiring modification so that all six filters communicated with each other; then, only one filter would be in a backwash mode no matter what the flow rate was for the injected water. This eliminated the potential to blow out the sand and charcoal in the filters. The second modification was to change the programming sequence (onoff setting) of the control valves for each filter so that the backwashing was done with filtered water. This last change slightly reduces the volume of filtered water produced each day, but it increased the time for backwash cycles.

Using Ammonium Sulfate Solution Instead of Gaseous Ammonia In 2006, when ASR wells No. 5, No. 6, and No. 8 were installed, a gaseous ammonia feed system was installed to create the disinfectant monochloramine in the injected water instead of hypochlorite, which caused the formation of trihalomethanes (THMs). In 2012, the gaseous ammonia feed system was replaced with an ammonium sulfate solution that has a much higher chemical cost (by a factor of more than three), but much lower maintenance costs and higher reliability. Reduce Annual Losses of Carbon Dioxide Installation of a second refrigeration unit on the carbon dioxide storage tank essentially eliminated losses of carbon dioxide, thereby reducing operating costs. New Aquifer Storage and Recovery Feed Pumps and Building The existing two 49-year-old, 200-horsepower (hp) ASR feed pumps (Figure 6) were replace with two new 400-hp pumps (Figure 7), with each equal to the combined flow (6,000 gpm) of the older pumps. This provided 100 percent redundancy. Each pump can also can pump more than 5,000 gpm of lake water directly to the Continued on page 20

Florida Water Resources Journal â&#x20AC;˘ February 2017

Continued from page 19 NWTP in the event the adjacent 37-year-old pump house that normally pumps lake water to the NWTP is damaged. To improve the reliability and reduce the maintenance costs of the new pumps, a new pump house (Figure 8) for the 400-hp pumps was built, which is designed to withstand wind loads of 180 mi per hour (mph). Figure 6. Aquifer Storage and Recovery Pumps During Deconstruction

Figure 7. New 400-hp Aquifer Storage and Recovery Feed Pumps

Modeling Study Reduces Capital Costs and Optimizes Stored Water A modeling study of the bubble of fresh water stored at the ASR wellfield was completed in 2014 and provided an updated estimate of the fresh water shape of the bubble. A result of the modeling was that the existing seven wells had the ability to store the maximum daily stored water of 13.5 mgd, and that the last two ASR wells No. 4 and No.7 did not have to be built, resulting in a capital savings of about $3 million in well construction and ancillary costs. Modification of the Permit Requirements for Modeling In 2015 the permit for the ASR wellfield was renewed. Given the long history of compliance, the monitoring and associated analytical costs have been reduced. Table 5 shows the reductions monitoring compared to the monitoring required before the permit was renewed. Generally, the water quality testing and monitoring increased by about 50 percent in the ASR and monitoring wells tapping the injection/production zone, and by about 75 percent in the upper monitoring zone.

Figure 8. New Aquifer Storage and Recovery Feed Pump Building

Table 4. Upgrades to Aquifer Storage and Recovery System

February 2017 â&#x20AC;˘ Florida Water Resources Journal

Planned Upgrade to Replace Lime Softening at the North Water Treatment Plant Pilot testing will soon begin to obtain the data to design the lime softening process at the NWTP with low-pressure RO membrane trains. This will have an impact on the ASR wellfield because the recovery is currently cut off at a maximum chloride concentration of 250 ppm. The RO will essentially remove about 99 percent of all the dissolved salts so the recovery limit can be increased to 500 ppm of chlorides. The net effect is that less water would have to be injected to store the same volume of recoverable water, thereby saving on injection costs.

Summary of the Results of the Upgrades Table 6 is a summary of the operating cost savings associated with the upgrades to the ASR system. Table 7 gives the operating costs for the five-year injection period (2006-2010) and the five-year recovery period (2007-2011) for the ASR system before the upgrades and what the cost would have been had all the upgrades been available. The net result is that the operating costs are reduced by about 20 percent. The power cost for storing water with the new pumps was estimated at 85 percent of the power consumption of the old pumps, but the power for recovery is unchanged. The analytical and associated labor costs for sampling were reduced based on the percentage reduction in the permit requirements. The chemical costs have

Table 5. Water Quality Monitoring Reductions

a slight increase from the higher cost of ammonium sulfate compared to ammonia and salt. The two greatest maintenance issues had been the yearly repairs to the old feed pumps and ammonia feed system, which have been mostly eliminated with the upgrades; however, while the operating cost savings is good, the real benefit is the improved reliability, since the ASR wellfield often provides 20 percent of the raw water needed by MIU.

Table 6. Operation Cost Analysis

Results A summary of the results of the upgrades, including the reduction of planned capital expenses and increased reliability, is as follows: S Modeling work showed two additional ASR wells were not needed to meet future demand ($3 million savings). S Changes to monitoring requirements and chemical feed systems reduced operating costs by about 20 percent. S Reliability to store water at high flow rates was greatly increased, which is critical since available storage time is limited. S Greatly improved reliability of the ASR feed pump. S

Florida Water Resources Journal â&#x20AC;˘ February 2017

2017 FWPCOA OFFICERS AND COMMITTEE CHAIRS For more information on officers and committee chairs, visit the association website at http://www.fwpcoa.org.

• Secretary Debra Englander (727) 892-5633 04-secretary@vwpcoa.org • Treasurer Janet DeBiasio (727) 892-5640 04-treasurer@fwcpoa.org

• Treasurer Tim McVeigh (954) 683-1432 07-treas@fwpcoa.org • Secretary-Treasurer-Elect (currently vacant)

Region 8 Region 5

CORPORATE OFFICERS • President Scott Anaheim (904) 665-8415 sanaheim@bellsouth.net • Vice-President Mike Darrow (863) 409-4256 Mdarrow99@gmail.com • Past President Tom King (321) 867-9495 Thomas.j.King-1@nasa.gov • Secretary-Treasurer Rim Bishop (561) 627-2900, ext. 314 sec-treas@fwpcoa.org • Secretary-Treasurer-Elect Kenneth Enlow (813) 226-8708, ext. 239 sec-treaselect@fwpcoa.org

REGIONAL OFFICERS Region 1 • Director (currently vacant) • Chair (currently vacant) • Vice-Chair (currently vacant) • Secretary-Treasurer Tom Walden (850)980-5161 tjwalden@cs.com

Region 2 • Director David Ashley (904) 665-8484 ashldd@jea.com • Chair Josh Parker (904) 665-6052 parkje@jea.com

• Director Stephen Utter (772) 978-5220 05-director@fwpcoa.org • Chair George Horner (772) 873-6400 GHorner@cityofpsl.com • Vice-Chair Val Santos (772) 462-1150 santosv@stlucieco.org • Secretary-Treasurer John Lang (772) 562-9176 jflang2012@gmail.com

• Director Nigel Noone (239) 565-5352 08-director@fwpcoa.org • Chair Scott Edson (239) 259-6009 08-chair@fwpcoa.org • Vice-Chair Matt Astorino (239) 677-0042 08-vice-chair@fwpcoa.org • Secretary-Treasurer (currently vacant) • Secretary-Treasurer-Elect (currently vacant)

Region 6

Region 9 • Director Scott Ruland

• Treasurer Russ Carson (321) 749-5914 jrcdillo@aol.com

• Director Dennis Godwin (561) 876-7220 06-director@fwpcoa.org • Chair Vince Munn vmunn@pbcwater.com • Vice-Chair Pat Lyles (561) 381-5354 4953lexus@comcast.net • Secretary-Treasurer Patti Brock (561) 493-6261 pbrock@pbcwater.com • Secretary-Treasurer-Elect Jessica Hill (561) 386-5839 R6Training@outlook.com

Region 4

Region 7

Region 10

• Director Renee Moticker 07-director@fwpcoa.org • Chair Nigel Harris (954) 921-3288, ext. 8741 07-chair@fwpcoa.org • Vice-Chair Pavel Plecenik (800) 639-7739 07-vice-chair@fwpcoa.org • Secretary Michael Towns (954) 921-3288 07-st-elect@fwpcoa.org

• Director Albert Montalvo (863) 528-2358 10-director@fwpcoa.org • Chair Charles Nichols Sr. (863) 581-0111 10-chair@fwpcoa.org • Vice-Chair Charles Nichols Jr. (863) 291-5763 10-vice-chair@fwpcoa.org

• Vice-Chair Larry Johnson johnlarry1953@att.net • Secretary-Treasurer Jackie Scheel (904) 665-8473 ScheJB@jea.com • Secretary-Treasurer-Elect Ralph (Andy) Bowen (904) 665-6052 bowera@jea.com

Region 3 • Director Kevin Shropshire (407) 832-2748 kshrop2000@hotmail.com • Chair Glen Shiler (712) 664-3629 03-chair@fwpcoa.org • Vice-Chair June Clark (321) 868-1240 J.Clark@cityofcapecanaveral.org • Secretary Wendell Maxwell (321) 863-6765 wendell.maxwell@brevardcounty.us

• Director Jeff DeGroot (727) 588-3769, ext.402 jdegroot@townofbelleair.net • Chair Christina Goodrich (727) 453-6741 04-chairman@fwpocoa.org • Vice-Chair Robert Case (727) 892-5076 04-vice-chair@fwcpoa.org

February 2017 • Florida Water Resources Journal

(386) 878-8976 sruland@deltonafl.gov • Chair Jamie Hope (352) 318-3321 hope2protectFLwaters@gmail.com • Vice-Chair (West) Tom Mikell 352-213-0723 • Vice-Chair (East) Brian Terry (386) 574-2181 • Secretary Jim Parrish (386) 574-2181 • Treasurer Bob Serpa (386) 574-2181 • Secretary-Treasurer-Elect Randy Cornell 386-574-1620

• Secretary-Treasurer Katherine Kinloch (863) 679-3972 catloch3@verizon.net • Secretary-Treasurer-Elect Edward Clark (863) 815-6595 10-st-elect@fwpcoa.org

Region 11 • Director Athena Tipaldos (407) 246-4086 11-director@fwpcoa.org • Chair Terri Seligman-Smith 407-254-7723 Terri.seligman@ocfl.net • Chair-Elect Kevin Young (407) 246-3089 kevin.young@cityoforlando.net • Secretary-Treasurer Scott Stoll (407) 709-8808 scottstolfwpcoa@aol.com • Secretary-Treasurer-Elect Mark Shoup (407) 599-3563 Hillashoup@hotmail.com

Region 12 • Director Gerry Schoonmaker (941) 861-0512 12-director@fwpcoa.org • Chair Patrick Murphy (813) 757-9191 12-chair@fwpcoa.org • Vice-Chair Brent Laudicina (941) 773-5551 12-vice-chair@fwpcoa.org • Secretary-Treasurer Steve Saffels (813) 757-9191 12-sec-treas@fwpcoa.org • Secretary-Treasurer-Elect John Wolfe (813) 875-2486 12-sec-treas-elect@fwpcoa.org

Region 13 • Director Arnold Gibson (386) 466-3350 Alg32024@gmail.com • Chair Mike Osborn osbornm@lcfla.com • Vice-Chair Tracey Betz betzt@lcfla.com • Secretary-Treasurer Bill Ewbank tom_ebk@bellsouth.net

STANDING COMMITTEE CHAIRS

SPECIAL COMMITTEE CHAIRS

• Awards and Citations Renee Moticker (954) 967-4230 awards@fwpcoa.org • Constitution and Rules Kenneth Enlow (813) 226-8708 const-rules@fwpcoa.org • Customer Relations Norma Corso (941) 764-4508 cust-rel@fwpcoa.org • Dues and Fees Tom King (321) 867-3042 dues@fwpcoa.org • Education Art Saey (954) 630-4433 education@fwpcoa.org • Ethics Scott Ruland (386) 878-8976 ethics@fwpcoa.org • Historical Al Monteleone (352) 459-3626 historian@fwpcoa.org • Job Placement Joan Stokes (407) 293-9465 • Membership Rim Bishop (561) 627-2900, ext. 314 membership@fwpcoa.org • Policies and Procedures Kenneth Enlow (813) 226-8708 04-director@fwpcoa.org • Program and Short Course Jim Smith (386) 878-8976 programs@fwpcoa.org • Publicity Phil Donovan (561) 966-4188 06-director@fwpcoa.org • Systems Operators Ray Bordner (727) 798-3969 sys-op@fwpcoa.org • Website Walt Smyser (954) 558-5656 webmaster@fwpcoa.org

• Audit Tom King (321) 867-3042 audit@fwpcoa.org • Exam Consultant Ray Bordner (727) 527-8121 exam@fwpcoa.org • FWRJ/FWRC Tom King (321) 867-9495 Thomas.j.King-1@nasa.gov • Legislative Tim McVeigh (954) 683-1432 legislative@fwpcoa.org • Nominating Raymond Bordner (727) 527-8121 h2oboy2@juno.com • Operators Helping Operators John Lang (772) 562-9176 oho@fwpcoa.org • Safety Peter M. Tyson (305) 797-8201 safety@fwpcoa.org • Scholarship Renee Moticker (954) 967-4230 robinson@fwpcoa.org

EDUCATION SUBCOMMITTEES CHAIRS • Backflow Glenn Whitcomb (386) 561-2100 backflow@fwpcoa.org • Continuing Education Jim Smith CEU@fwpcoa.org • Industrial Pretreatment Kevin Shropshire (407) 832-2748 03-director@fwpcoa.org • Plant Operations Jamie Hope (352) 318-3321 hope2protectFLwaters@gmail.com

• Reclaimed Water Scott Walden (407) 836-6865/(407) 375-1014 reclaimed@fwpcoa.org • Stormwater Tom King (321) 867-3042 stormwater@fwpcoa.org • Utilities Maintenance David Pachucki (727) 530-9807 ppapadave@aol.com

ADMINISTRATION • Executive Director

(currently vacant) exec-dir@fwpcoa.org • Training Coordinator Shirley Reaves (321) 383-9690 training@fwpcoa.org • Webmaster Walt Smyser (954) 558-5656 webmaster@fwpcoa.org

FWRC/FWRJ APPOINTMENTS • Trustee, 3rd Year Jeff Poteet (239) 394-5595 jpoteet@cityofmarcoisland.com • Trustee, 2nd Year Tom King (321) 867-3042 Thomas.j.King-1@nasa.gov • Trustee, 1st Year Rim Bishop (561) 627-2900 Ext. 314 rbishop@sua.com • Member Jon Meyer (239) 543-1005 08-director@fwpcoa.org • Member Scott Anaheim (904) 665-8415 sanaheim@bellsouth.net • Member Ray Bordner (727) 527-8121 h2oboy2@juno.com • Member Al Monteleone (352) 259-3924 scooter1030@embarqmail.com • Member Glenn Whitcomb (386) 561-2100 backflow@fwpcoa.org

Florida Water Resources Journal • February 2017

C FACTOR

It’s That Time of Year Again— License Renewals (Ugh!) training office and then waiting for a reimbursement check from the state treasury. Very shortly, we will be arranging direct reimbursement of a share of regional dues payments to each regional treasury. In other words, when a member renews via the FWPCOA website, the share of that member’s dues that goes back to the region will automatically be directed to its checking account—no more waiting for checks from me.

