Investigating Flammable Waste Trap Solids at MnDOT Truck Stations

By Sara Heger, Jessica Doro and Sondra Larson Water Resources Center at University of Minnesota June 2019

Funding for this project provided by the Minnesota Department of Transportation (MnDOT)

Executive Summary Floor drains at Minnesota Department of Transportation (MnDOT) truck washing facilities capture water, oil, chemicals, and sediment. Flammable waste traps help to separate this waste stream enabling all components to be treated separately using the Minnesota Pollution Control Agency’s Floor Drain Best Management Practices (BMPs) and MnDOT’s Sediment and Flammable Waste Trap Management guidance document. A study was conducted to understand the composition of the solid materials being captured from the sediment traps to identify if the material is a non-hazardous waste. An evaluation was done of the practices involved with disposing of flammable waste trap solids from local MnDOT truck washing and maintenance facilities. Solid samples were collected from these facilities plus nine more local facilities to test for hazardous characteristics. Survey information was collected from ten sites regarding management practices surrounding the flammable waste traps on-site. The flammable waste traps are cleaned once or twice per year. The water leaving the flammable waste trap is either directly connected to a municipal wastewater treatment plant or collected and hauled to one. The oil that floats to the top of the trap is collected and transported off-site. The solid material composed primarily of sand is sent offsite for dewatering and disposal often at a hazardous waste treatment facility or landfill. To supplement the survey, the solids were collected from fifteen flammable waste traps and tested for metals and Volatile Organic Compounds (VOCs). The results for all samples for all contaminants were non-detect. Therefore it can be assumed that the facilities tested are adhering to the Floor Drain BMPs and MnDOT’s Sediment and Flammable Waste Trap Management guidance document and are effective in treating the waste from these facilities. MnDOT may want to do a broader evaluation of this waste stream across Minnesota. If results remain consistent, the sand will not need to be landfilled and could potentially be reused for other purposes.

Introduction There are 150 truck washing and maintenance stations operated by the Minnesota Department of Transportation (MnDOT) in the state of Minnesota, 19 of these are in the metro area (MNDOT Work Zone Safety, 2019). Truck washing and maintenance activities are performed at these stations on equipment including snowplows, pick-up trucks and mowers. Most washing activities are routine with the exception of certain occasions such heavy snow fall events that necessitate more frequent washing.

The most concerning byproducts of truck station maintenance and washing activities are oil and solid wastes like sand and gravel from the roads. If allowed to enter the environment, oil could release toxic chemicals and heavy metals that have the potential to put Minnesota drinking water at risk (MPCA, 2015). Solids like sand and gravel carrying chemicals or other toxic components from the roadways could also enter the environment, and if improperly managed, also effect groundwater and public health (MPCA, 2018).

To mitigate the effect of these waste streams MnDOT is required to use mandated equipment and procedures designed for the treatment of truck washing and maintenance wastes. There are floor drains at each facility designed to catch wash-off water and other materials, directing it into the site’s sediment trap and flammable waste. Oil-absorbing pads can be placed over the drain to catch oil waste before it goes down into the flammable waste trap. Oil-absorbing booms are also used inside the flammable waste trap where they float on top of the liquid to absorb petroleum. When fully saturated, these products are collected and disposed of according to the MnDOT Used Oil Sorbent Management Plan (MnDOT, Used Oil Sorbent Management, 2017).

Flammable waste and sediment traps reduce the amount of oil and solid particulates that move on to the truck station’s holding tank or the municipal wastewater treatment plant. The composites of these tanks include sediment, wastewater and a top layer of petroleum. The sludge is categorized as any material heavier than

water, mostly sand and grit, from the roads. The oil separates out

This photo shows the floor drain for the flammable waste trap at the Arden Hills Truck Station.

