Document Minden_doc_1d96041e82

MINDEN TOWN ARSENIC MITIGATION PLAN JULY 2020 Creating solutions that work and relationships that last ---PAGE BREAK--- © COPYRIGHT 2020 SUNRISE ENGINEERING, INC. MINDEN TOWN CULINARY WATER ARSENIC MITIGATION PLAN JULY 2020 CHAIRMAN JOHN STEPHANS VICE-CHAIRMAN SUSAN JACKSON BOARD MEMBER BERNARD BOARD MEMBER BILL DRISCOLL BOARD MEMBER ROXANNE STANGLE TOWN MANAGER FRISBY CITY CLERK JEFF CADY PREPARED BY: 11 North 300 West Washington, UT 84780 TEL: [PHONE REDACTED] FAX: [PHONE REDACTED] Joseph K. Phillips, P.E. Parry Osborn Project Engineer Project Engineer State of Nevada No. 017304 ---PAGE BREAK--- i Table of Contents Executive Summary 1 Literature Review 3 Background Information 3 Minden Town’s Water System and Arsenic History 3 Previous Arsenic Research 4 Mitigation Strategies 8 Pre-Distribution 9 Source Abandonment and Replacement 11 Source Reconfiguration/Seasonal or Limited Use 11 Treatment 11 Pre-Oxidation Processes 13 Point of Use 15 Treatment Processes 16 16 Enhanced Lime 17 Reverse Osmosis (RO) 17 Ion Exchange 19 Activated Alumina 20 Iron-Based Sorbents 21 Granular Ferric Hydroxide Media (GFH) 21 Ultrafiltration (UF) 22 Decision Matrix and 24 Capital Costs 25 Recommendations 26 Implementation Strategy 27 Conclusions 28 Appendix 1 – Arsenic 29 Appendix 2 – Treatment Equipment Information 32 Appendix 3 – Decision Matrix 69 Appendix 4 – Cost Estimates 71 Appendix 5 – Arsenic Data for Minden Town’s Wells 97 ---PAGE BREAK--- 7/20/2020 1 Executive Summary Minden Town is situated near the western border of Nevada in the Carson Valley. The Town owns and operates a public drinking water system that pumps water from several wells throughout the Town. There are nine wells currently in operation that provide drinking water to the Town’s system. Minden also wholesales water to some of the neighboring communities. The aquifer that Minden pulls water from receives its water from snowmelt from the surrounding mountains. There appear to be two different layers to the aquifer the upper layer, and the lower layer which are separated by low permeability clay (USGS). Due to the minerals and chemistry in the area, the aquifer water has dissolved arsenic in it. The upper layer in the aquifer tends to have arsenic in the oxidized form as arsenate or AS-V, while the lower level tends to have more prevalent arsenite or AS-III. The US Environmental Protection Agency (EPA) adopted a new rule in 2001 that required public drinking water systems to reduce the amount of total arsenic in the water supply to below 10 mg/L (or parts per billion, ppb). While most of the wells within Minden Town are below that limit, there is one (Well 7) that is above the EPA’s threshold or maximum contaminant level (MCL). Other wells within Carson Valley have tested higher and have been taken out of service or required treatment for continued use. The arsenic levels in the wells around the valley have varying concentration and tend to fluctuate over time. Due to the concern about increasing arsenic levels in Minden’s wells, this study was commissioned to identify potential wells that would need treatment or mitigation. The goal is to provide enough background data for the Town to be able to identify when mitigation might be required as well as to provide a roadmap to determine the best mitigation strategy for the Town. In this report, we discuss the research that has been completed, different treatment or mitigation options, the estimated costs to implement each mitigation option, and a decision matrix to determine the best mitigation solution for the Town. There are many options when it comes to treating and removing arsenic from water. Some options include building a treatment facility and selecting treatment equipment to remove the arsenic, while a simpler solution is to blend the arsenic laden water with water that has a lower concentration of arsenic to produce a combined water stream whose total arsenic concentration is below the MCL or the target level determined appropriate for the Minden Town’s system. The cost to implement these different solutions will need to be planned for and funding sources identified to help pay for the cost of implementation. Currently, the arsenic levels in Minden’s water wells seem to be trending toward lower concentrations. This, however, may change over time and proper mitigation strategies must be in place along with financial, and other resources to be able to quickly mitigate high arsenic levels when the need arises. We investigated several mitigation options including, pre-distribution blending, source abandonment and replacement, source reconfiguration, and treatment options. For the treatment options we looked at coagulation/filtration, enhanced lime softening, reverse osmosis (RO), ion exchange (IX), activated alumina (AA), iron-based sorbents, and ultrafiltration. Several key areas were scored for each option to give a sense of which option best meets the needs of Minden Town. The best option was found to be pre-distribution blending. It was identified that blending Wells 5 and 11 together and Wells 2 and 3 together were the best options for blending to keep the arsenic ---PAGE BREAK--- 2 concentrations below the target limit of 7 ppb. This is the lowest overall cost, both initial capital costs as well as ongoing maintenance costs. By piping two wells together in a common location the combined flow can have lower total arsenic. Additionally, by doing this first the infrastructure is already in place should further treatment be required down the road. When the Town needs to add additional capacity to the system it is recommended to pipe Wells 7, 8, and 9 together near Well 9 and provide treatment in that location. Assuming the full flow from each of those three wells, the combined arsenic concentration would be 8.41 ppb. While this is above the target of 7 ppb, it is still below the EPA mandated limit of 10 ppb. To get the combined flow’ arsenic concentration below 7 ppb, treatment would be required. Of the treatment options included in this study, ultrafiltration was identified as the best solution. It has the advantage of a lower footprint and relatively low costs. At the treatment location for Wells 7, 8, and 9 only side-stream treatment would be required. It is estimated that only about 900-1000 gpm would be required to be treated of the 4,100 gpm total that would be combined at that location. It will be critical for the Town to monitor each well’s arsenic levels on an ongoing basis. We recommend monitoring should be at least semi-annually. Arsenic levels should be recorded and trends noted to determine if further mitigation will be required. ---PAGE BREAK--- 7/20/2020 3 Literature Review Background Information Arsenic is a naturally occurring chemical element that is found in many drinking water wells. Arsenic is often found in combination with sulfur and other metals in water. When water passes through the ground where arsenic is present, some of the arsenic is dissolved into solution. The arsenic in water is typically found in one of two forms or speciations, AS-III (arsenite) which is a reduced form of arsenic and AS-V (arsenate) which is an oxidized form of arsenic. AS-III is more mobile in water and is more difficult to remove, requiring additional steps in the treatment process to oxidize it to the AS-V form for removal. AS-III is a negatively charged ion that does not attract other metals, whereas AS-V is positively charged and is attracted to negatively charged particles such as iron. Since the AS-III will not attract to other ions or particles it stays in solution and can move through an aquifer more freely than the AS-V ions. The US Environmental Protection Agency (EPA) adopted a new standard for arsenic in drinking water on January 22, 2001. This new standard lowered the old limit from 0.05 mg/L to 0.01 mg/L (50 parts per billion (ppb) to 10 ppb). This limit is called the maximum contaminant level or MCL. All water systems had to meet this new MCL by January 23, 2006, once the new rule was formalized. There were some additional discussions on the cost to implement this rule and the original effective date was postponed until February 22, 2002, but the new 0.01 mg/L limit remained in place. The EPA and Nevada Division of Environmental Protection (NDEP) require sampling at each entry point to the distribution system. This ensures that each source of water being used in a system is monitored and provides multiple samples to understand the entire system. Samples should be taken quarterly (and in some cases to analyze the contaminant level. A running annual average concentration is calculated based on the sample analysis. Systems are deemed in compliance with the rule if the running annual average is below the MCL (i.e. <0.01 mg/L for arsenic). Minden Town’s Water System and Arsenic History Minden Town is located in Douglas County, Nevada. The Town is situated approximately 15 miles south of Carson City along U.S. Highway 395. The valley is supplied with water from the Sierra Nevada, Carson, and Pine Nut mountain ranges’ snowmelt which flows into the Carson River as well as into the ground forming an underground aquifer. Groundwater around Minden flows generally from the east toward the East Fork and Carson River (Yager et al 2012). Minden Town has nine wells as part of its water system. The Town currently uses eight of the nine wells. Well #7 is high in arsenic and is not currently in use. The wells that are in service provide the Town with a source capacity of 14,250 gallons per minute (gpm). Well #7 has a rated capacity of 1,250 gpm which if treated, could be added to the system as an additional source. The Town doesn’t currently have any treatment in their system, except for chlorination at the Heybourne booster station building. Water flowing through the booster station is chlorinated before being sent to wholesale water customers. The chlorination is achieved by dosing sodium hypochlorite into the water. The sodium hypochlorite is delivered to the booster station in bulk rather than being generated on-site. ---PAGE BREAK--- 4 Previous Arsenic Research Due to high arsenic in the groundwater in the Carson Valley, Carson City has had to discontinue using several of their wells which have arsenic levels above the MCL. Because of this, Carson City now purchases water from Minden Town. Minden supplies water to several surrounding communities in addition to providing drinking water to the Town’s residents. Minden currently supplies wholesale water to Douglas County, Indian Hills GID, and Carson City. In addition to the water rights owned by the Town of Minden, additional water rights have points of diversion being wells operated by the Town of Minden. These water rights aids in providing wholesale water. Because of the elevated levels of arsenic in some of the wells, there is growing concern about what to do if the arsenic levels exceed the MCL. With one well, Well testing above the MCL and others just below the MCL the Town has initiated this study to develop a plan for mitigation. Figure 1 shows Minden’s wells and their respective arsenic levels. Note that Well #7 is currently the only well that has exceeded the arsenic MCL. During this study, there has been considerable discussion and evaluation of different data sets showing arsenic levels at different testing locations throughout the distribution system. The final data set used consists of the average arsenic values tested at each well. This data was provided to Sunrise by Minden Town. It is important to note that some wells have much more testing data than others. Going forward, well testing should be done on a semi-annual basis and trends should be monitored. Samples should be taken from each well on the same day to ensure proper comparison. Since the average was used for this report, it will be important to note any trends that may make the average less accurate going forward. If wells all test high on the same day or all test low on the same day, the randomness of the average might not be appropriate. Figure 1-Minden Town Well's Arsenic Levels ---PAGE BREAK--- 5 The U.S. Geological Survey (USGS) has studied arsenic in groundwater in Carson Valley to try to understand what is causing increasing arsenic levels in the aquifer and where the higher concentrations of arsenic are. They have also done some research to identify possible mitigation efforts that could be used to reduce the arsenic concentrations in the water. During their studies, they were able to get an understanding of the water and where the different forms of arsenic are found in the water. The point where arsenic changes from AS-III to AS-V is called the Redox boundary. This boundary location is not an exact point or elevation, but some generalization can be made that water above a certain level in the aquifer will have predominantly higher levels of AS-V, and water below a different elevation will contain more AS-III (see Figure In one test near the Douglas County Airport, they were able to create a model that shows that the deeper the well, the more arsenite (AS-III) was present, and in the upper levels of the aquifer more oxygenated water is present and the predominant form of arsenic is arsenate (AS-V). Figure 2, from the USGS report (below), shows the aquifer model and where the different speciations of arsenic are found. Figure 2-Carson Valley Aquifer Model (USGS) Knowing the speciation of arsenic in water can provide some guidance when it comes to treating the water. Some treatment technologies can only remove AS-V from water (see treatment section later in this report). In these cases, the AS-III must first be oxidized to AS-V. Additionally, it is important to know how much of each form of arsenic is in the water. If there is enough AS-V already in the water, treatment may only be needed to remove that portion of the arsenic to bring the water into compliance with the MCL rule. USGS also did some testing to understand if in-situ treatment would be a feasible option. There were two phases of testing. The first phase was using a single well to pull the water from the ground, chemically condition the water and re-inject it back into the ground. The second phase used a three well set-up to treat the water. The in-situ treatment that was tested involved pumping well water to the surface, aerating the water, oxidizing the AS-III to AS-V using sodium hypochlorite, removing free chlorine through activated carbon filters, adjusting the pH, injecting ferrous chloride, and reinjecting the water into the aquifer. The treated water was pumped either from the same well in phase one or from a ---PAGE BREAK--- 6 nearby well in phase two at a similar rate to the water being injected. The treated water was consistently below the MCL for arsenic. In the first set of experiments, there was high iron in the treated water at points above the secondary MCL for iron. The second round of in-situ tests performed by USGS showed some promising results for in-situ treatment. The challenge was getting enough air into the aquifer. This treatment technique was shown to be a possible solution. The costs would need to be evaluated to determine how this treatment compares with other treatment technologies. There would still be a waste stream from this treatment technique as the activated carbon filters would need to periodically backwash and the media, once spent, would need to be either regenerated or replaced. Some of the key conclusions from the USGS study include 1. Limited arsenic concentration data are available within the past 10 years from areas surrounding Minden. 2. Different wells have differing predominant forms of arsenic. 3. Based on the data evaluated as part of the USGS study, higher concentrations of arsenic are found in water from deeper wells. 4. In-situ treatment could work. Using a three well system was better than the single well system. 5. In some areas, arsenic concentrations responded to varying pumping rates. When one particular well was pumped at a higher rate, the arsenic concentration was above the MCL, but when it was pumped at a slower rate, the arsenic concentration was below the MCL. As we have reviewed the data, we have noted that there are variations in arsenic levels over time. The last several years of data from Minden Town (Figure 3 below) show a downward trend in arsenic levels on average, but there are local highs and lows. Well 7 is the only well that has an upward trend. The solid lines represent the well testing data, and the dotted lines are linear trendlines indicating if the arsenic levels are increasing or decreasing over time. The full data set for this chart is included in Appendix 5. Note that some wells have many data points while others just have a few. The data from USGS has some testing locations’ arsenic levels increasing over time and others decreasing and some remaining fairly consistent. All the arsenic data that we could find from Minden Town and USGS were plotted on a map showing where the higher and lower concentrations of arsenic are found within the valley. The map is included in Appendix 1. Note that areas north toward Carson City generally show high levels of concentration, while areas further to the south near Gardnerville and Gardnerville Ranchos show lower concentrations. The data do not show the depths of the wells, so there may be some additional information to be learned if the well depths were plotted similarly. The scope of this study was to determine mitigation strategies for Minden Town should arsenic levels rise. There is much more research that could be done to study historical information and try to predict future arsenic levels. Study topics could include the effect of water age on the arsenic levels in the aquifer, the effects of wet or dry years on arsenic levels in the aquifer, or myriad other topics that could be studied to gain a better understanding of the aquifer and what the major influencers of arsenic concentrations are. Based on the data we have, it is our opinion that there is a low risk that the arsenic level in Minden Town’s wells will increase enough to require treatment in the near future. The remainder of this report will focus on arsenic mitigation strategies and layout a plan for Minden Town to address rising arsenic levels should they increase to a level requiring treatment. ---PAGE BREAK--- 7 Figure 3-Minden Town Arsenic Trends ---PAGE BREAK--- 7/20/2020 8 Mitigation Strategies There are several different ways to mitigate arsenic in the drinking water supply. We started this study with the idea that all options are on the table and therefore we will discuss the mitigation options that could be feasible for Minden Town’s water system. It is important to note that since Minden is a wholesale water supplier to other water companies, we have to take into account the other system’s requirements. For example, Carson City blends Minden water into their water to effectively reduce the arsenic in their supply water. Therefore, the real target for treatment is to keep Minden’s water at or below 7 ppb arsenic. While this is below the EPA mandated MCL, the limit of 7.0 was decided upon with all stakeholders as a reasonable limit to ensure safe water for each party involved. When evaluating arsenic mitigation or treatment options, it is important to understand how the arsenic levels are determined. According to the EPA, the MCL is measured against a running annual average arsenic concentration entering the system (CRAA). The formula used to determine compliance with the rule is: ܥଵ+ ܥଶ+ ܥଷ+ ܥସ 4 Where: CRAA = Running Annual Average Arsenic Concentration Entering System, C1 = Arsenic Concentration Entering System During the 1st Quarter, C2 = Arsenic Concentration Entering System During the 2nd Quarter, C3 = Arsenic Concentration Entering System During the 3rd Quarter, C4 = Arsenic Concentration Entering System During the 4th Quarter. In Nevada, NAC 445A.454.4.b requires testing and the running annual average is calculated each month using the last twelve months’ data. Understanding this equation and understanding the water supply characteristics can help determine which mitigation strategy makes the most sense. The mitigation options evaluated as part of this study are: 1. Pre-distribution blending 2. Source abandonment/replacement 3. Source reconfiguration/seasonal or limited use 4. Point of use treatment 5. Treatment (or side-stream treatment) a. Coagulation/Filtration