PMSA Conference 1/20/14

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Clara Newton
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Defined: Used water and water-carried solids Sara Heger sheger@umn.

edu Domestic/Residential Commercial Industrial Strength Usually greater than residential Operation based Food

Child care centers Inn/Lodge/B&B Visitor Center/Concessions Water usage relates to business Meals served Cash flow Key

Digested and undigested animal and vegetable material Synthetic (artificial) organic compounds Laundering and bathing

1 Defined: Used water and water-carried solids Sara Heger Domestic/Residential Commercial Industrial Strength Usually greater than residential Operation based Food preparation Restrooms Laundry Restaurants, Bars Churches Schools Campgrounds Supermarkets Convenience Store/Mini Mart Child care centers Inn/Lodge/B&B Visitor Center/Concessions Water usage relates to business Meals served Cash flow Key to problem identification Must measure actual water used Never assume relationship of actual vs design flow. What? Digested and undigested animal and vegetable material Synthetic (artificial) organic compounds Laundering and bathing Impacts? Requires oxygen to be broken down Biochemical Oxygen Demand (BOD) Lowers water quality in lakes, rivers, and streams How treated? Removed and stored in septic tank Effluent screen helps reduce further Serves as food source for good soil bacteria in soil treatment system

Waste from plant or animal sources Can be dissolved, a solid or a liquid Broken down and consumed by microbes (aerobes and anaerobes) As it decays, dissolved oxygen is depleted Everything Soda

moisturizing cream, tanning oils A degreaser (emulsifier) will move all FOG components through a system Origin: Animal fats Examples: lard, solid state, meat fat, butter State: solid at room

2 Waste from plant or animal sources Can be dissolved, a solid or a liquid Broken down and consumed by microbes (aerobes and anaerobes) As it decays, dissolved oxygen is depleted Everything Soda fountains Soft serve ice cream Alcohols Food waste Greasy foods Degradable Animal or vegetable-based FOG Residential kitchens Non-degradable Petroleum-based FOG Industry/automotive repair Bath oils, moisturizing cream, tanning oils A degreaser (emulsifier) will move all FOG components through a system Origin: Animal fats Examples: lard, solid state, meat fat, butter State: solid at room temperature Treatment: separate into scum, microbial degradation, non-toxic Requires 4 times more energy than BOD to break down Origin: Vegetable or plant State: liquid or solid at room temperature Treatment: separate into scum, microbial degradation, nontoxic Requires 12 times more energy than BOD to break down Origin: Petroleum product Example: Sun tan lotion, petroleum jelly, body oils. State: solid or liquid at room temperature Treatment: separate into scum, toxic to microbial activity

3 0 0 0 PMSA Conference 1/20/14 What? Minerals, metals and salts from soil material, plumbing, make-up Impacts? Inert and not subject to decay Causes clouding of water (turbidity) Plugging of soil pores How treated? Stored in septic tank and removed when septic tank is pumped Effluent screen helps reduce further Type of Restaurant Fast Food Service Golf Club Bar Restaurants Sampled, # University of Minnesota, Water Resources Center BOD 5 mg/l TSS mg/l FOG mg/l restaurants located in Texas Sampled during June, July, and August samples per restaurant and 336 total observations Most conclusive study to date N= 284 Removed 11 values between 4,100 and 20,100 mg/l 9 values TSS/FO G Relative Frequency 20% 18% 16% 14% 12% 10% 8% 6% 4% 2% 0% Concentration (mg/l) data gamma Gamma Value Lesikar et. al (2006) 15 N = 312 Removed 4 values between 15,100 and 91,800 mg/l 16 values BOD 5 /FO G Relative Frequency 30% 25% 20% 15% 10% 5% 0% Concentration (mg/l) Lesikar et. al (2006) data gamma Gamma Value N = 311 Removed 13 values between 1,129 and 700,000 mg/l 7 values BOD 5 /TSS Relative Frequency 35% 30% 25% 20% 15% 10% 5% 0% Lesikar et. al (2006) Concentration (mg/l) data gamma Gamma Value