Scott Anaheim President, FWPCOA

y sincere hope is that each of you had a wonderful holiday season and are all looking forward to what the future holds in the new year. I want to begin by expressing my thanks to the FWPCOA board of directors, and all the members of the association, for your support and confidence in electing me to serve as your president for 2017. I assure each of you that I will do my best to fulfill the responsibilities of the office.

License Renewal Because the operator license renewal cycle for water treatment plant operators, wastewater treatment plant operators, and distribution system operators is rapidly coming to an end, remember that you must have the required number of continuing education units (CEUs) for renewal. All renewals must be done before May 1, 2017. May I suggest that each licensed operator double check the Florida Department of Environmental Protection (FDEP) website (http://ocp.dep.state.fl.us/default.asp) to be sure that any CEUs you may have obtained over the past two years have been posted. Don’t wait until the last moment; if you have taken a CEU course through an approved FDEP provider and your CEUs have not been posted, contact the training provider to determine why they haven’t. One thing to keep in mind is that any CEU training course that is taken must be approved through an authorized FDEP provider. There are courses out there that are being offered as CEU-approved, when in fact they are not. You may have taken an approved course in which the provider is not responsible for posting your CEUs; a list of these courses can be found on the FDEP website. If you have taken any of these courses, you must submit the CEU certificate of completion that you received at the time you took

Online Institute

the course to the FDEP office of certification programs to get the CEU credits. For your convenience, FWPCOA offers all flavors of approved courses in a number of different formats. The CEUs can be obtained by taking an online course, or if your utility has a large number of license operators in need of CEUs, the association can provide CEU training at your location for a flat fee for up to 25 persons in the class. Please check out our website at www.fwpcoa.org and click on the “Training” link, or contact our FWPCOA training office at 321-383-9690 for additional information. I look forward to the challenges before us. It has always been and continues to be the mission of FWPCOA to provide the best, most affordable training courses available to all operators in all areas in the utility industry; courses that are taught by professionals with the hands-on experience required for practical application in the real world of work, as well as preparation for licensure exams at all levels. Pick up the phone and call our training office to see how FWPCOA can meet your training needs.

New Payment System For those who are unaware, FWPCOA now allows the proceeds for credit card payments made for regional courses through www.fwpcoa.org to be sent directly to a designated regional bank account; no more processing credit card payments through the

February 2017 • Florida Water Resources Journal

The Online Institute presently has 92 active courses and 332 registered students. For the 2017 license renewal cycle, the association has sold an average of 53 online courses per month, greater than the monthly average of 41 courses sold during the 2015 cycle. There was an increase in revenue for December 2016 when compared with December 2014—$2,135 versus $1,530. The average monthly revenue for the 2017 renewal cycle remains well above that of the 2015 cycle: $2,824 per month versus $2,284 per month, respectively. Please continue to advise your members of the availability of the Online Institute in your newsletters and at your membership meetings and encourage operators to complete their CEU courses for the 2017 renewal cycle. Please publicize the availability of these online short courses: S Stormwater C S Utility Customer Relations I S Wastewater Collection C S Water Distribution Levels 2 and 3 The drinking water treatment plant operator Class B online course is now active and enrolling students. Also, don't forget to mention the Class C treatment plant operator courses. In closing, I invite each of you to become active in your association by attending your regional meetings and a board of directors meeting. Also, visit our website and tell us what’s on your mind, whether it be positive or negative. Tell us your training needs and what additional areas of training you would like to see our association offer. Remember that we are here to serve. S

Utilities s Invited to Host Locall “Drop Savers” Contest The Florida Section of the American Water Works Association will again sponsor th he statewide “Drop Savers” Water Conservation Poster Contest during National Drinking Water week, scheduled for May 7-13, 2017. Submission deadline is March 14, 2017, for local winners w to be submitted for judging at the state level, Florida utilities are encouraged to begin pre eparations for showcasing the creativity of their local children. The contest gives children from kindergarten through high school the opportunity to o design a poster about water conservation. Early in the year, local winners are chosen in five e diffferent f age groups, with winning entries advancing for statewide judging. Utilities publicize the local contests, distribute the contest material to local schools, coordinate the judging, recruit prize e sponsors, and arrange local award ceremonies. Although the state winners will be announced in mid-April prior to Drinking Water Week, utilities should start planning their local celebration now. Interested utilities may download the complete package of “Drop Savers 2017” start-up materials from the “Drop Savers” Florida Section S web . If you have questions or problems download site at www w.fsawwa.org/dropsavers . ding the materials, please contact state coordinator Melissa Ve elez at (561) 571-3750 or by email velezm@cdmsmith.com. Looking forward to seeing your utility represented this year! r!

Florida Water Resources Journal • February 2017

2016 FSAWWA AWARDS

To be presented at the FWRC Awards Luncheon Monday, April 24, 2017 | Palm Beach County Convention Center Outstanding Water Treatment Plant Award Class A, Class B, Class C, and Most Improved Deadline: March 17, 2017

Outstanding Water Treatment Plant Operator Award Deadline: March 17, 2017

AWWA Operatorâ&#x20AC;&#x2122;s Meritorious Service Award Deadline: March 17, 2017 For more information please go to our website www.fsawwa.org/WTPawards or contact Paul Kavanagh at (813) 264-3835 or kavanaghp@hillsboroughcounty.org

February 2017 â&#x20AC;˘ Florida Water Resources Journal

Florida Water Resources Journal â&#x20AC;¢ February 2017

Reducing Chlorine Costs and Improving Disinfectant Performance at a Water Reclamation Facility The “can and must-do” mindset of a motivated treatment plant operations team Dave Hoover and Bob Bigus

Photo 1. Shade cloth canopy

Photo 2. Floating cover component

Even with an appropriately designed domestic wastewater treatment facility, it is the responsibility of the plant operations team to determine the optimal operating parameters for each aspect of its processes. In some instances, there are plants where the staff simply relied on the suggested operating ranges that came with the design and are satisfied to meet their permit limits. In other instances, however, a motivated treatment plant operations team can find even better plant performance with further inhouse research and experimentation. With the sharply rising population in Florida, it is imperative to obtain the utmost performance each and every day from our treatment facilities, maintain costs at the most reasonable level, and achieve the most optimal efficiencies with any treatment chemical added, such as chlorine. Only then can the quality of our finished product be optimal. The research that was performed at our water reclamation facility (since we no longer waste our effluent, but in most cases, recycle it as a valuable irrigation product) can be defined as the “science” of our work, which is true at any treatment plant, for that matter. In its most general terms, science is defined as “bringing order out of chaos.” Our communities rely on the treatment plant operations team doing just that, with our diligent control and overall performance at these plants. Our teams have the ability to do this and it is something we all should pursue if we have a “can and must-do” mindset. This research work doesn’t always require an outside consultant. Ideally, if we only change one parameter at a time, and then fully evaluate what that change did for us, we can proceed in an orderly way to determine how we can further improve the quality of our final product. Creating, studying, and evaluating data tables then allows very objective conclusions to be made. As we refine operations, it truly is our job to quantify what each change does to the performance of that particular process in our treatment plant; however, if you change more than one variable at a time, it will be difficult (if not impossible) to determine which change brought any significant improvement.

Research in New Smyrna Beach with Floating Covers and Chlorine Performance

Photo 3. South chamber with floating cover

February 2017 • Florida Water Resources Journal

Recently, we went through the process of applying the scientific approach to the area of disinfection control. The Utilities Commission at the City of New Smyrna Beach operates a 7-mil-gal-per-day (mgd), Class A, water reclamation facility. The five-stage Bardenpho process produces 3.2 mgd of water, which is used by residential and commercial customers daily via 1500 reuse services. The commission’s wet weather discharge permit allows use of our outfall (after dechlorination) to the Indian River. This river is designated as an outstanding Florida waterway, and our plant performance must comply with everything necessary per the Florida Department of Environmental Protection (FDEP) operating permit limits and the 1991 Indian River Lagoon Act. Although our reuse utilization operation strategy has avoided river outfall for

over seven years, we continue to strive to maintain the lowest nutrient levels possible, in case river outfall is needed. How we disinfect our final product is critical to having a safe irrigation supply for public access reuse, and a river outfall that meets nutrient limits that is effectively dechlorinated and meets our disinfection byproduct limits is important as well. A sodium hypochlorite conversion project at our facility will begin shortly. This conversion from gaseous chlorine to liquid sodium hypochlorite will enable our facility to further ensure operator and community safety. We understand that maintaining effective disinfection in the chlorine contact chambers will be more costly, and perhaps, will triple our current expense for this treatment chemical, compared to using ton tanks. Although using bleach is significantly safer, it is more costly to use because of increased transportation costs associated with a product that is 85 percent water. A few years ago, we installed heavy shade cloth (photo 1) over our chlorine contact tanks. The goal was to decrease chlorine losses attributed to ultraviolet (UV) light, allow lowered chlorine feed to achieve the same residual, decrease the formation of disinfection byproducts (DBPs), and reduce annual costs for chlorine. The installation was successful based on a decrease in the total pounds of chlorine used to achieve the target residual, which was 3 parts per million (ppm), decreased monthly costs, and decreased DBPs, as expected. In view of another round of cost increases anticipated with the conversion to sodium hypochlorite (liquid bleach), we were compelled to revisit this area of performance in earnest. In researching other options for lowering costs of the disinfection process, information in trade magazines noted that some facilities were using newly developed floating covers in their chlorine contact basins. These

floats (photos 2 and 3) were first designed to reduce water loss due to evaporation in places such as California, where dwindling water supplies makes this a critical matter. It was also discovered that by using octagonal highdensity polyethylene (HDPE) floats that interlock naturally in a chlorine contact basin, less chlorine is lost to outgassing into the atmosphere, with almost complete shading from UV light. Sufficient quantities of floats were purchased and installed on one side of a chlorine contact tank (designed as a dual-chamber, side-by-side unit). Subsequent testing confirmed how effective these floats were in further improving disinfectant performance. Side-by-side chlorine comparison tests were performed in the north and south chlorine contact chambers to determine the efficiency of the new floating cover (placed in the south chamber) and, ultimately, to confirm if we would be justified in purchasing and installing a floating cover for the north chamber as well. We are also still using the original shade cloth canopy over the entire basin, which already provided some reduction in chlorine losses due to sunlight, as mentioned previously. This shade cloth was installed about eight years ago, subsequent to slightly exceeding disinfectant byproduct tests on effluent at that time.

The Data Evaluation In addition to the chlorine residuals testing, samples were sent to an outside laboratory for testing of total trihalomethanes (TTHMs), a category of DBPs. The chlorine performance is included in Table 1, and the disinfection byproducts data are in Table 2. Continued on page 30

Table 1. Chlorine Contact Chamber - Chlorine Residuals Test Data

Florida Water Resources Journal â&#x20AC;˘ February 2017

Continued from page 29 According to the results of the side-by-side chlorine testing, the chlorine loss in the north chamber (without floating cover, and only shade cloth used over this vessel) was 58 percent; the south chamber chlorine loss was 40 percent, under nearly identical conditions where the benefit of both the shade cloth plus the new floating cover was involved in the equation. This indicates that chlorine loss has been further reduced by 18 percent, a variance between the two basins that is significant. The analytical results from the outside laboratory indicated an 11 percent decrease in DBPs/TTHMs and other disinfection byproducts in the south chamber. Table 2. Disinfection Byproducts Comparison

Other benefits include the following: a. For the side in which we used the floating cover (south chamber), the loss of disinfectant strength was reduced between the entry point (where chlorine is added), and the end of the contact chamber. This is where we test the final product for confirmation that it complies with the minimum standard for public access reuse (1 ppm). It was shown by the test results that we have a stronger disinfectant residual leaving the plant with a product that is safer for public access reuse, compared to the side with no floating cover. b. Because we can feed less chlorine to achieve the same end point as we have now, there are noticeable treatment cost avoidances of this chemical (we spent approximately $40,000 last year). c. There is a tighter range of performance in disinfection levels (narrowed span of results), indicating finer control on this important process. d. Water temperature influences the effectiveness of chlorine disinfection. Increasing temperatures can decrease disinfection because the chlorine reacts quickly and breaks down. Water temperature data showed that the south chamber water cooled by 2°F (see Table 3). These results would have the effect of: • A decrease in chlorine doses • Less chlorine byproducts produced • Cleaner tanks and screens (less algae growth). A big plus for the operations team is reduced tank cleaning, since algae growth is greatly reduced by using the cover.

Conclusions The cost savings indicate that the price of buying these floats will be recovered in less than one year.

Table 3. North and South Chlorine Contact Chamber (CCC) Temperatures

Cost/Savings Calculations (for gaseous chlorine) A. Average chlorine demand = 350 lbs/day B. A 20 percent reduction in this demand = 70 lbs/day C. Cost saving attributed to floats = 70 lbs/day x 365 – approximately $4,810/year D. Cost of floats = $3,600 (i.e., cost recovery in <1 year) With the purchase of the second set, we will gain the full benefits. We will continue using the shade cloth, since it will reduce chances of the floats becoming airborne in storm winds, and the cost for the shade cloth is affordable. Finally, even though costs for chlorine will rise after this chlorine conversion, the amount of savings will also increase with the use of these hexagonal floats. This improvement will help the operations team contain this increase in operation and maintenance expenses for chemicals overall, and is an example of our proactive management strategy in action. The orderly effort that was utilized in this study helped our staff realize what these floats would do for us, from many perspectives, and how to quantify that for the records. It’s anticipated that our plant operations team will continue to apply this “can and must-do” mindset to future refinements, because they are indeed a truly motivated group.