b. Enhanced Lime Softening c. Reverse Osmosis (RO) d. Ion Exchange e. Activated Alumina f. Iron-based Sorbents g. Ultrafiltration Some of these options were quickly identified as less effective or impractical for the Town, while other options were investigated in more detail. Below is a discussion of each mitigation or treatment option and why it was or was not selected as a viable option for mitigation. ---PAGE BREAK--- 9 Pre-Distribution Blending The idea behind pre-distribution blending is that if two or more water supplies have differing levels of a contaminant such as arsenic, you can blend the water prior to introducing it into the distribution system. By doing this you can effectively lower the overall concentration of the contaminant if one or more sources are initially below the MCL. By doing this, it may be possible to eliminate the need for treatment. There is still a cost associated with this method. The two sources are, in most cases, not usually located close enough to make this work effectively. Some system changes are usually required in order to be able to get the two sources to blend before entering the system. When blending multiple sources, it is important to have accurate flow measurements on each source to ensure that the sources are being blended at a ratio that will produce an arsenic concentration that meets the desired level below the MCL requirement. The figure below from the EPA’s Arsenic Treatment Technology Evaluation Handbook for Small Systems shows a schematic of blending two wells. Figure 4-Blending (EPA) The equation below can be used to calculate the ratio of each source and the final arsenic concentration. ܳଵ∗ܥ஺௦,ଵ+ ܳଶ∗ܥ஺௦,ଶ ܳଶ Where: CAs,B = Arsenic Concentration of Blended Stream (mg/L), CAs,1 = Arsenic Concentration of Well 1 (mg/L), CAs,2 = Arsenic Concentration of Well 2 (mg/L), Q1 = Flow Rate of Well 1 (gpm), Q2 = Flow Rate of Well 2 (gpm). In the Minden Town water system, there are a few wells that are located relatively close to each other and could be piped together to provide pre-distribution blending. Wells 2 and 3 are close and could easily be piped together. Wells 5, and 11 could all be combined at well 11 and blended and then put into ---PAGE BREAK--- 10 the distribution system at that point. Wells 7, 8, and 9 are all close together as well. Some piping would need to be added to make blending work. A preliminary review of Minden Town’s water distribution model indicates that piping these wells together and then introducing the combined flow into the system at a common location has very little effect on the system pressures and flow capacities throughout the distribution system. Five blending scenarios were investigated. These scenarios were selected due to the proximity of wells in certain locations. Scenario 1 looked at piping Well 2 and Well 11 together to blend their water. Scenario 2 added Well 5 into scenario 1. Scenario 3 was to blend Well 2 with Well 3. Scenario 4 was to blend water from Wells 7 and 8 together. Scenario 5 was the same as Scenario 3, but with the addition of Well 9. A discussion of the costs and infrastructure to do this is included later in this report. Scenario 1 – Well 2 is currently the third-highest arsenic concentration well in service in Minden Town. Well 2’s average arsenic level is 7.9 ppb and the well has a pumping capacity of 2,400 gpm. If the full flow of Well 2 were to be combined with Well 11 (1,700 gpm and AS=4 ppb) the total arsenic of the blended water would be 6.28 ppb. By doing this, the water would be below the target of 7 ppb with limited additional infrastructure. Scenario 2 – Well 5 has a current capacity of 1450 gpm and an average arsenic concentration of 7.8 ppb. If the arsenic in wells 2, 5, or 11 went up any higher Well 5 could be blended with these other two wells to still be able to use the full design flow of each well and keep the arsenic concentration below the target level of 7 ppb. Based on the average arsenic levels currently measured, blending all three of these wells would produce a combined arsenic concentration of 6.68 ppb. Scenario 3 – A second option to help lower the arsenic concentration in Well 2 would be to blend it with Well 3. Well 2 has an average arsenic concentration of 7.9 ppb and a flow rate of 2400 gpm. Well 3 has an average arsenic concentration of 4.4 ppb and a flow rate of 2000 gpm. If the full flow of each well was blended together the combined arsenic concentration would be 6.31 ppb. This is below the Town’s target of 7 ppb and would not require any further treatment. Scenario 4 – Currently Well 7 is not being utilized by the Town but is designated as an emergency backup well. Its primary function today is to ensure fire flow can be met if needed but is valved off and kept out of service most of the time. Well 7 has an average arsenic concentration of 10.3 ppb. Well 8 has been reported to have a high arsenic concentration at startup in the springtime, but as it is consistently pumped, the concentration falls below the MCL and settles between 6-9 ppb. Based on the data used for this study, the average arsenic concentration for Well 8 is 8.5 ppb. Depending on where the arsenic concentration in Well 8 settles, blending might be an option. Based on the average arsenic levels of Wells 7 and 8 and using each well’s full flow the total combined arsenic level would be below the MCL of 10 ppb but would be higher than the target of 7 ppb and is calculated to be 9.46 ppb. By using Well 7, the Town could increase its source capacity if needed. Scenario 5 – Well 9 has a capacity of 1750 gpm and an average arsenic concentration of about 7 ppb. If wells 7, 8, and 9 were all combined at their maximum flow rates and assuming well 8 had an arsenic concentration of 8.5 ppb, the combined blended arsenic concentration would be 8.41 ppb. While this is above the target of 7.0 ppb, this could be a feasible option, especially since Well 7 is not needed to meet current demand. As demand increases, Well 7 could be blended at a lower flow rate to keep the total concentration closer to the target limit while increasing the Town’s source capacity. ---PAGE BREAK--- 11 In order to achieve proper blending, there would need to be some level of control to be able to manage the flow from each well. It would be critical to ensure that the ratio of water from each well was blended at the appropriate level. As arsenic levels change, the controls will need to be updated to reflect the new levels and adjust the blending ratios accordingly. This could be programmed to be as simple as having the operator enter the latest arsenic number into a control system (PLC/HMI/SCADA) and have the system automatically adjust the flow rates to keep the total concentration below the target. Depending on how the arsenic levels change over time, blending may not be a permanent solution. With Well 7 already very high, it will be difficult to use that water if the arsenic levels in Well 8 or Well 9 increase much. This is especially difficult to anticipate when the levels might change and make blending ineffective. Source Abandonment and Replacement Source abandonment and replacement is one option for arsenic mitigation. The idea is to try to locate a new water source or well where the water can meet both the flow and contaminant concentration requirements. The challenge with using this mitigation option is that all the wells in the surrounding area draw from the same aquifer which has consistently high arsenic concentration levels throughout. There does appear to be an area of lower arsenic concentration near the Gardnerville area. If a new well were to be investigated, this area should be investigated further. As we have discussed this option with Minden, they don’t feel that there any feasible new well development sites that will give better water quality than what they have now. The Town needs all of its current wells (minus Well 7) to meet peak demands, therefore source abandonment is not an option. There are additional water rights issues with developing a new well if that option were to be pursued. Source Reconfiguration/Seasonal or Limited Use As was presented earlier in this section, the arsenic levels are only considered as exceeding the limit if the running annual average is above the MCL. Therefore, it is possible to only use high arsenic wells during the peak demand months and let the arsenic levels exceed the MCL limit for a few months out of the year. By doing this it is possible to keep the running annual average arsenic concentration entering the system below the target limit. To illustrate this idea imagine a well has an arsenic concentration of 15 ppb and it is used for four months out of the year. The other eight months it is not used. Therefore the arsenic concentrations introduced into the distribution system would be 0, 0, 0, 0, 15, 15, 15, 15, 0, 0, 0, 0 ppb. This would mean that the 12-month rolling average would be (15*4+0*8)/12 = 5 ppb. Though this method meets the rule requirements, it may not be desirable for the drinking water system. Having to explain this to the public may cause concern and present problems with public perception. While this method can be employed on an as-needed basis, we wouldn’t recommend this as a permanent solution. Treatment There are many different treatment options. Several factors need to be accounted for when deciding if treatment is the right option, and if so, which treatment technology is the best fit for the situation. When looking at treating water with arsenic it is critical to know what other constituents are in the water. Silica, chloride, fluoride, manganese, and other contaminants in the water at sufficient levels can interfere with some of the treatment processes. It is also important to know the speciation of arsenic in ---PAGE BREAK--- 12 the water. Some treatment technologies can only remove AS-V from the water. If the predominant species of arsenic is AS-III, provisions need to be put in place to convert the AS-III to AS-V. Also, depending on the concentrations of each valent state of arsenic in the water, treatment may only be needed to remove the easier-to-remove AS-V. Provisions should always be made for future changes in the speciation so that in the future AS-III could also be removed with minimal changes to the treatment process. A few key considerations when thinking about treatment options are, · Land availability for treatment equipment or a treatment plant. · The distance between wells to be treated. · The possibility of a central treatment facility. · Operator availability and qualifications. If there are multiple sites with treatment, how is an operator going to manage multiple sites? The costs of treatment can be significant; not only the capital costs but, the ongoing operation and maintenance costs can make a treatment option impractical. Additionally, water losses will need to be accounted for in the decision-making process. Some treatment technologies like RO can have high water losses. Some RO processes can waste up to 50% of the incoming water. All treatment options have some sort of waste stream, whether that be a liquid waste stream, or a solid waste stream, such as spent media. Waste disposal could be a deciding factor between treatment options due to the costs of disposal and the complexity of handling the waste. Some waste streams may be hazardous, depending on the concentration of arsenic and its potential to leach out of the waste. When evaluating each treatment type, we will discuss the waste stream and typical means of disposal. Arsenic treatment can either be done on the entire flow from a well or just a portion of the water and blend the treated water with the untreated water as described above. This is called sidestream treatment. This can be done in several ways. Depending on the level of arsenic in the water and the desired total arsenic level after treatment, a part of the flow from a well could be treated and blended back into the rest of the flow to achieve an appropriate level of reduction. Similarly, one well may be treated and then blended with an untreated well to achieve a total arsenic level that is below the target arsenic level. The EPA handbook - Arsenic Treatment Technology Evaluation Handbook for Small Systems, gives a great example of how to calculate how much water needs to be treated through a sidestream process. The equation and figure below are from the EPA’s handbook. ---PAGE BREAK--- 13 Figure 5-Sidestream Treatment ܳଵቆ ܥଵ−(1 ܥଵ[1 ቇ Where: QS = Flowrate to Split Off for Treatment (gpm) QB = Flowrate of the Final Blended Stream (gpm) Q1 = Source 1 Flowrate (gpm) C1 = Arsenic Concentration of the Source (mg/L) CMCL = Arsenic MCL (mg/L) s= Safety Margin expressed as a decimal) w= Treatment Water Loss expressed as a decimal) e= Arsenic Rejection Rate expressed as a decimal) By limiting the amount of water that is needed to be treated, costs can be kept to a minimum. Less infrastructure will be required to create a workable system that meets the target arsenic limits. Pre-Oxidation Processes For the best treatment results, a pre-oxidation step must be completed to convert the inorganic AS-III to AS-V. This will facilitate better removal. All treatment options described in this report, with the possible exception of RO, require pre-oxidation. Introducing an oxidizing agent into the water ahead of any treatment process will convert arsenite (AS-III) to arsenate (AS-V). Chlorine, permanganate, ozone, and some solid phase oxidants are most commonly used to accomplish this. It is important to note that chlorine dioxide and monochloramine are ineffective oxidizing agents for arsenic. UV is a disinfectant, but it will not oxidize arsenic. Each of the oxidizing agents has its benefits and drawbacks. It is important to fully understand the pros and cons of each when deciding which oxidant to employ in a system. Some treatment technologies work better with certain oxidants while others are better suited for different treatment technologies. Since many treatment systems use chlorine as a disinfectant, it is possible to use existing chlorine systems to provide AS-III oxidation. ---PAGE BREAK--- 14 Chlorine and permanganate behave similarly when oxidizing AS-III. The theoretical or stoichiometric oxidant demand is 0.95 and 1.06 mg per mg of AS-III for chlorine and permanganate, respectively. Typical doses in stoichiometric excess of three times is usually sufficient to oxidize 95% of the AS-III to AS-V. The pH levels that are recommended are between 6-8. Both permanganate and chlorine will preferentially oxidize sulfide. Sulfide above 1 mg/L typically slows the oxidation reaction. Chlorine can be dosed as a gas or a liquid as hypochlorite. There are inherent risks when handling chlorine and careful attention must be paid to keep operators safe. Small systems can generate hypochlorite on-site, or have it delivered commercially. Chlorine gas typically is delivered in 150 lb. canisters. Another challenge with chlorine is the potential to form disinfection by-products (DBPs). System modeling and testing are recommended to try to determine DBP formation potential and make sure the system will remain compliant with the DBP rule. Permanganate is typically used when also oxidizing iron and manganese. Potassium permanganate can be found in a solid, granular form that can easily be dissolved into water and metered into the process stream. Permanganate is also difficult to handle. Often it comes in a powder which is very corrosive and gets all over everything. Permanganate is purple in color and stains most things it touches. If dosed in too high a rate, it can turn the water purple leading to concerns and complaints from customers. Additionally, permanganate is not used as a secondary disinfectant, therefore another oxidant may be required in the system. Ozone is another common oxidant. It is very effective and efficient at oxidizing arsenite to arsenate. Ozone is the most powerful and fast-acting oxidizer. Ozone is made by exposing oxygen to a high energy source or UV radiation. This causes the oxygen molecules to react and form an unstable configuration of three oxygen atoms – the oxygen molecule contains only two (EPA Arsenic Treatment Technology Handbook). The ozone molecules are quite unstable and must be produced on-site as they degrade and revert to regular oxygen (O2) molecules rapidly. This means that if ozone is used, it must be generated on-site. One advantage is that ozone’s only byproduct is oxygen which naturally dissolves in water and is harmless. The stoichiometric oxidant demand for ozone is 0.64 mg of ozone per mg of AS-III. Typical ozone dose rates are the same as chlorine or permanganate at a stoichiometric excess of three times. Sulfide concentrations above 1 mg/L did slow the oxidation reaction and must be accounted for in the treatment process. Ozone also doesn’t provide a secondary disinfectant, and therefore another disinfectant must be used when disinfection is required. Some proprietary solid phase oxidants generally consist of a manganese dioxide material that can be used to catalyze the oxidation of arsenite to arsenate. These oxidants rely on dissolved oxygen in the water and catalytically oxidize the AS-III to AS-V. Some of these media also tend to adsorb some of the arsenic. When all the area of the media has been expended by adsorbing compounds the media is spent and must be replaced. These oxidants rely on dissolved oxygen in the water and therefore if the water to be treated has low dissolved oxygen, this process may not be suitable. Typically, as the pH decreases to around 6, the removal becomes more effective. Iron, manganese, hydrogen sulfide, and total organic carbon (TOC) tend to interfere with the oxidation reaction, especially when the DO concentration is low. To overcome this, the DO concentration needs to be increased, or the empty bed contact time (EBCT) must be increased significantly. ---PAGE BREAK--- 15 Point of Use Treatment Point of use (POU) treatment is a method of treating arsenic laden water at each point of use. When this method is used, the public utility must own or contract directly with the owner of the devices. This means that the utility is ultimately responsible for operating and maintaining the treatment devices to ensure proper function. There are many different POU treatment options. One challenge, though, is that they don’t address pre- oxidation. In many cases, a water utility must chlorinate the water at a central location or at each source to convert the AS-III to AS-V. Typical POU treatment technologies include activated alumina, iron-based sorbents, and reverse osmosis. POU treatment is advantageous in that only the fraction of water meant for consumption is required to be treated. Typically, POU treatments are installed underneath a kitchen sink and have a separate faucet. Doing this typically has lower initial costs, but the administration costs are higher than centralized treatment. In most situations, POU treatment is only cost-effective for systems serving less than 500 people, and typically even fewer connections. The next section of this report will go into details of each treatment option and discuss the advantages and disadvantages of each option. We will discuss ancillary equipment that would be required with each treatment option as well. ---PAGE BREAK--- 7/20/2020 16 Treatment Processes Several treatment technologies were evaluated and are discussed in this section. We have assumed two flow rates for treatment that would cover most wells in Minden Town. It is understood that side stream treatment is a possibility and would most likely be used in Minden, however, we have investigated sizing and pricing for treating an entire well’s production flow. This is a worst-case scenario and will give an equal ground for evaluating the treatment technologies. Two treatment plant locations have been proposed and would require the Town to acquire property for the plants. Coagulation/Filtration Arsenic in water is found in very small colloidal particles that typically don’t filter out readily. For this process, steps must be taken to condition the particles so they form larger grains that can be captured in a filter. This is called coagulation and agglomeration. Coagulation is accomplished by destabilizing surface charges of the colloidal particles and allowing them to agglomerate to form larger stable floc that can be filtered. This is typically done