Snow Removal Wastewater Disposal Alternatives (State Job Number ) Christopher M. Miller, Ph.D., P.E. William H. Schneider IV, Ph.D., P.E.

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Snow Removal Wastewater Disposal Alternatives (State Job Number 134629) Christopher M. Miller, Ph.D., P.E.

1 Snow Removal Wastewater Disposal Alternatives (State Job Number ) Christopher M. Miller, Ph.D., P.E. William H. Schneider IV, Ph.D., P.E. Department of Civil Engineering University of Akron January 10, 2014

2 Acknowledgements ODOT Research Technical Committee Jamie Hendershot (District 10 Highway Management Administrator) Hans Gucker (Central Office) Tim Killeen (Formerly Central Office, now Ohio EPA) ODOT Research Office Other ODOT Personnel Paul Ensinger (District 4 Roadway Services Manager) Mark Griffiths (Stark County Garage Manager) 24 Other County Garage Managers UA Graduate Students Marla Kennedy Sarah Sullivan Heather Parker Phil Custer Mufuta Tshimanga 2

prevent corrosion Snow removal waste water generated during routine washing of salt trucks

3 Research Need ODOT maintains ~240 maintenance facilities in Ohio Many garages lack access to sanitary sewer (~80, mostly outposts) Salt trucks washed frequently during winter to prevent corrosion Snow removal waste water generated during routine washing of salt trucks contains: Suspended solids Dissolved solids Heavy metals (very limited data) Oil and grease 3

4 Previous Research 1. Discharging wash water directly to surface water with an approved NPDES permit (Virginia Transportation Research Council, 2004, 2006) Would require desalination; RO pilot testing was ineffective 2. Reuse the wash water for the production of brine (Alleman, 2004, Virginia Transportation Research Council, 2008). After treatment with an oil/water separator and settling tank, wash water could be converted to brine to be used as part of winter maintenance program Could result in reduced material costs and disposal costs Applicability depends on wash water quality and regulations Heavy metals testing not conducted 4

wash water is unknown The cost of wash water management is

5 ODOT Research Problem Current disposal costs can be high The volume of wash water generated is unknown The quality of truck wash water is unknown The cost of wash water management is unknown Cost effective, sustainable wash water management strategies are needed 5

practice for handling snow removal wastewater in Ohio Assess commercially viable

6 Project Objectives Evaluate the current state of the practice for handling snow removal wastewater for states outside of Ohio Evaluate the current state of the practice for handling snow removal wastewater in Ohio Assess commercially viable solutions for handling snow removal wastewater and provide a best management practices recommendation 6

7 Project Tasks Phase I ( ) 1. Assess current wash water management strategies across the nation 2. Establish current practices for managing truck wash water in Ohio 3. Identify viable alternatives for the management of truck wash water 4. Evaluate cost of alternative strategies 5. Meet with ODOT technical liaisons 6. Develop an evaluation and calculation matrix to assess costs 7. Make preliminary recommendations Phase II ( ) 8. Update the cost analysis tool 9. Evaluate wash water quality at an additional 22 locations across the state 10. Develop wash water quality models 11. Conduct pilot testing using selected filtration media and assess effectiveness and efficiency 12. Make final recommendation 7

8 Research Sequence Identify Management Strategies Literature Review Current practices outside Ohio Current practices in Ohio Wash water volume Preliminary list of options developed Wash water quality Bench scale testing Pilot scale testing Evaluate viability of strategies Final list of viable management strategies Determine costs Develop cost analysis tool Develop predictive water quality models 8

9 Wash Water Management Outside Ohio Seventeen state DOTs were interviewed to identify wash water management strategies. Four states are currently reusing wash water for brine or truck washing after varying levels of treatment. Many states reported using holding tanks for truck wash water management. Seven states have tried reusing wash water for brine or truck washing, but discontinued due to issues with corrosion or water quality. None of the states interviewed reported monitoring for heavy metals. 9

leach field, storm sewer, or holding tank Current management costs: Range from $0.05/gallon to $0.