Acknowledgments Thanks go to Derrick Densmore, lead operator, and the rest of the operations staff: Don Fisher, Joe Sciara, Leslie Wind, Dave Pogany, Mike Frazier, and George Moore; laboratory coordinator, Keith Suever; and Josh Tew, laboratory technician. Dave Hoover is director of the water and wastewater department and Bob Bigus is water reclamation facility supervisor for the Utilities Commission at New Smyrna Beach. S

February 2017 • Florida Water Resources Journal

Operators: Take the CEU Challenge! Members of the Florida Water and Pollution Control Association (FWPCOA) may earn continuing education units through the CEU Challenge! Answer the questions published on this page, based on the technical articles in this month’s issue. Circle the letter of each correct answer. There is only one correct answer to each question! Answer 80 percent of the questions on any article correctly to earn 0.1 CEU for your license. Retests are available. This month’s editorial theme is Alternative Sources for Water Supply. Look above each set of questions to see if it is for water operators (DW), distribution system operators (DS), or wastewater operators (WW). Mail the completed page (or a photocopy) to: Florida Environmental Professionals Training, P.O. Box 33119, Palm Beach Gardens, Fla. 33420-3119. Enclose $15 for each set of questions you choose to answer (make checks payable to FWPCOA). You MUST be an FWPCOA member before you can submit your answers!

Earn CEUs by answering questions from previous Journal issues! Contact FWPCOA at membership@fwpcoa.org or at 561-840-0340. Articles from past issues can be viewed on the Journal website, www.fwrj.com.

___________________________________ SUBSCRIBER NAME (please print)

Article 1 _________________________________ LICENSE NUMBER for Which CEUs Should Be Awarded

Article 2 _________________________________ LICENSE NUMBER for Which CEUs Should Be Awarded

If paying by credit card,fax to (561) 625-4858 providing the following information:

___________________________________ (Credit Card Number)

____________________________________ (Expiration Date)

Water Quality and Supply Issues? There’s a Wetland for That! Chris Keller

(Article 1: CEU = 0.1 WW)

1. In Florida, the use of natural wetlands for effluent polishing and disposal is regulated under chapter ___________, Florida Administrative Code. a. 62-600 b. 62-602 c. 62- 611 d. 62-620 2. For the period 1988 through 2015, outflow total phosphorus concentrations from the Orlando Easterly Wetlands site a. were reduced by 15.7 mg/l. b. averaged 1.9 mg/l. c. averaged 0.06 mg/l. d. peaked at 0.23 mg/l. 3. By providing treatment and disposal in the same project footprint _____________ wetland systems replenish aquifer levels with high-quality water. a. rapid infiltration b. groundwater recharge c. slow rate infiltration d. percolation pond 4. The ______________ is one of few large-scale municipal wastewater treatment wetlands in the U.S. within which sediments and vegetation have been removed to improve hydraulic efficiency. a. Orlando Easterly Wetlands system b. PurEnergy site c. Everglades Agricultural Area d. Ichetucknee Springshed 5. Which of the following dominant wetland pollutant removal mechanisms is effective for all water quality parameters listed in this article? a. Sedimentation b. Ultraviolet photolysis c. Volatilization d. Adsorption

Aquifer Storage and Recovery System Enhancement Through Reduced Operating and Capital Costs Jeffrey Poteet, Bruce Weinstein, and John Mayhut (Article 2: CEU = 0.1 DW/DS)

1. Prior to aquifer storage and recovery (ASR) injection, pH is reduced from 7.5 to 7 by dosing with a. sulfuric acid. b. hydrochloric acid. c. corrosion inhibitor. d. carbon dioxide gas. 2. The authors theorize that after three injection cycles, arsenic reduces to nondetect concentration because a. dissolved oxygen is removed from water prior to injection. b. oxygen is consumed in reaction with organic compounds. c. all arsenic is rinsed from the geological formation. d. formation arsenic is fixed in place by biological interaction. 3. To decrease annual operating costs, the utility converted from ______________ for monochloramine production. a. liquid chlorine to hypochlorite b. hypochlorite to liquid chlorine c. ammonium sulfate to gas ammonia d. gas ammonia to ammonium sulfate 4. Chloride content of water stored in the ASR system is approximately ____ parts per million (ppm). a. 6 - 15 b. 150 - 180 c. 730 - 780 d. 2900 - 4000 5. Which of the following is listed as a benefit of having the ASR wellfield available as a third water supply? a. Allows existing Marco Island wellfields to be abandoned b. Replaces reclaimed water entirely as an irrigation source c. Allows regulatory exemption from South Florida Water Management District water use restrictions d. Provides high-level disinfected wastewater effluent disposal alternative Florida Water Resources Journal • February 2017

FWRJ READER PROFILE

Mike Darrow Mulberry, Florida Work title and years of service. I am currently between jobs and looking for employment. I was most recently deputy director of public works for the City of Temple Terrace. I have 32 years of service in the water and wastewater industry, including working in operation and maintenance management, groundwater and surface water treatment in Florida and Illinois, surface water treatment on Lake Michigan for Lake County, Ill., and wastewater collection and water distribution systems management. What does your job entail? In my last job I directed utility operations and maintenance and managed the entire water and wastewater departments, or as I like to say, I was a “small business manager” working in all phases of business operation in a 24/7 capacity: operations, maintenance, environmental compliance, employee allocations and relations, engineering management of capital improvement projects, budgeting and planning, customer service relations, and problem solving. I worked with a great staff that helped keep our potable water safe, exceeded all environmental regulations, and continuously kept our wastewater flowing (pumping) to treatment without spills or customer complaints. All of this was done while being underbudgeted and understaffed, which is the new

world we work in. This is where the “small business manager” comes in; it takes a lot of face time (meetings), review, and planning to keep your utility in compliance with regulations and permits, and also on track with customer service expectations. Probably the most important thing you can do to be successful is to be a public servant who really cares about your customers and how to respond and relate to them. Education/training you’ve taken. My education in water operation and maintenance started from day one by taking classes at night and receiving on-the-job training during the day to hone my professional skills. It all started with getting my hands dirty, I believe, by means of such things as water/sewer leaks and repair, meters, calibrations, instrumentation, and working with water/wastewater equipment and components. This is the foundation for a base of knowledge; you have to have a strong foundation to build on, you know! I have a bachelor’s degree in business economics from Eastern Illinois University. While I was working I also received an associate in applied science degree in environmental engineering from the College of Lake County, specializing in water and wastewater technologies and management. I’ve taken a ton of classes from FWPCOA and AWWA in my career. I truly enjoy learning and try to learn something new every day. These organizations have excellent continuing education unit and certificate training. What do you like best about your job? I really enjoy working with people, both employee professionals and our customers. I enjoy problem-solving to address customer service issues. These are always like solving a

Mike with a catch at Lake Lulu in Winter Haven.

February 2017 • Florida Water Resources Journal

unique and complex puzzle: dive into the facts, do the research, and go the extra mile for good rapport with your customers. I love working in the water and wastewater profession. I have met so many hard-working operators and technicians over the years, and it's great to learn from them as well. What professional organizations do you belong to? I belong to FWPCOA and FSAWWA; both are excellent organizations. I’m currently vice president of the state board for FWPCOA. “Operators helping operators” is their motto. I’ve been a volunteer in the organization for the last eight years in Region 10, and to now be elected to the state board is truly an honor. There is a lot to be learned from the folks involved in our association as they have diverse knowledge and backgrounds. It’s great to network with the professionals in our industry; knowledge is passed from one to another, and this is what the operator’s association does best. How have the organizations helped your career? Besides all the excellent training, FWPCOA, FSAWWA, and FWEA have come together from their different professional disciplines to make our industry more productive and responsible to the public. One way they do that is by helping to jointly produce this magazine, which is a premier publication for the industry nationally. It’s great that it’s included in your membership. I have continued to learn from the countless articles, columns, and studies in the magazine. This has helped me when I’m reviewing and applying ideas to various areas of my work. What do you like best about the industry? What I like best is serving the public. We work with a resource that is needed for a good quality of life. Together, we all work as part of a team, to meet the needs of our customers, now and in the future. The role we play is often behind the scenes and mostly unnoticed, but our efforts are felt every day. I like working behind the scenes to preserve and deliver our precious resource for the public. What do you do when you’re not working? I enjoy spending time on the water fishing and spending time with my family. I guess water is always something I like to be around and I enjoy kayaking with my wife. I also like volunteering to help folks where I can: at my church with high school youth, and I am currently serving on the Water and Soil Conservation Board for Polk County, promoting good stewardship. S

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F W R J

Who Needs Pretreatment? Not Orange County Utilities’ Operational Aquifer Storage and Recovery Mary Fickert Thomas, Kim Kunihiro, Kathy Traexler, and Mark Johnston rsenic is an element found naturally in the limestone aquifers that underlie Florida. The introduction, or recharge, of a water containing a higher dissolved oxygen (DO) concentration than the native groundwater causes a chemical reaction that results in the release of soluble arsenic into the groundwater. In 2001, with the passage of the Chemical Contaminants Rule, the U.S. Environmental Protection Agency (EPA) lowered the arsenic maximum contaminant level (MCL) from 50 parts per billion (ppb) to 10 ppb, and aquifer storage and recovery (ASR) permits were slowed to a near halt. With a historic MCL of 50 ppb, a number of operational permits were issued for ASR systems that could successfully reduce concentrations below this limit; however, the significantly lower MCL of 10 ppb meant that far fewer ASR well systems could comply, so many who wished to utilize ASR as a water storage option sought out pretreatment options to lower the DO concentrations, thereby reducing the potential for arsenic mobilization. Though some pretreatment systems proved successful, many remained riddled with challenging maintenance issues and significant cost.

Orange County Utilities (OCU) pursued an alternative to DO pretreatment with its potable water ASR well system. By injecting a “buffer” water volume, far in excess of its storage volume, OCU created a physical barrier between the stored water and the arsenic-containing limestone aquifer. Through a number of successive cycle tests, OCU conditioned the aquifer with the introduction of oxygen-rich water. Using several operational techniques, OCU was able to steadily reduce arsenic concentrations in the recovered water until the concentrations were consistently below the 10 ppb MCL for two consecutive cycle tests.

Technique One: Extensive Aquifer Conditioning During the course of OCU’s cycle testing program, a number of cycle test patterns were attempted. Initial cycle tests were large in volume and long in duration. This was done to maximize the storage zone and the buffer between the native limestone aquifer and non-native recharge water. It was thought that by pushing the storage zone to

Figure 1. Arsenic Concentration in the Nearby Monitor Well

February 2017 • Florida Water Resources Journal

Mary Fickert Thomas, P.E., is supervising engineer and Mark Johnson is senior environmental engineer with WSP|Parsons Brinckerhoff in Orlando. Kim Kunihiro is water quality and water production manager and Kathy Traexler, P.E., is senior engineer with Orlando County Utilities.

the higher end of its capacity, the interaction between the arsenic-containing formation and the oxygen-rich water would occur at a farther distance from the ASR well, and therefore have a lesser impact on the water quality sampled from the ASR well. While that concept did not occur quite the way it was intended, there was another consequence that would later be realized as beneficial: the aquifer was being conditioned. Initial cycle tests at the onset of the cycle testing program caused a significant imbalance in aquifer water chemistry. A precycle test buffer of approximately 180 mil gal (MG) was injected to act as a barrier between the formation and the ASR storage zone, but this volume was never recovered. The first cycle test involved the injection of approximately 30 MG, for a total injected volume of 210 MG. Treated potable water contains a relatively high level of DO (on the order of 5 to 6 mg/L). The introduction of this water to the native aquifer with nearly no DO resulted in the release of a significant amount of arsenic from the aquifer formation, and an arsenic concentration of over 140 ppb (Figure 1). This recharge water was subsequently recovered and never reinjected, removing the leached arsenic from the system. The second cycle test, which resulted in a slightly larger storage zone of approximately 285 MG, continued to expand the storage zone and resulted in additional leaching of arsenic from the limestone aquifer; however, with only a slight increase in the storage zone of approximately 93 ft, or 16 percent of the first cycle test radius, the arsenic concentration was not nearly as high, with concentrations at less than half of that seen in the first cycle test.

Upon reviewing the water quality data, the third cycle test appeared to have had the most perceptible impact on the aquifer conditioning. By pushing approximately 525 MG of potable water to a storage zone radius of 893 ft, the greatest amount of the formation that would ever be exposed to oxygen-rich water was exposed and “scrubbed” of leachable arsenic. Once again, all of the water from this cycle test was removed and never reinjected, leaving the aquifer free of the newly introduced arsenic. All subsequent cycle tests were smaller than the third. By remaining within that maximum radius, oxygen-rich water was never exposed to portions of the formation, which had not already been “scrubbed” of the leachable arsenic. While some arsenic remained in the aquifer, cycle tests four and five exhibited significantly reduced arsenic, with cycle tests six and seven meeting the MCL for arsenic in drinking water.

Figure 2. Typical Monthly Central Florida Rainfall

Technique Two: Mimic Seasonal Conditions The functionality of a fully operational ASR system is similar to that of any other storage facility: the storage zone is recharged, or “filled,” during periods of excess rainfall when the additional water is available and then recovered when water demands increase during drier periods. This approach of recharge and recovery attempts to mimic naturally occurring seasonal weather patterns. In central Florida, the wet season is generally late May to mid-October (Figure 2), which means that, at some point following the beginning of the wet season, an ASR well is filled, or recharged, over the course of a number of months. After a period of time, or some desired well volume, the well is placed into a storage phase until there is a demand for the stored water, and it is then withdrawn. The goal of the cycle testing program was to demonstrate that all water quality requirements could be met under practical operating conditions. Since precipitation in the state varies, it was important to test a variety of cycle-testing scenarios. Initial cycle tests involved the injection of water at somewhat higher flow rates and relatively short storage periods, on the order of 40 to 60 days. Because the aquifer was still being conditioned and the aquifer chemistry was unstable, there was a significant increase in arsenic concentrations in the native water, even when storage periods were somewhat short. With time, storage periods were extended, with the longest occurring during the fifth test cycle. With storage ultimately lasting nearly one year due to mechanical issues at the well, chemical reactions were allowed to occur for a longer duration, resulting in a gradual increase in the arsenic concentration. Though still at the lowest peak levels observed for a cycle test to date, it can be seen in

Figure 3. Dissolved Oxygen Concentrations in the Nearby Monitor Well

Figure 1 that as the storage period advanced, so did the arsenic concentration. Cycle tests six and seven were both shorter in duration, and this is thought to have been another factor in the lower levels of arsenic observed in the sampling wells.

