Troubleshooting

Special Problems:

Applying the Scientific Process

ODORS

Inside

Venting

Outside

Seals

Filters

Tank Start-up [New Systems]

Toxic tank

Cleaning Chemicals

Construction Chemicals

Other Outcomes

First time on septic- Education on use

Understanding the need for maintenance

Toxic Waste

Corrosion in the Tank

Hydrogen Sulfide

Lack of Venting

Maintenance

Corroded Tanks

What causes corrosion

When does the tank get replaced

Water Softener

Salt- Concrete

Scum- Separation

Additional water

Freezing

Drip

Use

Venting

Drainage

Traffic

Parking

RV

Snowmobiles

Extra traffic

Pets

Extra Water

USE

EXTRAS

OTHER SOURCES

Extras

Garbage disposal

Higher organic loading

Higher hydraulic loading

Slower to breakdown

Slower to settle

Jacuzzi or the like

Additions onto the houseor other add-ons

Mixing in the Tank

Solutions

Capacity

Eff. Screen

Loading

Timer control

Problems

Peak use

Energy inputs

Pumping to tank

Elevation

difference

Upstairs use

Temperature

Other water sources “Clean”

Drains

Sump pumps

Roof leaders

Additional water

Drainage

Surface

In the house

Lawn

watering

Blockage

Family cat

Building sewer

Settling

Septic tank

Distribution box, drop box

Frozen pipes

Animals getting into the system

Roots

Symptom of problem

Replace leaky component

Soil treatment area?

High Strength

What is IT? BOD5

Biochemical oxygen demand

5 days

> 175 mg/L

Organic

Amount of oxygen

used by bacteria

CBOD is different

TSS

Total suspended solids

> 60 mg/L

Inorganic

Paper- Dirt

FOG

Fats, oil and grease > 20 mg/L

Fats Animal

Solid

Oils Veg.

Liquid

Grease Tougher

Restaurant Waste Strength - MN 20 restaurants

Sample 4 times

BOD

TSS

FOG

Restaurant Result

FOG

mg/L

TSS

mg/L

BOD5

mg/L

# of

Restaurants

Type of

Restaurant

1321848743Bar

20014210104Golf Club

21921311305Service

28220212868Fast Food

How do you figure it out?

Use

Maintenance

Testing

Sampling

Average-

Mixed location

18 hours of peak

Worst case

BOD/TSS

Plastic

FOG

Glass

How does it impact the

system?BOD

Typical amount

Biomat development

Recoverable

Fix

Use

Maintenance

PretreatmentClogged Media Filter

TSS

Typical amount

Physical plugging

Fixable?

Avoid

Effluent Screen

Maintenance

FOG

Typical amount

What happens?

Use

Degreasers

Temperature

Pretreatment

Questions?

Alternative Onsite Wastewater

Treatment Systems

What are the choices?

Conventional Septic System

Septic

Tank

House Tank Soil Treatment

Why use alternative systems?

New idea

Sizing

Additional treatment

Separation

Soil Problems

Natural

Clay

Caliche

Fill

Keys

Records

Proper application

Management

Increased cost

Increased maintenance

Conventional systems have proven themselves

Concerns What are the choices? Aerobic treatment units

Media Filter Sand

Peat

Etc

Re-circulating Filters

Textile Filters

Constructed Wetland

Drip Distribution

Separation technologies

Others

Aerobic Tank

Alternative System

SepticAdvanced

Treatment

HouseAdvanced

Treatment

Septic

TankSTA

Aerobic Treatment Unit ~ ‘ATU’

Purdue University

Aerobic Treatment Unit

How does it work? DO, microorganisms and food must be in contact

The effluent is aerated via one of several means.

Aerobic organisms digest food

Generates high quality effluents with variety of oxidized end products - little odor, stable effluent not requiring further breakdown

10 - 20 times faster than anaerobic

Aerobic Treatment Unit

Aerobic Treatment Unit

Suspended growth

Aerobic Treatment Unit

Sequencing batch reactors or Periodic

processes

USEPA Manual, 2002USEPA Manual, 1980

Intermittent inflow Continuous inflow

Aerobic Treatment Unit Attached growth

Packed bed media

Attached growth media

Aerobic Treatment Unit

Rotating biological contactor

RBC

Media Filters Media Filter What is it?

A container or

lined excavation

containing a

specific media

through which

wastewater flows

Single pass

Re-circulating

Unsaturated flow

An aerobic, fixed-

film bioreactor

Media Choices

Washed, graded sand

Gravel

Bottom ash from coal-fired plants

Peat

Synthetic textile materials

Foam chips and cubes

Crushed glass

Wetlands

Other

Media Filter Single-pass option

Media Filter Peat

NSFC

Media Filter

Other

Nibbler

Flow Path in RMF Media Filter

Foam cubes

Textile Filter Sheet Media Filter

Expected treatment efficiencies

Single-pass

BOD5 - <10mg/l

TSS - <10mg/l

Fecal coliform - 99 - 99.99% reduction

Multiple-pass

BOD5 - <10mg/l

TSS - <10 mg/l

Fecal coliform - 99 – 99.9 % reduction

Advanced Treatment Options

Constructed wetlands – subsurface flow

Constructed Wetland

Effluent flows horizontally past roots of plants

Aquatic plants filter nutrients and pathogens

Anaerobic and aerobic organisms help

NSFC

Advanced Treatment Options

Disinfection

Disinfection What is it?

A process of destroying pathogens in the wastewater stream by killing them or preventing their replication

Disinfection can be accomplished by : Chemical agents

Physical agents

Irradiation

For small flows chlorination and ultraviolet light are usually used

Disinfection

Chlorination

Most widely

used

disinfectant

For individual

systems,

calcium

hypochlorite is

usually used.

Disinfection Ultraviolet radiation

Currently, for small wastewater flows most

UV units have bulb vertically oriented.

Separation Technology

i.e. “separate” kinds of wastewater

Dual systems:

Toilet - composting, incinerating, low-flow

to holding tank (black water)

All other water:

Downsized typical tank/soil treatment

Downsized tank/pre-treatment/soil treatment

Reuse

Composting Toilet

Recycling System

Drip Dispersal

Adding water to a large area

Adding water slowly

Adding water shallowly

Drip System Key Points

Questions?