10 Wash Water Management - Ohio Many garages lack sanitary sewer: 1 District Garage, 12 County Garages, and 66 Outpost Garages Current management strategies: Reuse (Henry and Meigs Counties) Disposal in leach field, storm sewer, or holding tank Current management costs: Range from $0.05/gallon to $0.54/gallon. Depend on whether wash water is hauled using ODOT equipment and personnel or a contractor. 10

11 Viable Management Strategies 18 potential strategies identified Each of these strategies was evaluated for technical feasibility and ease of implementation at ODOT facilities List narrowed to six (more on this later - Cost Analysis Tool) 11

12 ODOT Non-Sewer Volume Assessment An estimated 3.8 million gallons of wash water (based on survey and water use records) are generated at garages lacking access to sanitary sewer An average of 6.5 million gallons of brine are used by ODOT annually so demand for reuse exceeds supply! 12

Truck Wash Water Quality Sampling Wash water quality assessed over two winter seasons Winter 2011-2012 Three sample locations

13 Truck Wash Water Quality Sampling Wash water quality assessed over two winter seasons Winter Three sample locations Winter sample locations One location in each district Sampling effort resulting in 10,223 individual measurements! 13

Garage Sampling Protocol (2012-2013) Samples were analyzed for 17 heavy metal and 10

14 Garage Sampling Protocol ( ) Samples were analyzed for 17 heavy metal and 10 nonmetal parameters Samples were collected throughout the duration of wash events 14

15 Truck Wash Water Quality Overview Most garages exceeded reuse and disposal guidelines for some sample parameters Parameters of concern are copper, zinc, iron, lead, oil&grease, and TSS Only one garage with results below reuse and disposal guidelines 15

16 Disposal and Reuse Parameter Details Percent of garage medians and all 253 samples exceeding reuse limits and local disposal guidance % of Garages Exceeding Local Disposal Guidance Garage Medians % of Garages Exceeding Reuse Limit % of Samples Exceeding Local Disposal Guidance All 253 Samples % of Samples Exceeding Reuse Limit Parameter Copper Iron Zinc Lead TSS* Oil & Grease* Note: *only 89 of the 253 samples were tested for this parameter. Therefore the percentage is out of 89 not 253. Based on total metal concentrations. 16

17 Wash Water Quality Variability Copper concentrations were measured in samples collected at the beginning, middle, and end of the wash cycle Results showed a generally decreasing trend in copper concentration through the wash cycle Results for Allen County. Note: Total copper concentration is logarithmic scale. 17

$not meet reuse limits Particulate metal concentrations were a significant fraction of the total metal concentration for the traffic metals (Cu, Zn, Ni, Cr, Pb, and Fe) Wash water quality is highly$

18 Truck Wash Water Quality Summary Metals concentrations were compared to reuse limits and disposal guidelines Results showed that very few samples exceeded disposal guidelines, but many samples did not meet reuse limits Particulate metal concentrations were a significant fraction of the total metal concentration for the traffic metals (Cu, Zn, Ni, Cr, Pb, and Fe) Wash water quality is highly variable due to roadway exposure, mixing, and performance of the oil-water separator 18

re-use limit The model for zinc showed that as copper and iron increase, so does the likelihood that the total zinc will be above the

19 Wash Water Quality Modeling Four binary logistic regression models were developed The total copper model results show as the concentrations of chromium, nickel, zinc and total dissolved solids increase so does the likelihood for failing to meet the copper re-use limit The model for zinc showed that as copper and iron increase, so does the likelihood that the total zinc will be above the reuse limit Model results point to importance of TDS and turbidity, which may be indicative of oil-water separator performance and/or truck cleanliness 19

Wash Water Treatment Bench Testing Bench scale studies were conducted to assess the effectiveness of four different filtration media for metals removal Results indicated that

20 Wash Water Treatment Bench Testing Bench scale studies were conducted to assess the effectiveness of four different filtration media for metals removal Results indicated that media could reduce heavy metal concentrations MAR Systems (Cleveland, OH) Sorbster media performed significantly better than the others, selected for pilot study MAR Media 20