Technique Three: Minimize Agitation With Injection Rate Management The pump used to recharge the ASR well was sized at approximately 3 mil gal per day (mgd), but averaged an injection rate of approximately 2.5 mgd in early 2010. Cycle tests one through five were all operated at a rate of between 2 and 2.5 mgd. During these cycle tests, DO levels were extremely varied, with a range of 1 to 6.4 mg/L during the injection of the buffer volume and 0.5 to 6 mg/L during the fifth cycle test (Figure 3). With the goal of reducing agitation in the aquifer from the injection of the higher DO water, the injection rate was lowered to approximately 1.7 mgd for cycle tests six and seven. It was hypothesized that by reducing agitation in

the well, mixing in the aquifer would be reduced, as would the potential for high-DO water to reach portions of the formation where arsenic could be released (Figure 3); this resulted in some success. While the DO sampled from the nearby monitor well was not reduced significantly, the variation in maximum and minimum concentrations were narrowed in cycle tests six and seven, as compared with previous cycle tests.

Technique Four: Extensive Water Quality Monitoring One of the greatest tools in determining what impact the treated potable water had on the native aquifer system is an extensive water quality monitoring program. While not all parameters analyzed showed much value in the determination of aquifer performance, and while testing samples for a long list of parameters for a long period of time—in this case, over 6 years— is quite costly, much of the data proved to be Continued on page 36

Florida Water Resources Journal • February 2017

Continued from page 35 valuable in determining what operational changes might improve ASR water quality. For OCU’s ASR well, water quality sampling results were utilized to develop a better understanding of the extent of the ASR storage zone. In order to achieve this, an analyte that exists in the potable water supply, but not in the native aquifer, needed to be observed in the aquifer. For OCU’s ASR well, fluoride was used as the tracer analyte and is added to OCU’s potable water supply to a concentration of approximately 0.6-0.7 mg/L, as it does not exist naturally in the groundwater. Fluoride is also stable in the environment and does

not degrade or convert to another analyte. As Figure 4 shows, fluoride concentrations in the far well reached concentrations of 0.6 mg/L and above in the third cycle test, indicating that the storage zone edge had indeed reached the far monitor well, 510 ft away from the ASR injection well; however, at no point during any cycle test did arsenic in the far well reach the 10-ppb MCL, as shown in Figure 5. In addition, fluoride concentrations in the well increased and decreased consistently with ASR recharge and recovery, indicating that the storage zone remained somewhat well-defined during cycle testing. Information of this type is invaluable to understanding the performance of

Figure 4. Fluoride Concentrations in the Far Monitor Well

the ASR well and would not be possible without extensive water quality monitoring.

Summary and Conclusions The passage of the Chemical Contaminants Rule by EPA resulted in a decrease in the arsenic MCL from 50 ppb to 10 ppb and made it far more difficult for those applying for an ASR operational permit to obtain one. Pretreatment systems are implemented by many applicants hoping to minimize the occurrence of arsenic exceedances by removing the DO from the injectate that causes the arsenic leaching in the first place; however, these pretreatment systems can be expensive and are often riddled with ongoing and cumbersome maintenance issues. The OCU pursued an alternative to DO pretreatment with its potable ASR well system and ultimately obtained an operational permit by utilizing the following techniques: S Technique One: Extensive Aquifer Conditioning - The native limestone aquifer was exposed with DO-rich potable water during early cycle test phases. The stored water, with high levels of arsenic, was removed from the aquifer. By implementing this conditioning approach during early cycle tests, subsequent, smaller cycle tests revealed significantly lowered arsenic levels. S Technique Two: Mimic Seasonal Conditions - By keeping storage periods relatively short to demonstrate variability in precipitation, OCU reduced the potential for additional migration of the storage zone and, therefore, the potential for additional arsenic leaching chemical reactions. S Technique Three: Minimize Agitation with Injection Rate Management - It is possible that lowering the injection rate resulted in less agitation in the aquifer, thereby lowering the potential for mixing and chemical reactions between high-DO recharge water and the native aquifer. S Technique Four: Extensive Water Quality Monitoring - Tracking certain water quality parameters frequently and over extended periods can give meaningful insight into aquifer behavior. While these techniques require extensive monitoring and evaluation, they can result in a more cost-effective ASR well operation.

References

Figure 5. Arsenic Concentrations in the Far Monitor Well

February 2017 • Florida Water Resources Journal

• Orange County Utilities, “Operational Permit Application and Supporting Documentation, OCU Eastern Potable ASR Project.” December, 2015. S

Test Yourself

A Refresher on pH and Alkalinity 1. Which of the following is the best definition of alkalinity? a. The ability of a liquid to neutralize an acid. b. The total amount of alkaline substances in the liquid. c. The total amount of acidic substances in the liquid. d. The exact amount of dilute sulfuric acid needed to raise the pH to 4.5.

Ron Trygar

2. A pH reading of 4 is how many times more acidic than a pH of 7? a. Three times c. 30 times

Send Us Your Questions Readers are welcome to submit questions or exercises on water or wastewater treatment plant operations for publication in Test Yourself. Send your question (with the answer) or your exercise (with the solution) by email to: rtrygar@treeo.ufl.edu or by mail to: Ron Trygar, CET Senior Training Specialist UF TREEO Center Gainesville, Fla. 32608

a. Denitrification is occurring. b. Nitrification is occurring. c. Carbonaceous biochemical oxygen demand (CBOD) is being oxidized. d. The tank is anoxic.

0.1 parts acid to one part alkalinity 0.4 parts acid to one part alkalinity 0.8 parts acid to one part alkalinity 1 part acid to one part alkalinity

5. How many milligrams (mg) of alkalinity are reduced for each milligram of ammonium oxidized to nitrate in the biological nitrogen removal process? b. 3.5 mg d. 10.5 mg

6. pH is measured on a scale of a. 4, 7, and 10. c. 0 - 14.

b. 4 - 20. d. 0 - 100.

b. 5.1 mg/L d. 260 mg/L

8. Fresh domestic wastewater from a combined residential and commercial collection system will normally contain how much alkalinity? Less than 50 mg/L as CaCO3 100 mg/L as CaCO3 10,000 mg/L as CaCO3 The characteristics of the potable water supply influences alkalinity.

9. In the coagulation-flocculation process of surface water treatment using aluminum sulfate (alum) as the primary coagulant, lime addition may also be required. What is the purpose of lime addition? a. Lime helps raise the pH to enhance softening of the hard source water. b. Alum will not work without the addition of lime. c. Lime prevents additional sludge from forming in the sedimentation tank. d. Lime supplements the water alkalinity and aids in complete precipitation of alum.

4. What is the volatile acid to alkalinity (VA:Alk) ratio of a properly operating anaerobic digester?

a. 1.1 mg c. 7.1 mg

a. 2.5 mg/L c. 25.9 mg/L

a. b. c. d.

b. 10 times d. 1,000 times

3. A reduction of alkalinity from the inlet end of an aeration tank to the outlet end of the tank likely indicates what?

a. b. c. d.

7. How many milligrams per liter (mg/L) of alkalinity will be consumed during complete nitrification if the influent wastewater contains 36.5 mg/L of ammonia? Select the closest answer.

10. The operator of an aerobic digester notices excessive foaming on the surface of the tank, dissolved oxygen readings over 3 mg/L and a liquid pH of 5.3, and the concrete walls of the tank show signs of deterioration and concrete crumbling. What is most likely cause of these conditions? a. Underaeration causing denitrification b. Overaeration causing nitrification c. Excessive waste sludge flow causing short-circuiting d. Anaerobic conditions causing an unbalanced volatile acid-to-alkalinity ratio Answers on page 62

Florida Water Resources Journal â&#x20AC;˘ February 2017

FSAWWA SPEAKING OUT

Our Future Water Professionals Grace Johns Chair, FSAWWA

he most important component of FSAWWA’s goal to advance knowledge creation and exchange is to recruit and prepare our future workforce of water professionals. According to AWWA’s 2016 State of the Water Industry report, it seems to be difficult for the water industry to recruit, train, and retain skilled employees. Utilities will be further challenged as a large number of water industry employees are nearing or are currently eligible for retirement. A significant amount of institutional knowledge could be lost without proper succession planning and process documentation. The results of the report’s survey of AWWA members found that 44 percent of the 1,468 respondents have a negative perception of the water industry’s preparation for talent attraction and retention. This is, however, an improvement over the 54 percent who responded that way in 2015. Just 1 percent of respondents indicated that the water industry was fully prepared to cope with any expected

retirements in the next five years, while 12 percent thought the industry is not at all prepared and 32 percent thought it was only slightly prepared. It’s recognized by AWWA that investing in students and young professionals is critical for the future of the water profession. We can no longer just talk about what we are going to do—we need to do it.

Contests We began this journey over 25 years ago when we first sponsored the annual statewide “Drop Savers” Water Conservation Poster Contest during National Drinking Water Week. The contest promotes water awareness and the importance of water conservation by providing students in kindergarten through high school the opportunity to design a poster about water conservation. First-, second-, and third-place winners in each of five gradebased divisions receive recognition and prizes. In 2016, 26 water utilities throughout Florida participated and over 100 posters were submitted for the statewide competition. Our other big student activity is the annual Model Water Tower Competition (MWTC), which introduces middle and high school students to the world of engineering and the water profession by requiring them to design and build a water tower with specific

2016 Drop Savers Division 5 (High School) First-Place Winner: Cameron Mack, Orange County Water Utilities Division.

February 2017 • Florida Water Resources Journal

size and height requirements. The FSAWWA’s Region X (West Central Florida) was the first to inaugurate this contest back in 2004 under the leadership of Tod Phinney and the Region X Youth Education Committee. In 2016, eight of our 12 regions held MWTC events that were attended by over 850 students. Middle school and high school teachers at the participating schools within the region present the MWTC to their classrooms, distribute the student packets, and collect and return the student registration forms to the FSAWWA region. The region administers a fun-filled day where students from all participating schools in that region enter their water towers to be judged in four categories: cost efficiency, hydraulic efficiency, structural efficiency, and design ingenuity. In 2010, FSAWWA received the AWWA Section Education Award in recognition of our MWTC. This award recognizes section initiatives that educate water industry personnel, the public, students, or other groups about drinking water, and disseminates guidelines to enable other AWWA sections to conduct comparable educational activities.

Funding and Support Since 2013, FSAWWA has provided funding and utility support as a proud partner of Heritage High School’s Academy of Environ-

Over 200 students attended the 2016 Model Water Tower Competition in FSAWWA Region III (Central Florida) held at the University of Central Florida.

mental Water Technology in Palm Bay. Among the water resource technology and environmental science courses offered, certification classes in drinking water and wastewater operations are available, with the opportunity to graduate with both certifications. Since 2010, the Academy has enrolled 139 students, and 111 of them have graduated. Of these, 68 high school seniors have taken the Florida Department of Environmental Protection (FDEP) Class C drinking water treatment plant operator exam, and 25 of them passed the exam. Five now hold positions in the drinking water industry as drinking water treatment plant operator trainees: four at the City of Melbourne and one at the City of Palm Bay. The section recently approved a threeyear funding and collaboration partnership with the St. Johns Technical High School’s Academy of Coastal and Water Resources in St. Augustine. The academy was first established during the 2012-13 school year and promotes the graduation of students who are knowledgeable, skilled, and proficient in water and wastewater treatment and distribution. Students are required to master rigorous and relevant performance standards, experience multiple hands-on field experiences, conduct real-time research, and complete internships. Students are currently leaving the academy prepared to take the FDEP operator certification program Level C license exam. The academy began with 20 students, and currently, 26 students are enrolled.

The section’s new statewide Model Water Tower Competition logo.

Scholarships The FSAWWA has a long history of providing scholarships to promote the training and education of Florida water professionals. Each year, the Roy Likins Scholarship Committee awards scholarships to Florida undergraduate and graduate students. The minimum scholarship amount is $2,500 per student and provides reimbursement for tuition, books, and fees through the college or university during a twoyear period. In 2016, the committee awarded $32,500 to eight Florida students.

Erica LaBerge of FSAWWA Region III (Central Florida) checks the water tower’s dimensions prior to the structural test.

The Operators and Maintenance Council provides up to four scholarships of $500 per eligible student each year to upgrade the student’s drinking water or distribution system operator license. Up to two scholarships of $1,000 per eligible student pursuing a college degree relating to the drinking water industry are also available each year. In 2016, the council awarded $2,000 in scholarships. I hope you now have a better idea of what FSAWWA is doing to recruit and prepare our future work force. The section is very proud of these programs and continues to seek and evaluate new ways to expand its influence in recruiting and training future water professionals. We need to do much more to reach out to our youth and those wishing to switch careers and give them the knowledge and resources they need to step into water utility careers as quickly as possible. This effort requires FSAWWA volunteers to evaluate, design, and implement effective programs and partnerships. If you want to help, please contact FSAWWA staff, or reach out to our Public Affairs Council chair, Scott Richards; our Operators and Maintenance Council chair, Andrew Greenbaum, or the council’s past chair and current trustee, Steve Soltau; or your region chair. All contact information is available at www.fsawwa.org. Many ideas are currently being proposed and discussed, and many opportunities exist to facilitate careers in the water industry that will help to make a better world through better water. S

Academy of Environmental Water Technology graduates Connor Morgan and Bella Gonzalez work full time as drinking water operators at the City of Melbourne Water Treatment Plant.

Florida Water Resources Journal • February 2017

PROCESS PAGE Greetings from the FWEA Wastewater Process Committee! This column highlights the City of Plant City Advanced Wastewater Treatment Plant, which won honorable mention for the Earle B. Phelps Award in the category of advanced wastewater treatment facility in 2016.