4 0 5 PMSA Conference 1/20/14 N = 335 Remove 25% d 1 value 20% 15% of 97 10% gallons/ 5% seat-day 0% Relative Frequency data gamma Gamma Value Parameter Value (mg/l) % Data Covered BOD TSS Flow (gal/day-seat) FOG Lesikar et. al (2006) Person completing the survey / Reference Number Client Contact Information Facility Operational Data Water Use Habits Onsite Wastewater Treatment System Table 7.2 Characteristics (average range of values) of restaurant wastewater* Parameter Chinese Restaurant Western Restaurant American Fast food Student Canteen Bistro BOD 5 (mg/l) TSS (mg/l) FOG (mg/l) Chen et.al Possible Indicator Final Parameter Estimate Cuisine Type -- Primarily Mexican Primarily Asian Seafood Single Service- primarily American Full Service primarily American Self Serve Salad Bar Number of Seats Note: Seafood was arbitrarily set as baseline for the Cuisine type category Data Source: Garza, 2005 M.S. Thesis Texas A&M University

treatment components How many hours in the

5 Hours of operation have a significant impact on: Hydraulic Loading Necessary treatment components How many hours in the day? How many days a week? When do peak flows occur? Per Meal Breakfast Lunch Dinner Per Day Seasonally Special Events Seasonal Capacity Number of seats Larger - generall y means greater flows Total Per Shift Shifts/day Are they safe? Is it effective? Claims regarding treatment Where is the waste material in the system? Read the label Private Well Centralized System Other Water characteristics

6 Adds to blackwater volume Restaurant location Town Remote area - Everyone stops Is the facility located off a freeway exit? More likely to be used as a public bathroom Excess blackwater flow Total Indoor Patio all weather Kid s Play Area Meals served through drive-up window Daily Weekly Seasonally Decrease bathroom usage Blackwater vs. Greywater Increased FOG Increased BOD and FOG

7 Impact ph Soda products -acidic More soda in the wastewater stream Sugars Excess during serving goes down the drain Milk products in the OWTS Lowers ph Elevated FOG Removal in system Fat and oil management Recycling fats and oils Fat Lard Oil Liquid Shortening Why do restaurants use preservatives? Impact microbial processes in treatment system Does the facility use preservatives? Does the facility have one? Increases undigested food

Water runs the whole day Lower BOD conc.

8 Temperature can effect the state of the FOG Chemicals can also emulsify FOG Dishes should be scraped of extra food before washing Disposable or Washable Draining and refilling frequency can produce large wastewater surges Lower temperature Are frozen foods defrosted under running water? Water runs the whole day Lower BOD conc. Increase water volume Wastewater flow relatively consistent Drain cleaners used Drain strainers used Collect solids Limit ability to send solids down drain Safety mechanism No cooking oils or fats Chemicals Used Routine cleaning Periodic cleaning Waxed floors Cleaning water disposal Wash-does water goes down the floor drain Other disposal method Floor drains - facility management issue

Does the facility have a laundry machine to

used Never assume relationship of actual vs

Water pressure can influence the flow Water

pressure can yield a greater flow Faucet

Reverse osmosis Backwashing water filter

Treated water quality characteristics Air

9 Does the facility have a laundry machine to wash floor mats, table cloths, and other items? Flow BOD Water usage relates to business Meals served Cash flow Key to problem identification Must measure actual water used Never assume relationship of actual vs design flow. Water pressure can influence the flow Water fixtures are an orifice for flow Greater pressure can yield a greater flow Faucet Toilet Water softener recharge water Reverse osmosis Backwashing water filter Other water treatment device clean water Treated water quality characteristics Air conditioning drains Commercial Ice machines Footing drains Sump pumps Groundwater infiltration Is the a grease trap in the kitchen or outside? Must be cleaned out on a regular basis. Dilute strength Add extra flow Can raise DO

Is the flow from the bathroom and the kitchen commingled?

indication of trends Where in the treatment train is the sample collected?

characteristics asked about can be modified/managed.

10 Is the flow from the bathroom and the kitchen commingled? Combined inside or outside the facility Gray and black water separation Collecting monthly flow readings over the course of an entire year can give some indication of trends Where in the treatment train is the sample collected? There are individual checklists that ask questions to collect information that can be helpful in characterizing the waste stream of the system Many operational characteristics asked about can be modified/managed. Failure may be due to high organic loading Management considerations Blackwater and graywater separation Wastewater source separation Holding tanks Working with the owner May be economically beneficial to treat a waste stream separately or pump and haul it away. Streams with very high chemical use that will negatively affect the treatment system. Floor drains, utility sinks, laboratory drains, disinfecting basins and dishwashers Streams that require a long detention time

