A presentation about innovative onsite wastewater treatment systems to remove nitrogen. Presented by Brian Baumgaertel, Environmental Project Assistant for the Barnstable County, Massachusetts, Department of Health and Environment, during the Buzzards Bay Coalition's 2013 Decision Makers Workshop series. Learn more at www.savebuzzardsbay.org/DecisionMakers
Measures of Central Tendency: Mean, Median and Mode
Innovations in Onsite Wastewater Treatment
1. Brian Baumgaertel
Environmental Project Assistant
Barnstable County
Department of Health and Environment
2. Agenda
What are Innovative/Alternative (I/A) wastewater
treatment systems?
What we do at BCDHE.
Real-World I/A System
Performance.
What’s On the Horizon
for I/A technology?
Disclaimer: The presence of a product or service in the presentation is in no way
construed as an endorsement, advertisement or otherwise of that product or service.
3. What is an I/A System?
Add-on or replacement for
standard onsite septic
components for enhanced
wastewater treatment.
Typically includes mechanical
components such as pumps,
filters and bacterial growth
media.
In southeastern Massachusetts,
typically installed to reduce
nitrogen.
A typical septic system.
4. Advanced treatment units manipulate the
nitrogen cycle to return fixed nitrogen to the
atmosphere
Nitrogen returns to Nitrogen from the atmosphere
atmosphere is fixed into tissue by plants
Oxygen deprived
bacteria convert nitrate We or animals eat the
to nitrogen gas. plants
Leachfield bacteria We digest the food and
convert ammonium to eliminate excess nitrogen
nitrate (70% as urea)
Septic tank bacteria convert urea
to ammonium
5. Diagram of a Septic System
“Standard” Septic System I/A Septic System
Incoming Incoming
Wastewater Wastewater
Septic Tank Septic Tank
Recirculation
“Black Box”
Leach Field Leach Field Alternative
Drainfield
6. What the Barnstable County Department of Health and
Environment is doing in the world of onsite technology.
7. MASSTC – The Massachusetts
Septic System Test Center
Began in 2000 for the purpose of testing new and
innovative onsite technologies.
9. I/A Monitoring and Compliance
In 2005, BCDHE created a web-based database to
collect maintenance and sample reports for I/A
systems for 14 towns in Barnstable County.
Provide the initial level of compliance on behalf of
town Boards of Health.
Analyze incoming data and provide reports to the
public to help determine efficacy of various
technologies and I/A in general.
10. The Benefit of Close Monitoring
System maintenance is taken more seriously when
homeowners and operators know someone is
watching.
We have seen a roughly 10% improvement in system
performance (i.e. lower effluent nitrogen) since county
program began.
11. Using real-world data to help clarify the question of the efficacy
of I/A technologies in wastewater planning.
12. What is meant by “Performance”?
The ability of an I/A system to
remove a particular contaminant.
Nitrogen
19 mg/l residential
25 mg/l commercial
13. Why 19mg/l for Nitrogen?
Assumptions:
• 2.9kg nitrogen per person per year
• 55 gallons water use per person per day
System Influent Concentration:
~38 mg/l Total Nitrogen
50 Percent Removal:
19 mg/l Total Nitrogen
17. Box-Whisker Diagrams
Min/Max Value Min/Max Value
Box
Median – Middle Value
Whiskers
50%
25% 25%
Probability Density Graph (“Bell Curve”)
18. Box-Whisker Diagram Examples
60
A – A “Good” System. Box
and whiskers are short and
50
compact.
B – A “Bad” System. Results
are all over the place. Box 40
and whiskers are stretched
out.
30
C – A “Consistently Bad”
System. Compact but well
above TN limit (19 mg/l) 20
D – A “Usually Pretty
Good” System. Compact 10
but maybe a couple of high
results.
0
A B C D
24. To Sum it Up
Nitrogen
Total Meeting Percent Meeting
Building Use Removal Count
Standard Standard
Standard
Single Family 19 mg/l 549 432 78%
Multi-Family 19 mg/l 79 56 71%
Commercial 25 mg/l 53 40 75%
Total 681 528 77%
25. Currently installed I/A technologies
remove about 50 percent of incoming
nitrogen about 75 percent of the time*.