City of Plant City Advanced Wastewater Treatment Plant Tim Ware mong the strawberry fields and cow pastures of rural Plant City, you may be surprised to find an award-winning advanced wastewater treatment plant. In a town known locally and nationally for its annual Strawberry Festival, which brings many visitors, including country recording artists and dignitaries, from around the world, the city also operates a progressive utility dedicated to preserving the natural environment. The earliest recorded sanitary sewage facility in Plant City dates to 1913. By 1929, the collection system had expanded to include over 14 mi of sewer lines. In 1951 the Imhoff tanks and septic tanks were replaced with a 1.5 mil gal per day (mgd) trickling filter process. In 1968 the city began design to extend the collection system to collect more of the residential, commercial, and industrial wastewater; design of a new 4-mgd activated sludge plant wastewater treatment plant using the extended

aeration process also began at that time. The current plant was completed and started in 2008 and is designed to treat 10 mgd, with a peak of 22.5. Operations at the plant consist of: a headworks structure, including a mechanically cleaned fine bar screen, a backup manual bar screen, a Pista grit removal system, and a Parshall flume for measurement system, with an odor control system. A master pumping station with six pumps lifts the water to an anoxic tank subdivided into three parallel trains with a total volume of 376,000 gal, which is followed by three oxidation ditches with a combined volume of approximately 12.5 mil gal (MG). Flow is then split between three final clarifiers, providing a combined volume of approximately 5.25 MG. There is a reject storage system, including three concrete basins of 2.5 MG and one 15-acre pond with a total capacity of 29 MG. After clarification, there are thirteen Parkson continuous backwash upflow filter cells with a combined surface area of 3,250 ft2, followed by a fourchannel chlorine contact chamber with a total volume of 332,000 gal. Finished water is stored in one of three reclaimed water ground storage tanks with a combined capacity of 12 MG and distributed to the reclaimed system by a highservice pumping station. All disinfection is accomplished using liquid chlorination. The solids treatment consists of four aerobic digesters with a combined capacity of 2.8 MG, and two belt filter presses with a capacity of 2,000 pounds of dry residual per hour. The stabilized residuals are land applied.

February 2017 â&#x20AC;˘ Florida Water Resources Journal

A unique feature of the facility is the plant staff. Water and wastewater operations are run from the same control room at the treatment plant. As a result, most of the facility staff is duallicensed in both water and wastewater through the Florida Department of Environmental Protection. This facility has been the recipient of numerous awards since coming online in 2008. Some of these include: S Earle B. Phelps: First place in 2012 and 2015, runner-up in 2013 and 2014, and honorable mention in 2016 from the Florida Water Environment Association. S 2014 outstanding facility award from the Florida Water and Pollution Control Operators Association. S 2009-2010 water resource project of the year presented by the Florida Chapter, West Coast Branch of the American Public Works Association. Tim Ware, P.E., is client manager with Arcadis in Tampa. S

SPOTLIGHT ON SAFETY

Hazard Identification Consequences of Visual Disparity Doug Prentiss Sr.

he single most important part of accident prevention is identification of the actual hazard to be faced. The recognition of the need to identify hazards is actually the foundation of many safety standards. The Occupational Safety and Health Administration requires employers to perform hazard identification as the basis for the selection of personal protective equipment. Generally, the gold standard for this issue is seeing the hazard itself, but what you see is actually the result of several activities that create a picture in your mind’s eye that you react to. Your mind plays a powerful role in what you see, and if your mind is predisposed to see something, it may initially give you incorrect information. This confusion between your eyes and brain is real and is reflected in many ways. When people see something, rubs their eyes, and then look again, they’re experiencing a conflict between their eyes and brain. You hear comments from people who say, “I couldn’t believe my eyes.” Hopefully, it was just too good to be true, but that is not always the case. A person has a preconceived idea of what will happen or what will be seen, and when the picture in the mind does not match what is actually seen, he or she will question the results, and in many cases, look a second time or delay any action. Many auto accidents have a component where one person did not see the other person. We call it a “blind spot” sometimes, but the reality is that the car, motorcycle, or other vehicle was there—it simply was not seen in time to prevent the accident. Accidents happen fast (too fast in some cases) to contemplate, consider, or even react to. In the water and wastewater industry, some of our most dangerous hazards are invisible, and by the time you can see them, it’s too late. Lock out/tag out standards require us to identify stored energy, which may pose a hazard to workers who could be injured by an unexpected release of that energy, but they have to be able to recognize it to be able to prevent its release and their injury.

Many times, visual recognition starts with a shape, color, or even a movement, but change is something we all look for to identify unsafe situations. We usually hope nothing has changed, but something as simple as a stick on a walkway may give an operator a simple visual outline of a snake and compel the operator to hesitate and look closer, or take an alternate path until the picture becomes clearer. The other side of the story is the same stick can cause the operator to take a wrong step because of a reaction that was too quick. For most people change is a reason to pay closer attention and is usually associated with an increased level of apprehension. This apprehension or fear compels people to look closer, move more carefully, and be more prepared to take aggressive action to defend themselves or prevent them from being injured. The recognition that something has changed is an important part of accident prevention for workers. Public safety workers, such as police officers, struggle with these same issues, but their decisions can result in more than just their injury, if incorrect. Each of us, as a human being, will react differently when we are scared or afraid, and we see this all too often result in an unintended consequence for all involved. The recent videos of human tragedy during law enforcement activities seem to show what happened at the moment—captured on film—but so many other influences contribute to an incident that are deep within each of the individuals involved throughout their lives. It is those hidden prejudices that contributed to a bad outcome for both. The lessons being learned by law enforcement toward community policing and diversity training should not be ignored by our industry. Diversity training is not to get one race to accept another; it’s to recognize that all people have value. So yes, even personal experiences, prejudices, and basic lack of understanding can contribute to an accident.

The Importance of Training Training is critical to understand the nuts and bolts of equipment to prevent work-related injuries. Understanding what the equipment is for and how it performs helps a worker to understand what dangers it may pose. Understanding how to control those hazards can

February 2017 • Florida Water Resources Journal

prevent injuries to the workers who perform maintenance and operate the equipment. Distance learning assumes no prejudice. Some online training does provide prerequisites, but it cannot incorporate personal experiences. Many workers really believe that doing something at work just as they would do it for themselves at home is their gold standard. Then, we have the invisible hazards such as toxic, flammable, and oxygen-deficient atmospheres that don’t really care about who you are or what you think. So, distance learning does have an important place in accident prevention—but we need more. Technical hands-on training is what is needed for our workforce, including facilitated discussion with knowledgeable individuals who have done the work and understand the details, the background, and what the real hazards are. The best-skilled operator or maintenance person in the world, with all the licenses and certifications, still needs to be shown around a new plant to understand the unique hazards associated with that workplace. The Florida Department of Environmental Protection and its training advisory committee do a wonderful job of making sure that every licensed operator understands at least something about every type of process used in our state, but that does not provide the level of detail needed to actually run a plant. Knowledge-based training—in whatever form—is a great baseline, but each organization needs to provide on-the-job training for the specific hazards at that plant. We have numerous plants built in our state that were designed by the same engineers, but somehow, they are all run just a little different. Our plants are treating different water with different collection and distribution systems, and so an identical plant may have wide-ranging hazards based on how the water has to be treated.

Influencing Legislation In 2000 then-Gov. Jeb Bush wrote the division of safety out of the budget. He did it against the recommendations of the boards that had been selected to review the issue. All reports identified the state’s division of safety as being cost-neutral as it was paid for out of the division of workers compensation and was not a line item in the general budget. The problem was not money—it was an inconvenience to big business in Florida. Big business argued that it was unnecessary since

lost-time worker compensation rates were lower in 2000 than they had been in 10 years. They also argued that the division of safety had never actually fined anybody, and in fact, no fines were ever collected by the state, so in their minds it wasn’t helping anybody. When I had white powder coming out of old walls, they would provide help and come out and test it for me to see if it was asbestos. If someone needed training on lockout, the state had basic programs that they would provide to help businesses develop their own programs. In 1999 I attended the last governor’s conference in Tallahassee, where all of us who struggled to ensure worker and public safety got to get together to talk, exchange ideas, and learn what could be done to make things as safe as they can be in a dangerous world. Since 2000, when government managers were told safety is gone, many smart cities have increased their work to prevent injuries. Almost every city, county, or governmental agency has a risk management division that struggles to keep people well-trained and safe. My son, who works for the City of Gainesville,

recently held a year-end safety program where the results of the year are presented and goals for the coming year are discussed by each group. Activities to encourage workers to participate are included and safety is identified as something of value for the organization. There are so many ways of establishing that safety should be valued and a part of every person’s job, and establishing safety as an important behavioral requirement for every worker is a management responsibility. Not having a resource such as the old state safety division has created a void where only the larger organizations can afford to do the training we all know is needed. Gainesville, Tallahassee, Broward County, Miami Dade, and others can afford to have dedicated staff, but the larger organizations are the exception. The fact is that most smaller organizations in our state do not have dedicated safety and training staff. Gov. Rick Scott believes in the value of training to reestablish safety training assistance for government agencies here in Florida. The government could provide a tremendous level of online assistance, sample programs, references,

guides, and many other services that could help small agencies to develop basic safety programs that could assist front-line supervisors. Advance training for team building and diversity provide significant benefits for workers that small organizations need, but many cannot afford. Since the division of workers compensation would benefit from reduced accidents, perhaps a department of safety resources could be established. In addition, each year a centralized meeting similar to the old governor’s conference could disseminate the latest and best information. Simply having this as an item that is directly supported by our governor sends a clear message to city managers and administrators that is still needed. Providing the necessary resources to all of us who are in the public safety business to ensure safe workers, protect the public, and prevent unnecessary costs simply makes sense. Doug Prentiss Sr. is a member of the FWEA Safety Committee. S

New Products The STAR ONE nonclog pump from Smith & Loveless increases pump efficiency anywhere from 3 to 5 percent higher than previous pump models. It has an oversized, stainless steel shaft that minimizes overhang, reducing shaft deflection and improving pump efficiencies. This is achieved through minimal pump heights and rigid construction. Shaft end play is limited to bearing shake and shaft runout is limited to 0.003 in. Close tolerances are tighter than even NEMA specifications. The impeller is designed for maximum efficiency by trimming the impellers inside the shrouds, leaving the back shroud full-diameter to prevent stringy material from winding around the shaft and reducing efficiencies. (www.smithandloveless.com)

Culligan International introduces its new industrial water reverse osmosis system to solve the most common problems for a variety of industrial and commercial water treatment processes. The system uses the latest in low-energy, high-efficiency membrane technology to produce reliable high-quality water and also provides the customer with the lowest possible operating costs. “Our new system is a complete solution

designed for the most demanding commercial, industrial, and municipal applications,” said Matt Burns, product manager at Culligan. “Not only does the low-energy membrane technology remove more than 99 percent of contaminants, including dissolved minerals, bacteria, and other impurities, but it also produces water suitable for high-purity applications, such as boiler feed and ingredient water for food and beverage production.” Available for flow requirements from 22 to 200 gpm, with salinity levels up to 4,500 ppm, the system suits applications such as the pretreatment for high-purity requirements, biopharmaceutical manufacturing, water jet cutting, potabilization for drinking water, power generation, and more. The unit is fully skidmounted for fast and easy onsite installation. The system’s modular design allows commercial and industrial customers to select from a wide range of predesigned options and configure the reverse osmosis to their exact requirements. Each of these options can be selected with Culligan’s configurator tool, which offers nearly 100 different pre-engineered combinations of features to be built into a perfect reverse osmosis application. This also allows Culligan to guarantee the highest quality American construction and a

best-in-class delivery time frame, with units shipping just three weeks from the order date. A unique benefit of the modular platform is that the system can be outfitted with a variety of custom options, including a Culligan-exclusive microprocessor controller or a Culligan PLC touchscreen control, coldwater configurations, chemical dosing stations to prevent membrane scaling with antiscalant or to remove chlorine with sodium bisulfite, integrated permeate flushing tanks, advanced monitoring instruments, and integrated cleaning-in-place systems. (www.culligan.com)

Cairox CR Potassium Permanganate tablets from Carus are designed to treat hydrogen sulfide odors in municipal wastewater when the use of feed equipment is not practical. They can be easily deployed in polyester mesh bags in remote sites, lift stations, and manhole applications. Controlled release technology allows the tablets to begin reacting with hydrogen sulfide and other odor-producing compounds in seconds. Tablets are passive, prevent sulfide-based corrosion, and eliminate the health risks associated with hydrogen sulfide exposure. (www.caruscorporation.com) S

Florida Water Resources Journal • February 2017

FWEA COMMITTEE CORNER Welcome to the FWEA Committee Corner! The Public Relations Committee of the Florida Water Environment Association hosts this article to celebrate the success of recent association chapter activities and inform members of upcoming events. To have information included for your chapter, send the details via email to Lindsay Marten at Lindsay.Marten@stantec.com.

New Seminar to Address Wastewater Process Ephemeralization Laurel Rowse

he FWEA Wastewater Process Committee focuses on the areas of wastewater process design and operations and supports FWEA’s mission and vision in this area. The committee hosts seminars on relevant wastewater process topics in different parts of Florida, providing professional development opportunities for FWEA members. The committee members have organized an excellent lineup of speakers for the upcoming FWEA Wastewater Process Seminar. We are excited to encourage FWRJ readers and their colleagues to attend the seminar, “Wastewater Process Ephemeralization: Treat-

ing More with Less,” to be held on Thursday, Feb. 23, 2017, from 8:00 a.m. to 4:30 p.m., at Miami Dade Water and Sewer Department, 3071 S.W. 38th Ave., in Miami. The seminar will include some returning and some new speakers from the February 2016 seminar held in Tampa. Additional information is located on the Wastewater Process Committee page at www.fwea.org. Online registration is now open. For more information contact David Hernandez, seminar planning chair, at dhernandez@hazenandsawyer.com. In addition to planning this seminar, the committee has been organizing the monthly Process Page article in this magazine. The articles have been highlighting wastewater treatment and water reclamation facilities that have won the Earl B. Phelps award in 2016. Kevin Vickers, Wastewater Process Committee Publications Subcommittee chair, has

been organizing the effort and many others have contributed articles. In February 2017, applications will be due for this year’s Earle B. Phelps Awards. Tina Nixon, the Phelps Award Subcommittee chair, and Wastewater Process Committee members will be evaluating the nominees and will select winners for the awards. We encourage nominations for wastewater treatment facilities of different sizes that represent excellence! My co-chair, Tim Ware, P.E., and I welcome FWEA members located anywhere in Florida to join our committee. Please contact Ivy Drexler, who coordinates committee membership, at idrexler@co.pinellas.fl.us. We hope to see you in Miami in February 2017 for a great seminar! Laurel Rowse is a water/wastewater staff engineer with AECOM in Tampa and is co-chair of the FWEA Wastewater Process Committee. S

Speakers from the committee's 2016 seminar in Tampa include (left to right): Albert Bock, Bay County Military Point Advanced Wastewater Treatment Plant; Jeff Peeters, GE Water and Process Technologies; and Mari Winkler, University of Washington.