Wash Water Treatment - Pilot Testing Large

21 Wash Water Treatment - Pilot Testing Large scale pilot study was conducted using the Mar System Sorbster media; pilot unit was housed at UA ~ 3,000 gallons of wash water were collected from Stark County Garage and treated (4 different batches) 2,601 individual sample measurements 21

Pilot Study Results Multiple Sample Ports Average total metal removal efficiencies were 79%, 77%, 63%, and 94% for copper, zinc, iron, and lead, respectively

22 Pilot Study Results Multiple Sample Ports Average total metal removal efficiencies were 79%, 77%, 63%, and 94% for copper, zinc, iron, and lead, respectively Cumulative removal rate of total copper at each stage of the Stark County garage trials. Cumulative removal rate of total zinc at each stage of the Stark County garage trials. 22

23 Particulate Removal Assessment Settling Estimate Analysis showed that a large percentage of the total metals are present in the size fraction greater than 5 µm Filtration through a 5 µm filter yielded metal removal efficiencies of 82%, 60%, 87% and 76% for copper, zinc, iron and lead, respectively Particle settling estimates (at a temperature of 40 degrees Fahrenheit) showed an average settling time of 11.7 hours and 15.1 hours for 5 µm size particles of copper and zinc, respectively 5 µm 3 µm Metal 2m 3m 2m 3m Copper Zinc

24 Pilot Study Results Role of MAR Media The average total metal removal of the MAR Systems Sorbster media of wash water containing particles less than 5 µm was 46%, 68%, 59% and 79% for copper, zinc, iron and lead, respectively, which affirms the removal capabilities of the media 24

25 Wash Water Management Cost Analysis 1. Contributing cost factors were identified for each management option (including labor and fuel) Strategies Capital Annual Factor Value Factor Value Sanitary Sewer Construction Variable Disposal Variable Commercial Disposal Storage $30,000 Hauling and Disposal $0.30/gal Disposal at WWTP Storage $30,000 Water Quality Monitoring Hauling Disposal Disposal at ODOT Garage with Sewer Access Filtration and Disposal at ODOT Garage with Sewer Access Filtration and reuse at County Garage Storage $30,000 Water Quality Monitoring Hauling Disposal Storage Filtration Unit Storage Filtration Unit $30,000 $30,000 $30,000 $30,000 Water Quality Monitoring Hauling Disposal Media Replacement Water Quality Monitoring Hauling Media Replacement 2. Equivalent uniform annual costs were calculated : $1,385/yr Variable $0.05/gal $1,385/yr Variable $0.05/gal $1,385/yr Variable $0.05/gal $4,600/yr $1,385/yr Variable $4,600/yr i Annualized Capital Costs = Capital Costs 1+i n 1 +i Where: i = discount rate n = number of years Annualized Costs = Annualized Capital Costs + Annual Costs 25

26 Wash Water Management Cost Analysis Costs of alternative management strategies were compared with cost of tying into sanitary sewer to determine the break even point given specific number of trucks, events, and hauling dist. At $173,640, tying into the sanitary sewer was the most cost effective strategy $285,333, four of the five alternative strategies identified were more cost effective than tying into the sanitary sewer Garage with 12 trucks and 30 events; hauling distance = 55 miles (High Volume) 26

27 Wash Water Management Cost Analysis cont. For a lower volume garage, tying into the sanitary sewer is the most cost effective option when the capital cost is less than $95,025 When the sewer tie in cost is greater than $206,720, all five of the alternative strategies are more cost effective than tying into the sanitary sewer under the conditions of the analysis Garage with 3 trucks and 30 events; hauling distance = 55 miles (Low Volume) 27

28 Cost Analysis Tool An Excel based tool was developed to calculate management costs using user input site specific data The annual cost and potential savings versus sanitary sewer are calculated The tool can be used to assist in the selection of cost effective management strategies 28

Conclusions A comprehensive literature review and interview of seventeen other DOTs identified yielded six viable wash water management strategies, including disposal and reuse.