This figure shows a cross-section of the type of Flammable Waste or Sediment Trap used at truck stations in MN (MPCA Floor Drains, Separators and Traps, and Holding Tanks, 2017).

and floats at the top of the tank and the water remaining after everything settles is classified as wastewater (MPCA, 2018). Minnesota truck washing facilities must adhere to the state’s standard Floor Drain Best Management Practices (BMPs) for the disposal of these different waste components (Appendix A). If all appropriate BMPs are practiced, the sludge produced in a flammable waste trap can be considered non-hazardous. In this case there are three options for disposal. The sludge can be:

1. Dewatered and disposed of as solid industrial waste, 2. transported off-site to be handled as oil-contaminated waste, or 3. land applied using the MPCA Land Application of Business Floor Drain, Trap and Holding Tank

Wastes guidance document.

Wastewater is classified as non-hazardous as long as BMPs are in place and, after collection, is either routed to the facility’s holding tank or the sanitary sewer (MPCA, 2018).

Reducing the amount of solid material that needs to be landfilled or land-applied could be beneficial to truck station operations. If the sand and grit recovered from flammable waste and sediment traps could be repurposed onsite, it would be more efficient and economical for the truck station. A study was conducted to characterize the solids from the waste stream produced by truck washing and maintenance activities at local Twin Cities MnDOT truck washing facilities. The stations within the parameters of this study have anywhere from seven to thirty-five trucks that are serviced on site and each facility has either one of two flammable waste and/or sediment traps. The objective of this study was to understand MnDOT truck stations waste management processes and identify any hazardous waste components present in the facility’s waste stream from flammable waste traps and sediment tanks.

Methods Survey information was collected from ten truck stations in Anoka, Arden Hills, Buffalo, Dresbach, Forest Lake, Maple Grove, McGregor, North Branch, Plymouth, and Shakopee regarding management practices for flammable waste traps on-site. The site surveys were created by the University of Minnesota Onsite Sewage Treatment Program and administered either by email or by phone. Surveys were given to the site manager at each location to determine how well each facility is following the MPCA’s Flammable Waste Trap BMPs. Dresbach, McGregor and Plymouth surveys were conducted via phone call and the remaining sites were surveyed via email. The survey includes questions to provide details about general site information, the site’s sediment trap and flammable waste traps, adherence to floor drain best management practices, specifics on the site’s waste stream and the frequency and process of cleaning the site’s flammable waste trap. Questions on the survey are grouped into categories for analysis that include: Vehicle Wash Information, Flammable Waste Trap Cleaning Information and Waste Disposal Information. Please see a copy of the full survey in Appendix B.

To construct a full evaluation of the BMP practices at each site, solid waste samples were collected from flammable waste and sediment traps and analyzed for hazardous components. The facilities used in this study were selected because previous work had been done to evaluate the wastewater after the flammable waste trap for potential reuse (University of Minnesota Onsite Sewage Treatment Program, 2019). The sites evaluated in the reuse project were: Anoka, Arden Hills, Buffalo, Dresbach, Forest Lake,

Maple Grove, McGregor, North Branch, Plymouth and Shakopee. The district manager had easy access to some other flammable waste trap waste so samples were obtained from Burls, Lakeville, Maryland, Mendota, Spring Lake Park, Oakdale (old), Oakdale (North) and Oakdale Traffic Service. After the data was obtained from the first 15 sites and all sites were non-detect for all tested parameters the decision was made to discontinue any further analysis at the remaining three sites (Arden Hills, Forest Lake and North Branch) to minimize the amount the project went over budget. Flammable waste trap and sediment trap solids were sampled by staff at the time of a routine clean-out. The method to obtain these samples depended on the trap. The MPCA Land Application of Business Floor Drain, Trap, and Holding Tank Wastes document was used as a guide for sampling and determining which analytes to test for in the samples. Samples were refrigerated and analyzed by Pace Analytical using EPA sampling methods: EPA 6010, EPA 7470A and EPA 8260B for detection of heavy metals and volatile organic compounds (MPCA (2018) Land application of business floor drain, trap, and holding tank wastes).