using coagulants such as aluminum (alum) and iron (ferric) salts. Arsenic in the form of arsenite must first be converted to arsenate for it to coagulate. Arsenate has an ionic charge that allows it to co-precipitate onto the iron added to the water. This process is typically done through adding an oxidant and then the coagulant. The water is typically then mixed via a static mixer and then fed into a large pressure vessel that has a filter media to trap the coagulated particles and allow the clean water to pass through. Once the media bed becomes plugged with trapped particles, a backwash is required to remove the contaminants. This is done by reversing the flow. Commonly an air scour step is provided either in combination with the water backwash or as a separate step. The air scour helps to minimize the required backwash flow rate and provide a more aggressive cleaning which tends to extend filter run times. Several types of media can be used to filter out coagulated particles, but the most common is silica sand and anthracite. Depending on water quality and what constituents are in the water, media depths and sizes will vary to produce an effective solution without causing undue headloss from excessive media depths or too small media particle sizes. Pressure filters can be used in either a vertical or horizontal configuration based on application and flow rate. For the two flow rates investigated for this study, 2000 gpm and 1200 gpm, horizontal pressure filters make the most sense. The design allows for three filter cells per vessel. The media recommended for Minden Town is a single media type consisting of 24-inches of silica sand 0.45-0.55 mm effective size. The loading rate recommended is 2.9 gpm/ft2. Having three cells in each filter allows the backwash water to be generated from the two filters in service and putting most of the flow out as backwash wastewater. For the 1,200 gpm system, the backwash flow is 517 gpm with an air scour rate of 138 scfm. For the 2,000 gpm system, the backwash flow is 865 gpm and an air scour rate of 230 scfm. The filters’ footprint is approximately 22’ x 30’ x 13’ for the 1200 gpm system and 36’ x 30’ x 14’ for the 2,000 gpm system. These filters can be placed outside, but for the climate in Minden, it is recommended that they are placed inside a building to keep them from freezing. ---PAGE BREAK--- 17 Enhanced Lime Softening Enhanced Lime Softening is a potential option for treatment, but it is not typically economical for small distributed systems that have sources spread out such as in Minden, and especially it is not a great option if the water doesn’t need softening independent of the arsenic treatment. Lime softening is a precipitative process that is typically used to remove calcium and magnesium from water. This process involves adding lime and sometimes soda ash to the water. By adding these chemicals the pH of the solution increases to 10.5 or above forming magnesium hydroxide. Arsenate will co-precipitate with the magnesium and then can be settled via traditional clarification. The removal efficiency for arsenic is typically lower than other treatment options. To be able to remove arsenic with lime softening, there needs to be an excess of magnesium and lime in the water. The arsenite must also be converted to arsenate before the lime softening process. Additionally, after the lime softening step, it is typically required to re-carbonate the water and lower the pH back to the neutral range. Lime softening systems typically consist of solids contact clarifiers which take up a large footprint. The sludge that is produced contains all of the removed arsenic and typically requires further dewatering or treatment prior to disposal. For all of these reasons, it is not recommended to use Lime Softening for Minden. Reverse Osmosis (RO) RO involves forcing water through a membrane with microscopic holes designed to allow pressurized water molecules through but prevent the penetration of up to 95% of As-V molecules as well as other harmful inorganic chemicals such as manganese, chromium, and lead. For Minden, the RO process would consist of large tubes, horizontal to the ground, where the water and constituents are separated before the clean water is sent to a tank for storage. RO is sometimes accused of cleaning water too much, as almost everything is completely removed from the water. The complete removal of ions is generally a plus, but a pH adjustment and returning minerals to the water are generally needed to counter resulting health and taste issues. In order to ensure proper sizing and operation, we will need to perform a current analysis of as many constituents as possible to understand any pretreatment requirements. The constituents of interest for RO are Calcium, Bicarbonate, Silica, Magnesium, Chloride, Phosphate, Sodium, Sulfate, Total Dissolved Solids, Potassium, Nitrate, Total Suspended Solids, Barium, Fluoride, Turbidity, Strontium, Bromide, pH, Ammonia, Boron, Temperature, and Iron. One Equipment supplier, WesTech Engineering, has offered two separate RO designs for this specific project. The first system design consists of one RO filtration unit sized to treat a gross influent flow of 1,200 gpm. The unit is designed as a single-pass, two-stage system in a 17:8 7M configuration with 175 elements installed. The second system design consists of two membrane filtration units each sized to treat a gross influent flow of 1,000 gpm for an overall treatment capacity of 2,000 gpm (See Figure 6, below). The units are designed as a single-pass, two-stage system in a 14:7 7M configuration with a total of 294 elements installed. The overall system recovery for both is targeted at 75%. See “WesTech RO Detailed Design Summary,” “WesTech RO scope of supply” and “WesTech RO Clean in place system” in Appendix 2. Pre-oxidation and precipitation of arsenic will be needed. ---PAGE BREAK--- 18 Figure 6 - WesTech Reverse Osmosis System Rated for 2,000 gpm Capacity Some of the of RO are ease of installation and operation, a small footprint, ease of expansion, and long term reliability. It requires no addition of chemicals to treat for arsenic, however, if large concentrations of AS-III are present in the water oxidation will be required. RO typically removes less than about 70% of AS-III without pre-oxidation. Removal of AS-V is much better typically >90%. Though the system is more complex than other treatment systems, RO controls are fully automated and allow for remote monitoring and operation if desired. The main downsides to RO treatment are the byproduct and efficiency. The byproduct is brackish water with higher levels of arsenic that may be difficult to dispose of. At best, 25% of the water undergoing RO is lost and must be disposed of properly. RO requires high pressures estimated at 170 PSIG. Oxidation is often required before RO if the majority of the arsenic needing to be removed is in the As-III form. To fully understand how an RO system would operate and to determine the actual recovery and efficiency a full water quality analysis would need to be done. The specific constituents important to RO performance are, · Calcium (Ca) · Magnesium (Mg) · Sodium (Na) · Potassium · Barium (Ba) · Strontium (Sr) · Ammonia (NH4) · Iron (Fe) · Bicarbonate (HCO3) · Chloride (Cl) · Sulfate (So4) · Nitrate (NO3) · Fluoride · Bromide (Br) · Boron · Silica (SiO2) · Phosphate (PO4) · TDS (mg/L) · TSS (mg/L) · Turbidity (NTU) · pH · Temperature ---PAGE BREAK--- 19 Reverse Osmosis systems do require more energy to operate than most other systems discussed in this report. This is due to the high operating pressure as well as the need for compressed air to aid in the cleaning. The addition of pumps and an air compressor require additional maintenance as well. RO systems also require intermittent chemical cleanings. The chemical cleaning procedure utilized by RO treatment systems is called a Clean-in-Place (CIP) procedure. This is automated and requires little operator interference to initiate or operate the cleaning process. The CIP typically utilizes either sodium hydroxide or hydrochloric acid. Different triggers initiate a CIP each of which is monitored by the control system. Depending on the system setup and wastewater disposal requirements, the CIP waste may need to be captured and neutralized before disposal. Ion Exchange The Ion Exchange (IX) process most often involves the influent entering a large tank full of physical media. The media often refers to small glasslike beads with a specific chemical makeup that attracts the molecules needing to be removed (in this case, the media is specifically engineered to attract arsenic). The water enters the top portion of the first media filled tank, then leaves through the bottom and enters the top of the second tank. The water runs swiftly through the media, passing close enough to thousands of beads that almost magnetically remove the arsenic molecules, then continues on its way. The two tanks provide redundancy, for the potential time needed to replace media in the first tank after the media is spent or “inundated” with arsenic. The media removal is easily done by opening a This process is very safe, as no extra chemicals or other items are needed to be stockpiled or added to the water. The media is easily removed after it has been spent, or “inundated” with arsenic. The media can then be taken to a facility where it is cleaned and regenerated before it is returned to the site for reuse. In some cases, the spent media is used only once and then landfilled. Care must be taken to ensure that the toxicity of the spent media is monitored so that proper disposal will occur. The constituents of interest are typically vanadium, total hardness, temperature, alkalinity, silica, phosphate, total dissolved solids (TDS), nitrate, total suspended solids (TSS), molybdate, antimony, selenium, uranium, and pH. Purolite has developed a resin called FerrIX which works well in a pH range of 4.5 to 8.5. The FerrIX method touts high reliability, as well as a very low pressure drop as the water passes through the vessels. As long as total Arsenic is less than 2000 ppb, Vanadium is less than 100 ppb, Phosphate is less than 1 mg/L, and silica is below 90 ppb, pH is between 6 and 9, the temperature is less than 176° F, Nitrate is less than 5 ppm, and other oxyanions are less than 50 ppm, it will work efficiently (see “Purolite, FerrIX Physical and chemical characteristics.” To obtain more specific details about Minden using FerrIX, additional testing will need to be performed on the current well water. Exact measurements for a system haven’t been made, but given the similarities to Granular Ferric Hydroxide (GFH, described later), the system will likely require a similar amount of space. Ion exchange generally costs more than other treatment methods. The resin needs to be replaced periodically and depending on the total amount of arsenic in the media it may be classified as hazardous waste. Testing can be completed to determine the time between media replacements. Also, Vanadium, Phosphate, Silica, nitrate, and a pH far from 7, will interfere with treatment. A typical treatment train consists of two tanks with media. The water enters the first tank at the top and flows down through the media and is collected at the bottom of the tank. The water then is directed to the top of the second tank and again flows down through the media where it is again collected at the ---PAGE BREAK--- 20 bottom of the second tank. There is piping and valving between the two tanks to allow the direction to be reversed so that the second tank can become the first tank. This way when the media is fully spent in the first tank there is a second tank that can still treat the water and allow time to replace the media in the first or lead tank. Periodic backwashing is also typically required to remove any trapped particles in the media bed. Typical design criteria are empty bed contact time (EBCT) and loading rate per volume of media. For the Purolite FerrIX media, the recommended EBCT is two to five minutes. The media bed is recommended to be a minimum of 30-inches deep and a loading rate of no more than six gallons per minute per cubic foot of media gpm/ft3). To know when one vessel’s media is spent and needs to be replaced, sample taps are typically installed in the side of the tank and at the outlet of each tank. Periodic monitoring and lab testing are required to determine when a media bed is spent and needs to be replaced. To replace the media there are a few methods for removing and replacing the media. Some vessels have specially designed floors that allow the media to be removed from a nozzle at the bottom of the vessel, while others are designed for a more manual approach by installing an access manway into the tank at the lower level and allowing media to be removed manually. Depending on the time between media replacements one or the other may be more appropriate. Some ion exchange media can be regenerated on-site. This process typically requires a high concentration of brine or other chemicals to be introduced into the tank with spent media. After a certain amount of time, the brine will preferentially pull the arsenic off of the media and attach it to the cleaning solution. This solution will then be wasted from the vessels and requires disposal and possibly additional treatment. Activated Alumina Using Activated Alumina (AA) in arsenic removal is very similar to the Ion Exchange methods. The Alumina is positively charged (chemically prepared) to bind the arsenic (AS-V) ions which have a negative charge to the media. The water leaves the arsenic behind as it passes relatively quickly through the media bed. AA has an extremely high surface area to volume ratio, so there are many locations for binding arsenic. Advanced AA methods have other additives such as iron, as well as various fabricated materials to aid in the binding of the arsenic. These advanced forms of AA can be more than five times as effective as the base AA media. A downside to all AA methods is the media are generally unable to be recycled, this means an agreement must be made with general landfills or sometimes hazardous waste landfills for disposal once the media is exhausted. Another challenge with activated alumina is pre-oxidation is required as As-III must be changed to As-V to readily bind with the media. The empty bed contact time for activated alumina is recommended to be 3 to 10 minutes and a bed depth of 3 to 6 feet is common. AA media beds require periodic backwashing like other treatment options. The backwash wastewater contains very little arsenic and can be sent to the sewer or treated on-site. AA media is a disposable media, meaning that once it is spent or exhausted, it is no longer usable and must be properly disposed of. Specific toxicity of the spent media varies from system to system and ---PAGE BREAK--- 21 testing can be completed to determine if the spent media would need to be sent to a hazardous waste landfill, or if it can be landfilled in a regular landfill. The media replacement is the same as described above for the ion exchange media. Depending on the time between media changes this can become a maintenance-intensive task. Other than media change- outs, the activated alumina process requires very little operator attention. Periodic water testing is required to determine when the media bed is spent as well. A typical AA setup is the same as the ion exchange (IX) system. A lead-lag setup is ideal where the water enters the top of the first vessel and flows downward then is directed to the top of the second vessel and again down through the media bed. This provides a level of redundancy and allows time for media replacement in the spent vessel while allowing the treatment process to continue. Iron-Based Sorbents There are several different types of iron-based sorbents. For this report, we will focus on Granular Ferric Hydroxide (GFH). The other products are very similar and most of the info contained herein will be the same for other iron-based sorbents. In general, iron-based sorbents are very similar to activated alumina (AA) in practice. The treatment setup and operating procedure are nearly identical. Granular Ferric Hydroxide Media (GFH) GFH’s chemical makeup is Fe2O3. GFH is an adsorbent specifically designed to remove both As-V and As- III forms of arsenic. This is a large advantage because it means there is no need for pre-oxidation to convert As-III to As-V. It is capable of removing other heavy metals and harmful compounds as well, including antimony, lead, copper, molybdenum, selenium (IV) and vanadium. GFH can last 4 or 5 times as long as carbon before it needs to be replaced. It works well with a pH of 5.5 to 9 and does not alter the pH of the water. The max operable temperature is 140° F and the volume of waste typically approaches 0.1%. The recommended contact time is a minimum of 3.5 minutes. Each system consists of two adsorbers, with all piping, valves, and gauges assembled. These systems are available in “Simplex, Duplex, or Triplex” configurations. Figure 7 below shows a typical GFH system setup from Evoqua Water Technologies. Additional drawings and technical data for the Evoqua system are included in Appendix 2. ---PAGE BREAK--- 22 Figure 7 - Evoqua GFH Typical Setup As far as maintenance goes, the replacement of the media is the main expense. Valves and instruments also need to be maintained to ensure that the system operates as it should. As in the case with AA, a downside is the need to dispose of the spent media in a general or hazardous waste landfill. High TOC values would necessitate the addition of carbon filtration as well. It is important to monitor the system to know when the lead vessel’s media has been exhausted so that media replacement can be done An iron-based sorbent system is similar in size and footprint as compared to ion exchange and activated alumina. All three of these treatment systems utilize a similar range of empty bed contact times and loading rates. The advantage of the GFH system is that it can remove AS-III as well as AS-V without the use of pre-oxidation. This would, therefore, limit the additional capital costs and ongoing chemical costs associated with other systems. Ultrafiltration (UF) Similar to RO, Ultrafiltration makes use of durable membranes to separate unwanted constituents from water. The filters have larger pore sizes than RO membranes with the smallest particles removed being from 0.005 to 0.1 microns (this includes viruses and all bacteria). All maintenance cleaning is done automatically with soaks, rinses, and backwashes performed as the system recognizes certain decreases in efficiency. So long as the water has a turbidity of less than 5 NTU, the total suspended solids are less than 5 mg/l, the total organic carbon is less than 3 mg/l, iron is less than 0.3 mg/l, manganese is less than 0.05 mg/l, minimal amounts of grease and oil are found in the water, and the use of charged polymeric flocculant aids are avoided, the process should work well for Minden’s wells. ---PAGE BREAK--- 23 WesTech has offered two separate designs for this specific project. The first consists of one membrane filtration unit sized to treat a gross influent flow of 1,200 gpm. The unit has capacity for up to 38 modules, with 32 installed, allowing for some future expansion. The second includes one membrane filtration unit sized to treat a gross influent flow of 2,000 gpm. It has capacity for up to 60 modules, with 54 installed. Ultrafiltration would require that the AS-III be oxidized and converted to AS-V before filtration. Ultrafiltration is an absolute barrier technology and therefore can achieve high removal efficiency. There are two types of ultrafilters available on the market. Outside/in filtration and inside/out filtration. The WesTech system is an outside/in. In addition to the filter elements, ultrafiltration systems require feed pumps, pre-strainer to remove any larger debris, valves, and instrumentation. Provisions also need to be made for a backwash supply. This can come directly from the system, or an onsite backwash storage tank. Filtered water is used for backwashing the filters periodically. Ultrafiltration backwash steps occur much more frequently than with other non-membrane technology, but they also are shorter and use less water each time. A typical backwash interval is between 20 and 60 minutes. Air scour is