29 Conclusions A comprehensive literature review and interview of seventeen other DOTs identified yielded six viable wash water management strategies, including disposal and reuse. Wash water quality sampling was conducted during winter and winter Results indicated: Many samples met disposal guidelines; however, many samples would not meet reuse limits for heavy metals Particulate metal concentrations were a significant fraction of the total metal concentration for the traffic metals (Cu, Zn, Ni, Cr, Pb, and Fe), indicating the importance of colloidal metal in the samples Binary logistic regression models to assess the probability of exceeding reuse limits were developed for four parameters (total copper, total iron, total zinc, and rural area) 29

30 Conclusions cont. Media filtration pilot testing conducted during winter indicated: The MAR Systems Sorbster media and pilot unit effectively reduced the heavy metal concentration of wash water. A portion of total metal removal by the pilot unit can be attributed to the 5µm filters at the beginning of the pilot unit. Additional tests with 5 µm filters on six different garage wash water samples from garages that exceeded the reuse limits confirmed the importance of physical separation or settling as a removal alternative Particle settling estimates (at a temperature of 40 degrees Fahrenheit) showed an average settling time of 11.7 hours and 15.1 hours for 5 µm size particles of copper and zinc, respectively 30

31 Conclusions cont. Based on the literature review, survey data, and wash water quality results, factors contributing to the cost of each management option were identified. The impact of site specific factors on the cost of each management option were assessed. Results showed: For garages generating higher volumes of wash water, tying into sanitary sewer was the most cost effective option at a capital cost less than $173,640 For garages generating lower volumes of wash water, tying into the sanitary sewer was the most cost effective option at a capital cost less than $95,025 31

32 Recommendations for Implementation Immediate: For all locations that collect and store wash water or reuse, allow at least 24 hours for settling (recall heavy metals concentrations may be adequately reduced through settling) before disposal-reuse and take steps to minimize particulates in the transported-reuse wash water (i.e. avoid mixing and pumping from the bottom of storage tank if possible). Heavy metals concentrations will be reduced. For all locations that pay for commercial disposal, investigate disposal requirements at a WWTP with justification of wash water quality characteristics based on results from this study. Immediate cost savings is likely. Use the cost analysis tool to determine site-specific costs and assess-rank wash water management alternatives for all facilities without access to sanitary sewer. Locations with potential for cost savings will be identified and the potential savings will be quantified. 32

33 Recommendations for Implementation cont. Near-Term (i.e. next year): Use the filtration unit at Meigs County garage in to treat wash water and replace current treatment process. Immediate cost savings via reduced labor is likely, as well as improved water quality of brine made from wash water. Monitor the filtration unit performance and operations at Meigs County garage in This will validate field performance and identify operational issues not covered as part of the research. For locations with high potential cost savings, create a plan-strategy for moving forward with the identified management alternative (see below for guidance-based on quality and modeling results). 33

34 Recommendations for Implementation cont. Long-Term: Continue to monitor the filtration unit performance and operations at Meigs County garage. This will validate long-term field performance of the unit and the use of TDS, turbidity, and iron as surrogates for wash water quality. Discuss the wide-spread potential for reuse with the Ohio EPA and applicable regulations. Periodic analysis of parameters of concern may be required. Future cost savings is likely if implemented and may not require treatment in some instances. 34

35 Snow Removal Wastewater Disposal Alternatives Discussion and Questions? Christopher Miller, Ph.D., P.E. (330) William H. Schneider IV, Ph.D., P.E. (330)

Distillation: Waste Water Treatment for Release to Sewers Jung Bae Eckert & Ziegler Isotope Products, Valencia, California 91355

Distillation: Waste Water Treatment for Release to Sewers - 11067 Jung Bae Eckert & Ziegler Isotope Products, Valencia, California 91355 ABSTRACT Eckert & Ziegler Isotope Products has produced reference/calibration,