Results Site Surveys

Survey information was collected from Anoka, Arden Hills, Buffalo, Dresbach, Forest Lake, Maple Grove, McGregor, North Branch, Plymouth, and Shakopee regarding management practices surrounding the flammable waste traps on-site. All sites are used for vehicle wash and maintenance—except for Shakopee, which only performs washes—and the number of vehicles serviced at each site varies, with more frequent washings during winter months (Table 1). Wash bays contain a floor drain with a flammable waste trap used to separate sediment, oil, and wastewater. Flammable waste trap cleanings occur annually or biannually, and methods of waste disposal vary between sites (Table 2). In general, wastewater is sent to municipal facilities for treatment, used oil is collected and transported offsite, and solids are sent offsite for dewatering and disposal (Table 3). MPCA and MnDOT-specific guidelines for flammable waste trap management practices can be found in the Appendix A.

Table 1. Vehicle Wash Information Site Number of

Vehicles Serviced Vehicle Washing Frequency

Floor Sweeping/Cleaning Frequency

Anoka 16 1-2 times per week 1-2 times per month Arden Hills 20 Daily Daily Buffalo 8 -- Weekly, at least Dresbach 8 Daily After every use Forest Lake 20 Weekly Often Maple Grove 33 Weekly Weekly McGregor 7 Weekly Weekly North Branch 15 Often Weekly, at least Plymouth 35 Weekly Weekly Shakopee 30 Weekly Weekly

Table 2. Flammable Waste Trap Cleaning Information

Site Waste Disposal Agreement with

Check Flam Trap for Solids/Oil

Clean Flam Trap Clean Sediment Trap

Anoka Metro Monthly Annually Annually Arden Hills Metro -- -- -- Buffalo In-house crew Biannually Biannually Biannually

Dresbach In-house crew Biannually Annually/Biannually -- Forest Lake Metro Monthly Biannually -- Maple Grove In-house crew -- -- -- McGregor Private company Bimonthly Annually Quarterly North Branch Metro Monthly Annually Annually Plymouth In-house crew Biannually Biannually Annually Shakopee Metro Monthly Annually Biannually

Table 3. Waste Disposal Information

Site Waste Disposal Agreement with

Wastewater Disposal

Oil Disposal Solids Disposal

Anoka Metro City of Anoka municipal facility

Waste oil tank, transported offsite --

Arden Hills Metro St. Paul municipal facility

Waste oil tank, taken by Loes Oil --

Buffalo In-house crew Holding tank, Buffalo municipal facility

Absorbent socks, disposed offsite as hazardous waste

Dewater onsite, MPCA cert. industrial solid waste disposal

Dresbach In-house crew -- Stored onsite, transported offsite for disposal

--

Forest Lake Metro Forest Lake municipal facility

Transported offsite, MPCA used oil guidelines

--

Maple Grove In-house crew Sanitary sewer to municipal facility

Used sorbent container, transported offsite

Vacuumed out, dewatered at Oakdale, sent to landfill

McGregor Private company

Holding tank, private company transports offsite

Absorbent pads, vacuumed out, sent to Duluth vendor

Sent offsite

North Branch Metro -- -- --

Plymouth In-house crew Municipal facility Vacuumed out, transported offsite Sent offsite

Shakopee Metro Holding tank, Blue Lake municipal facility

Stored onsite, taken by Loes Oil Taken by Loes Oil

Waste Stream Analysis

All analytes at all sites were non-detect (ND) in the solid matrix samples tested by Pace Analytical (Table 4). This means the concentrations of each analyte were below detection limits, if present at all, in every sample. This lack of analyte detection can be attributed to adherence to Floor Drain Best Management Practices as outlined by the MPCA. These practices aim to prevent oils, chemicals, and solids from entering floor drains in excess. A comprehensive list of analytes and their detection limits can be found in Table 5.