also typically used to improve backwash efficiency. Ultrafiltration systems have extensive control systems that automate the filtration, backwashing, maintenance cleans, and clean in place procedures. Additionally, WesTech’s system will perform a pressure decay test (PDT) once every 24 hours. This test can detect a single fiber break in the system and alert the operator of issues with the system. Chemical cleaning is similar to the RO system described above. The waste from the chemical cleaning process must be handled properly and accommodations made for proper disposal. Ultrafiltration is much more compact than IX, AA, and Iron-based Sorbent systems. For this reason, it is advantageous if small treatment sites are available. Figure 8 - WesTech's Ultrafiltration System ---PAGE BREAK--- 7/20/2020 24 Decision Matrix and Discussion To be able to rank the different treatment and mitigation solutions, a decision matrix was created to score each solution based on criteria judged to be pertinent to this study. The full decision matrix is included in Appendix 3. Below is a list of the treatment options as well as the definition used. · Long-Term Reliability: The potential for the mitigation strategy to remain effective with changing conditions into the future. Those options that are more resilient to changing water quality should be ranked higher. · Ease of Implementation: This is a measure of how much infrastructure would need to be installed for the mitigation to work. The more infrastructure that is required the lower the score. · Cost of Implementation: Scores were given based on the cost of implementation as shown in the next section as well as in the full cost estimates included in Appendix 3. · Effectiveness: The effectiveness score is based on how much of the arsenic the treatment option is able to remove. If the final expected effluent after treatment is less than 3 ppb Score = 10, 3 to less than 5 ppb Score = 8, 5 to less than 6 ppb Score = 6, 6 to less than 8 ppb Score = 4, 8 to less than 10 ppb Score = 2, greater than 10 ppb Score = 0 · Environmental Constraints: If any environmental constraints will limit the use of a treatment option, a lower score was given. If there are no environmental constraints, then a full score was given. · Footprint Required/Land Use: The smaller the footprint, the higher the score given to that option. · Scalability: The treatment’s ability to expand and scale up in the future was scored higher than those that were more difficult to expand and increase capacity. · Effectiveness with AS-III: If the treatment is able to treat AS-III without additional treatment steps such as oxidation, then a higher score was given. Three different scores were given. Those technologies that could radially treat for AS-III without additional treatment were given a full 10 points, those that could remove some AS-III were given a score of 5, and those that cannot treat for AS-III were given 0 points. · Fundability: If there are any issues with receiving state or federal funding for the treatment technology a lower score was applied. · Ease of Maintenance: The easier the treatment technology is to maintain, the higher the score. Maintenance also considers the number of parts and ancillary equipment that would be needed. · O&M Costs: If a treatment technology requires higher operations costs then it would receive a lower score. · Operator Skill Required: If the technology is very difficult to operate and requires a high level of operator attention and training, then it was scored lower. · Power Demand: The higher the power demand the lower the score. · Chemical Usage: The more chemical usage required, the lower the score · Waste Produced/Treatment Limitations: The more volume of waste produced and the higher toxicity of the waste received a lower score. · Social Limitations: If there are any negative social perceptions from customers or users that could negatively affect the project if the treatment was used then the given score would be lower. ---PAGE BREAK--- 25 Each of these categories was given a potential score with items deemed to be more influential given a higher possible score. The total possible score for all of the categories combined is 300. Capital Costs Cost estimates were created for each of the different treatment options. Land acquisition costs were assumed to be about $260,000/acre in the the cost estimate based on radially available property costs. General assumptions were made as to the total amount of piping and valves, plant layout, ancillary space requirements in the treatment building, and amenities required. These assumptions were kept uniform for each treatment option. The largest factor in the cost comparisons is the treatment equipment and the building size required. All other factors were similar between treatments. Two treatment plant locations were selected. One near Well 11 and referred to as the South-West Proposed Treatment Location and the other near Well 9 and referred to as the North-East Proposed Treatment Location. These locations were used to estimate pipe to get the water from the associated wells to the site. The maps are included in Appendix 4 for reference. The cost estimates are summarized in the table below with the lowest cost option listed first. Full cost estimates are included in Appendix 4 for reference. It is important to note that depending on when and if any well’s arsenic level exceeds the target limit it may necessitate blending with a different well than what was planned for in this study. Rank TREATMENT METHOD ESTIMATED COST 1 Blending – Pipe Well 2 to Blend with Well 11 $2,133,900 2 Blending – Pipe Well 2 to Blend with Well 3 $2,205,400 3 Blending – Pipe Well 7 to Blend with Well 8 $2,441,900 4 Blending – Pipe Well 5 to Blend with Well 11 $3,882,200 5 Blending – Pipe Well 7 to Blend with Well 9 $5,798,600 6 Blending – Pipe Well 7 & 8 to Blend with Well 9 $6,196,500 7 Ultrafiltration $10,251,800 8 Reverse Osmosis $10,298,400 9 Coagulation-Filtration (Pressure Filters) $10,937,800 10 Iron Based Sorbents (GFH) $10,947,300 11 Activated Alumina $10,989,600 12 Ion Exchange $11,049,300 As is shown in the table, the best options for mitigation are to blend the wells. This is also the lowest cost and maintenance option as well. Depending on how each well changes over time blending may or may not be a long-term solution but based on the trends we have seen blending is the first recommended solution once arsenic levels rise. The order of action is 1) No Action, 2) Blending, 3) Treatment. Ongoing operation and maintenance (O&M) costs are generically included in the decision matrix, but actual O&M costs have not been calculated and vetted as a part of this study. If the Town decides to move forward with any mitigation we suggest a preliminary engineering report (PER) be completed to fully assess the total lifetime costs and their impact on the Town’s ongoing operations and maintenance budget. ---PAGE BREAK--- 7/27/2020 26 Recommendations As was noted earlier, the arsenic concentrations in the Minden Town wells are trending lower. Assuming that this trend continues mitigation would not be needed. If, however, the arsenic concentrations start to increase, the mitigation measures described herein should be implemented. Based on the findings of this report and after ranking each of the different treatment options, we recommend blending be the first step in mitigation. Based on the arsenic concentrations in the wells, the first wells to need to be blended are 2, 5, and 11 in the southern portion of the Town and 7, 8, and 9 in the northern part of the Town. By doing this the overall concentration can be kept close to or below the target of 7 ppb. The challenge with blending is piping the wells together and creating a higher point flow into the system at the blending locations. Preliminary model projections show that doing so will not adversely impact the system’s pressures or flows. A control strategy will need to be developed to properly blend water from each well to ensure that proper ratios of each well are maintained. As discussed above, there will need to be flow meters and modulating control valves installed that can control and maintain the flow from each well to properly proportion the water. The costs are estimated to be; · Pipe Well 2 to Well 11 $2,133,900 · Pipe Well 2 to Well 3 $2,205,400 · Pipe Well 7 to Well 8 $2,441,900 · Pipe Well 5 to Well 11 $3,882,200 · Pipe Well 7 to Well 9 $5,798,600 · Pipe Wells 7 & 8 to Well 9 $6,196,500 Depending on which well develops an arsenic concentration high enough will dictate which wells should be blended. If the Town determines that they need additional capacity, Well 7 could be blended with either Well 8 or Well 9 to provide additional source capacity to the system. A secondary mitigation option could be to locate a new source that has lower arsenic levels. Based on the map included in Appendix 1 it appears that there is water with lower arsenic south of Minden and Gardnerville. Doing this has the potential for higher costs due to the potential distance away from the rest of the system, but could be a possibility. If the levels of arsenic generally increase throughout all wells this would necessitate treatment beyond blending. For this situation we recommend Ultrafiltration be used. This treatment has the lowest cost of all of the treatment options. Ultrafiltration also is very compact and provides a positive barrier that can give a level of assurance in the treatment process. Depending on the speciation of the arsenic in the water to be treated, oxidation may (and likely will) be required. This can be accomplished in the pipe before treatment by adding chlorine or another oxidizing agent upstream of the treatment plant. We recommend a more detailed preliminary engineering report (PER) be completed along with piloting to determine the final design parameters for an Ultrafiltration system. Depending on the timing of the need for treatment other new technologies could become available and may prove to be better options for Minden. ---PAGE BREAK--- 27 Implementation Strategy To be ready to implement any mitigation strategy, the Town needs to have the financial resources in place to be able to complete any of the recommended projects. Funding options may be available and should be explored to help the Town with the costs to implement an arsenic mitigation strategy. It is recommended that the Town continue to monitor and record the arsenic concentrations at each well at least semi-annually. The testing results should be plotted to monitor arsenic concentration trends. Doing this should make it clear if there are changes in arsenic concentrations that will necessitate further mitigation. This monitoring will help the Town prepare as the arsenic levels won’t likely spike all at once but will likely slowly trend upwards (or downwards) over time. Since the target for the system is 7 ppb, careful attention should be paid to any well producing water with arsenic above 6 ppb. These wells will need to be treated first. Once a well is identified as needing or likely needing treatment, plans should be started to implement the recommended strategies described above. First plan on blending if the well to blend with has a sufficiently low arsenic level. If treatment is required land should be acquired and plans should be started for pilot testing the water to determine final design criteria for the treatment plant. Action Items · Monitor each well at least semi-annually · Plot arsenic levels and identify trends (higher or lower arsenic concentrations) · Identify potential new water sources/well locations · If a well starts trending to higher arsenic concentrations begin to design for blending with a lower concentration well · If blending is not sufficient, initiate a PER and pilot study to identify design parameters for the treatment plant · Acquire land for a treatment plant · Design and construct a treatment plant ---PAGE BREAK--- 7/20/2020 28 Conclusions Minden Town’s water system draws water from several wells throughout the Town. The arsenic concentration in some of the wells is somewhat high yet still below the EPA mandated MCL of 10 ppb except for Well 7. The arsenic concentrations in Minden’s wells have changed over time and will likely continue to do so; however, in the last few years, the overall trend has been diminishing concentrations. Since Minden wholesales water and operates wells that have associated water rights from other water systems that have higher arsenic concentrations in their water, a target concentration of 7 ppb for the maximum arsenic concentration in the Minden system was suggested by the participating agencies. If the overall arsenic concentration in Minden’s system is below 7 ppb, the other systems that blend their water with Minden’s water will be able to stay below the EPA MCL of 10 ppb. To understand when mitigation is required to maintain water in the system at or below 7 ppb, the first step should be to monitor each well and identify which well’s concentration is increasing, then blend water from wells whose water has less arsenic with wells that have higher arsenic concentrations. We recommend blending Wells 2 and 3, Wells 5 and 11 first. Second, investigations could be made to try to relocate a well to a location where there is lower arsenic in the water. Third, based on the evaluation performed for this study, Ultrafiltration would be the preferred treatment option for mitigating arsenic in the water. We recommend blending the flows from Wells 7, 8, and 9 into a common location near well 9 and treat a portion of the flow to produce a final effluent concentration at or below 7 ppb. A preliminary engineering report and pilot testing should be completed to determine the final design criteria for treatment. ---PAGE BREAK--- 2/20/2020 29 Appendix 1 – Arsenic Maps ---PAGE BREAK--- www.sunrise-eng.com WASHINGTON, UT 84780 11 NORTH 300 WEST TEL [PHONE REDACTED] Z FAX [PHONE REDACTED] ENGINEERING ARSENIC CONCENTRATIONS IN CARSON VALLEY ---PAGE BREAK--- www.sunrise-eng.com WASHINGTON, UT 84780 11 NORTH 300 WEST TEL [PHONE REDACTED] Z FAX [PHONE REDACTED] ENGINEERING AVERAGE AS CONCENTRATIONS IN MINDEN'S WE ---PAGE BREAK--- 2/20/2020 32 Appendix 2 – Treatment Equipment Information ---PAGE BREAK--- B U C K E Y E R D . S. B E N T L E Y P A R K W A Y V E C T O R D R. W N C M I D V A L L E Y N. B E N T L Y P A R K W A Y O R B I T W A Y B U C K E Y E R D . V E C T O R D R. D R D. SS #11 132028000015 132027001021 132028000017 132027001006 132027002008 132027001010 132028000007 132027002033 132027002026 132027002034 132027002029 132027001004 132027001007 132028000014 132027001009 132027001023 132027002027 132027001022 132027001008 132028000011 132027001020 132027001020 WELL #9 WELL #7 WELL #8 B E N T L Y S C I E N C E P A R K www.sunrise-eng.com WASHINGTON, UT 84780 11 NORTH 300 WEST TEL [PHONE REDACTED] Z FAX [PHONE REDACTED] ENGINEERING NORTH-EAST PROPOSED TREATMENT LOCATIO ---PAGE BREAK--- N O T A P A R T T A P A R T N O T A P A R T TOWN OF MINDEN BOUNDARY http://www.myspace.com/turdcutter942 N O T A P A R T N O T A P A R T ROSSO CT. U G L A S U N T Y R A R Y C O U N T Y C O U R T H O U S E D O U G L A S D O U G L A S S C H O O L C O U N T Y D I S T R I C T M I N D E N P A R K C I V I C H A L L S E E M A N M U L R E A N Y M A R T I N S L O U G H S E E M A N H E A R T H S T O N E S U B D I V I S I O N B E N T L Y V E R I Z O N M A C K R A N C H C O T T O N W O O D S L O U G H A T G A R D N E R V I L L E L L C T H E R A N C H E P I S C O P A L C H U R C H SANFORD WY. T O W N O F M I N D E N B O U N D A R Y U . S . H I G H W A Y 3 9 5 BROOK MINDEN VILLAGE LOOP B U C K B U C K E Y E R O A D MONTICELLO CT. M A R T I N S L O U G H SS #1 N O T A P A R T TOWN OF MINDEN BOUNDARY GARDNERVILLE RANCH D SIXTH ST TENTH ST NINTH ST EIGHTH ST SEVENTH ST FIFTH ST MONO AV EIGHTH ST (aka Water St) FOURTH ST THIRD ST SECOND ST FIRST ST TENTH ST LUCERNE ST ESMERALDA AV WILDROSE DR WILDROSE DR MONO AV COUNTY RD BUCKEYE RD BELARRA DR ZALDIA DR MACKLAND AV OLUA ST IRONWOOD DR LUCERNE ST HIA CR ZEROLENE RD U.S. HIGHWAY 395 NORTH COUNTY RD ESMERALDA AV U.S. HIGHWAY 395 NORTH CARVAL CT OLUA ST LUCERNE ST ALLEY ZEROLENE PL FREIDA LN FREIDA LN BUCKEYE RD VILLAGE SQUARE DOUGLAS COUNTY JUDICIAL COMPLEX CARSON VALLEY INN BENTLY NEVADA COD GARAGE MINDEN INN MINDEN PLAZA MINDEN TOWNHOUSES GALANTE RD. BALER ST. MONTE VISTA AVE. 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132032111017 132032111021 132030810007 132030810010 132030810008 132030802012 132030814007 132030814006 132030814004 132030814002 132030814001 132030814008 132030814003 132030814009 132030814005 132030810002 132030810003 132030810006 132030810004 132030810005 132030710011 132030710024 132030710028 132030710020 132030710016 132030710015 132030710012 132030710003 132030710007 132030710019 132030710027 132030710023 132030710031 132030810011 132030710010 132030710017 132030710021 132030710032 132030710009 132030710026 132030710022 132030710018 132030710013 132030710014 132030710005 132030710029 132030710025 132032102001 132030810009 30820012 [PHONE REDACTED] 132030810012 NDARY WELL #3 WELL #2 P O S T O F F I C E WELL #1 TOWN OF MINDEN BOUNDARY TOWN OF MINDEN BOUNDARY T O W N O F M I N D E N B O U N D A R Y TOWN OF MINDEN BOUNDARY TOWN OF MINDEN BOUNDARY TOWN OF MINDEN BOUNDA www.sunrise-eng.com WASHINGTON, UT 84780 11 NORTH 300 WEST TEL [PHONE REDACTED] Z FAX [PHONE REDACTED] ENGINEERING SOUTH-WEST PROPOSED TREATMENT LOCATIO ---PAGE BREAK--- QR-00-085B Engineer Sunrise Engineering Represented by Mike Charnholm Goble Sampson Associates Salt Lake City, Utah (801) 268-8790 [EMAIL REDACTED] Furnished by Adrian Williams [EMAIL REDACTED] Minden Nevada WesTech Opportunity Number: 2030102 Wednesday, March 18, 2020 ---PAGE BREAK--- Proposal No. 2030102 Item A – Ultrafiltration Systems Design Overview Description Unit 1,200 gpm System 2,000 gpm System Application - Targeted Contaminant Removal WesTech System Model - UF81A, Ultrafiltration System Membrane Module - Toray HFUG-2020AN Gross Influent Flow Rate gpm 1,200 2,000 Net Product Flow Rate gpm 1,159 1,932 Redundancy and Unit Quantity - 1 x 100%, 1 total unit 1 x 100%, 1 total unit Approximate Dimensions Per Unit 18’-7” x 5’-4” W x 11’-5” H 27’-1” L x 5’-6” W x 12’-0” H Number of Modules Per Unit 32 installed, 38 capacity 54 installed, 60 capacity WesTech is a leader in innovative membrane filtration system technology, including VersaFilter™ open- platform systems, AltaPac™ packaged systems, retrofit engineering solutions, intelligent controls and performance analysis technology. Systems are skid-mounted and factory-tested for ease of installation, straightforward operation, and long-term reliability. Major equipment and valves are pre-configured for efficient and error-free commissioning. Controls are fully automated and completed by in-house electrical engineers and process automation experts. In addition to UF/MF equipment, WesTech is one of the only membrane system suppliers that offers pre- and post-treatment equipment for an integrated, complete process with consolidated equipment support. Notably, WesTech has more pretreatment equipment to UF/MF systems than any supplier. Our membrane filtration team has provided more than 100 membrane systems throughout North America with UF/MF installations in excess of 6,945 gpm. As a company, WesTech has 530 employees, 190 degreed engineers, and more than 15,000 process equipment installations throughout the world. This significant experience translates into reliable, time-tested equipment. A WesTech Ultrafiltration System rated for 3 MGD capacity. ---PAGE BREAK--- Proposal No. 2030102 Design Information Water Quality WesTech UF/MF systems will consistently produce high purity treated water even with variation in the feed source due to a small nominal pore size in an absolute barrier configuration. Feed Water Quality* Description Unit Concentration Source - Well Water pH - 6.5 – 8.5 Temperature °C 10 Turbidity NTU < 5 Total Suspended Solids mg/L < 5 Total Organic Carbon mg/L < 3 Iron mg/L < 0.3 Manganese mg/L < 0.05 *Values are assumed and should be verified. It is noted that the use of charged polymeric flocculant aids increases risk of irreversible membrane fouling and should be discussed with WesTech, and this risk is applicable to all polymeric MF/UF membrane manufacturers. The presence of oil and grease in the source water should also be minimized. Treated