February 2017 • Florida Water Resources Journal

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Water Quality and Supply Issues? Thereâ&#x20AC;&#x2122;s A Wetland for That! Chris Keller or many in the environmental profession, their experience with wetland ecosystems has been in the context of avoiding and minimizing impacts during the design, permitting, and construction of various infrastructure and land development projects. Most engineers and scientists are at least familiar with the extensive local, state, and federal permitting that is required when natural wetlands are encountered on project sites. Part of the reason that wetlands are protected is for the flood attenuation, water quality improvement, and wildlife habitat values they provide. Over the last half century, recognition of the intrinsic water quality functions provided by

natural wetlands has led to the intentional design of wetland projects, both natural and constructed, to meet specific water quality and supply objectives. In Florida, and across the United States, treatment wetlands have been used to provide secondary and tertiary treatment and disposal of industrial and municipal wastewaters, for the treatment and management of agricultural and urban stormwater, and for the beneficial reuse of high-quality reclaimed water. Representative Florida treatment wetland projects are described as a demonstration of their broad applicability to improve water quality, create wildlife habitat, and provide recreational and educational opportunities. General

Table 1. Wetland Removal Processes and Estimated Performance Limits for Common Water Quality Parameters

Chris Keller, P.E., is president of Wetland Solutions Inc. in Gainesville.

performance expectations, operations and maintenance requirements, and permitting considerations are also briefly described.

Treatment Wetlands Background While previously considered by some to be an experimental or unproven technology, treatment wetlands have been studied in great detail during the last 30 years. At the present point in the evolution of the technology, design methods are well-established and performance can be reliably estimated for a wide range of water quality parameters. Numerous technical references are available that describe the performance of treatment wetlands for a wide range of applications. An abridged list of references includes the following: S Treatment Wetlands (Kadlec and Knight, 1996) S Constructed Wetlands for Livestock Wastewater Management (CH2M and Payne Engineering, 1997) S The Use of Treatment Wetlands for Petroleum Industry Effluents (API, 1998) S Treatment Wetland Habitat and Wildlife Use Assessment Project (CH2M,1998) S Free Water Surface Wetlands for Wastewater Treatment: A Technology Assessment (USEPA, 1999) S Constructed Wetlands for Pollution Control Processes, Performance, Design, and Operation (IWA, 2000) S Constructed Wetlands Treatment of Municipal Wastewaters (USEPA, 2000) S Use of Constructed Wetland Effluent Treatment Systems in the Pulp and Paper Industry (Knight, 2004) S Small-Scale Constructed Wetland Treatment Systems Feasibility, Design Criteria, and Operations and Maintenance Requirements (Wallace and Knight, 2006) S Treatment Wetlands (Kadlec and Wallace, 2009) Continued on page 48

February 2017 â&#x20AC;˘ Florida Water Resources Journal

Continued from page 46 S Evaluate Wetland Systems for Treated Wastewater Performance to Meet Competing Effluent Water Quality Goals (Brooks et al., 2011)

Figure 1. Orlando Easterly Wetlands Site Plan and Monitoring Locations (Rothfield, 2016)

Wetlands are widely applicable as a water quality improvement technology because they naturally provide a suite of pollutant removal mechanisms that include physical, chemical, and biological processes. Treatment wetland performance is best described by first-order equations that estimate outflow concentration as a function of the inflow concentration, hydraulic loading rate (flow divided by surface area), removal rate coefficient, and, for some constituents, an irreducible background concentration (Kadlec and Wallace, 2009). Modifiers for hydraulic efficiency and temperature effects are also incorporated when appropriate. The use of simple concentration or mass removal efficiencies, as is common with stormwater best management practice sizing approaches, is inadequate for wetland design purposes, especially when specific permit standards must be met. Table 1 summarizes the dominant wetland pollutant removal mechanisms and the approximate limits of the technology for common water quality parameters.

Operations and Maintenance Requirements

Figure 2. Historical Flow, Total Nitrogen, and Total Phosphorus for the Orlando Easterly Wetlands (Rothfield, 2016)

February 2017 â&#x20AC;˘ Florida Water Resources Journal

Unlike conventional wastewater treatment systems, treatment wetlands have few moving parts that provide operational control. Treatment wetland operation is primarily based on establishing and maintaining a water depth regime and hydraulic loading rate that is within the hydrologic tolerance of the desired plant community. Water level management and water quality monitoring are the key components of a treatment wetland operational plan. Because wetlands typically have hydraulic residence times measured in weeks or months, the impact of operational adjustments may take some time to become evident at the wetland outfall. Treatment wetland maintenance requirements include routine inspections of flow delivery and water control structures, embankment mowing, and vegetation management. Active control of less desirable wetland plant species may be important when treatment systems are open for public access or are highly visible, but can be minimal for closed systems. With appropriate design, construction, and management, treatment wetlands can be expected to provide an operational lifespan of several decades before rehabilitation may be necessary.

Regulatory Considerations In Florida, the use of natural wetlands for effluent polishing and disposal is regulated under Ch. 62-611 of the Florida Administrative Code (F.A.C.). The “wastewater-to-wetlands rule” establishes allowable hydraulic loading rates and inflow water quality limits that are intended to preserve the structure and function of the natural wetland being used for water quality enhancement. The rule requires detailed baseline and operational monitoring for water quality, hydrology, vegetation cover, fish, and benthic macroinvertebrates. The operation of constructed domestic or industrial treatment wetlands is not regulated under Ch. 62-611, but rather is permitted under domestic and industrial wastewater rules (Chs. 62-600 and 62-620) with receiving water limits established under Ch. 62-302. In cases where the wetland is classified as a “reuse system,” elements of Ch. 62-610 also apply. Most stormwater treatment wetland projects (new construction and retrofits) are permitted under the Statewide Environmental Resource Permit (SWERP) rules because they involve changes to existing drainage patterns, but may not require the establishment and documented compliance with specific water quality standards at the point of discharge to the natural receiving system.

Selected Florida Wetland Projects Selected Florida treatment wetland projects are summarized to demonstrate the applicability of the technology for a variety of source waters. Municipal Wastewater Treatment: Orlando Easterly Wetlands The Orlando Easterly Wetlands (OEW) was implemented in 1987 to meet stringent nutrient limitations for effluent discharged from the Iron Bridge Water Reclamation Facility to the St. John’s River and its tributaries. The Florida Department of Environmental Protection (FDEP) established total nitrogen (TN) and total phosphorus (TP) limits of 2.31 and 0.20 mg/L, respectively, for surface water discharges and upgrading of Iron Bridge facility to advanced wastewater treatment (AWT) standards and providing final effluent polishing in a treatment wetland, which was determined to be the city’s most cost-effective, long-term solution. The total capital cost for land acquisition, pipeline construction (12 mi from the Iron Bridge facility to OEW), wetland creation, and planting was about $21.5 million. Annual operational costs were reported to be about

$450,000, excluding compliance monitoring (Mark Sees, personal communication, Feb. 16, 2016). The approximately 1,200-acre system is comprised of 18 individual wetland cells spanning a range of wetland plant community types (Figure 1). The system is currently permitted to receive 35 mil gal per day (mgd) of AWT effluent from the Iron Bridge facility. Figure 2 shows the annual average discharge from the OEW and inflow and outflow TN and TP concentrations (Rothfield, 2016). For the period from 1988 through 2015, the OEW treated 15.7 mgd. Inflow TN declined in 1990 after AWT upgrades were completed and averaged about 1.9 mg/L between 1990 and 2015; outflow TN concentrations from the OEW averaged 0.88 mg/L. Inflow and outflow TP averaged 0.23 and 0.06 mg/L, respectively. The OEW outflow annual average TN and TP concentrations have consistently been well below the regulatory standards. The OEW system is one of few large-scale municipal wastewater treatment wetlands in the United States that has undertaken sediment and vegetation removal maintenance actions to improve hydraulic efficiency and extend system life. These actions have included burning accumulated thatch, excavating and removing accreted organic sediments, and transitioning open water areas to submerged aquatic vegetation (SAV). Public access and recreational use of the OEW system is an important part of the city’s overall management plan. The park-like system is open year-round and attracts over 15,000 visitors annually. The city has also partnered with the University of Florida for collaborative research studies that have resulted in publication of several graduate-level projects and theses. Industrial Wastewater Treatment: PurEnergy LLC PurEnergy LLC operates a 15 megawatt (MW) biomass-fueled power-generating facility in the Florida panhandle. Operation of the facility produces an intermittent discharge of nonprocess boiler blowdown, noncontact cooling water, and neutralized reverse osmosis brine. Because the effluent discharge is typically much warmer than the background stream temperature, raw well water was historically used for temperature adjustment. Event-based stormwater discharges from ash pile sedimentation ponds and drainage ditches blend with the industrial effluent and discharge to an unnamed tributary of a major rural creek system. In 2012, a treatment wetland system was designed in response to periodic exceedances of effluent limitations for acute toxicity, copper,

pH, temperature, unionized ammonia, and specific conductance. The design approach followed the first-order P-k-C model described by Kadlec and Wallace (2009) using conservative removal rate coefficients for ammonia of 14.7 meters per year (m/yr) and for copper of 25 m/yr. Sizing for ammonia removal established the final surface flow wetland area of 4.6 acres. At the design average discharge rate of about 0.1 mgd and average operating depth of about 0.75 ft, the nominal hydraulic residence time was estimated to be approximately 11 days. Energy balance calculations were prepared to estimate the amount of effluent cooling that could be expected in the treatment wetland. The design for pH and toxicity was presumptive, in that by sizing for copper and ammonia removal, the resulting residence time would be adequate to neutralize final effluent pH and reduce the likely cause (unionized ammonia) of prior toxicity violations. Specific conductance was not expected to be changed with passage through the wetlands, except by dilution with rainfall. Project construction commenced in October 2012, with the first of two cells completed and receiving continuous effluent flow by September 2013; the second cell became operational in January 2014. The total construction cost, including engineering and permitting, was about $300,000. Operational costs consist of electrical power for pumping to the wetland, water quality sampling and analysis, periodic embankment mowing, and routine report preparation for FDEP, and have not been quantified. The fully completed project has now been in continuous operation for about three years, during which time the average inflow rate was about 0.12 mgd, exceeding the design assumption of 0.1 mgd. In spite of the increased flow, water quality performance has been excellent for the primary design parameters. Wetland total ammonia concentrations were reduced from about 0.16 mg/L (as N) to below the laboratory detection limit of 0.1 mg/L (as N). Wetland outflow unionized ammonia concentrations have averaged less than 0.001 mg/L. Total copper concentrations were reduced by an order-ofmagnitude from about 0.03 mg/L to 0.003 mg/L. Wetland inflow and outflow pH averaged 8.06 and 7.24 standard units, respectively. All required effluent toxicity tests were passed with no mortality observed in the test organism populations. Specific conductance declined from about 1,400 to 1,200 µmhos/cm. Effluent temperatures were reduced by about 5°C during the summer months. As part of the renewal process for the facility's industrial wastewater discharge permit, a Continued on page 50

Florida Water Resources Journal • February 2017

Continued from page 49 detailed temperature study was conducted to document daily temperature variability at the inflow to the wetland, at the wetland outlet, and in nearby reference stream systems. This analysis showed that the wetland effluent was cooled to the maximum extent possible based on local climate conditions, and that forced additional cooling by blending cooler groundwater with the effluent (one previously recommended alternative) was not an environmentally sound use of the resource and would not increase protection of the receiving aquatic ecosystem. The FDEP agreed with this finding and removed

temperature from the permit conditions when the permit was reissued in October 2015. Stormwater Treatment: Everglades Agricultural Area and Stormwater Treatment Areas Based on the documented success of longterm treatment wetland projects across the U.S. and cost-effectiveness analyses comparing wetlands to conventional treatment approaches in the early 1990s, the South Florida Water Management District (SFWMD) began constructing large treatment wetlands, or stormwater treatment areas (STAs), to reduce phosphorus loads delivered to the Everglades protection area from

Figure 3. Location Map for the South Florida Water Management District Everglades Agricultural Area Stormwater Treatment Areas (SFWMD, 2016)

Table 2. Period-of-Record Operational Performance Summary for the South Florida Water Management District Everglades Agricultural Area Stormwater Treatment Areas (SFWMD, 2016)