Surrogate (S) recovery was used for analysis quality control. 1,2-Dichloroethane-d4 (S) recoveries were between 96-101% for all sites; Toluene-d8 (S) recoveries were between 93-99% for all sites; and 4-Bromofluorobenzene (S) recoveries were between 96-103% for all sites.

Table 4. Results of Lab Analysis Site Metals (mg/L) Mercury (µg/L) VOCs (µg/L) Anoka ND ND ND Arden Hills -- -- -- Buffalo ND ND ND Burls ND ND ND Dresbach ND -- ND Forest Lake -- -- -- Lakeville ND ND ND Maple Grove ND ND ND Maryland ND ND ND McGregor ND ND ND Mendota ND ND ND North Branch -- -- -- Plymouth ND ND ND Shakopee ND ND ND Spring Lake Park ND ND ND Oakdale (old) ND ND ND Oakdale (North) ND ND ND Oakdale Traffic Service ND ND ND

ND = non detect “—” = samples not collected

Table 5. List of Analytes Metals VOCs Other

Analyte Detection Limit (mg/L)

Analyte Detection Limit (µg/L)

Analyte Detection Limit

Arsenic 0.50 Benzene 25.00 Mercury 0.60 µg/L Barium 1.00 2-Butanone 125.00 1,2-Dichloroethane-d4 (S) 75-125% Cadmium 0.05 Carbon Tetrachloride 25.00 Toluene-d8 (S) 75-125% Chromium 0.50 Chlorobenzene 25.00 4-Bromofluorobenzene (S) 75-125% Lead 0.50 Chloroform 25.00 Selenium 0.10 1,4-Dichlorobenzene 25.00 Silver 0.10 1,2-Dichloroethane 25.00 1,1-Dichloroethane 25.00 Tetrachloroethane 25.00 Trichloroethane 10.00 Vinyl Chloride 5.00

Recommendations and Future Research Based on the findings from site surveys and the homogeneous result of non-detect from the waste stream analysis at the facilities evaluated, MnDOT is doing a good job managing their flammable waste trap related waste. There were no findings of hazardous materials in the flammable waste trap solids,

therefore it can be assumed that the facilities tested are adhering to the BMPs and are treating the waste from these facilities effectively. If any MnDOT facilities would like to reuse the solid material from sediment and flammable waste traps, testing for the contaminants in this study should be done. This data could then feed into the central office at MnDOT for analysis.

MnDOT may want to do a broader evaluation of this waste stream across Minnesota, involving more truck stations. Additional data could provide more information to guide future disposal options. If results remain consistent, the solid waste from truck station flammable waste traps could potentially be reused onsite for other purposes, resulting in a more efficient and economical operation while protecting Minnesota’s environment. As part of this research, an economic evaluation should be performed to estimate the potential cost savings.

References MnDOT (2017). Sediment and Flammable Waste Trap Management. Office of Environmental Stewardship Environmental Investigation Unit, St. Paul, Minnesota. Accessed 06/11/2019 at: http://www.dot.state.mn.us/environment/regulatedmaterials/pdf/sed-flam-waste-trap-mgmt.pdf

MPCA (2015). Used Oils and Related Wastes. St. Paul, Minnesota. Accessed 06/11/2019 at: https://www.pca.state.mn.us/sites/default/files/w-hw4-30.pdf

MnDOT (2017). Used Oil Sorbent Management. Office of Environmental Stewardship Environmental Investigation Unit, St. Paul, Minnesota. Accessed 06/11/2019 at: http://www.dot.state.mn.us/environment/regulatedmaterials/pdf/used-oil-sorbent.pdf

MnDOT (2019). Work Zone Safety, Snowplow Facts. St. Paul, Minnesota. Accessed 06/11/2019 at: https://www.dot.state.mn.us/workzone/snowplow-facts.html

MPCA (2018). Floor Drains, Separators and Traps, and Holding Tanks. St. Paul, Minnesota. Accessed 06/06/2019 at: https://www.pca.state.mn.us/sites/default/files/w-hw4-18.pdf