Water Quality Description Unit Concentration Turbidity NTU ч 0.10 NTU 95% of the time with a maximum turbidity of 0.3 NTU Total Suspended Solids mg/L < 1 Silt Density Index - ч 3 Giardia Removal* - ш 4 log (99.99%) Removal* - ш 4 log (99.99%) Virus Removal* - ш 1.0 log removal (90.00%) Certification Standards NSF 61, NSF 419, UL 508A Listed *Challenge-testing certification is provided by independent evaluation through NSF/ANSI 419. Typical removal levels exceed the certification level and are often on the order of 6-log. Additionally, the UF membranes achieve 1.5 log removals of viruses, though virus removal certification is only recognized up to 1.0 log by CDDW for any membrane filter. Ultrafiltration is an excellent choice for arsenic removal due to ultrafiltration being an absolute barrier technology. Oxidation and precipitation of the arsenic would be required upstream of the ultrafiltration system in order to properly filter the arsenic, as ultrafiltration only removes suspended solids and not dissolved solids. High removal efficiency can be achieved with appropriate pretreatment chemistry and coprecipitation to produce a filterable particulate that can be removed by size-exclusion. ---PAGE BREAK--- Proposal No. 2030102 Process Description Described in this proposal is the preliminary process and design of the WesTech membrane filtration system for the Minden, Nevada project. The first system design consists of one membrane filtration unit sized to treat a gross influent flow of 1,200 gpm. The unit has capacity for up to 38 modules, with 32 installed. The second system design consists of one membrane filtration unit sized to treat a gross influent flow of 2,000 gpm. The unit has capacity for up to 60 modules, with 54 installed. The filtration process is an outside/in, pressure-driven process to remove suspended solids and turbidity, and to achieve 4-log reduction of pathogens like Giardia and Raw water from the water source is subject to pretreatment by chemical addition for oxidation of metals. VFD-controlled feed pumps (by others) direct the source water to a 200 µm pre-strainer for removal of larger debris. Filtrate is sent to the backwash supply tank (by others). Backwashing is used to remove accumulated foulants by reversed inside/out flow at an interval of 20 - 60 minutes with air scour for increased agitation. A drain or filter-to-waste step is used to remove any additional accumulated material. Membrane integrity testing is conducted automatically once every 24 hours. The pressure decay test (PDT) is capable of detecting a single fiber break. Maintenance cleans (MCs)/chemically-enhanced backwashes (CEBs) and clean-in-place (CIP) procedures are automated chemical cleaning processes used to recover membrane permeability. MCs/CEBs are typically performed with NaOCl once per day to once per week. The automated clean-in-place procedure is designed to occur no more frequently than once per month, is conducted with either NaOCl or acid, and is initiated when membrane permeability decreases to a specified value. Following chemical cleaning procedures, the membrane units are drained by gravity or a pressurized drain-to-waste, and waste is subsequently sent to the discharge location. A rinse step and backwashing are used to remove residual chemical prior to resuming production. If desired, chemical cleaning waste can be captured and neutralized prior to discharge. ---PAGE BREAK--- Proposal No. 2030102 Process Design Summary Detailed Design Summary Parameter 1,200 gpm System 2,000 gpm System Number of Units in System 1 1 Number of Units in Operation 1 1 WesTech System Model UFT81A UFT81A Installed Modules per Unit 32 54 Total Module Capacity per Unit 38 60 Module Model Toray HFUG-2020AN Toray HFUG-2020AN Membrane Area per Module 969 ft² 969 ft² Membrane Area in Operation 31,008 ft² 52,326 ft² Design Temperature 50.0 °F 50.0 °F Production Cycle Time 30 min 30 min Flux Rates Instantaneous Flux at Design Temp. 61.4 gfd 60.7 gfd Normalized Flux (20°C) at Design Temp. 80.4 gfd 79.4 gfd Flow Rates Instantaneous Flow Rate 1,323 gpm 2,204 gpm Average Gross Flow Rate 1,200 gpm 2,000 gpm Average Net Filtrate 1,159 gpm 1,932 gpm Backwash Flow Rate 1,455 gpm 2,425 gpm Approx. Net Filtrate Production per Day 1,669,380 gpd 2,781,930 gpd Backwash Waste Volume per Day 31,441 gpd 52,401 gpd Influent Used for Rinsing/Draining per Day 27,182 gpd 45,661 gpd Water Recovery > 95 % > 95% Estimated Maintenance Clean Frequency Daily to Weekly Daily to Weekly Estimated Clean-In-Place Frequency 30 days 30 days ---PAGE BREAK--- Proposal No. 2030102 Scope of Supply Scope of Supply – Ultrafiltration System Item Quantity Description Brand (or Equal) Membrane Modules 1,200 gpm system 2,000 gpm system 32/unit 54/unit Hollow-fiber, outside-in UF, PVDF/TIPS, 0.01 µm Toray Skid Frames 1 x 100% Welded carbon steel, baked powder-coat - Manifold and Supply Piping - Schedule 80 PVC/HDPE feed/filtrate connections - Feed Pump By Others - By Others Backwash Pump By Others - By Others Pre-strainer 1 x 100% 200-micron, automatic backwashing Forsta Compressed Air System By Others Plant air assumed available By Others Turbidimeter 1/unit feed 1/unit filtrate 2 total/unit TU5300 sc TU5300 sc Hach Hach Flow Meters 1/unit Bi-directional magnetic flow meter with transmitter Siemens Pressure Instrumentation - Transmitters, switches, gauges Wika, Ashcroft Valves / Actuators - Manual and actuated valves Bray Electrical Control Panels 1 Master/system 1 Local/unit NEMA 4, 480 V, 3 ph, PLC, HMI Remote I/O - Tanks By Others Feed, backwash HDPE with level measurement By Others Feed Chemical Addition Chemical Dosing Pump(s) Static Mixer/Tank By Others By Others Metals Oxidation/Coagulation Metals Oxidation/Coagulation By Others By Others ---PAGE BREAK--- Proposal No. 2030102 Scope of Supply – Clean-in-Place System* Item Quantity Description Brand (or Equal) Skid Frames 1 x 100% Welded carbon steel, baked powder-coat - Manifold and Supply Piping - Schedule 80 PVC 6” supply/return connections - Recirculation Pump 1 x 100% End-suction centrifugal Close-coupled Goulds Heater 2 24 kW Chromalox Pre-Strainer 1 x 100% Superleader Arkal Chemical Metering Pumps Sodium Hypochlorite Citric Acid 1 x 100% 1 x 100% CIP/MC process CIP/MC process ProMinent ProMinent Instrumentation pH Sensor/Transmitter Temperature Transmitter Flow Switch 1 1 1 - - - GF Signet Dwyer IFM Efector Pressure Instrumentation - Transmitters, switches, gauges Wika, Ashcroft Valves / Actuators - Manual and actuated valves Bray Electrical Controls 1 CIP Panel NEMA 4, 480 V, 3 ph - Tank By WesTech Off-skid HDPE with level measurement Norwesco *The CIP System has capacity to be used for either the 1,200 gpm or 2,000 gpm design. Additional Services On-Site Technical Assistance and Training WesTech has included on-site technical assistance during construction, pre-commissioning and start-up to ensure the equipment is installed and commissioned per WesTech’s and sub-suppliers’ requirements. All service visits will be completed by certified field technicians that are qualified and have experience working with WesTech equipment. Any additional trips that the customer may request can be purchased at the standard WesTech daily rates plus travel and living expenses. On-Site Technical Service Service Number of Trips Number of Days Installation and Start-Up Commissioning Assistance, Operator Training 2 10 Total Included Service 2 10 ---PAGE BREAK--- Proposal No. 2030102 To supplement the above noted technical assistance, WesTech will provide the additional services. x Technical support during WesTech office hours with a direct phone number to reach a qualified and involved project representative during the equipment warranty period. x Access to a 24-hour on-call emergency support line. This proposal has been reviewed and is approved for issue by Chelsea Stewardson on March 18, 2020 ---PAGE BREAK--- Proposal No. 2030102 Item B – Reverse Osmosis System Design Overview Description Unit 1,200 gpm System 2,00 gpm System Application - Targeted Contaminant Removal WesTech System Model - ROT81B, Reverse Osmosis System ROT82B, Reverse Osmosis System Membrane Element - Toray Gross Influent Flow Rate gpm 1,200 2,000 Net Product Flow Rate gpm 900 1,500 Anticipated Recovery % 75 75 Redundancy and Unit Quantity - 1 x 100%, 1 total unit 2 x 50%, 2 total units Approximate Dimensions Per Unit 26’-7” L x 6’-0” W x 12’-3” H 26’-7” L x 6’-0” W x 12’-3” H Array - 17:8 7M 14:7 7M WesTech is an experienced and reliable provider of nanofiltration/reverse osmosis (NF/RO) systems including new installations, retrofit and support of existing systems, and packaged systems. Systems are designed for ease of installation, straightforward operation, and long-term reliability. WesTech systems are provided as skid-mounted, factory-tested units to minimize field assembly. Major equipment and valving are pre-configured on the skids for efficient and error-free commissioning. Controls are fully- automated and completed by in-house electrical engineers and process automation experts. Our membrane filtration team has provided more than 100 membrane systems throughout North America with NF/RO installations in excess of 4,800 gpm As a company, WesTech has 530 employees, 190 degreed engineers, and more than 15,000 process equipment installations throughout the world. This significant experience translates into reliable, time-tested equipment. A WesTech Reverse Osmosis System rated for 2,000 gpm capacity. ---PAGE BREAK--- Proposal No. 2030102 Design Information Water Quality The proposed systems have been designed based on a feed TDS value of 240 mg/L. A complete water quality analysis will be required to verify the proposed design. The water quality analysis should include as many of the following constituents as possible: x Calcium (Ca) x Magnesium (Mg) x Sodium (Na) x Potassium x Barium (Ba) x Strontium (Sr) x Ammonia (NH4) x Iron (Fe) x Bicarbonate (HCO3) x Chloride (Cl) x Sulfate (SO4) x Nitrate (NO3) x Fluoride x Bromide (Br) x Boron x Silica (SiO2) x Phosphate (PO4) x TDS (mg/L) x TSS (mg/L) x Turbidity (NTU) x pH x Temperature The single pass RO system is designed to remove dissolved contaminants from the inlet water source with a silt density index (SDI) consistently of 5 or lower, such as ultrafiltration. The recovery of the system is preliminarily designed as 75% but may be improved or hampered by changes in the water quality and fluctuations in dissolved constituent concentrations, like TDS. The RO system has a nominal rejection rate of 95 – 99% of dissolved materials including hardness and TDS. Reverse osmosis is an excellent choice for arsenic removal. Rejection of dissolved arsenic is dependent on the species present in the feed water. The arsenite, or As (III), species is uncharged and undissociated, meaning that rejection is more difficult. Typical rejections for As (III) is estimated to be ч 70%. Arsenate, or As is charged and dissociated, therefore rejection is much higher (ш 90%). ---PAGE BREAK--- Proposal No. 2030102 Process Description Described in this proposal is the preliminary process and equipment design of a WesTech reverse osmosis membrane filtration system for the Minden, Nevada project. The first system design consists of one membrane filtration unit sized to treat a gross influent flow of 1,200 gpm. The unit is designed as a single-pass, two-stage system in a 17:8 7M configuration with 175 elements installed. The overall system recovery is targeted as 75%. The second system design consists of two membrane filtration units each sized to treat a gross influent flow of 1,000 gpm for an overall treatment capacity of 2,000 gpm. The units are designed as a single-pass, two-stage system in a 14:7 7M configuration with a total of 294 elements installed. The overall system recovery is targeted as 75%. Reverse osmosis technology uses semi-permeable membranes for removal of dissolved contaminants, such as TDS, chlorides, and hardness from water. The basic principle of RO involves application of high pressure to counteract natural osmotic pressure to drive water from a more concentrated, feed solution to a pure water permeate. Dissolved impurities are removed during this process. The process utilizes cross-flow filtration to remove dissolved contaminants from the feed stream, producing a purified water stream (permeate) and a high-solute waste stream (concentrate). Feed water quality will determine the amount of permeate capable of being recovered from feed water. Raw water from the well water source is directly fed to the membrane system. VFD-controlled feed pumps (by others) directs the source water to a 5-µm cartridge filter for removal of larger debris. VFD-controlled high-pressure pumps boost the feed pressure provided by the feed pumps and drive water through the membranes. Clean-in-place (CIP) procedures are automated chemical cleaning processes used to recover membrane permeability. The automated clean-in-place procedure is conducted with either sodium hydroxide or hydrochloric acid. A CIP is initiated when normalized permeate flow decreases by ш10%, normalized salt passage increases by ш10%, or normalized differential pressure increases by ш15%. Following chemical cleaning procedures, the membrane units are flushed to remove residual chemical prior to resuming production. If desired, chemical cleaning waste can be captured and neutralized prior to discharge. ---PAGE BREAK--- Proposal No. 2030102 Process Design Summary Detailed Design Summary Parameter 1,200 gpm System 2,000 gpm System Number of Units and Redundancy 1 x 100% 2 x 50% Array Configuration 17:8 7M Single Pass / Two-Stage 14:7 7M Single Pass / Two-Stage Membrane Element Toray TMG20D-400 Toray TMG20D-400 Elements per Skid 175 147 Membrane Area per Element / Diameter 400 ft2 / 8 in 400 ft2 / 8 in Total Membrane Area Installed 70,000 ft2 117,600 ft2 Design Temperature 50 °F 50 °F Average Flux Rate 18.5 gfd 18.4 gfd Operating Flow Rates Feed Flow Rate Permeate Flow Rate Concentrate Flow Rate 1,200 gpm 900 gpm 300 gpm 2,000 gpm 1,500 gpm 500 gpm Approx. Total Net Permeate Production per Day 1,296,000 gpd 2,160,000 gpd Approx. Total Concentrate Volume per Day 432,000 gpd 720,000 gpd Overall System Recovery 75 % 75 % Projected Feed Pressure 170 psig 170 psig ---PAGE BREAK--- Proposal No. 2030102 Scope of Supply Scope of Supply – Reverse Osmosis System Item Quantity Description Brand (or Equal) Membrane Elements 1,200 gpm system 2,000 gpm system 175/unit 147/unit Spiral wound, thin-film composite, polyamide Toray Skid Frames 1,200 gpm system 2,000 gpm system 1 x 100% 2 x 50% Welded carbon steel, baked powder-coat - Manifold and Supply Piping - Low Pressure: Sch 80 PVC High Pressure: 316 SS - Element Housings 1,200 gpm system 2,000 gpm system 25/unit 21/unit FRP Codeline Feed / Transfer Pump By Others End-suction centrifugal By Others High Pressure Pump 1/unit Multi-stage; note that pressure to the high pressure pump must be 30 psi or greater Goulds Cartridge Filters and Vessels 1/unit Stainless steel Fil-Trek Compressed Air System By Others Plant air is available for valve actuation By Others Instrumentation Conductivity Sensor ORP Sensor/Trans. pH Sensor/Trans. Temperature Trans. 2/unit 1/system 1/system 1/system Feed/permeate Combined feed Combined feed Combined feed GF Signet GF Signet GF Signet Dwyer Flow Meters 2/unit Magnetic flow meter Feed / concentrate Siemens Pressure Instrumentation - Transmitters, switches, gauges Wika Valves / Actuators - Manual and actuated valves Bray Electrical Control Panels 1 Master/system 1 Local/unit NEMA 4, Allen-Bradley PLC - Tanks By Others Feed, Permeate HDPE with level measurement By Others Feed Chemical Addition Antiscalant Pump 1 x 100% - Watson Marlow ---PAGE BREAK--- Proposal No. 2030102 Scope of Supply – Clean-in-Place System Item Quantity Description Brand (or Equal) Skid Frames 1 Welded carbon steel, baked powder-coat - Manifold and Supply Piping - Schedule 80 PVC - Recirculation Pump 1 x 100% End-suction centrifugal Goulds Cartridge Filters 1 x 100% 5-micron pore size Fil-Trek Heater 2 24 kW Chromalox Chemical Metering Pumps Acid Alkaline 1 x 100% 1 x 100% CIP process CIP process ProMinent ProMinent Instrumentation pH Sensor/Transmitter Temperature Transmitter Flow Switch 1 1 1 - - - GF Signet Dwyer IFM Efector Pressure Instrumentation - Transmitters, switches, gauges Wika, Ashcroft Valves / Actuators - Manual and actuated valves Bray Electrical Controls 1 CIP Panel NEMA 4, 480 V 3 ph - Tank By WesTech Off-skid; HDPE with level meas. Norwesco *The CIP System has capacity to be used for either the 1,200 gpm or 2,000 gpm design. Additional Services On-Site Technical Assistance and Training WesTech has included on-site technical assistance during construction, pre-commissioning and start-up to ensure the equipment is installed and commissioned per WesTech’s and sub-suppliers’ requirements. All service visits will be completed by certified field technicians that are qualified and have experience working with WesTech equipment. Any additional trips that the customer may request can be purchased at the standard WesTech daily rates plus travel and living expenses. On-Site Technical Service Service Number of Trips Number of Days Installation and Start-Up Commissioning Assistance, Operator Training 2 10 Total Included Service 2 10 ---PAGE BREAK--- Proposal No. 2030102 To supplement the above noted technical assistance, WesTech will provide the additional services. x Technical support during WesTech office hours with a direct phone number to reach a qualified and involved project representative during the equipment warranty period. x Access to a 24-hour on-call emergency support line. This proposal has been reviewed and is approved for issue by Chelsea Stewardson on March 18, 2020 ---PAGE BREAK--- Proposal No. 2030102 Budget Pricing Proposal Name: Minden, Nevada Proposal Number: 2030102 Wednesday, March 18, 2020 1. Bidder's Contact Information Company Name WesTech Engineering, Inc. Contact Name Adrian Williams Phone [PHONE REDACTED] Email [EMAIL REDACTED] Address: Number/Street 3665 S West Temple Address: City, State, Zip Salt Lake City, UT 84115 2. Pricing Currency US Dollars Scope of Supply A-1 Ultrafiltration System – 1,200 gpm $500,000 A-2 Ultrafiltration System – 2,000 gpm $630,000 B-1 Reverse Osmosis System – 1,200 gpm $610,000 B-2 Reverse Osmosis System – 2,000 gpm $940,000 Taxes (sales, use, VAT, IVA, IGV, duties, import fees, etc.) Not Included Prices are for a period not to exceed 30 days from date of proposal. Field Service Daily Rate $1,200 Prices do not include field service unless noted, but it is available at the daily rate plus expenses. The customer will be charged for a minimum of three days for time at the jobsite. Travel will be billed at the daily rate. Any canceled charges due to the customer's request will be added to the invoice. The greater of visa procurement time or a two week notice is required prior to trip departure date. 3. Payment Terms Submittals Approved 15% Release for Fabrication 35% Net 30 days from Shipment 50% All payments are net 30 days. Partial shipments are allowed. Other terms per WesTech proforma invoice. 