Lake Okeechobee and the canal systems of the Everglades agricultural area (EAA). The prototype system, known as the Everglades Nutrient Removal Project (ENRP, later renamed STA-1W) was designed using a first-order, steady-state equation, with the goal of achieving a long-term average outflow total phosphorus (TP) concentration of 50 parts per bil (ppb). Data collected from ENRP and other Florida treatment wetlands were used to develop and calibrate the dynamic model for stormwater treatment areas (DMSTA), which has become the primary planning and design process model used for all subsequent STA projects. At present, SFWMD has constructed over 57,000 acres of STAs to improve water quality leaving the EAA (Figure 3). Individual STA systems range in size from about 5,000 to more than 16,000 acres. The STA-3/4, at about 16,300 acres, is the largest treatment wetland system in the world. Each STA consists of multiple compartments or cells, which range from 242 acres (STA-5/6 Cell 6-3) to 3,456 acres (STA-3/4 Cell 1B) in size (SFWMD, 2016). Over the operational period of record, the EAA STAs have treated about 5.6 tril gal of agricultural runoff, reduced loads by 76 percent by retaining about 2,220 metric tons (mt) of TP, and reduced TP concentrations from a flowweighted mean inflow value of 135 ppb to a flow-weighted mean outflow value of 32 ppb (SFWMD, 2016). Table 2 provides period-ofrecord operational data for the individual STAs. The total program cost has exceeded $1.8 billion (SFWMD, 2014). Through an intensive data collection and research program driven by the need to maximize treatment effectiveness and minimize outflow TP concentration, SFWMD has made significant contributions to the treatment wetlands knowledge base. One of the key study areas has been related to the differences in TP performance as a function of wetland plant community type. Site-specific research-scale work that began in the late 1990s showed that SAV provided the capability of achieving lower-outflow TP concentrations than emergent aquatic vegetation (EAV). Other key research efforts have focused on the stability of TP in newly accreted wetland sediments, the effects of tropical weather systems on wetland structure and performance, and the management of systems across highly variable hydrologic conditions. Municipal Wastewater Treatment and Groundwater Recharge: Ichetucknee Springshed Water Quality Improvement Project A relatively recent development in treatment wetland technology in Florida has been Continued on page 52

February 2017 â&#x20AC;˘ Florida Water Resources Journal

FWPCOA TRAINING CALENDAR SCHEDULE YOUR CLASS TODAY! February 13-15 ..........Backflow Repair* ..................St. Petersburg ......$275/305

March 13-17 ..........Spring State Short School ....Ft. Pierce 27-30 ..........Backflow Tester* ....................St. Petersburg ......$375/405

May 15-18 ..........Backflow Tester* ....................St. Petersburg ......$375/405

June 19-21 ..........Backflow Repair* ..................St. Petersburg ......$275/305

July 10-13 ..........Backflow Tester* ....................St. Petersburg ......$375/405

August 28-30 ..........Backflow Repair* ................St. Petersburg ......$275/305

Course registration forms are available at http://www.fwpcoa.org/forms.asp. For additional information on these courses or other training programs offered by the FWPCOA, please contact the FW&PCOA Training Office at (321) 383-9690 or training@fwpcoa.org. * Backflow recertification is also available the last day of Backflow Tester or Backflow Repair Classes with the exception of Deltona ** Evening classes

You are required to have your own calculator at state short schools and most other courses.

*** any retest given also Florida Water Resources Journal â&#x20AC;¢ February 2017

Continued from page 50 the use of wetlands to reduce nutrients before water infiltrates to potable water aquifers. These groundwater recharge wetland systems operate similarly to rapid infiltration basins (RIBs), but maintain wetland hydrology and vegetation. De facto infiltrating systems in South Florida (the Wakodahatchee Wetlands and Green Cay Wetlands) have proven effective at providing reliable treatment and infiltration over a 10- to 20-year time frame. More recently, several higher-rate demonstration-scale systems were constructed and monitored by Gainesville Regional Utilities (GRU). Data from these demonstration wetlands showed exceptional nitrogen removal capacity at sustainable infiltration rates, making the concept a viable alternative to spray irrigation or RIB disposal systems (WSI, 2012; WSI, 2013). These recharge wetland systems have also been permitted to take advantage of excess capacity in dry stormwater retention areas. By providing both treatment and disposal in the same project footprint, groundwater recharge wetlands offer utilities, industry, and water managers a cost-effective alternative to replenish aquifer levels with high-quality water. The recently completed Ichetucknee Springshed Water Quality Improvement Project (ISWQIP) in Lake City was the first large-scale conversion of an existing spray field to a groundwater recharge wetland. The $5.6 million project was cooperatively funded by FDEP, Suwannee River Water Management District, Columbia County, and City of Lake City. Effluent from the city’s St. Margaret’s Water Reclamation Facility meets current effluent limitations, but the project was implemented under the Santa Fe River Basin Management Action Plan (BMAP) to reduce regional TN loads and provide beneficial recharge to the Upper Floridan aquifer and the Ichetucknee Springs system. The project consists of nine interconnected wetland cells totaling about 120 acres of effective treatment area. Applied effluent travels through the wetland cells before recharging the aquifer through two soil modification zones that were installed when the spray field was constructed in the mid-1980s and through natural breaks in the confining clay layer that separate the surficial sands from the underlying lime-

stone formation. Wetland water quality process modeling prepared during the design and permitting phase (Table 3) estimated that the wetland surface water compartment would reduce TN from about 6.4 to 1.0 mg/L, and nitrate+nitrite-nitrogen, the target parameter for springs protection, from about 1.9 to 0.2 mg/L, at an annual average flow of 1.2 mgd (WSI, 2015).

•

Conclusions • The projects described illustrate some of the ways that treatment wetlands have been used to enhance water quality and supply in Florida, but there are also other local examples, such as using coastal wetlands for reverse osmosis brine disposal and constructed marshes to reduce algal solids and nutrients from eutrophic lake waters, that are not described. The ability to cost-effectively transform a wide variety of pollutants into harmless end products, while creating valuable wildlife habitat and providing opportunities for passive recreation and education, make treatment wetlands an obvious alternative to consider for any water quality improvement project.

References • American Petroleum Institute, 1998. “The use of treatment wetlands for petroleum industry effluents.” Prepared by CH2M for the API Biomonitoring Task Force, Health and Environmental Sciences Department, Washington, D.C. • Brooks, B.W.; Chambliss, K.C.; Sedlak, D.L.; and Knight, R.L., 2011. “Evaluate Wetland Systems for Treated Wastewater Performance to Meet Competing Effluent Water Quality Goals.” WateReuse Research Foundation, Alexandria, Va. • CH2M and Payne Engineering, 1997. “Constructed Wetlands for Livestock Wastewater Management: Literature Review, Database, and Research Synthesis.” Report prepared for the Gulf of Mexico Program, Nutrient Enrichment Committee, Stennis Space Center, Miss. • CH2M, 1998. “Treatment Wetland Habitat and Wildlife Use Assessment Project.” Report prepared for the U.S. Environmental Protec-

Table 3. Estimated Annual Average Inflow and Outflow Concentrations for the Ichetucknee Springshed Water Quality Improvement Project (WSI, 2015)

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February 2017 • Florida Water Resources Journal

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tion Agency, U.S. Bureau of Reclamation, and City of Phoenix, with funding from the Environmental Technology Initiative Program. International Water Association, 2000. “Constructed Wetlands for Pollution Control: Processes, Performance, Design and Operation.” Scientific and Technical Report No. 8. IWA Publishing, London, England, 156 pp. Kadlec, R. H.; Knight. R. L., 1996. “Treatment Wetlands.” CRC Press, Boca Raton, Fla. Kadlec, R. H.; Wallace, S.D. 2009. Treatment Wetlands, Second Edition. CRC Press, Taylor & Francis Group, Boca Raton, Fla. Knight, R. L. 2004. “Use of constructed wetland effluent treatment systems in the pulp and paper industry.” Technical Bulletin No. 876. Report for the National Council of the Paper Industry for Air and Stream Improvement Inc. Rothfield, K. 2016. “Orlando Easterly Wetlands Compliance and Performance Review for the City of Orlando’s Easterly Wetlands Treatment System,” 2015Annual Report. Prepared for the Florida Department of Environmental Protection. South Florida Water Management District (SFWMD). 2016. Draft 2017 South Florida Environmental Report. SFWMD. 2014. “Below the Surface: An InDepth Look at Everglades Stormwater Treatment Areas.” SFWMD Fact Sheet. U.S. Environmental Protection Agency, 1999. “Free Water Surface Wetlands for Wastewater Treatment: A Technology Assessment.” EPA/832/R-99/002, Washington, D.C. U.S. Environmental Protection Agency, 2000. “Design Manual: Constructed Wetlands Treatment of Municipal Wastewater.” EPA/625/R99/010, Washington, D.C. Wallace, S. D.; Knight, R. L., 2006. Small-Scale Constructed Wetland Treatment Systems: Feasibility, Design Criteria, and O&M Requirements.” Final Report for the Water Environment Research Foundation, Alexandria, Va. Wetland Solutions Inc. (WSI), 2015. “Ichetucknee Springshed Water Quality Improvement Project: Updated Water Quality Performance Estimates.” Prepared for AMEC Foster Wheeler. WSI, 2013. “Kanapaha Water Reclamation Facility Infiltrating Wetlands Demonstration Project: Data Report.” (June 2012–September 2013). Prepared for Gainesville Regional Utilities. WSI, 2012. “Kanapaha Water Reclamation Facility Infiltrating Wetlands Demonstration Project Data Report.” (March 200–October 2011). Prepared for Gainesville Regional Utilities. S

FWEA FOCUS

2017 WEF Nutrient Symposium in Fort Lauderdale Lisa Prieto President, FWEA s many of you know, the Water Environment Federation (WEF) holds technical seminars and symposiums in conjunction with partner associations across the globe. The Federation moves these technical events around the country so that different audiences can attend and participate in these premier events. We are fortunate that this year the WEF Nutrient Symposium will be held June 12-14 at the Hyatt Regency in Fort Lauderdale. Nutrient removal systems have been successfully operated for decades; however, the wastewater industry is currently facing dramatic changes, shifting away from energy-intensive wastewater treatment and toward low-energy, sustainable technologies capable of achieving energy-positive operation while recovering important resources. As a response to this dramatic change in the wastewater industry, researchers are working with practitioners and operators to develop innovative solutions to support the needs of our industry. This symposium will bring together environmental professionals to discuss and debate the current state of the art for nutrient removal, recovery, and management, and the parameters that influence technology boundaries. It will provide a forum for the discussion of research collaboration to promote the rapid application of new and innovative solutions for nutrient removal and recovery. Additionally, it will examine research, design, operations, and planning of nutrient resource management and also provide a platform for the discussion of policy approaches to nutri-

ent control, with an eye on the environmental and economic aspects. It will provide valuable information for researchers, regulators, designers, technology developers, operators, municipal agencies, industrial dischargers, and others seeking to understand the full picture of the latest developments and practical experiences on this important topic. The program, along with registration and sponsorship information, can be found online at www.wef.org/nutrients. The tracks are as follows: S Carbon Redirection S Biological Nutrient Removal Process Control S Watershed Management S Phosphorus Removal S Sidestream Shortcut Nitrogen Removal S Interesting Case Studies S Integrating Ion Exchange S Granular Sludge S Nutrient Recovery S Emerging Biofilms S Mainstream Shortcut Nitrogen Removal S Membrane Aerated Biofilm Reactor The symposium will provide an excellent opportunity to interact with an exciting roster of nationally and internationally recognized experts in the field of nutrient removal and recovery technology. It will also provide opportunities to learn how researchers are working alongside practitioners and operators to design and implement innovative solutions to address the challenges of sustainable nutrient management issues in today’s world. The deadline for early bird registration is May 12, and there are member discounts. For questions about this conference contact WEF or your local FWEA chapter, which can direct you to the correct person to help you out. Hope to see you there! S

February 2017 • Florida Water Resources Journal

News Beat Mike McGee, P.E., BCEE, with TKW Consulting Engineers Inc. in Fort Myers, recently qualified for specialty certification by the American Academy of Environmental Engineers and Scientists as a board-certified environmental engineer in water supply and wastewater. This designation is for licensed professional engineers who have demonstrated their experience as engineers in responsible charge, and by examination and an interview with a panel of peers, that they meet the strict requirements for this specialty certification. He is now one of only 117 professional engineers in the state of Florida holding this qualification in water supply and wastewater. McGee was also recently promoted to principal engineer and environmental/utilities engineering department manager of the firm. He has more than 25 years of diversified civil engineering experience, with a focus on water, wastewater, and reclaimed water projects. Considered an expert in horizontal directional drill and other trenchless pipeline construction technologies, he has designed and permitted numerous directional drills of water, reclaimed water, and wastewater transmission pipelines throughout southwest Florida. He has a master’s degree in civil engineering from Auburn University and is a graduate of the United States Naval Academy.

The Water and Wastewater Equipment Manufacturers Association (WWEMA) and Boenning & Scattergood Inc. have released the report, “2016 3Q WWEMA/Boenning Leading Demand Index,” which provides insight into near-term market and funding conditions related to municipal water and wastewater projects. According to the report, the index increased slightly in the third quarter, reversing the recent downward trend and suggesting an improving outlook for water and wastewater infrastructure products in 2017. According to the report’s author, Ryan Connors, managing director at Boenning & Scattergood, this indicates that the outlook for the sector appears to be improving. A review of the market and the key five factors that make up the index indicate that water and wastewater utilities are continuing to expand their payrolls, water and wastewater equipment demand has improved notably in recent months, water stocks rebounded sharply in the third quarter, ductile iron pipe prices reversed their secondquarter slide, and the housing market remains a wild card that could complicate the recovery.

The full report includes charts relating to these factors, depicting data and trends dating back three to five years, as well as additional background and analysis. It is available exclusively to WWEMA members. For information on WWEMA and membership, visit www.wwema.org

The Water Environment & Reuse Foundation (WE&RF) has entered into a memorandum of understanding (MOU) with the National Water Research Institute (NWRI), a nonprofit organization based in Southern California, to jointly pursue projects and initiatives that improve the reliability and resiliency of water resources, including stormwater, groundwater, and recycled water. “WE&RF and NWRI are formalizing their relationship through this MOU to pursue mutually beneficial, cost-sharing, and staffing agreements for projects and initiatives that provide benefits to their respective members and the entire water sector,” said Melissa Meeker, WE&RF chief executive officer. Both WE&RF and NWRI regularly convene scientists, researchers, policymakers, and industry leaders to share knowledge and innovations in water use, reuse, recovery, and resources. Additionally, they both have an extensive network of nationally and internationally recognized experts to serve as researchers, peer reviewers, and advisors for research, pilot projects, and programs in the water industry. “Under this agreement, our organizations seek to enhance efforts in the water research industry,” said James Ferryman, president of NWRI’s board of directors. “It will ensure sustainable sources of water through more integrated water management efforts.” Examples of efforts the two organizations will jointly undertake include: S Host the 2017 International Water Association Water Reuse Specialty Conference in Long Beach, Calif. S Joint research to develop an advanced water technology validation program. S Communicate the immediate and potential implications of implementing direct potable water reuse. S Support local projects that may serve as a catalyst for expanding water reuse. Without additional state and federal funding committed to Everglades restoration, the greater Everglades ecosystem is threatened by prolonged and significant ecological damage, according to a report released by the National Research Council Committee on Independent Science Review of Everglades Restoration. Continued on page 61 Florida Water Resources Journal • February 2017

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Utilities Treatment Plant Operations Supervisor $57,116 - $80,367/yr.