MPCA (2018). Land application of business floor drain, trap, and holding tank wastes. St. Paul, Minnesota. Accessed 06/12/2019 at: https://www.pca.state.mn.us/sites/default/files/w-sw4-18.pdf

University of Minnesota Onsite Sewage Treatment Program. (2019) Investigating Wastewater Reuse at MnDOT Truck Stations. University of Minnesota Water Resources Center, St. Paul, Minnesota. http://www.dot.state.mn.us/research/reports/2019/201922.pdf

Appendices

Appendix A: MPCA Floor Drains, Separators and Traps, and Holding

Tanks with Best Management Practices

www.pca.state.mn.us

Minnesota Pollution Control Agency 651-296-6300 | 800-657-3864 or use your preferred relay service | Info.pca@state.mn.us

April 2018 | w-hw4-18 Available in alternative formats

Floor Drains, Separators and Traps, and Holding Tanks Many businesses that store, fuel, repair, or wash vehicles indoors have floor drains to catch snowmelt and wash water from the vehicles. Floor drains may also be used to collect releases from industrial and manufacturing equipment. The wastes held by floor drains and associated plumbing can present risks to human health and the environment if improperly managed. This fact sheet will discuss the waste management requirements for these wastes administered by the Minnesota Pollution Control Agency (MPCA) and the Metropolitan Counties of Anoka, Carver, Dakota, Hennepin, Ramsey, Scott, and Washington (Metro Counties).

What types of waste are generated by floor drains? Floor drains can mix many sources of waste, including wash water, used oil, chemicals, and sediments into a single difficult-to-manage semi-liquid stream. Many floor drain systems include trenches, also known as a sediment trap, and use an oil/water separator, also known as a flammable trap, to segregate these wastes.

Diagram 1: Common parts of floor drain systems

Sludge consists of solids and liquids heavier than water. Sludge may appear to be mainly sand or grit, however it may not be assumed to be clean dirt; it is a solid waste.

Oils consist of the floating liquids that are lighter than water.

Wastewater includes all liquids in your floor drain system after sludges and oils have been removed. Wastewater may appear clear, however it may not be assumed to be clean water; it is a regulated wastewater.

How must floor drain wastes be managed? Sludge If you have documented that your site follows the Floor Drain Best Management Practices (BMPs) on page 4, you may assume that your sludge is non-hazardous. You may manage non-hazardous sludge by:

· Dewatering it into your floor drain system and then disposing of the solids as an industrial solid waste. Do not dewater sludge on the ground. Do not use sludge as fill on your site or spread it on the ground. If managing it as a solid waste, place it into your solid waste collection container.

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· Sending it off-site as a used oil-contaminated waste. You may mix sludge with other solid used oil-contaminated wastes, such as used floor dry and sorbents. See MPCA fact sheet #w-hw4-30, Used Oil and Related Wastes, at https://www.pca.state.mn.us/sites/default/files/w-hw4-30.pdf.

· Land applying it at your site or another site. You must follow the requirements in MPCA fact sheet #w-sw4-18, Land Application of Business Traps and Holding Tanks, at https://www.pca.state.mn.us/sites/default/files/w-sw4-18.pdf.

If your site has not followed the Floor Drain Best Management Practices on page 4, you must assume that your sludge is a hazardous waste. See MPCA fact sheet #w-hw1-06, Treat or Dispose of Hazardous Waste, at https://www.pca.state.mn.us/sites/default/files/w-hw1-06.pdf to determine how to manage it.

Oils You may manage floating oils as used oil. See MPCA fact sheet #w-hw4-30, Used Oil and Related Wastes, at https://www.pca.state.mn.us/sites/default/files/w-hw4-30.pdf.

If you do not manage the floating oils as used oil, you must evaluate them to determine if they are a hazardous waste. See MPCA fact sheet #w-hw1-01, Evaluate Waste, at https://www.pca.state.mn.us/sites/default/files/w-hw1-01.pdf.