4. Schedule Submittals, after PO receipt 6 to 8 Weeks Customer Review Period 2 weeks Ready to Ship, after Submittal Approval 18 to 20 weeks Total Weeks from PO to Shipment 26 to 30 weeks ---PAGE BREAK--- Proposal No. 2030102 Terms & Conditions: This proposal, including all terms and conditions contained herein, shall become part of any resulting contract or purchase order. Changes to any terms and conditions, including but not limited to submittal and shipment days, payment terms, and escalation clause shall be negotiated at order placement, otherwise the proposal terms and conditions contained herein shall apply. Freight: Prices quoted are F.O.B. shipping point with freight allowed to a readily accessible location nearest to jobsite. All claims for damage or loss in shipment shall be initiated by purchaser. Paint: If your equipment has paint included in the price, please take note to the following. Primer paints are designed to provide only a minimal protection from the time of application (usually for a period not to exceed 30 days). Therefore, it is imperative that the finish coat be applied within 30 days of shipment on all shop primed surfaces. Without the protection of the final coatings, primer degradation may occur after this period, which in turn may require renewed surface preparation and coating. If it is impractical or impossible to coat primed surfaces within the suggested time frame, WesTech strongly recommends the supply of bare metal, with surface preparation and coating performed in the field. All field surface preparation, field paint, touch-up, and repair to shop painted surfaces are not by WesTech. ---PAGE BREAK--- ISOMETRIC REV - SHEET DOCUMENT NUMBER 2001 1 OF 3 TITLE GENERAL ARRANGEMENT, RO SKID RO SYSTEM 24 VESSELS VO00 DESIGNER CHECKER APPROVER THIS DRAWING IS PROPERTY OF WESTECH ENGINEERING, INC. AND IS TRANSMITTED IN CONFIDENCE. NEITHER RECEIPT NOR POSSESSION CONFERS OR TRANSFERS ANY RIGHTS TO REPRODUCE, USE, OR DISCLOSE, IN WHOLE OR IN PART, DATA CONTAINED HEREIN FOR ANY PURPOSE, WITHOUT THE WRITTEN PERMISSION OF WESTECH ENGINEERING, INC. DATE C:\Vault\Design\Jobs\22800\22838B Smoky Canyon\2001-GENERAL ARRANGEMENT, RO SYSTEM.idw ITEM EQUIPMENT DESCRIPTION MAT'L 1 (24) PRESSURE VESSELS, 16:8 6M FRP 2 PRESSURE VESSEL SKID STL 3 CONTROL PANEL STL 4 FLOW METERS - CONNECTION SUMMARY NOZZLE SIZE TYPE MAT'L DESCRIPTION A 6" FLG CI RO FEED B 6" FLG CI OFF-SPEC RO PERMEATE TO UF FILTRATE BREAK TANK C 6" FLG CI RO PERMEATE TO RO PERMEATE TANK D 6" FLG CI RO FEED FLUSH / CIP SUPPLY STAGE 1 E 3" FLG SS CIP RETURN STAGE 1 / SUPPLY STAGE 2 F 3" FLG CI CIP RETURN STAGE 2 G 3" FLG SS RO CONCENTRATE H 6" FLG CI CIP RETURN (RO PERMEATE) J 1/2" NPT SS AIR SUPPLY H C F 1 PROCESS DESIGN INFORMATION GPM PERMEATE FLOW (PER SKID): FEED PRESSURE: AVERAGE FLUX: PSI GFD DESIGN MINIMUM TEMPERATURE: REQUIRED FEED: RECOVERY: NTU % 500 14.28 172 75 <0.1 5 °C DESIGN FLUSH RATE: 420 GPM J A E 3 NOTES: 1. FOLLOW THE LISTED WESTECH REFERENCE DOCUMENTS EXCEPT AS NOTED ON THIS DRAWING. 2. ALL FLANGED CONNECTIONS TO BE 150# RAISED FACE. 3. SKID CONNECTIONS NOT DESIGNED TO BEAR PLANT PIPING LOADS. PLANT PIPING MUST BE PROPERLY SUPPORTED. 4. EQUIPMENT MUST BE LEVEL AFTER INSTALLATION. 5. AIR PIPING TO BE 304 SS, ALL OTHER SKID PIPING TO BE SCH 80 PVC/304 SS. 6. ALL VALVE ACTUATOR AIR SUPPLY TUBING TO BE POLYURETHANE. REFERENCE DOCUMENTS REV REVISION DESCRIPTION ECN DESIGNER APPROVER DATE PREPARED FOR ENGINEER CONTRACTOR PO/CONTRACT NUMBER CUSTOMER G PRELIMINARY NOT FOR CONSTRUCTION ---PAGE BREAK--- FRONT PLAN A SEE SHEET 3 A REV - SHEET DOCUMENT NUMBER 2001 2 OF 3 TITLE GENERAL ARRANGEMENT, RO SKID RO SYSTEM 24 VESSELS VO00 DESIGNER CHECKER APPROVER THIS DRAWING IS PROPERTY OF WESTECH ENGINEERING, INC. AND IS TRANSMITTED IN CONFIDENCE. NEITHER RECEIPT NOR POSSESSION CONFERS OR TRANSFERS ANY RIGHTS TO REPRODUCE, USE, OR DISCLOSE, IN WHOLE OR IN PART, DATA CONTAINED HEREIN FOR ANY PURPOSE, WITHOUT THE WRITTEN PERMISSION OF WESTECH ENGINEERING, INC. DATE C:\Vault\Design\Jobs\22800\22838B Smoky Canyon\2001-GENERAL ARRANGEMENT, RO SYSTEM.idw 12'-21 8" APPROXIMATE OVERALL HEIGHT 11'-9" E B H C D A G F 4'-0" MINIMUM CLEARANCE TYPICAL 1" J 2'-101 4" 11'-97 8" 14'-33 8" 16'-815 16" E B H C 14'-6 5 16" 15'-7 5 16" F G 1'-1 7 16" 5'-53 4" B H C D A G F 11 3 16" E 1 3 4" 6'-05 8" 3'-43 4" J 1'-11 7 16" J 1'-11 2" 1'-911 16" PRELIMINARY NOT FOR CONSTRUCTION ---PAGE BREAK--- SECTION A-A - ANCHOR BOLT LAYOUT (FROM SHEET 2) BACK REV - SHEET DOCUMENT NUMBER 2001 3 OF 3 TITLE GENERAL ARRANGEMENT, RO SKID RO SYSTEM 24 VESSELS VO00 DESIGNER CHECKER APPROVER THIS DRAWING IS PROPERTY OF WESTECH ENGINEERING, INC. AND IS TRANSMITTED IN CONFIDENCE. NEITHER RECEIPT NOR POSSESSION CONFERS OR TRANSFERS ANY RIGHTS TO REPRODUCE, USE, OR DISCLOSE, IN WHOLE OR IN PART, DATA CONTAINED HEREIN FOR ANY PURPOSE, WITHOUT THE WRITTEN PERMISSION OF WESTECH ENGINEERING, INC. DATE C:\Vault\Design\Jobs\22800\22838B Smoky Canyon\2001-GENERAL ARRANGEMENT, RO SYSTEM.idw n3 4" HOLES FOR Ø5 8" ANCHOR BOLTS (PROVIDED BY RSCI) 11'-3" 11'-3" 31 2" 5'-5" 31 2" 4 PRELIMINARY NOT FOR CONSTRUCTION ---PAGE BREAK--- GFH® DRY GRANULAR FERRIC HYDROXIDE MEDIA A PROVEN, SAFE, AND SIMPLE SOLUTION TO ARSENIC REMOVAL CHALLENGES Description In March of 2001, the US Environmental Protection Agency (EPA) issued its rule setting the arsenic primary drinking water maximum contaminant level (MCL) of 10 micrograms per liter, enforceable as of January 23, 2006. State guidance was provided in August of 2002 and since then, some states have adopted even lower limits, e.g., 5 micrograms per liter. Over the past decade, this regulation has prompted hundreds of municipalities to utilize numerous treatment technologies for the removal of arsenic. Among the various technologies available, the EPA Arsenic Treatment Technology Demonstration Program has shown iron-based media to be effective for arsenic removal. GFH® DRY Media is a specially designed adsorbent media based on granular ferric hydroxide. It is specifically designed for the removal of arsenic (arsenate (As+5) and arsenite (As+3)) from water and can remove other heavy metals as well. The arsenic removal requires no preconditioning or preoxidation. Applied in a downflow packed bed configuration, it is easily applied to municipal wellhead applications. Applications In addition to arsenic, GFH DRY Media has been demonstrated to provide removal of several othercontaminants, including: • Phosphate • Antimony • Copper System options GFH Media can be placed into parallel or series pressure vessel systems depending on the removal requirement. To apply GFH DRY Media, our Vantage® PTI Series systems are available in Simplex, Duplex, or Triplex configurations. These systems are preengineered, pre-assembled, and factory tested to minimize installation and startup time. Service and Disposal options For arsenic removal applications where the client cannot incur a capital expense for a treatment system, Evoqua offers integrated equipment and service combinations (temporary or permanent), thereby minimizing a plant’s capital investment and reducing overall space requirements. Temporary installations are also available through our mobile fleet, providing the ultimate flexibility to add or remove treatment capacity as your business grows or compliance limits change. This option also saves valuable manufacturing space while minimizing your maintenance and installation requirements. Once exhausted, spent GFH DRY Media can be disposed of via landfill and classified as a non-hazardous waste after passing a TCLP test. Evoqua can provide full media exchange services and disposal assistance in GFH DRY Media applications. GFH® GRANULAR FERRIC HYDROXIDE MEDIA ---PAGE BREAK--- 210 Sixth Avenue, Suite 3300, Pittsburgh, PA 15222 +1 (866) 926-8420 (toll-free) +1 (978) 614-7233 (toll) www.evoqua.com/remediation GFH and Vantage are trademarks of Evoqua Water Technologies LLC, its subsidiaries or affiliates, in some countries. All other trademarks are those of their respective owners. All information presented herein is believed reliable and in accordance with accepted engineering practices. Evoqua makes no warranties as to the completeness of this information. Users are responsible for evaluating individual product suitability for specific applications. Evoqua assumes no liability whatsoever for any special, indirect or consequential damages arising from the sale, resale or misuse of its products. © 2018 Evoqua Water Technologies LLC Subject to change without notice Features and Benefits • ANSI / NSF 61 Certified for use in Potable Water Applications. • Consistent removal of both arsenate and arsenite forms of arsenic, even during sudden changes in influent arsenic concentration. • Applications fully supported by Evoqua laboratory facilities to evaluate and tailor specific solutions to each application. • Standard systems using GFH® Media are designed for flows from 1 to 5,000 gpm and higher. Compact designs that require minimal operator attention. • Service based offerings reduce capital investment required. • Full service capabilities for spent media exchange and disposal available. • Low waste volume typical). • High arsenic capacity resulting in long media bed life and reduced frequency of media exchange. • Does not impact water pH. PHYSICAL PROPERTIES Particle Size 10 x 50 mesh / 315 x 2000 micron Bulk Density, backwashed (lb./ft3) 29 – 36 Chemical Composition Fe2O3 OPERATING CONDITIONS Operating pH Range 5.5 – 9.0 Recommended Contact Time 3.5 minutes minimum Backwash Rate (gpm/ft2) 5 - 7 Maximum Operating Temperature 140°F * Temperature limit of standard equipment. Contact your representative for higher temperature applications. ---PAGE BREAK--- All information presented herein is believed reliable and in accordance with accepted engineering practices. Evoqua makes no warranties as to completeness of information. Users are responsible for evaluating individual product suitability for specific applications. Evoqua assumes no liability whatsoever for any special, indirect or consequential damages arising from the sale, resale or misuse of its products. Evoqua reserves the right to change the specifications referred to in this literature at any time, without prior notice. Evoqua Water Technologies, Inc. Tel: [PHONE REDACTED] www.evoqua.com Page 1 of 2 [EMAIL REDACTED] Rev. 7 – 05/26/15 HP®1220SYS GAC ADSORPTION SYSTEM SPECIFICATION SUMMARY HP®1220SYS Liquid Phase Adsorption Systems are designed to treat a wide range of contaminated process streams. Piping and valves are configured for series, parallel, or vessel isolation flows. System includes GAC inlet and outlet piping, and backwash capabilities. The system consists of two adsorbers, with all piping, valves, and gauges assembled for ease of operation. The adsorbers are equipped with underdrains capable of maximum series flow rate of 1100 GPM. EACH VESSEL: Vessel 144” Side Shell Height 60” Overall Height …16’-4” Maximum Working Pressure 125 psi @ 140 °F Manway: Flanged at side shell 20” Elliptical type at head 14” x 18” Vessel Volume 7,520 gal. Carbon Capacity 20,000 lbs. Carbon Bed Volume-Typical (29.5 678 Ft3 Maximum Flow Rate 1100 GPM Empty Bed Contact Time 4.6 min/vessel @ 1100 GPM ASME Code Stamping YES Material Carbon Steel Supports Wide Flange Legs Lifting Lifting Lugs Seismic IBC Interior Surface Prep SSPC-SP5 Interior Surface Coating Plasite 4110 35 mil dft min Exterior Surface Primer Epoxy 3 mil min dft Exterior Surface Coating Urethane 3mil min dft Standard Color Desert Sand (#9225) CONNECTIONS: Inlet / Outlet 8” 150# ANSI Flanged Carbon Fill / Kamlock Backwash 8” Flanged Utility Water Kamlock ---PAGE BREAK--- All information presented herein is believed reliable and in accordance with accepted engineering practices. Evoqua makes no warranties as to completeness of information. Users are responsible for evaluating individual product suitability for specific applications. Evoqua assumes no liability whatsoever for any special, indirect or consequential damages arising from the sale, resale or misuse of its products. Evoqua reserves the right to change the specifications referred to in this literature at any time, without prior notice. Evoqua Water Technologies, Inc. Tel: [PHONE REDACTED] www.evoqua.com Page 2 of 2 [EMAIL REDACTED] UNDERDRAINS: External Ring Header 8” Sch. 40 Carbon Steel Screens 8 ea 316L Stainless Steel V-Wire Screens 4 ½” dia. x 10” VALVE ASSEMBLY AND PIPING: Piping: Process Piping 8” Schedule 40 Carbon Steel GAC Transfer Piping 4” Sch 40 Carbon Steel, Epoxy Lined Valves: Process 8” Butterfly, Cast Iron Body w/SS Disk, Gear Operator GAC Transfer 4” Flanged 316 Stainless Steel Ball Valve Drain/Wash 2” Bronze Ball Valve Sample Ports 1/2” Bronze Ball Valve SYSTEM WEIGHT: System Shipping weight (Two Vessels Piping & Manifold) 35,000 lbs. Carbon Weight 40,000 lbs. Operating Weight 160,000 lbs. FOR ADDITIONAL INFORMATION, PLEASE CONTACT YOUR NEAREST CARBON SERVICE BRANCH AT: [PHONE REDACTED] ---PAGE BREAK--- C0356937 Note: Additions shall not be made to this document without prior evaluation and acceptance by NSF International. NSF International 789 N. Dixboro Road, Ann Arbor, Michigan 48105-9723 USA 1-800-NSF-MARK / [PHONE REDACTED] www.nsf.org 1 of 1 OFFICIAL LISTING NSF International Certifies that the products appearing on this Listing conform to the requirements of This is the Official Listing recorded on September 5, 2017. Evoqua Water Technologies LLC 14250 Gannet Street La Mirada, CA 90638 Adsorption Media [PHONE REDACTED] NSF/ANSI Standard 61 - Drinking Water System Components - Health Effects [PHONE REDACTED] Facility: # 2 Germany Process Media Water Water Contact Contact Trade Designation Size Temp Material Certified for water treatment plant applications. This product has not been evaluated for point of use applications. GFH® DRY MEDIA .3 mm - 2 mm CLD 23 FEOH This product is to be rinsed following the procedures outlines below before start-up: Upwash with 10 bed volumes at a rate of 30 m/h to achieve an expansion of 60%. Forward rinse to waste at 20 m/h to settle the bed and ensure that all fine material has been removed prior to putting the adsorber into service. NOTE: ---PAGE BREAK--- ELEVATION VIEW SCALE 1/2" = 1' PLAN VIEW SCALE 1/2" = 1' 5 6 7 A 8 3 4 2 B 1 BAR = 1" AT PLOT SCALE STD: BORDER-1101-22X34D C INTL REF: D C:\RBFR_Vault\Standards\HP1020\HP1020SYS-CS-FX\HP1020SYS-CS-FX - SALES.idw DATE REV DATE DATE DESIGNER CHECKER COMPANY CONFIDENTIAL SCALE: FILE: MANAGER DATE TITLE CLIENT PROJECT CODE DRAWING SHEET ENGINEER THIS DOCUMENT AND ALL INFORMATION CONTAINED HEREIN ARE THE PROPERTY OF EVOQUA AND/OR ITS AFFILIATES. THE DESIGN CONCEPTS AND INFORMATION CONTAINED HEREIN ARE PROPRIETARY TO EVOQUA AND ARE SUBMITTED IN CONFIDENCE. THEY ARE NOT TRANSFERABLE AND MUST BE USED ONLY FOR THE PURPOSE FOR WHICH THE DOCUMENT IS EXPRESSLY LOANED. THEY MUST NOT BE DISCLOSED, REPRODUCED, LOANED OR USED IN ANY OTHER MANNER WITHOUT EXPRESS WRITTEN CONSENT OF EVOQUA. IN NO EVENT SHALL THEY BE USED IN ANY MANNER DETRIMENTAL TO THE INTEREST OF EVOQUA. ALL PATENT RIGHTS ARE RESERVED. UPON THE DEMAND OF EVOQUA, THIS DOCUMENT, ALONG WITH ALL COPIES AND EXTRACTS, AND ALL RELATED NOTES AND ANALYSES, MUST BE RETURNED TO EVOQUA OR DESTROYED, AS INSTRUCTED BY EVOQUA. ACCEPTANCE OF THE DELIVERY OF THIS DOCUMENT CONSTITUTES AGREEMENT TO THESE TERMS AND CONDITIONS. REV ECN DESCRIPTION DATE DWN CHKD APVD VESSEL 10FT 20K LB HP 125PSI SYS FX CS W3T257665 HP1020SYS-FX-CS OF 1/2" = 1' 1 1 0 SALES AJA 9/19/2014 Industry Inc. Red Bluff, Ca [PHONE REDACTED] ADDITIONAL NOTES: THIS DRAWING IS TO SHOW PIPING AND EQUIPMENT FOR CUSTOMER APPROVAL. ALL BUTTERFLY VALVES ARE DUCTILE IRON WITH STAINLESS TRIM, STAINLESS STEEL DISK. PROVIDE 316 STAINLESS STEEL SEPTA UNDER DRAIN SCREENS. VESSELS SHALL BE 125 PSI, ASME CODE. FINISH INTERIOR WITH PLASITE 4110, PREPARE AND APPLY STRICTLY IN ACCORDANCE WITH MANUFACTURERS RECOMMENDATIONS TO MEET NSF STD 61 REQUIREMENTS. PIPING MATERIALS SHALL MEET: CS PIPE ASTM A-53 GRADE B (ERW); CS FITTINGS SA-234, ASME B16.9; SS THREADED FITTINGS ASTM A-351; SS PIPE ASTM A-312; SS BW FITTINGS ASTM A-403; MI THREADED FITTINGS ASME B-16.3. FINISH EXTERIOR WITH CARBOGAURD 133 URTHANE COLOR TO BE 9225 CASHEW OVER CARBOLINE 888 RUST PREVENTATIVE EPOXY PRIMER APPLIED PER MFG. RECOMMENDATIONS. SYSTEM ESTIMATED SHIPPING WEIGHT: 35,000 LBS. GROUTING BY OTHERS IF REQUIRED. 10.) ± 2" TOLERANCE ON CONNECTION DIMENSIONS. 11.) DESIGNED FOR SEISMIC ZONE 4. 12.) SYSTEM PROCESS CONNECTIONS: 8" 150# RF FLANGES, BOLTS STRADDLE CENTERLINE AS SHOWN. 13.) CARBON CAPACITY: 20,000 LBS PER VESSEL. 14.) MAX. PROCESS FLOW: 1,100 GPM SERIES, 2,000 GPM PARALLEL. 15.) TYPICAL BACKWASH RATE (8X30 CARBON 55°F): 1000 GPM. 16.) OPERATING TEMPERATURE 140° F MAX. 6'-10" 10'-0" 10'-0" 26'-10" 11'-2" 8'-0" 1'-21 8" 20" FLANGED MANWAY 14" ELLIPTICAL MANWAY 4" FLANGED MEDIA INLET 1" FLANGED AIR/VAC RELEASE 2" FLANGED WASH DOWN NAME PLATE BRACKETS 4" FLANGED MEDIA OUT 18'-4" SAMPLE PORTS 8" FLANGED INLET 8" FLANGED OUTLET 8" FLANGED BACKWASH OUTLET ---PAGE BREAK--- FerrIX™ A33E is a hybrid ion exchange resin designed for selective removal of arsenic from water. This Engineering Bulletin includes information for removing arsenic in light commerical and residential applications using both point-of-use and whole home treatment systems with FerrIX A33E. ENGINEERING BULLETIN Arsenic removal for business and residential applications using FerrIX™ A33E ---PAGE BREAK--- Purolite is a leading manufacturer of ion exchange, catalyst, adsorbent and specialty resins. With global headquarters in the United States, Purolite is the only company that focuses 100% of its resources on the development and production of resin technology. Responding to the needs of our customers, Purolite has built the largest technical sales force in the industry, the widest variety of products and five strategically located Research and Development groups. Our ISO 9001 certified manufacturing facilities in the U.S.A, Romania and China combined with more than 40 sales offices in 30 countries ensure complete worldwide coverage. PREMIER PRODUCTS The quality and consistency of our products is fundamental to our performance. Throughout all Purolite plants, production is carefully controlled to ensure that our products meet the most stringent criteria, regardless of where they are produced. RELIABLE SERVICE We are technical experts and problem solvers. Reliable and knowledgeable, we understand the urgency required to keep businesses operating smoothly. Purolite employs the largest technical sales organization in the industry. INNOVATIVE SOLUTIONS Our continued investment in research & development means we are always perfecting and discovering innovative uses for ion exchange resins and adsorbents. We strive to make the impossible possible. INTRODUCTION Inside this Engineering Bulletin you will find an overview of Purolite resins that are effective in the removal of arsenic in business and residential applications. For more detailed information on any product or to find a product for an application not mentioned, please go to www.purolite.com or contact the Purolite office closest to you, listed on the back cover. BUSINESS AND RESIDENTIAL ARSENIC REMOVAL USING FERRIX™ A33E ---PAGE BREAK--- PUROLITE ENGINEERING BULLETIN BUSINESS AND RESIDENTIAL ARESENIC REMOVAL USING FERRIX™ A33E 1 FerrIX™ A33E Engineering Bulletin – Home and Business Applications Purolite arsenic treatment solution Arsenic is a semi-metal element in the periodic table. It is odorless and tasteless. It enters drinking water supplies from natural deposits in the earth or from agricultural and industrial practices. Arsenic has been linked to cancer of the bladder, lungs, skin, kidneys, nasal passages, liver, and prostate. Non-cancer effects can include thickening and discoloration of the skin, stomach pain, nausea, vomiting, diarrhea, numbness in hands and feet, partial paralysis and blindness. (United States Environmental Protection Agency, 2015). Health Canada has set the arsenic standard for drinking water at 0.010 parts per million (10 parts per billion) (0.010 mg/L) (Federal Provincial Territorial Committee on Drinking Water, 2006, p. 2) to protect consumers served by public water systems from the effects of long-term, chronic exposure to arsenic. FerrIX™ A33E FerrIX A33E is a proprietary hybrid ion exchange resin designed for selective removal of arsenic from water. This highly porous anion resin is infused with iron oxide to allow for fast and efficient adsorption of arsenic. The porous nature of the resin beads allows for maximum utilization of the infused iron. Iron oxide adsorption treatment for arsenic in groundwater is a common removal process that involves the chemical treatment of arsenic species. In the process, arsenic adsorbs onto the iron oxide to create larger particles that can be filtered out of the water stream. (“Ion oxide adsorption,” 2015) Water treatment systems incorporating FerrIX A33E resin are designed and operated using the same engineering guidelines as conventional ion exchange resins, and can be used in majority of existing lead-lag or parallel design configurations. This guide is meant to cover light commercial and residential applications for both point-of-use systems and whole home treatment systems. The superior strength of ion exchange beads means fines will not be generated during resin loading or the service cycle. Pressure drop will remain low and backwash will be minimized, reducing water loss and avoiding the discharge of arsenic laden fines to the sewer. • FerrIX A33E is certified to NSF/ANSI 61 Standard • FerrIX A33E is ideal for municipal water treatment plants as well as point-of-entry (POE) and point-of-use (POU) systems • FerrIX A33E is not hazardous according to OSHA 29 CFR 1910.120* Table 1 – Physical and chemical characteristics Polymer structure cross-linked with divinylbenzene Matrix structure Macroporous impregnated with iron oxide Physical form and appearance Brown spherical beads Whole beads (min.) 95% Bead size range 0.30 – 1.20 mm Bulk density 790 – 982 g/L (49 – 51 lbs/ft3) Operating Capacity** 0.5 – 4 g As/L Recommended contact time (minutes)*** 2.5 – 5 Specific service flow rate (typical) 20 – 24 BV/h up to 32 BV/h (2.5 – 3 gpm/ft3 up to 4 gpm/ft3) Minimum bed depth 1 m (36 in) Operating temperature (max.) 176°F (80°C) pH limits, operating 4.5 – 8.5 * Dispose of waste and residue in accordance with the requirement of local authorities . Will depend upon raw water composition and operating conditions. Typical contact time is 3 minutes. ---PAGE BREAK--- PUROLITE ENGINEERING BULLETIN BUSINESS AND RESIDENTIAL ARESENIC REMOVAL USING FERRIX™ A33E 2 FerrIX™ A33E Engineering Bulletin – Home and Business Applications Arsenic is one of the hardest ions to remove from water. It has a high molecular weight and there are many factors that will impact its removal from water. One of the main factors is that phosphate ions are very similar to arsenic ions, and compete for exchange sites. If the feed water has high levels of phospate, the capacity for aresnic removal will be much lower. Another factor that will affect the ability to remove arsenic from water is the feed pH. It is best to maintain close to neutral pH (~7pH) for arsenic removal applications. At lower pH levels, arsenic can become insoluable and lose its ionic charge. The levels of natural arsenic in water will vary from area to area with the highest levels in areas with very deep wells. Factors impacting arsenic removal capacity The capacity of all granular iron media (GIM) used for arsenic removal are significantly impacted by the following factors: • pH – increasing pH results in lower capacity • Phosphate – competes vigorously with arsenic for exchange sites on media • Silica – competes for exchange sites and can precipitate and/or bind with other foulants and block exchange sites • Vanadium – competes vigorously with arsenic for exchange sites • Other oxyanions (e.g. selenite, molybdate, antimonate, chromate) – will also have a negative effect on throughput capacity • Specific flow rate – gpm/ft3 of media or BV/h - higher specific flowrates results in earlier breakthrough and lower capacity • Empty Bed Contact Time (EBCT) – lower EBCT results in earlier breakthrough and lower capacity Essential data input It is important to gather as much information as possible on the system so that “surprises” can be avoided. For example, other anions and oxy-anions will compete with arsenic for removal by ion exchange resin so it is best to test for the following items prior to designing the treatment system: • Arsenic III (ppb) • Arsenic V (ppb) • Vanadium (measured to ppb levels, eg. 10 ppb ) • Phosphate (measured in ppb levels, eg. 30 ppb ) • Silica (ppm) • pH • Other oxyanions (e.g. molybdate, selenite, antimonate, uranyl—total all in ppb) • Peak flowrate - gpm or lpm • Water usage/day - GPD or LPD • Target maximum arsenic level in treated water Other factors that affect fouling, precipitation and oxidation, or that impact MCL limits: • Suspended solids • Total hardness • Iron / manganese • Chlorine or other oxidants • Nitrate • Microbiological count (if suspected to be a problem) Special notes The potential exists for nitrate dumping above the MCL due to residual anion capacity in the product. If nitrate in influent is above 5 ppm as N, contact your Purolite Technical Representative. ---PAGE BREAK--- PUROLITE ENGINEERING BULLETIN BUSINESS AND RESIDENTIAL ARESENIC REMOVAL USING FERRIX™ A33E 3 FerrIX™ A33E Engineering Bulletin – Home and Business Applications Equipment design parameters We suggest using a lead/lag equipment arrangement to reduce the likelihood of arsenic leakage upon resin exhaustion. The lead vessel will do the majority of the arsenic removal and the lag vessel will act as a polisher removing any amounts of leakage for the lead vessel. On exhaustion of the lead vessel, replace the lead with the lag vessel and put fresh resin in the lag position: Lead/lag design Other design parameters • 2 – 5 minutes contact time • < 6 gpm /ft3 flow rate 48 BV/h) • Bed depth > 30" (760 mm) • Distributor design for 16 – 50 mesh media (300 – 1,200 microns) • Sample ports at the inlet/inter-stage/outlet positions • Discount capacity for higher flow rate • Pre-filter for suspended solids to maintain < 1 NTU turbidity influent to the resin vessels • Consult with Purolite on further design details Typical breakthrough profile 0 2 4 6 8 10 12 14 16 0 10000 20000 30000 40000 50000 60000 70000 80000 90000 Arsenic Concentration, ppb Throughput, BV Arsenic Breakthrough - Typical Well Water Inlet Effluent ---PAGE BREAK--- PUROLITE ENGINEERING BULLETIN BUSINESS AND RESIDENTIAL ARESENIC REMOVAL USING FERRIX™ A33E 4 FerrIX™ A33E Engineering Bulletin – Home and Business Applications Pressure drop curve, Ferrix A33E Backwash expansion, Ferrix A33E References United States Environmental Protection Agency. (2015, November Chemical Contaminant Rules. Retrieved December 16, 2015, from http://www.epa.gov/dwreginfo/chemical-contaminant-rules Federal Provincial Territorial Committee on Drinking Water. (2006). It’s your health: Arsenic in drinking water (ISBN # 0- 662-36233-0). Retrieved from Health Canada website: http://www.hc-sc.gc.ca/hl-vs/alt_formats/pacrb-dgapcr/pdf/iyh- vsv/environ/arsenic-eng.pdf Ion oxide adsorption. (2015). In Wikipedia. Retrieved December 16, 2015, from All suggestions and recommendations given above concerning the use of Purolite products are based on tests and data believed to be reliable. However, as Purolite cannot control the use of its products by others, no guarantee is either expressed or implied by any such suggestion or recommendation by Purolite nor is any information contained in this leaflet to be construed as a recommendation to infringe any patent currently valid. 0 5 10 15 20 0 10 20 30 40 50 60 70 80 90 0 2 4 6 8 10 Linear Velocity, m/h Bed Expansion, % Linear Velocity, gpm/ft2 Ferrix A33E Backwash Expansion 50°F / 10°C 68°F / 20°C 0 5 10 15 20 25 30 35 40 0.0 10.0 20.0 30.0 40.0 50.0 60.0 0 0.5 1 1.5 2 2.5 3 0 2 4 6 8 10 12 14 16 18 Linear Velocity, m/h Pressure Drop, kPa/m Pressure Drop, psi/ft Linear Velocity, gpm/ft2 Ferrix A33E Pressure Drop 50°F / 10°C 68°F / 20°C ---PAGE BREAK--- FerrIX™ Application Questionnaire www.purolite.com 2018 Purolite. All rights reserved. P-000062-50PP-1118-R5-PCO General Information (TO BE COMPLETED BY SALES OFFICE) Date: Customer Address: Sales Office: Sales Person: Customer email: Customer: Customer phone: Essential water inlet requirements Application details Total hardness (ppm as CaCO3) Target arsenic leakage (ppb) Alkalinity (ppm as CaCO3) Daily water requirements (USG) T.S.S. (ppm) Flow rate (US gpm) T.D.S. (ppm) Vessel diameter pH Number of vessels Nitrate (ppm) Resin bed depth Arsenic V (ppb)* Pre-oxidation Yes No Arsenic III (ppb)* Chlorination Yes No Vanadium (ppb)* Pre-treatment Yes No Phosphate (ppb)* Silica (ppb)* Molybdate (ppb) Antimony (ppb) Selenium (ppb) Uranium (ppb) * Critical data input System limitations Design requirements Total arsenic > 2,000 ppb, vanadium > 100 ppb, phosphate > 1,000 ppb, silica > 90 ppm Minimum bed depth = 30" (36" is highly recommended.) pH > 9.0 or < 6.0 Two-vessel lead-lag design yields maximum capacity > 50 ppm of other oxyanions (Sb, Se, Mo, Ur) Flow rate = 2.5 – 4 US gpm/ft3 of resin > 5 ppm of nitrate Maximum operating temperature = 80°C (176°F) Contact your Purolite Representative for assistance if you exceed any of these parameters. ---PAGE BREAK--- Australia Brazil Canada China Czech Republic France Germany India Indonesia Italy Japan Jordan Kazakhstan Korea Malaysia Mexico Poland Romania Russia Singapore Slovak Republic South Africa Spain Taiwan Turkey UK Ukraine USA Uzbekistan For further information on Purolite® products & services visit www.purolite.com P-000062-50PP-1118-R5-PCO © 2018 Purolite All rights reserved. Americas 150 Monument Road Bala PA 19004 T +1 [PHONE REDACTED] T +1 [PHONE REDACTED] F +1 [PHONE REDACTED] [EMAIL REDACTED] Europe Llantrisant Business Park Llantrisant Wales, UK CF72 8LF T +44 1443 229334 F +44 1443 227073 [EMAIL REDACTED] Asia Pacific Room 707, C Section Huanglong Century Plaza No.3 Hangda Road Hangzhou, Zhejiang, China 310007 T +86 571 876 31382 F +86 571 876 31385 [EMAIL REDACTED] ---PAGE BREAK--- 2/20/2020 69 Appendix 3 – Decision Matrix ---PAGE BREAK--- Scoring Factors Pre-Distribution Blending Source Abandonment/ Replacement Source Reconfigureation/ Seasonal Use Coagulation/ Filtration Enhanced Lime Softening Reverse Osmosis Ion Exchange Activated Alumina Iron-Based Sorbents Ultrafiltration Point of Use Treatment Long Term Reliability1 (out of 15 pts) 7 15 7 15 15 15 12 12 15 15 13 Ease of Implementation2 (out of 25 pts) 22 10 25 15 10 20 15 15 15 20 5 Cost of Implementation3 (out of 30 pts) 12.2 20 30 9.4 17 12.8 8.7 9.2 9.2 14.5 9 Effectiveness4 (out of 30 pts) 20 15 18 25 20 30 20 20 25 27 15 Environmental Constraints (NEPA)5 (out of 10 pts) 10 5 8 10 10 10 10 10 10 10 10 Footprint Required/Land Use6 (out of 30 pts) 28 30 30 20 10 27 20 20 20 25 30 Scalability7 (out of 15 pts) 5 5 3 13 10 15 13 13 13 15 15 Effectiveness with AS- III8 (out of 20 pts) 5 5 10 0 5 10 5 0 10 5 5 Fundability9 (out of 10 pts) 10 10 2 10 10 10 10 10 10 10 5 Ease of Maintenance10 (out of 15 pts) 12 15 12 10 7 8 10 10 10 12 2 O&M Costs11 (out of 20 pts) 20 20 15 13 8 8 5 5 5 12 5 Operator Skill Required12 (out of 10 pts) 10 10 10 8 5 6 8 8 8 7 8 Power Demand13 (out of 20 pts) 20 15 20 15 18 10 15 15 15 14 20 Chemical Usage14 (out of 15 pts) 15 15 15 10 7 12 10 10 10 11 8 Waste Produced/Treatment Limitations15 (out of 25 pts) 25 25 25 18 15 15 10 10 15 15 22 Social Limitation16 (out of 10 pts) 10 5 1 10 10 10 10 10 10 10 3 Total = 231.2 220 231 201.4 177 218.8 181.7 177.2 200.2 222.5 175 Rank = 1 4 2 6 10 5 8 9 7 3 11 **Total Possible Points 300 Minden Town Arsenic Mitigation Decision Matrix ---PAGE BREAK--- 2/20/2020 71 Appendix 4 – Cost Estimates ---PAGE BREAK--- Ultrafiltration Cost Estimate Project: Arsenic Water Treatment Plant Owner: Minden Town Date: 07-Apr-20 Item Description Quantity Unit Unit Price Amount 1 LS 235,000 $ 235,000 $ Subtotal 235,000 $ 1 LS 15,000 $ 15,000 $ Clear and Grub 950 SY 1.00 $ 1,000 $ Re-Seeding 0 SY 2.00 $ - $ Subsurface Investigation 12 HR 250 $ 3,000 $ Material and Sampling Testing 1 LS 10,000 $ 10,000 $ Asphalt Pavement (2.5" AC over 6" Base) 300 SY 20 $ 6,000 $ Drivng and Parking Area Grading 0 CY 10 $ - $ Chain Link Fence 450 LF 20 $ 9,000 $ Main Access Gate 1 LS 4,000 $ 4,000 $ Side Access Gates 1 LS 2,000 $ 2,000 $ Retention Basin 1 LS 7,000 $ 7,000 $ Land Acquisition 2.5 Acre 260,000 $ 650,000 $ Electrical & SCADA 1 LS 75,000 $ 75,000 $ Subtotal 782,000 $ - $ Flow Meter Assembly 3 EA 3,500 $ 10,500 $ - $ Subtotal 10,500 $ - $ Static Mixer 1 LS 6,800 $ 6,800 $ Piping and Appurtenances 1 LS 3,000 $ 3,000 $ Subtotal 9,800 $ Pre-fab Metal Building (30'x80') 1 LS $360,000.00 360,000 $ MF Building Earthwork (nonrock) 200 CY 30 $ 6,000 $ 3 CY 30 $ 100 $ Chemical Spill Containtment Vault 1 LS 10,000 $ 10,000 $ Chemical Spill Containtment Vault Earthwork 10 CY 30 $ 300 $ Subtotal 376,400 $ Storm Water Pollution Prevention Engineer's Opinion of Probable Cost 2000 GPM Membrane Treatment Facility MOBILIZATION Mobilization SITE WORK INLINE STATIC MIXER MEMBRANE FILTRATION BUILDING Building Pump Earthwork ---PAGE BREAK--- Ultrafiltration Cost Estimate WesTech UF Equipment 1 LS 630,000 $ 630,000 $ Piping & Valving 1 LS 200,000 $ 200,000 $ Piping Installation 1 LS 500,000 $ 500,000 $ Pipe Supports 1 LS 4,500 $ 4,500 $ 1 LS 90,000 $ 90,000 $ Eyewash and shower station 1 EA 830 $ 800 $ Air Compressor 1 EA 5,500 $ 5,500 $ Distribution Pumps 3 EA 15,000 $ 45,000 $ Variable Frequency Drive 3 LS 15,000 $ 45,000 $ Flow Meter 1 EA 10,000 $ 10,000 $ House Water Booster Pump 1 LS 37,000 $ 37,000 $ Instrumentation 1 LS 1,000 $ 1,000 $ FeCl3 Tank 1 EA 9,500 $ 9,500 $ FeCl3 Pump Assembly 1 LS 14,330 $ 14,300 $ - $ - $ Sodium Hypochlorite Generation System 1 LS 236,000 $ 236,000 $ Sodium Hypochlorite Pump Assembly 1 LS 19,400 $ 19,400 $ Chlorine Analyzer 1 EA 5,000 $ 5,000 $ Eyewash and shower station 1 EA 830 $ 800 $ Chemical Secondary Containment 1 LS 5,000 $ 5,000 $ Subtotal 1,858,800 $ Subtotal - $ Backwash FEQ Tank Earthwork (nonrock) 25 CY 100 $ 2,500 $ - $ Backwash FEQ Tank Concrete w/Rebar 30 CY 925 $ 27,800 $ Backwash FEQ Tank Base Course 13 CY 15 $ 200 $ - $ Pressure Transmitter 1 EA 2,000 $ 2,000 $ Access Ladder 2 EA 2,000 $ 4,000 $ Mixer Platform 1 LS 10,000 $ 10,000 $ Mixer 1 LS 30,500 $ 30,500 $ 4" Valve plus Mueller Type B Post 1 EA 1,913 $ 1,900 $ 10" Valve plus Mueller Type B Post 1 EA 3,813 $ 3,800 $ Piping and Appurtenances 1 LS 12,000 $ 12,000 $ Subtotal 94,700 $ WTP Construction Subtotal $3,367,200 $505,000 MEMBRANE FILTRATION EQUIPMENT Electrical & Controls Distribution Pumps and House Water Chemical Room 15% Contingency BACKWASH FEQ TANK ---PAGE BREAK--- Ultrafiltration Cost Estimate Estimated Construction Subtotal $3,872,200 Engineering & Incidental Professional Services 15% of Construction Costs 581,000 $ Total Project Cost $10,251,800 ---PAGE BREAK--- Reverse Osmosis Cost Estimate Project: Arsenic Water Treatment Plant Owner: Minden Town Date: 07-Apr-20 Item Description Quantity Unit Unit Price Amount 1 LS 255,000 $ 255,000 $ Subtotal 255,000 $ 1 LS 15,000 $ 15,000 $ Clear and Grub 950 SY 1.00 $ 1,000 $ Re-Seeding 0 SY 2.00 $ - $ Subsurface Investigation 12 HR 250 $ 3,000 $ Material and Sampling Testing 1 LS 10,000 $ 10,000 $ Asphalt Pavement (2.5" AC over 6" Base) 300 SY 20 $ 6,000 $ Drivng and Parking Area Grading 0 CY 10 $ - $ Chain Link Fence 450 LF 20 $ 9,000 $ Main Access Gate 1 LS 4,000 $ 4,000 $ Side Access Gates 1 LS 2,000 $ 2,000 $ Retention Basin 0 LS 7,000 $ - $ Land Acquisition 2.5 Acre 260,000 $ 650,000 $ Electrical and SCADA 1 LS 75,000 $ 75,000 $ Subtotal 775,000 $ Flow Meter Assembly 3 EA 3,500 $ 10,500 $ - $ Subtotal 10,500 $ - $ Static Mixer 1 LS 6,800 $ 6,800 $ Piping and Appurtenances 1 LS 3,000 $ 3,000 $ Subtotal 9,800 $ Pre-fab Metal Building (30'x80') 1 LS $360,000.00 360,000 $ Building Earthwork (nonrock) 200 CY 30 $ 6,000 $ 3 CY 30 $ 100 $ Chemical Spill Containtment Vault 1 LS 10,000 $ 10,000 $ Chemical Spill Containtment Vault Earthwork 10 CY 30 $ 300 $ Subtotal 376,400 $ BURIED PIPING & VALVES INLINE STATIC MIXER MEMBRANE FILTRATION BUILDING Building Pump Earthwork Storm Water Pollution Prevention Engineer's Opinion of Probable Cost 2000 gpm RO Treatment Facility MOBILIZATION Mobilization SITE WORK ---PAGE BREAK--- Reverse Osmosis Cost Estimate WesTech's UF Equipment 1 LS 940,000 $ 940,000 $ Piping & Valving 1 LS 200,000 $ 200,000 $ Piping Installation 1 LS 500,000 $ 500,000 $ Pipe Supports 1 LS 4,500 $ 4,500 $ 1 LS 90,000 $ 90,000 $ Eyewash and shower station 1 EA 830 $ 800 $ Air Compressor 1 EA 5,500 $ 5,500 $ Distribution Pumps 3 EA 15,000 $ 45,000 $ Variable Frequency Drive 3 LS 15,000 $ 45,000 $ Flow Meter 1 EA 10,000 $ 10,000 $ House Water Booster Pump 1 LS 37,000 $ 37,000 $ Instrumentation 1 LS 1,000 $ 1,000 $ FeCl3 Tank 1 EA 9,500 $ 9,500 $ FeCl3 Pump Assembly 1 LS 14,330 $ 14,300 $ - $ - $ Sodium Hypochlorite Generation System 1 LS 236,000 $ 236,000 $ Sodium Hypochlorite Pump Assembly 1 LS 19,400 $ 19,400 $ Chlorine Analyzer 1 EA 5,000 $ 5,000 $ Eyewash and shower station 1 EA 830 $ 800 $ Chemical Secondary Containment 1 LS 5,000 $ 5,000 $ Subtotal 2,168,800 $ Subtotal - $ Backwash FEQ Tank Earthwork (nonrock) 55 CY 100 $ 5,500 $ - $ Backwash FEQ Tank Concrete w/Rebar 66 CY 925 $ 61,100 $ Backwash FEQ Tank Base Course 30 CY 15 $ 500 $ - $ Pressure Transmitter 1 EA 2,000 $ 2,000 $ Access Ladder 2 EA 2,000 $ 4,000 $ Mixer Platform 1 LS 10,000 $ 10,000 $ Mixer 1 LS 30,500 $ 30,500 $ 4" Valve plus Mueller Type B Post 1 EA 1,913 $ 1,900 $ 10" Valve plus Mueller Type B Post 1 EA 3,813 $ 3,800 $ Piping and Appurtenances 1 LS 12,000 $ 12,000 $ Subtotal 131,300 $ WTP Construction Subtotal $3,726,800 $559,000 15% Contingency BACKWASH FEQ TANK MEMBRANE FILTRATION EQUIPMENT Electrical & Controls Distribution Pumps and House Water Chemical Room ---PAGE BREAK--- Reverse Osmosis Cost Estimate Estimated Construction Subtotal $4,285,800 Engineering & Incidental Professional Services 15% of Construction Costs 214,000 $ Total Project Cost $10,298,400 ---PAGE BREAK--- Coagulation/Filtration Cost Estimate Project: Arsenic Water Treatment Plant Owner: Minden Town Date: 07-Apr-20 Item Description Quantity Unit Unit Price Amount 1 LS 295,000 $ 295,000 $ Subtotal 295,000 $ 1 LS 15,000 $ 15,000 $ Clear and Grub 950 SY 1.00 $ 1,000 $ Re-Seeding 0 SY 2.00 $ - $ Subsurface Investigation 12 HR 250 $ 3,000 $ Material and Sampling Testing 1 LS 10,000 $ 10,000 $ Asphalt Pavement (2.5" AC over 6" Base) 300 SY 20 $ 6,000 $ Drivng and Parking Area Grading 0 CY 10 $ - $ Chain Link Fence 450 LF 20 $ 9,000 $ Main Access Gate 1 LS 4,000 $ 4,000 $ Side Access Gates 1 LS 2,000 $ 2,000 $ Retention Basin 0 LS 7,000 $ - $ Land Acquisition 2.5 Acre 260,000 $ 650,000 $ Electrical and SCADA 1 LS 75,000 $ 75,000 $ Subtotal 775,000 $ Flow Meter Assembly 3 EA 3,500 $ 10,500 $ - $ Subtotal 10,500 $ - $ Static Mixer 1 LS 6,800 $ 6,800 $ Piping and Appurtenances 1 LS 3,000 $ 3,000 $ Subtotal 9,800 $ Pre-fab Metal Building (40'x100') 1 LS $600,000.00 600,000 $ Building Earthwork (nonrock) 200 CY 30 $ 6,000 $ 3 CY 30 $ 100 $ Chemical Spill Containtment Vault 1 LS 10,000 $ 10,000 $ Chemical Spill Containtment Vault Earthwork 10 CY 30 $ 300 $ Subtotal 616,400 $ BURIED PIPING & VALVES INLINE STATIC MIXER MEMBRANE FILTRATION BUILDING Building Pump Earthwork Storm Water Pollution Prevention Engineer's Opinion of Probable Cost 2000 GPM Pressure Filter Treatment Facility MOBILIZATION Mobilization SITE WORK ---PAGE BREAK--- Coagulation/Filtration Cost Estimate WesTech Pressure Filter Equipment 1 LS 1,050,000 $ 1,050,000 $ Piping & Valving 1 LS 275,000 $ 275,000 $ Piping Installation 1 LS 550,000 $ 550,000 $ Pipe Supports 1 LS 5,000 $ 5,000 $ 1 LS 90,000 $ 90,000 $ Eyewash and shower station 1 EA 830 $ 800 $ Air Compressor 1 EA 5,500 $ 5,500 $ Distribution Pumps 3 EA 15,000 $ 45,000 $ Variable Frequency Drive 3 LS 15,000 $ 45,000 $ Flow Meter 1 EA 10,000 $ 10,000 $ House Water Booster Pump 1 LS 37,000 $ 37,000 $ Instrumentation 1 LS 1,000 $ 1,000 $ FeCl3 Tank 1 EA 9,500 $ 9,500 $ FeCl3 Pump Assembly 1 LS 14,330 $ 14,300 $ - $ - $ Sodium Hypochlorite Generation System 1 LS 236,000 $ 236,000 $ Sodium Hypochlorite Pump Assembly 1 LS 19,400 $ 19,400 $ Chlorine Analyzer 1 EA 5,000 $ 5,000 $ Eyewash and shower station 1 EA 830 $ 800 $ Chemical Secondary Containment 1 LS 5,000 $ 5,000 $ Subtotal 2,404,300 $ Subtotal - $ Backwash FEQ Tank Earthwork (nonrock) 65 CY 100 $ 6,500 $ - $ Backwash FEQ Tank Concrete w/Rebar 80 CY 925 $ 74,000 $ Backwash FEQ Tank Base Course 34 CY 15 $ 500 $ - $ Pressure Transmitter 1 EA 2,000 $ 2,000 $ Access Ladder 2 EA 2,000 $ 4,000 $ Mixer Platform 1 LS 10,000 $ 10,000 $ Mixer 1 LS 30,500 $ 30,500 $ 4" Valve plus Mueller Type B Post 1 EA 1,913 $ 1,900 $ 10" Valve plus Mueller Type B Post 1 EA 3,813 $ 3,800 $ Piping and Appurtenances 1 LS 12,000 $ 12,000 $ Subtotal 145,200 $ WTP Construction Subtotal $4,256,200 $638,000 15% Contingency BACKWASH FEQ TANK MEMBRANE FILTRATION EQUIPMENT Electrical & Controls Distribution Pumps and House Water Chemical Room ---PAGE BREAK--- Coagulation/Filtration Cost Estimate Estimated Construction Subtotal $4,894,200 Engineering & Incidental Professional Services 15% of Construction Costs 245,000 $ Total Project Cost $10,937,800 ---PAGE BREAK--- Iron-Based Sorbent Cost Estimate Project: Arsenic Water Treatment Plant Owner: Minden Town Date: 07-Apr-20 Item Description Quantity Unit Unit Price Amount 1 LS 295,000 $ 295,000 $ Subtotal 295,000 $ 1 LS 15,000 $ 15,000 $ Clear and Grub 950 SY 1.00 $ 1,000 $ Re-Seeding 0 SY 2.00 $ - $ Subsurface Investigation 12 HR 250 $ 3,000 $ Material and Sampling Testing 1 LS 10,000 $ 10,000 $ Asphalt Pavement (2.5" AC over 6" Base) 300 SY 20 $ 6,000 $ Drivng and Parking Area Grading 0 CY 10 $ - $ Chain Link Fence 450 LF 20 $ 9,000 $ Main Access Gate 1 LS 4,000 $ 4,000 $ Side Access Gates 1 LS 2,000 $ 2,000 $ Retention Basin 0 LS 7,000 $ - $ Land Acquisition 2.5 Acre 260,000 $ 650,000 $ Electrical and SCADA 1 LS 75,000 $ 75,000 $ Subtotal 775,000 $ Flow Meter Assembly 3 EA 3,500 $ 10,500 $ - $ Subtotal 10,500 $ - $ Static Mixer 1 LS 6,800 $ 6,800 $ Piping and Appurtenances 1 LS 3,000 $ 3,000 $ Subtotal 9,800 $ Pre-fab Metal Building (40'x100') 1 LS $600,000.00 600,000 $ MF Building Earthwork (nonrock) 200 CY 30 $ 6,000 $ 3 CY 30 $ 100 $ Chemical Spill Containtment Vault 1 LS 10,000 $ 10,000 $ Chemical Spill Containtment Vault Earthwork 10 CY 30 $ 300 $ Subtotal 616,400 $ BURIED PIPING & VALVES INLINE STATIC MIXER MEMBRANE FILTRATION BUILDING Building Pump Earthwork Storm Water Pollution Prevention Engineer's Opinion of Probable Cost 2000 GPM Pressure Filter Treatment Facility MOBILIZATION Mobilization SITE WORK ---PAGE BREAK--- Iron-Based Sorbent Cost Estimate Evoqua's GFH Filter Equipment 1 LS 1,183,000 $ 1,183,000 $ Piping & Valving 1 LS 200,000 $ 200,000 $ Piping Installation 1 LS 500,000 $ 500,000 $ Pipe Supports 1 LS 4,500 $ 4,500 $ 1 LS 90,000 $ 90,000 $ Eyewash and shower station 1 EA 830 $ 800 $ Air Compressor 1 EA 5,500 $ 5,500 $ Distribution Pumps 3 EA 15,000 $ 45,000 $ Variable Frequency Drive 3 LS 15,000 $ 45,000 $ Flow Meter 1 EA 10,000 $ 10,000 $ House Water Booster Pump 1 LS 37,000 $ 37,000 $ Instrumentation 1 LS 1,000 $ 1,000 $ FeCl3 Tank 1 EA 9,500 $ 9,500 $ FeCl3 Pump Assembly 1 LS 14,330 $ 14,300 $ - $ - $ Sodium Hypochlorite Generation System 1 LS 236,000 $ 236,000 $ Sodium Hypochlorite Pump Assembly 1 LS 19,400 $ 19,400 $ Chlorine Analyzer 1 EA 5,000 $ 5,000 $ Eyewash and shower station 1 EA 830 $ 800 $ Chemical Secondary Containment 1 LS 5,000 $ 5,000 $ Subtotal 2,411,800 $ Subtotal - $ Backwash FEQ Tank Earthwork (nonrock) 65 CY 100 $ 6,500 $ - $ Backwash FEQ Tank Concrete w/Rebar 80 CY 925 $ 74,000 $ Backwash FEQ Tank Base Course 34 CY 15 $ 500 $ - $ Pressure Transmitter 1 EA 2,000 $ 2,000 $ Access Ladder 2 EA 2,000 $ 4,000 $ Mixer Platform 1 LS 10,000 $ 10,000 $ Mixer 1 LS 30,500 $ 30,500 $ 4" Valve plus Mueller Type B Post 1 EA 1,913 $ 1,900 $ 10" Valve plus Mueller Type B Post 1 EA 3,813 $ 3,800 $ Piping and Appurtenances 1 LS 12,000 $ 12,000 $ Subtotal 145,200 $ WTP Construction Subtotal $4,263,700 $640,000 15% Contingency BACKWASH FEQ TANK MEMBRANE FILTRATION EQUIPMENT Electrical & Controls Distribution Pumps and House Water Chemical Room ---PAGE BREAK--- Iron-Based Sorbent Cost Estimate Estimated Construction Subtotal $4,903,700 Engineering & Incidental Professional Services 15% of Construction Costs 245,000 $ Total Project Cost $10,947,300 ---PAGE BREAK--- Ion Exchange Cost Estimate Project: Arsenic Water Treatment Plant Owner: Minden Town Date: 07-Apr-20 Item Description Quantity Unit Unit Price Amount 1 LS 300,000 $ 300,000 $ Subtotal 300,000 $ 1 LS 15,000 $ 15,000 $ Clear and Grub 950 SY 1.00 $ 1,000 $ Re-Seeding 0 SY 2.00 $ - $ Subsurface Investigation 12 HR 250 $ 3,000 $ Material and Sampling Testing 1 LS 10,000 $ 10,000 $ Asphalt Pavement (2.5" AC over 6" Base) 300 SY 20 $ 6,000 $ Drivng and Parking Area Grading 0 CY 10 $ - $ Chain Link Fence 450 LF 20 $ 9,000 $ Main Access Gate 1 LS 4,000 $ 4,000 $ Side Access Gates 1 LS 2,000 $ 2,000 $ Retention Basin 0 LS 7,000 $ - $ Land Acquisition 2.5 Acre 260,000 $ 650,000 $ Electrical and SCADA 1 LS 75,000 $ 75,000 $ Subtotal 775,000 $ Flow Meter Assembly 3 EA 3,500 $ 10,500 $ - $ Subtotal 10,500 $ - $ Static Mixer 1 LS 6,800 $ 6,800 $ Piping and Appurtenances 1 LS 3,000 $ 3,000 $ Subtotal 9,800 $ Pre-fab Metal Building (40'x100') 1 LS $600,000.00 600,000 $ MF Building Earthwork (nonrock) 200 CY 30 $ 6,000 $ 3 CY 30 $ 100 $ Chemical Spill Containtment Vault 1 LS 10,000 $ 10,000 $ Chemical Spill Containtment Vault Earthwork 10 CY 30 $ 300 $ Subtotal 616,400 $ BURIED PIPING & VALVES INLINE STATIC MIXER MEMBRANE FILTRATION BUILDING Building Pump Earthwork Storm Water Pollution Prevention Engineer's Opinion of Probable Cost 2000 GPM Ion Exchange Treatment Facility MOBILIZATION Mobilization SITE WORK ---PAGE BREAK--- Ion Exchange Cost Estimate IX Filter Equipment 1 LS 1,263,000 $ 1,263,000 $ Piping & Valving 1 LS 200,000 $ 200,000 $ Piping Installation 1 LS 500,000 $ 500,000 $ Pipe Supports 1 LS 4,500 $ 4,500 $ 1 LS 90,000 $ 90,000 $ Eyewash and shower station 1 EA 830 $ 800 $ Air Compressor 1 EA 5,500 $ 5,500 $ Distribution Pumps 3 EA 15,000 $ 45,000 $ Variable Frequency Drive 3 LS 15,000 $ 45,000 $ Flow Meter 1 EA 10,000 $ 10,000 $ House Water Booster Pump 1 LS 37,000 $ 37,000 $ Instrumentation 1 LS 1,000 $ 1,000 $ FeCl3 Tank 1 EA 9,500 $ 9,500 $ FeCl3 Pump Assembly 1 LS 14,330 $ 14,300 $ - $ - $ Sodium Hypochlorite Generation System 1 LS 236,000 $ 236,000 $ Sodium Hypochlorite Pump Assembly 1 LS 19,400 $ 19,400 $ Chlorine Analyzer 1 EA 5,000 $ 5,000 $ Eyewash and shower station 1 EA 830 $ 800 $ Chemical Secondary Containment 1 LS 5,000 $ 5,000 $ Subtotal 2,491,800 $ Subtotal - $ Backwash FEQ Tank Earthwork (nonrock) 65 CY 100 $ 6,500 $ - $ Backwash FEQ Tank Concrete w/Rebar 80 CY 925 $ 74,000 $ Backwash FEQ Tank Base Course 34 CY 15 $ 500 $ - $ Pressure Transmitter 1 EA 2,000 $ 2,000 $ Access Ladder 2 EA 2,000 $ 4,000 $ Mixer Platform 1 LS 10,000 $ 10,000 $ Mixer 1 LS 30,500 $ 30,500 $ 4" Valve plus Mueller Type B Post 1 EA 1,913 $ 1,900 $ 10" Valve plus Mueller Type B Post 1 EA 3,813 $ 3,800 $ Piping and Appurtenances 1 LS 12,000 $ 12,000 $ Subtotal 145,200 $ WTP Construction Subtotal $4,348,700 $652,000 15% Contingency BACKWASH FEQ TANK MEMBRANE FILTRATION EQUIPMENT Electrical & Controls Distribution Pumps and House Water Chemical Room ---PAGE BREAK--- Ion Exchange Cost Estimate Estimated Construction Subtotal $5,000,700 Engineering & Incidental Professional Services 15% of Construction Costs 250,000 $ Total Project Cost $11,049,300 ---PAGE BREAK--- Activated Alumina Cost Estimate Project: Arsenic Water Treatment Plant Owner: Minden Town Date: 07-Apr-20 Item Description Quantity Unit Unit Price Amount 1 LS 300,000 $ 300,000 $ Subtotal 300,000 $ 1 LS 15,000 $ 15,000 $ Clear and Grub 950 SY 1.00 $ 1,000 $ Re-Seeding 0 SY 2.00 $ - $ Subsurface Investigation 12 HR 250 $ 3,000 $ Material and Sampling Testing 1 LS 10,000 $ 10,000 $ Asphalt Pavement (2.5" AC over 6" Base) 300 SY 20 $ 6,000 $ Drivng and Parking Area Grading 0 CY 10 $ - $ Chain Link Fence 450 LF 20 $ 9,000 $ Main Access Gate 1 LS 4,000 $ 4,000 $ Side Access Gates 1 LS 2,000 $ 2,000 $ Retention Basin 0 LS 7,000 $ - $ Land Acquisition 2.5 Acre 260,000 $ 650,000 $ Electrical and SCADA 1 LS 75,000 $ 75,000 $ Subtotal 775,000 $ Flow Meter Assembly 3 EA 3,500 $ 10,500 $ - $ Subtotal 10,500 $ - $ Static Mixer 1 LS 6,800 $ 6,800 $ Piping and Appurtenances 1 LS 3,000 $ 3,000 $ Subtotal 9,800 $ Pre-fab Metal Building (40'x100') 1 LS $600,000.00 600,000 $ MF Building Earthwork (nonrock) 200 CY 30 $ 6,000 $ 3 CY 30 $ 100 $ Chemical Spill Containtment Vault 1 LS 10,000 $ 10,000 $ Chemical Spill Containtment Vault Earthwork 10 CY 30 $ 300 $ Subtotal 616,400 $ BURIED PIPING & VALVES INLINE STATIC MIXER MEMBRANE FILTRATION BUILDING Building Pump Earthwork Storm Water Pollution Prevention Engineer's Opinion of Probable Cost 2000 GPM Ion Exchange Treatment Facility MOBILIZATION Mobilization SITE WORK ---PAGE BREAK--- Activated Alumina Cost Estimate Alumina Equipment 1 LS 1,213,000 $ 1,213,000 $ Piping & Valving 1 LS 200,000 $ 200,000 $ Piping Installation 1 LS 500,000 $ 500,000 $ Pipe Supports 1 LS 4,500 $ 4,500 $ 1 LS 90,000 $ 90,000 $ Eyewash and shower station 1 EA 830 $ 800 $ Air Compressor 1 EA 5,500 $ 5,500 $ Distribution Pumps 3 EA 15,000 $ 45,000 $ Variable Frequency Drive 3 LS 15,000 $ 45,000 $ Flow Meter 1 EA 10,000 $ 10,000 $ House Water Booster Pump 1 LS 37,000 $ 37,000 $ Instrumentation 1 LS 1,000 $ 1,000 $ FeCl3 Tank 1 EA 9,500 $ 9,500 $ FeCl3 Pump Assembly 1 LS 14,330 $ 14,300 $ - $ - $ Sodium Hypochlorite Generation System 1 LS 236,000 $ 236,000 $ Sodium Hypochlorite Pump Assembly 1 LS 19,400 $ 19,400 $ Chlorine Analyzer 1 EA 5,000 $ 5,000 $ Eyewash and shower station 1 EA 830 $ 800 $ Chemical Secondary Containment 1 LS 5,000 $ 5,000 $ Subtotal 2,441,800 $ Subtotal - $ Backwash FEQ Tank Earthwork (nonrock) 68 CY 100 $ 6,800 $ - $ Backwash FEQ Tank Concrete w/Rebar 80 CY 925 $ 74,000 $ Backwash FEQ Tank Base Course 34 CY 15 $ 500 $ - $ Pressure Transmitter 1 EA 2,000 $ 2,000 $ Access Ladder 2 EA 2,000 $ 4,000 $ Mixer Platform 1 LS 10,000 $ 10,000 $ Mixer 1 LS 30,500 $ 30,500 $ 4" Valve plus Mueller Type B Post 1 EA 1,913 $ 1,900 $ 10" Valve plus Mueller Type B Post 1 EA 3,813 $ 3,800 $ Piping and Appurtenances 1 LS 12,000 $ 12,000 $ Subtotal 145,500 $ WTP Construction Subtotal $4,299,000 $645,000 15% Contingency BACKWASH FEQ TANK MEMBRANE FILTRATION EQUIPMENT Electrical & Controls Distribution Pumps and House Water Chemical Room ---PAGE BREAK--- Activated Alumina Cost Estimate Estimated Construction Subtotal $4,944,000 Engineering & Incidental Professional Services 15% of Construction Costs 247,000 $ Total Project Cost $10,989,600 ---PAGE BREAK--- Blending Well 2 and 11 Cost Estimate Project: Arsenic Water Treatment Plant Owner: Minden Town Date: 07-Apr-20 Item Description Quantity Unit Unit Price Amount 1 LS 120,000 $ 120,000 $ Subtotal 120,000 $ 1 LS 35,000.00 $ 35,000 $ Subsurface Investigation 12 HR 250.00 $ 3,000 $ Material and Sampling Testing 1 LS 20,000.00 $ 20,000 $ Saw Cut Asphalt 3,170 LF 1.25 $ 4,000 $ 4" HMA trench Patch 616 SY 6.50 $ 4,000 $ Misc Electrical (Hookup Flow Meters) 1 LS 5,000 $ 5,000 $ Asphalt Milling and Roadwork 4,755 SQ.FT. 1.25 $ 5,900 $ Electrical & SCADA 1 LS 50,000 $ 50,000 $ - $ - $ - $ Subtotal 126,900 $ 18" PVC C-900 DR25 1,585 LF 65 $ 103,000 $ 18" Butterfly Valve 4 LS 1,500 $ 6,000 $ 18" Flow Meter Assembly 2 LS 6,000 $ 12,000 $ Misc Connections, Piping, Fittings, etc. 1 LS 8,000 $ 8,000 $ Imported Pipe Bedding 16,700 CU.YD. 50 $ 835,000 $ Imported Fill 13,900 CU.YD. 40 $ 556,000 $ - $ - $ - $ - $ - $ Subtotal 1,520,000 $ Pipeline Construction Subtotal $1,766,900 $265,000 Estimated Construction Subtotal $2,031,900 15% Contingency BURIED PIPING & VALVES Engineer's Opinion of Probable Cost Piping Well 2 to Well 11 for Blending MOBILIZATION Mobilization SITE WORK Traffic Control and Site Security ---PAGE BREAK--- Blending Well 2 and 11 Cost Estimate Engineering Incidental Professional Services 15% of Construction Costs 102,000 $ Total Project Cost $2,133,900 ---PAGE BREAK--- Blending Well 2 and 11 Cost Estimate Project: Arsenic Water Treatment Plant Owner: Minden Town Date: 07-Apr-20 Item Description Quantity Unit Unit Price Amount 1 LS 120,000 $ 120,000 $ Subtotal 120,000 $ 1 LS 35,000.00 $ 35,000 $ Subsurface Investigation 12 HR 250.00 $ 3,000 $ Material and Sampling Testing 1 LS 20,000.00 $ 20,000 $ Saw Cut Asphalt 3,170 LF 1.25 $ 4,000 $ 4" HMA trench Patch 616 SY 6.50 $ 4,000 $ Misc Electrical (Hookup Flow Meters) 1 LS 5,000 $ 5,000 $ Asphalt Milling and Roadwork 4,755 SQ.FT. 1.25 $ 5,900 $ Electrical & SCADA 1 LS 50,000 $ 50,000 $ - $ - $ - $ Subtotal 126,900 $ 18" PVC C-900 DR25 2,500 LF 65 $ 162,500 $ 18" Butterfly Valve 4 LS 1,500 $ 6,000 $ 18" Flow Meter Assembly 2 LS 6,000 $ 12,000 $ Misc Connections, Piping, Fittings, etc. 1 LS 8,000 $ 8,000 $ Imported Pipe Bedding 16,700 CU.YD. 50 $ 835,000 $ Imported Fill 13,900 CU.YD. 40 $ 556,000 $ - $ - $ - $ - $ - $ Subtotal 1,579,500 $ Pipeline Construction Subtotal $1,826,400 $274,000 Estimated Construction Subtotal $2,100,400 BURIED PIPING & VALVES 15% Contingency Engineer's Opinion of Probable Cost Piping Well 2 to Well 11 for Blending MOBILIZATION Mobilization SITE WORK Traffic Control and Site Security ---PAGE BREAK--- Blending Well 2 and 11 Cost Estimate Engineering Incidental Professional Services 15% of Construction Costs 105,000 $ Total Project Cost $2,205,400 ---PAGE BREAK--- Blending Well 5 and 11 Cost Estimate Project: Arsenic Water Treatment Plant Owner: Minden Town Date: 07-Apr-20 Item Description Quantity Unit Unit Price Amount 1 LS 220,000 $ 220,000 $ Subtotal 220,000 $ 1 LS 35,000.00 $ 35,000 $ Subsurface Investigation 12 HR 250.00 $ 3,000 $ Material and Sampling Testing 1 LS 20,000.00 $ 20,000 $ Saw Cut Asphalt 6,050 LF 1.25 $ 7,600 $ 4" HMA trench Patch 1,176 SY 6.50 $ 7,600 $ Misc Electrical (Hookup Flow Meters) 1 LS 5,000 $ 5,000 $ Asphalt Milling and Roadwork 9,075 SQ.FT. 1.25 $ 11,300 $ Electrical & SCADA 1 LS 50,000 $ 50,000 $ - $ - $ - $ Subtotal 139,500 $ 14" PVC C-900 DR25 3,025 LF 60 $ 181,500 $ 14" Butterfly Valve 4 LS 1,300 $ 5,200 $ 14" Flow Meter Assembly 2 LS 5,000 $ 10,000 $ Misc Connections, Piping, Fittings, etc. 1 LS 9,000 $ 9,000 $ Imported Pipe Bedding 31,800 CU.YD. 50 $ 1,590,000 $ Imported Fill 26,500 CU.YD. 40 $ 1,060,000 $ - $ - $ - $ - $ - $ Subtotal 2,855,700 $ Pipeline Construction Subtotal $3,215,200 $482,000 Estimated Construction Subtotal $3,697,200 BURIED PIPING & VALVES 15% Contingency Engineer's Opinion of Probable Cost Piping Well 5 to Well 11 for Blending MOBILIZATION Mobilization SITE WORK Traffic Control and Site Security ---PAGE BREAK--- Blending Well 5 and 11 Cost Estimate Engineering Incidental Professional Services 15% of Construction Costs 185,000 $ Total Project Cost $3,882,200 ---PAGE BREAK--- Blending Well 7 and 8 Cost Estimate Project: Arsenic Water Treatment Plant Owner: Minden Town Date: 07-Apr-20 Item Description Quantity Unit Unit Price Amount 1 LS 136,500 $ 136,500 $ Subtotal 136,500 $ 1 LS 35,000.00 $ 35,000 $ Subsurface Investigation 12 HR 250.00 $ 3,000 $ Material and Sampling Testing 1 LS 20,000.00 $ 20,000 $ Saw Cut Asphalt 3,700 LF 1.25 $ 4,600 $ 4" HMA trench Patch 719 SY 6.50 $ 4,700 $ Misc Electrical (Hookup Flow Meters) 1 LS 5,000 $ 5,000 $ Asphalt Milling and Roadwork 5,550 SQ.FT. 1.25 $ 6,900 $ Electrical & SCADA 1 LS 50,000 $ 50,000 $ - $ - $ - $ Subtotal 129,200 $ 14" PVC C-900 DR25 1,850 LF 60 $ 111,000 $ 14" Butterfly Valve 4 LS 1,300 $ 5,200 $ 14" Flow Meter Assembly 2 LS 5,000 $ 10,000 $ Misc Connections, Piping, Fittings, etc. 1 LS 8,000 $ 8,000 $ Imported Pipe Bedding 19,500 CU.YD. 50 $ 975,000 $ Imported Fill 16,200 CU.YD. 40 $ 648,000 $ - $ - $ - $ - $ - $ Subtotal 1,757,200 $ Pipeline Construction Subtotal $2,022,900 $303,000 Estimated Construction Subtotal $2,325,900 BURIED PIPING & VALVES 15% Contingency Engineer's Opinion of Probable Cost Piping Well 5 to Well 11 for Blending MOBILIZATION Mobilization SITE WORK Traffic Control and Site Security ---PAGE BREAK--- Blending Well 7 and 8 Cost Estimate Engineering Incidental Professional Services 15% of Construction Costs 116,000 $ Total Project Cost $2,441,900 ---PAGE BREAK--- Blending Well 7 and 9 Cost Estimate Project: Arsenic Water Treatment Plant Owner: Minden Town Date: 07-Apr-20 Item Description Quantity Unit Unit Price Amount 1 LS 136,500 $ 136,500 $ Subtotal 136,500 $ 1 LS 35,000.00 $ 35,000 $ Subsurface Investigation 12 HR 250.00 $ 3,000 $ Material and Sampling Testing 1 LS 20,000.00 $ 20,000 $ Saw Cut Asphalt 3,700 LF 1.25 $ 4,600 $ 4" HMA trench Patch 719 SY 6.50 $ 4,700 $ Misc Electrical (Hookup Flow Meters) 1 LS 5,000 $ 5,000 $ Asphalt Milling and Roadwork 14,430 SQ.FT. 1.25 $ 18,000 $ Electrical & SCADA 1 LS 50,000 $ 50,000 $ - $ - $ - $ Subtotal 140,300 $ 14" PVC C-900 DR25 4,810 LF 60 $ 288,600 $ 14" Butterfly Valve 4 LS 1,300 $ 5,200 $ 14" Flow Meter Assembly 2 LS 5,000 $ 10,000 $ Misc Connections, Piping, Fittings, etc. 1 LS 8,000 $ 8,000 $ Imported Pipe Bedding 50,600 CU.YD. 50 $ 2,530,000 $ Imported Fill 42,100 CU.YD. 40 $ 1,684,000 $ - $ - $ - $ - $ - $ Subtotal 4,525,800 $ Pipeline Construction Subtotal $4,802,600 $720,000 Estimated Construction Subtotal $5,522,600 BURIED PIPING & VALVES 15% Contingency Engineer's Opinion of Probable Cost Piping Well 5 to Well 11 for Blending MOBILIZATION Mobilization SITE WORK Traffic Control and Site Security ---PAGE BREAK--- Blending Well 7 and 9 Cost Estimate Engineering Incidental Professional Services 15% of Construction Costs 276,000 $ Total Project Cost $5,798,600 ---PAGE BREAK--- Blending Well 7, 8 and 9 Cost Estimate Project: Arsenic Water Treatment Plant Owner: Minden Town Date: 07-Apr-20 Item Description Quantity Unit Unit Price Amount 1 LS 355,000 $ 355,000 $ Subtotal 355,000 $ 1 LS 35,000.00 $ 35,000 $ Subsurface Investigation 12 HR 250.00 $ 3,000 $ Material and Sampling Testing 1 LS 20,000.00 $ 20,000 $ Saw Cut Asphalt 9,800 LF 1.25 $ 12,300 $ 4" HMA trench Patch 1,906 SY 6.50 $ 12,400 $ Misc Electrical (Hookup Flow Meters) 1 LS 5,000 $ 5,000 $ Asphalt Milling and Roadwork 14,700 SQ.FT. 1.25 $ 18,400 $ Electrical & SCADA 1 LS 50,000 $ 50,000 $ - $ - $ - $ Subtotal 156,100 $ 14" PVC C-900 DR25 4,900 LF 60 $ 294,000 $ 14" Butterfly Valve 8 LS 1,300 $ 10,400 $ 14" Flow Meter Assembly 3 LS 5,000 $ 15,000 $ Misc Connections, Piping, Fittings, etc. 1 LS 10,000 $ 10,000 $ Imported Pipe Bedding 51,500 CU.YD. 50 $ 2,575,000 $ Imported Fill 42,900 CU.YD. 40 $ 1,716,000 $ - $ - $ - $ - $ - $ Subtotal 4,620,400 $ Pipeline Construction Subtotal $5,131,500 $770,000 Estimated Construction Subtotal $5,901,500 BURIED PIPING & VALVES 15% Contingency Engineer's Opinion of Probable Cost Piping Well 5 to Well 11 for Blending MOBILIZATION Mobilization SITE WORK Traffic Control and Site Security ---PAGE BREAK--- Blending Well 7, 8 and 9 Cost Estimate Engineering Incidental Professional Services 15% of Construction Costs 295,000 $ Total Project Cost $6,196,500 ---PAGE BREAK--- 2/20/2020 102 Appendix 5 – Arsenic Data for Minden Town’s Wells ---PAGE BREAK--- Well 2 Well 3 Well 4 Well 5 Well 7 Well 8 Well 9 Well 10 Well 11 Jun-92 7 May-98 10 Jun-98 Jul-98 Aug-98 10 Sep-98 Oct-98 Nov-98 Dec-98 Jan-99 Feb-99 Mar-99 Apr-99 May-99 Jun-99 Jul-99 Aug-99 Sep-99 Oct-99 Nov-99 Dec-99 Jan-00 Feb-00 Mar-00 Apr-00 May-00 Jun-00 3 10 7.8 Jul-00 7 10 Aug-00 Sep-00 Oct-00 Nov-00 Dec-00 Jan-01 Feb-01 Mar-01 Apr-01 May-01 Jun-01 Jul-01 Aug-01 Sep-01 Oct-01 Nov-01 Dec-01 Jan-02 Feb-02 Mar-02 Apr-02 May-02 Jun-02 ---PAGE BREAK--- Well 2 Well 3 Well 4 Well 5 Well 7 Well 8 Well 9 Well 10 Well 11 Jul-02 Aug-02 5 8 8 Sep-02 Oct-02 Nov-02 Dec-02 Jan-03 Feb-03 Mar-03 Apr-03 May-03 Jun-03 Jul-03 12 Aug-03 Sep-03 Oct-03 Nov-03 Dec-03 Jan-04 Feb-04 Mar-04 Apr-04 May-04 Jun-04 Jul-04 10 Aug-04 Sep-04 Oct-04 Nov-04 Dec-04 Jan-05 Feb-05 Mar-05 Apr-05 May-05 Jun-05 8 Jul-05 Aug-05 Sep-05 Oct-05 Nov-05 12 Dec-05 Jan-06 Feb-06 Mar-06 Apr-06 11 12 May-06 Jun-06 Jul-06 8 Aug-06 11 8 9 Sep-06 ---PAGE BREAK--- Well 2 Well 3 Well 4 Well 5 Well 7 Well 8 Well 9 Well 10 Well 11 Oct-06 9 10 Nov-06 Dec-06 Jan-07 Feb-07 10 12 Mar-07 10 10 Apr-07 May-07 Jun-07 10 8 Jul-07 Aug-07 Sep-07 Oct-07 Nov-07 Dec-07 Jan-08 Feb-08 Mar-08 10 8 8 Apr-08 8 May-08 4 7 9 12 Jun-08 Jul-08 7 8.6 Aug-08 9.25 Sep-08 9 Oct-08 7 8 Nov-08 9 Dec-08 9 Jan-09 9 9 Feb-09 10 Mar-09 10 Apr-09 9 May-09 9 Jun-09 9 Jul-09 7 4 8 10 Aug-09 9 Sep-09 8 Oct-09 7 8 Nov-09 Dec-09 9 Jan-10 8 Feb-10 8 12 Mar-10 10 9 Apr-10 9 May-10 9 Jun-10 8 7 4 7 9 Jul-10 8 Aug-10 9 Sep-10 7 Oct-10 7 Nov-10 Dec-10 ---PAGE BREAK--- Well 2 Well 3 Well 4 Well 5 Well 7 Well 8 Well 9 Well 10 Well 11 Jan-11 Feb-11 Mar-11 Apr-11 May-11 Jun-11 Jul-11 Aug-11 7 4 8 7 8 Sep-11 Oct-11 Nov-11 Dec-11 Jan-12 Feb-12 Mar-12 Apr-12 11 May-12 7 3 Jun-12 8.5 9 8 10 Jul-12 4 7 9 Aug-12 7 9.5 9 Sep-12 Oct-12 7 8 Nov-12 6 Dec-12 9 Jan-13 10 9 Feb-13 10 Mar-13 13 Apr-13 9 May-13 10 9 Jun-13 8 4 7 9 Jul-13 8 9 Aug-13 9 Sep-13 Oct-13 Nov-13 6 7 Dec-13 Jan-14 10 8 Feb-14 11 Mar-14 9 7 Apr-14 8 12 May-14 12 Jun-14 12 3 7 6 9 Jul-14 7 11 9 Aug-14 8 Sep-14 8 Oct-14 9 Nov-14 6 9 Dec-14 9 Jan-15 9 Feb-15 Mar-15 10 8 ---PAGE BREAK--- Well 2 Well 3 Well 4 Well 5 Well 7 Well 8 Well 9 Well 10 Well 11 Apr-15 8 May-15 9 Jun-15 8 9 Jul-15 Aug-15 3 7 6 10 Sep-15 8 11 9 Oct-15 9 Nov-15 3 9 Dec-15 10 10 Jan-16 10 9 Feb-16 8 Mar-16 8 Apr-16 9 May-16 9 4 Jun-16 7 9 Jul-16 9 7 8 Aug-16 3 8 Sep-16 7 7 8 Oct-16 8 Nov-16 8 7 Dec-16 8 7 9 Jan-17 11 7 Feb-17 8 Mar-17 8 Apr-17 7 May-17 7 Jun-17 8 9 Jul-17 8.6 8 Aug-17 8 Sep-17 8 8 Oct-17 7 Nov-17 7 Dec-17 7 7 Jan-18 5 7 Feb-18 7 Mar-18 7 Apr-18 4 7 May-18 7 Jun-18 8 Jul-18 10 16 8 Aug-18 8 Sep-18 8 Oct-18 8 7 Nov-18 7 Dec-18 6 Jan-19 5 6 Feb-19 7 Mar-19 7 Apr-19 10 6 7 4 May-19 7 7 Jun-19 8 3 8 ---PAGE BREAK--- Well 2 Well 3 Well 4 Well 5 Well 7 Well 8 Well 9 Well 10 Well 11 Jul-19 7 8 Aug-19 12 8 Sep-19 8 Oct-19 7 7 Nov-19 7 Dec-19 6 Jan-20 9 6 Feb-20 7 Mar-20 7 Apr-20 5 7 May-20 9 Jun-20 7 3 6 7 8.5 7 6 4 # of Data Points 53 13 21 17 12 126 3 2 3 Average 7.9 4.4 7.8 7.8 10.3 8.5 7.0 7.5 4.0 75th Percentile 9 4 8 9 11 9 7 8.25 4 Median 8 4 7 8 10 8 7 7.5 4 MCL 10 10 10 10 10 10 10 10 10 Minden's Target 7 7 7 7 7 7 7 7 7