Utilities Electrician $51,283 - $72,160/yr.

Utilities Treatment Plant Operator I $44,300 - $62,334/yr.

Utilities System Operator II & III $38,267 - 53,847/yr.; $40,182 - $56,539/yr. Apply Online At: http://pompanobeachfl.gov Open until filled.

Reiss Engineering, Inc. Looking for an opportunity to make a difference? Looking for a dynamic team environment where you can manage and lead projects to success? Reiss Engineering is seeking top-notch talent to contribute and make a difference for our people, our clients, and our community! Reiss Engineering delivers highly technical water and wastewater planning, design, and construction management services for public agencies throughout Florida. To see open positions and submit a resume to join our team, visit www.reisseng.com.

Orange County, Florida is an employer of choice and is perennially recognized on the Orlando Sentinel’s list of the Top 100 Companies for Working Families. Orange County shines as a place to both live and work, with an abundance of world class golf courses, lakes, miles of trails and yearround sunshine - all with the sparkling backdrop of nightly fireworks from world-famous tourist attractions. Make Orange County Your Home for Life. Orange County Utilities is one of the largest utility providers in Florida and has been recognized nationally and locally for outstanding operations, efficiencies, innovations, education programs and customer focus. As one of the largest departments in Orange County Government, we provide water and wastewater services to over 500,000 citizens and 66 million annual guests; operate the largest publicly owned landfill in the state; and manage in excess of a billion dollars of infrastructure assets. Our focus is on excellent quality, customer service, sustainability, and a commitment to employee development. Join us to find more than a job – find a career. We are currently looking for knowledgeable and motivated individuals to join our team, who take great pride in public service, aspire to create a lasting value within their community, and appreciate being immersed in meaningful work. We are currently recruiting actively for the following positions:

Industrial Electrician I $36,733 – $43,035/ year Apply online at: http://www.ocfl.net/jobs. Positions are open until filled.

CITY OF WINTER GARDEN – POSITIONS AVAILABLE The City of Winter Garden is currently accepting applications for the following positions:

City of Groveland Class C Wastewater Operator The City of Groveland is hiring a Class "C" Wastewater Operator. Salary Range $30,400-$46,717 DOQ. Please visit groveland-fl.gov for application and job description. Send completed application to 156 S Lake Ave. Groveland, Fl 34736 attn: Human Resources. Background check and drug screen required. Open until filled EOE, V/P, DFWP

- Traffic Sign Technician - Water Plant Operator – Class C - Wastewater Plant Operator Trainee - Solid Waste Worker II - Collection Field Tech I & II - Distribution Field Tech I & II Please visit our website at www.cwgdn.com for complete job descriptions and to apply. Applications may be submitted online, in person or faxed to 407-877-2795. Florida Water Resources Journal • February 2017

Water Production Operations Supervisor The City of Melbourne, Florida is accepting applications for an Operations Supervisor at our water treatment facility. Applicants must meet the following requirements: High School diploma or G.E.D., preferably supplemented by college level course work in mathematics and chemistry. Five years supervisory experience in the operation and maintenance of a Class A water treatment facility. Possession of a Class A Water Treatment Plant Operator license issued by the State of Florida. Must possess a State of Florida driver’s license. Applicants who possess an out of state driver’s license must obtain a Florida license within 10 days of employment. Must have working knowledge of nomenclature of water treatment devices. A knowledge test will be given to all applicants whose applications meet all minimum requirements. Salary Range: $39,893.88 - $67,004.60/AN, plus full benefits package. To apply please visit www.melbourneflorida.org/jobs and fill out an online application. The position is open until filled. The City of Melbourne is a Veteran's Preference /EOE/DFWP.

Electronic Technician The City of Melbourne, Florida is accepting applications for an Electronic Technician at our water treatment facility. Applicants must meet the following requirements: Associate’s degree from an accredited college or university in water technology, electronics technology, computer science, information technology, or related field. A minimum of four (4) years’ experience in the direct operation, maintenance, calibration, installation and repair of electrical, electronic equipment, and SCADA systems associated with a large water treatment facility. Experience must include field service support and repair of PLC’s, HMI, SCADA, programming VFD’s, switchgear and working in an industrial environment. Desk/design work does not count toward experience. Must possess and maintain a State of Florida Journeyman Electrician License. Must possess and maintain a valid State of Florida Driver's license. Applicants who possess an out of state driver’s license must obtain the Florida license within 10 days of employment. Salary Range: $40,890.98 - $68,680.30/yr, plus full benefits package. To apply please visit www.melbourneflorida.org/jobs and fill out an online application. The position is open until filled. The City of Melbourne is a Veteran's Preference /EOE/DFWP.

Process Controls Technician Town of Jupiter is seeking a full-time Process Controls Technician for its 30 MGD membrane water treatment plant and ancillary pumping systems. This position will perform technical work to install, maintain and calibrate all instrumentation, metering pumps, actuated valves and communication equipment. To view the full job description and to apply, please visit http://agency.governmentjobs.com/jupiterfl/default.cfm.

Marion County - Utilities Engineer $66,664.00 Must have degree in civil engineering or related field and five years of experience. Please apply at: www.marioncountyfl.org/careers

February 2017 • Florida Water Resources Journal

ENGINEERING TECHNICIAN III (N/S) The City of Tampa is accepting applications for experienced construction inspectors. The work entails sub-professional engineering assignments including compliance inspections on major municipal building, civil and utility capital improvement projects, and materials testing. Background check and drug screen required. See the full job description and apply at www.tampagov.net.

THE CITY OF DAYTONA BEACH WASTEWATER PLANT SUPERINTENDENT Regional WW Treatment Plant Annual Salary Range $50,752.08 - $94,758.12 January 20, 2017 – March 6, 2017 The purpose of this classification is to function as superintendent for the operations and maintenance of a Class A, Type I advanced wastewater treatment facility, meeting guidelines and standards set forth by the state and federal government. Employees in this classification perform middle management work for a 5 stage Bardenpho treatment plant, reclaimed water system, and auxiliary facilities. Position is responsible for assisting with planning, training, organizing, directing, and maintaining the uninterrupted flow of operations. This position directly supervises 7 operational personnel and 6 maintenance personnel. Performs related work as required. MINIMUM QUALIFACTIONS (Education, Training, and Experience): High School Diploma or GED; prefer Associate's degree with course work emphasis in higher mathematics and science or related; supplemented by five (5) years wastewater treatment operations, two (2) of which shall be acquired in a supervisory capacity in a wastewater treatment plant. SPECIAL REQUIREMENTS Requires valid State of Florida Driver’s License and Class “A” Wastewater Certification. For application, information, and submittal requirements, go to www.codb.us/jobs Job Opportunities EOE/AA/ADA/VET Employer

Mechanic I, II or III Skilled work in the operation, maintenance & repair of water treatment plant, well field, repump station, machines & facilities. HS diploma or acceptable equivalency diploma, Class A CDL required. For entire job description & to apply go to www.fpua.com.

USEPPA INN & DOCK COMPANY LTD - Useppa Island-Class C Utility Maintenance Tech

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Class C Water/Wastewater Plant on private island on the Inter-coastal Waterway in South West Florida is looking for a full-time maintenance technician. Pay is negotiable depending on experience. Experience preferred, licensing not required. Full Benefits package! Send all inquiries and resumes to smcmillen@useppa.com

Annual Salary Range: $57,054.40 -$94,161.60 Pinellas County Utilities is seeking a qualified candidate to supervise the Technical Services Section in the Utilities Department. This section is in charge of the meters, backflow prevention assemblies, cross connection control, various inspections and other duties. Please see the Pinellas County, Human Resources website for more information. To apply visit: https://employment.pinellascounty.org Apply by: February 26, 2017 EOE/AA/ADA/DFW/VP Certain service members and veterans, and the spouses and family members of the service members and veterans, receive preference and priority in employment by the state and are encouraged to apply for the positions being filled.

Brevard County Utility Services Dept. - Treatment Plant Operator - Wastewater Job 201703331 The Brevard County Utility Services Department is seeking a Treatment Plant Operator-Wastewater for a County-owned public water and sewer utility. For more information and to apply, please go to the Brevard County Board of County Commissioners employment website at www.brevardcounty.us/easy/. Position will be open from January 23, 2017 to February 27, 2017.

Severn Trent - Seeking Lead Water Operator! Seeking Lead Water Operator in Hialeah, FL. Must have a Class A FL Water license. Position is offering competitive pay and benefits. Please send resumes to Kelly.Moser@stservices.com

News Beat

Continued from page 55 “Audubon Florida’s long-standing position was reaffirmed when the report concluded that more water storage is needed in light of climate change and sea-level rise, with water quality in Lake Okeechobee still being an area of concern,” said Julie Hill-Gabriel, the organization’s deputy director. With Congressional approval of the Central Everglades Project (CEP), finding additional water storage options in the Everglades Agricultural Area (EAA) is even more important in light of these findings. The CEP will begin to open the pathway for water to flow south between Lake Okeechobee and the southern Everglades, but it does not contain the significant water storage outlet from Lake Okeechobee that a reservoir in the EAA would provide. The report also recommended reexamining conflicts between restoration objectives and the needs of protected species. Said HillGabriel, “Audubon Florida looks forward to finding solutions for endangered species and habitat protection, which is a paramount goal of Everglades restoration.” For more information, go to www.evergladesrestoration.gov. S

P o s itio ns Wante d JOHN PAGE – Holds a Florida C Wastewater and North Carolina Gr. 4 Wastewater with 33 years experience. Supervisor experience in construction, planning upgrades. Also has a North Carolina land application. Prefers Pasco, Pinellas, Hillsboro or west Orange County. Contact at 5517 Tulip Drive, New Port Richey, Fl. 34652. 7046167363 LOUIS HOGGS – Seeking a Trainee position and has a C Wastewater certificate and needs plant hours to obtain his license. Has CLP in CDL’s and has experience in general construction and basic management. Prefers the central Florida area (Seminole, Orange, Volusia, Osceola) Contact at louishoggs.17@gmail.com

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LOOKING FOR A JOB? The FWPCOA Job Placement Committee Can Help! Contact Joan E. Stokes at 407-293-9465 or fax 407-293-9943 for more information.

Florida Water Resources Journal • February 2017

Test Yourself Answer Key From page 37 1. A) The ability of a liquid to neutralize an acid. Another way to describe alkalinity is the ability of a liquid to buffer against a decrease in pH. Alkalinity is expressed in terms of calcium carbonate equivalent, as CaCO3.

Editorial Calendar January ........Wastewater Treatment February ......Water Supply; Alternative Sources March............Energy Efficiency; Environmental Stewardship April ..............Conservation and Reuse May................Operations and Utilities Management; Florida Water Resources Conference June..............Biosolids Management and Bioenergy Production July ..............Stormwater Management; Emerging Technologies; FWRC Review August ..........Disinfection; Water Quality September ....Emerging Issues; Water Resources Management October ........New Facilities, Expansions, and Upgrades November ....Water Treatment December ....Distribution and Collection

2. D) 1,000 times. A change in one pH unit is a factor of 10 times. For example, a decrease in pH from pH 7 to pH 6 is ten times more acidic. Each pH unit decrease is times 10, therefore a decrease to 4 from pH 7 is ten times ten times ten, or 1,000 times more acidic.

3. B) Nitrification is occurring. The biological oxidation process of nitrification consumes alkalinity at a rate of 7.1 mg for every mg of ammonium oxidized per liter.

4. A) 0.1 parts acid to one part alkalinity. There should be plentiful alkalinity to buffer against the volatile acids formed during acid production phases of anaerobic digestion. For example, if the anaerobic digester contains 250 mg/L of volatile acids, there should be about 2,500 mg/L of alkalinity, based on this ratio.

5. C) 7.1 mg. The 7.1 milligrams of bicarbonate and carbonate alkalinity are consumed by bacteria as a carbon source and for acid buffering for each milligram of ammonium oxidized to nitrite, then nitrate.

6. C) 0 – 14.

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February 2017 • Florida Water Resources Journal

The pH scale is 0 to 14 standard units (SU), and is a measurement of the activity of the hydrogen ion.

7. D) 260 mg/L. Multiply the influent ammonia mg/L value by 7.1 mg/L of alkalinity consumed per one part of ammonia oxidized: 36.5 mg/L x 7.1 mg/L = 259.15 mg/L.

8. D) The characteristics of the potable water supply influences alkalinity. A “hard” potable water supply will usually contain alkalinity as calcium or magnesium bicarbonate. Municipalities that use water softening processes like ion exchange or membrane softening units for their potable water may not replenish enough alkalinity to aid the wastewater treatment microorganisms, specifically nitrifying bacteria.

9. D) Lime supplements the water alkalinity and aids in complete precipitation of alum. If the surface water source (reservoir, lake, stream) does not contain sufficient natural alkalinity, lime may be added to increase the alkalinity and ensure complete aluminum precipitation in the sedimentation tanks. Otherwise, tiny aluminum flakes and a discoloration of the finished water may be observed at the sedimentation tank outlet weirs.

10. B) Overaeration causing nitrification. Too much dissolved oxygen from overaeration in an aerobic digester tends to cause excessive nitrification of the waste activated sludge. As alkalinity is depleted, the pH decreases, foaming increases, and the biosolids become difficult to dewater. Concrete structures begin to crumble at the air/liquid interface due to calcium being drawn out of the concrete itself.

A note to this month’s quiz-takers from the author: I recognize among operators and exam-takers a lack of understanding about the relationship between pH and alkalinity, in both drinking water and wastewater treatment processes. I hope that these questions will create a desire to learn more about this relationship and/or help potential examinees prepare for their test. Many process control and troubleshooting questions are based on pH and alkalinity, and thorough knowledge and comprehension of these principles can help obtain that passing score! Ron T.