Wastewater If you follow the Floor Drain Best Management Practices on page 4, you may assume that your wastewater is non-hazardous. You may manage non-hazardous wastewater by:

· Discharging it through a sanitary sewer to a municipal sewage treatment plant, also known as a publicly owned treatment works (POTW). Notify the receiving POTW and comply with any reporting or testing conditions they require.

· Accumulating it in an on-site holding tank before transporting it via truck to a POTW that has agreed to accept the wastewater.

· Land applying it at your site or another site. You must follow the requirements in MPCA fact sheet #w-sw4-18, Land Application of Trap and Holding Tank Wastes, at https://www.pca.state.mn.us/sites/default/files/w-hw4-30.pdf, unless the wastewater is from a vehicle wash or storage site. *If your wastewater is only from a vehicle wash or a vehicle storage site where no vehicle maintenance, including oil changes, is performed, you may instead follow the less stringent requirements in MPCA fact sheet #w-lndapp2-08, Land Application of Vehicle Wash and Vehicle Storage Wastewater, at https://www.pca.state.mn.us/sites/default/files/w-lndapp2-08.pdf.

If your site has not followed the Floor Drain Best Management Practices on page 4, you must assume that your wastewater is a hazardous waste. See MPCA fact sheet #w-hw1-06, Treat or Dispose of Hazardous Waste, at https://www.pca.state.mn.us/sites/default/files/w-hw1-06.pdf to determine how to manage it.

How may floor drain wastes not be managed? 'Daylighted' open drain The practice of discharging floor drains directly to the ground outside a building, commonly known as 'daylighting', is prohibited in Minnesota for commercial sites and for residential garages used for commercial activities, such as home-based auto repair businesses.

Septic system Septic systems that receive any commercial or industrial wastes beyond sink, toilet, and cooking wastes are considered Class V injection wells that are closely regulated by the U.S. Environmental Protection Agency (EPA). They are also discharges to the unsaturated zone regulated by the MPCA. Septic systems are also known as subsurface treatment systems (SSTS) or individual sewage treatment systems (ISTS).

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EPA Class V injection well regulation Most Class V injection wells that receive wastewater from floor drains where any motor vehicle servicing or repair is performed, including home-based auto repair businesses, are prohibited, even if the BMPs in this fact sheet have been followed.

Some Class V injection wells that receive wastewater from floor drains where any motor vehicle servicing or repair is performed, but that have been in operation since before 2000 and are not in a wellhead protection area, are allowed, but only if their operators submit well inventories to the EPA, test their discharges, and document that their discharges meet drinking water standards. These standards are extremely difficult for most floor drain wastewater to meet.

Other Class V injection wells that receive any other commercial wastes, including from floor drains at factories, coating operations, and warehouses, are allowed only if their operators submit well inventories to the EPA, test their discharges, and document that their discharges meet drinking water standards. These standards are extremely difficult for most floor drain wastewater to meet.

For more information regarding Class V injection well requirements, visit the EPA at http://www.epa.gov.

MPCA regulation The MPCA regulates all discharges of business wastes to the ground, other than sink, toilet, and cooking wastes, as discharges of potential pollutants to the unsaturated zone. Discharge of any potential pollutant to a septic system is prohibited if it does not meet drinking water standards. These standards are extremely difficult for most floor drain wastewater to meet.

More information Guidance and requirements in this fact sheet were compiled from Minnesota Rules, Chapters 7035, 7045, 7050, 7060, and 7080 and incorporate regulatory interpretation decisions made by the MPCA in December 1993, and on March 23, 2018. Visit the Office of the Revisor of Statutes at https://www.revisor.mn.gov/pubs to review applicable Minnesota Statutes and Rules.