11 Diversity of Flows from a Supermarket Can wastewater treatment system tolerate the chemical Hauled for offsite disposal Must be pumped on a frequent basis Sometimes a temporary fix Designed based on the capacity of the pump truck and their dumping requirements Lower the extreme surge Special events Too costly for infrastructure needed for special event extreme flow/strength If the surge flows only happen a few times a year Pump the extra flow from surge - equalization tank Decrease flow Facility with hydraulic issues Too costly for infrastructure needed for special event Meet a special need Special events Strip Mall Multiple stores Different sources Initial tank for each facility Rental contract tied to wastewater quality & quantity

Configuration of the system and the facility operation can be changed to influence treatment Start-up phase - monitor closely in first months of operation System is subject to the source Educate

Separate waste streams Grease interceptor or trap Temperature moderation Collects fats, oils, and grease Baffles extend lower into tank than septic tank Temperature is a key factor Design Minimum of

12 Configuration of the system and the facility operation can be changed to influence treatment Start-up phase - monitor closely in first months of operation System is subject to the source Educate users on proper procedures and how their usage is impacting the system Best - Minimize their source Use evaluation surveys Find operations that can be changed or eliminated salad bar? Separate waste streams Grease interceptor or trap Temperature moderation Collects fats, oils, and grease Baffles extend lower into tank than septic tank Temperature is a key factor Design Minimum of 24 hours (1 day) of hydraulic retention time is recommended, but can be up 4 days or more Estimate 70% of total design flow if actual kitchen flows are unavailable Outlet baffle should extended to 50-70% of liquid depth Needs frequent pumping Evaluated quarterly at a minimum to determine if cleaning/pumping is needed Cold climates can require increased temperatures Insulation of components Adding heat to component - warm air Aeration systems may need warmed air

Remember EVERY FACILITY IS UNIQUE; what works for one may not work for another

Heavily influenced by facility management Evaluate whether the facility is

Recovery features need to be incorporated into the design of commercial systems

components Eliminate the need for guessing by adding a means to collect accurate

13 Remember EVERY FACILITY IS UNIQUE; what works for one may not work for another What is a comparable facility? Heavily influenced by facility management Evaluate whether the facility is operating at assumed design values. Recovery features need to be incorporated into the design of commercial systems that will treat HSW Pretreatment components Final treatment and dispersal components Eliminate the need for guessing by adding a means to collect accurate and vital flow data for troubleshooting Recirculation of semi-treated effluent to dilute high strength wastewater Denitrification Example- Media filters Meter Cycle counter Elapsed time meter

Technology designed for commercial strength waste Sufficient septic tanks prior to unit 3-4 days of design hydraulic retention time Air is approximately 19% oxygen.

Balance efficiency of oxygen transfer and volume of air moved through the unit.

prevent the passage of solid particle larger than a nominal 1/8 inch diameter sphere. Must be frequently cleaned.

14 Technology designed for commercial strength waste Sufficient septic tanks prior to unit 3-4 days of design hydraulic retention time Air is approximately 19% oxygen. Oxygen in the air bubbles must transfer to water. Oxygen molecules diffuse through the air in the bubble and then across the bubble surface and into the water. Balance efficiency of oxygen transfer and volume of air moved through the unit. Type of Oxygen Transfer in ATUs Liquid system - Saturated Dissolved Oxygen O2 O2 Less Transfer More Transfer Oxygen Transfer Additional removal of solids Should prevent the passage of solid particle larger than a nominal 1/8 inch diameter sphere. Must be frequently cleaned. Frequent clogging of the effluent filter may indicate need for changes in the facility Sometimes when repairing, it is most economical to abandon the existing system and start over with a new system Owner education is vital Most effective to demonstrate the economical benefits. Management relates directly to waste stream

15 Fix leaking plumbing fixtures Lower water pressure Use automatic shut-off faucets Use water-saver dishwasher cycle Scrape plates into garbage, not the sink Install drain covers and sink baskets/strainers. Avoid use of a garbage disposal Avoid using slop sinks to dispose of liquid food items. Kitchen layout for dish washing. Dish storage? Insufficient storage peak usage leads to quick placement into dishwasher and with no scraping Avoid use of harsh detergents: hand washing & automatic Hand washing disinfection process Isolate harsh flows

INSPECTING AND EVALUATING SOIL TREATMENT SYSTEMS & REMEDIATION SARA HEGER UNIVERSITY OF MINNESOTA

INSPECTING AND EVALUATING SOIL TREATMENT SYSTEMS & REMEDIATION SARA HEGER UNIVERSITY OF MINNESOTA SHEGER@UMN.EDU WWW.SEPTIC.UMN.EDU PRESENTATION OVERVIEW Evaluating soil treatment system Excessive ponding