*Assuming our set standards (i.e. 19mg/l) are representative of 50% removal!
26. Is 19mg/l Really 50% Removal?
Is 2.9 kg nitrogen/person/year
a valid assumption?
Regional variation?
Cultural variation?
27. What About Water Use?
Is 55 gal/person/day a valid
assumption?
Difficult to accurately measure
water use!
Dilution, Dilution, Dilution
28. Can you Validate Removal?
I/A Septic System
Herein lies the rub!
Incoming I/A systems typically include
Wastewater some sort of effluent
recirculation back into the
septic tank, making it
Septic Tank
impossible to get a
Recirculation representative sample of
influent.
“Black Box”
Leach Field Alternative
Drainfield
31. Ultimately it all Boils Down to a
Homeowner and Their System.
Uncertainty in standard leads to compliance
enforcement difficulties!
Example 1 Example 2
A seasonal home typically occupied by A year-round home typically occupied
two environmentally-conscious retirees. by a family of four. They water the lawn,
They don’t water the lawn, installed installed water-saving devices but take
water-saving devices, take short long showers, do lots of laundry, have
showers, &c and have installed an I/A frequent guests and have installed an
system. I/A system.
Total Nitrogen numbers come back at Total Nitrogen numbers come back at
28mg/l, well in exceedance of 19mg/l. 14mg/l, below 19mg/l, but their water
Do you press compliance on the use is through the roof. You’ll probably
owners? never follow up on this system!
32. Can we “Shift the Curve”?
Can new
technologies take us
to the next level?
35. NitrexTM by Lombardo Associates
“Upwell” Class.
Presently available.
Generally expect TN < 5 mg/l, but
this system requires pretreatment
ahead in the treatment train to
nitrify ammonium.
From Recirculating Sand
House Filter
Nitrex
Filter
Septic Tank Pump
Chamber
Discharge
36. Membrane BioReactors (MBR)
Basic Concept
Submerse a hollow membrane inside an
aeration chamber.
Wastewater passes through
membrane leaving solids
behind
MBR Players
• BioMicrobics
• Puraflo
• Busse
• SJ Rhombus Air scours the membrane and keeps it clean
• Kubota (and supports micro-organisms)
38. More About MBR
MBR Produces a high quality effluent Potential Installation
with potential for reuse (very low
values for bacteria, BOD, and TSS)
39. Sequencing Batch Reactors (SBR)
Generally TN<15. Amphidrome Influent Effluent
Performance excursions Results TN (mg/l) TN (mg/l)
related to sludge buildup in Mean 36.8 15.0
primary tank. Median 37.0 14.3
Count 60 53
From
House Amphidrome by F.R. Mahoney
Associates
Amphidrome
Anoxic Tank
Clear
Unit
Well
Discharge
40. Composting and Urine Diversion Toilets
Composting Toilets Urine Diversion Toilets
Remove solids from Separates urine (and primary
wastewater stream. source of nitrogen) from
Still need to wastewater stream.
safely dispose Potential for recovery of
of greywater. nitrogen for re-use
41. Improving I/A and Onsite Monitoring
Developing next-generation tracking database to allow
for enhanced I/A compliance tracking abilities.
Expand database capability to
capture data on non-I/A systems.
Disseminate more information on
onsite performance.
42. In a Nutshell…
Currently installed I/A technologies remove about 50
percent of incoming nitrogen about 75 percent of the
time.
Careful monitoring can improve I/A performance.
Number of new technologies coming down the pipe
which may provide even better nitrogen reduction.
MASSTC continues to test the “latest and greatest” in
onsite technology.
43. More Information
MASSTC
www.masstc.org
BCDHE I/A Program
http://www.barnstablecountyhealth.org/ia-systems
Comparison of Costs for Wastewater Management Systems
http://www.ccwpc.org/images/educ_materials/wwreports/ca
pe_cod_ww_costs--4-10.pdf
44. Disclaimer: The presence of a product or service in the presentation is in no way
construed as an endorsement, advertisement or otherwise of that product or service.
45. Brian Baumgaertel
Environmental Project Assistant
Barnstable County
Department of Health and Environment