For more information, contact your Metro County hazardous waste office or the MPCA. The MPCA's Small Business Environmental Assistance Program can provide free, confidential compliance assistance for many businesses. The Minnesota Technical Assistance Program can assist you with waste minimization and pollution prevention. Report all spills of hazardous waste or other pollutants immediately to the Minnesota Duty Officer.

Metro County Hazardous Waste Offices Anoka .................................. 763-324-4260 ..................... https://www.anokacounty.us/ Carver .................................. 952-361-1800 ......................http://www.co.carver.mn.us/ Dakota ................................. 952-891-7557 ....................https://www.co.dakota.mn.us/ Hennepin .............................. 612-348-3777 ........................... http://www.hennepin.us/ Ramsey ................................ 651-266-1199 ................... https://www.ramseycounty.us/ Scott .................................... 952-496-8177 ................. http://www.scottcountymn.gov/ Washington .......................... 651-430-6655 ............. https://www.co.washington.mn.us/

Minnesota Pollution Control Agency Toll free (all offices) ..................... 1-800-657-3864 All offices ......................................651-296-6300 ............................. https://www.pca.state.mn.us/

Minnesota Duty Officer Toll free ..................................... 1-800-422-0798 Metro ...........................................651-649-5451

Small Business Environmental Assistance Program Toll free ..................................... 1-800-657-3938 Metro ...........................................651-282-6143 ................... https://www.pca.state.mn.us/sbeap/

Minnesota Technical Assistance Program Toll free ..................................... 1-800-247-0015 Metro ...........................................612-624-1300 ............................... http://www.mntap.umn.edu

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Floor Drain Best Management Practices If you… Then…

Are connected to a city sanitary sewer (POTW)

Notify the city's sewage treatment plant (POTW) operator about your floor drain wastes. Comply with any conditions required by the POTW.

Have a septic system at your site Collect all floor drain waste in a holding tank. Ensure that no floor drain waste is discharged to the septic system or a 'daylighted' open drain.

Use aerosol-dispensed solvents or degreasers

Clean parts over a drip pan, not the floor. Transfer the drip-off from the pan immediately after use to a closed waste container. Manage the waste container as instructed in MPCA fact sheet #w-hw1-05, Accumulate Hazardous Waste, at https://www.pca.state.mn.us/sites/default/files/w-hw1-05.pdf. You may also consider cleaning parts in a parts washer instead of using aerosol-dispensed solvents and degreasers whenever possible.

Change vehicle fluids (motor oil, brake fluid, etc)

Use drip pans under vehicles to collect fluids. Manage motor oil, brake fluid, and transmission fluid as used oil as instructed in MPCA fact sheet #w-hw4-30, Used Oil and Related Wastes, at https://www.pca.state.mn.us/sites/default/files/w-hw4-30.pdf.

Clean shop floors Use dry sweeping compounds if needed instead of hosing floors down. Manage used sweeping compounds and other absorbents contaminated with fuels or used oil, such as floor dry, as used oil-related wastes as instructed in MPCA fact sheet #w-hw4-30, Used Oil and Related Wastes, at https://www.pca.state.mn.us/sites/default/files/w-hw4-30.pdf.

Spill products or wastes Clean up all spills immediately, even small ones. Maintain appropriate spill control equipment and perform required emergency planning for your hazardous waste generator size. See MPCA emergency planning fact sheets for: ü Very Small Quantity Generators #w-hw1-08a https://www.pca.state.mn.us/sites/default/files/w-hw1-08a.pdf ü Small Quantity Generators #w-hw1-08b https://www.pca.state.mn.us/sites/default/files/w-hw1-08b.pdf ü Large Quantity Generators #w-hw1-08c https://www.pca.state.mn.us/sites/default/files/w-hw1-08c.pdf If you are unsure of your hazardous waste generator size, see MPCA fact sheet #w-hw1-02, Determine Generator Size, at https://www.pca.state.mn.us/sites/default/files/w-hw1-02.pdf.

Store liquid chemicals, fuels, or oils

Keep containers closed. Ensure all product containers are labeled with their contents. Store flammable chemicals in a fire-resistant cabinet with integral containment.

Store liquid wastes Keep containers closed. Ensure that no possible leaks could reach your floor drain. Inspect waste containers weekly. Follow all other waste accumulation requirements in MPCA fact sheet #w-hw1-05, Accumulate Hazardous Waste, at https://www.pca.state.mn.us/sites/default/files/w-hw1-05.pdf

Wash vehicles Post signs prohibiting engine washing by employees and customers. Immediately stop any employee or customer washing engines.

Appendix B: Flammable Waste Trap Study Survey

Flammable Waste Trap Study Survey

Site Information

1. Site name:

2. Is this site for washing vehicles only, or for vehicle wash and maintenance?

3. How many vehicles are washed or serviced on this site?

4. How often are vehicles washed in the area where the floor drain is located?

5. Approximately how much water is flowing into the floor drain and flammable waste trap? (How

much water is used to wash vehicles)

6. How often is the floor swept or cleaned in the area around the floor drain?

7. Does this site have agreements with the metro or a private company to dispose of waste from

the flammable waste trap?

8. What materials are stored in the room/area where the floor drain and flammable waste trap are

located?

a. Are there any hazardous materials stored here?

Interceptor Information

1. Is the interceptor rated, unrated, or specially engineered for this site?

a. If rated, what is the rating?

2. What was the installation date of the flammable waste trap? (How long has this interceptor

been in use?)

3. What are the dimensions of the flammable waste trap?

4. What is the flow capacity of the flammable waste trap?

a. Total:

b. Liquid:

c. Sand/solids:

5. What is the discharge rate out of the flammable waste trap?

6. Is there an overflow line to a waste oil tank?

a. Is this line gravity flow or pumped?

7. What is the holding capacity of the overflow storage tank (if one is present)?

a. How much waste is ever stored or accumulated in this tank?

8. How often is the flammable waste trap checked for solids and oil accumulation?

9. How often is the flammable waste trap cleaned?

10. How often is the sediment trap cleaned or replaced?

11. How closely are current floor drain best management practices being followed? (Chapter 10,

Section 1017 of 2015 Minnesota Plumbing Code)

Waste Stream Information

1. When was the waste stream last tested?

a. Was there any hazardous waste present?

b. Were the oil, sludge/solid, and liquid phases tested separately or as a slurry?

2. Have any changes in management practices, waste generation or loading to the floor drain and

flammable waste trap occurred since the waste stream was last tested?

3. Is the wastewater directed to a holding tank or to a municipal wastewater treatment facility?

4. How often is the holding tank cleaned out?

5. When the holding tank is cleaned, is the liquid phase put back in the tank or taken offsite?

6. Is the wastewater ever land applied?

a. Is the land applied waste just the liquid phase, or a mixture of liquids and solids?

b. Who performs the land application?

c. Where is the waste land applied?

d. When or how frequently is waste land applied?

e. How much waste is discharged with any given land application?

7. If wastewater is directed to a municipal wastewater treatment facility, which facility receives the

waste?

a. Is the waste received as it is generated, or in metered doses?

8. How are oils disposed of?

a. Managed as used oil according to MPCA guidelines? (MPCA 2015 factsheet: Used Oil

and Related Wastes)

i. Stored onsite

ii. Reused

iii. Burned

iv. Transported offsite

b. Other (please describe)

9. How are solids disposed of?

a. Dewatering of sludge onsite and disposing of solids as industrial solid waste

b. Sent offsite as used oil contaminated waste

c. Land applied

d. Other (please describe)

10. What is the quantity of waste generated—oils, solids, and water—between each cleaning of the

flammable waste trap? (How much waste is being handled with each cleaning)

11. Report any incidence of spills since the last flammable waste trap cleaning

a. What was spilled?

b. When did the spill occur?

c. Approximately how much was spilled? (How much entered the floor drain)