Saving Soil: Biosolids Recycling in New England

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Biosolids Management in New England
presented to
Nova Scotia Ministry of Environment & Labour
Forum on Biosolids Science
June 13, 2005
Ned Beecher, Executive Director, NEBRA
bi s lids…
biosolid n. (1990): solid organic matter
recovered from a sewage treatment
process and used especially as fertilizer -usually used in plural
--Merriam-Webster’s Collegiate Dictionary, 10th Ed.
biosolids: plural noun: organic matter
recycled from sewage, especially for use
in agriculture
--New Oxford Dictionary of English, 1998
Outline of presentation
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Biosolids management & trends
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Examples of current operations & uses
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U. S.
New England
Class B: farm uses (lime treated, anaerobic)
Class B: land reclamation (lime treated, anaerobic)
Class A: bulk advanced alkaline treatments
Class A: heat dried pellets
Class A: compost
Issues & challenges
Biosolids management & trends…
United States…
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About 16,000 wastewater treatment facilities.
Produced ~ 6.9 million tons in 1998 (EPA, 1999)
~ 60% applied to land in 1998 (EPA, 1999)
Estimated 7.1 million tons in 2005, 66% to land?
Majority is Class B land applied, but trend is to more
Class A
Public scrutiny and concern increasing some
Improving products & practices
History of U. S. Federal Regulations
- “Part 503”
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Clean Water Act Section 405 – risk-based limits for pollutants
“which may adversely affect public health and the environment”
Round One (final rule 2/93) – pollutants for which information
initially available; screened 350+ pollutants
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Developed with input from researchers around the country
Self-implementing
Several management requirements
Similar pathogen & vector attraction-reduction as before (Part 257)
Pollutant limits based on risk assessment (metals, chemicals)
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Land application: limits for 9 metals
Surface disposal: limits for 3 metals
Incineration: limits for 7 metals and total hydrocarbons
1996 review by National Academy of Sciences: “negligible risk”
Case for Caution by Harrison et al. (1999), plus other critiques
How safe to be? Risk assessment vs. precautionary
History of U. S. Federal Regulations (cont’d)
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Part 503 round 2 – additional pollutants (31) examined based on
new information available
Dioxins and related compounds targeted
2001 & 2002: dioxin not to be regulated for surface disposal,
incineration, and land application
Inspector General: EPA does not have information to determine if
human health & environment are protected
2002 review by National Academy of Sciences: no document
harm, but persistent uncertainties and need for updated science
Research proceeding (WERF, EPA bioaerosols, Sustainable Land
Application conference (JEQ)
Biosolids management & trends…
New England Data (2000)
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Most U. S. states have own, more stringent regulations
About 600 publicly owned wastewater treatment facilities
in New England
Produce approximately 434,000 dry tons of sewage
sludge.
96,000 dry tons (22%) of regional sewage sludge is
recycled as biosolids fertilizer & soil amendment products
About 18% was treated to Class B standards; 82% treated
to Class A
New England more densely populated, less agriculture
(from Saving Soil: Biosolids Recycling in New England, a
2001 NEBRA report from www.nebiosolids.org)
New England Data (cont’d)
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Estimated 3.7 million lbs (est.) nitrogen from
96,000 dry tons recycled biosolids in 2000.
Equivalent chemical fertilizer nitrogen would
have cost an estimated $1.3 million in 2000
(more now, as N fertilizer prices are up).
96,000 dry tons of biosolids would have
required 350,000 cubic yards (est.) of landfill
space – equivalent of 6 landfills each the size
of a football field & 33 feet deep!
New England Data (2000, VT 1999)...
New England Biosolids Recycling
Rates (2000 data)
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ME – 77% (treated for beneficial use in agriculture &
general landscaping); Class B declining
VT – 75% (primarily through composting, much of this in
Quebec)
NH – 30% (down from 50% in 1996 mainly due to stricter
state & local land application regulations)
MA – 20% (almost all Class A material including Boston’s
MWRA heat dried “Bay State Fertilizer”); this has increased
since 2002 with Greater Lawrence heat dried
CT & RI – each below 10%, composted
Compost markets are strong & growing
Maine (2004 data, ME DEP)
Tot. cu.yds.compost OR NViro: 93,622 (72,693
cu. meters)
Tot. cu.yds. stockpiled: 2,618 (2,033 cu. meters)
Tot. cu.yds. landfill: 32,989 (25,614 cu. meters)
Tot. cu.yds. out-of-state: 18,114 (14,065 cu.
meters)
Tot. cu.yds. other use: 0
TOTAL ALL: 168,824 cu. yds (131,084 cu. meters)
~30,000 dry tons (~27,000 metric tonnes)
Diverse Biosolids Uses
Spectacle Island, Harbor Islands National Park, Boston Harbor
Photos : New England Organics, Inc.
Bulk / Class B programs...
• 2001: Nashua changes from
disposal at landfill to recycling,
with new anaerobic digester
• The digester complex generates
electricity, reduces amount and
odors of biosolids, and saves
ratepayers about $750,000 a year in
operating costs.
• Class B biosolids used on farms
• Boston also uses egg-shaped
digesters and recovers energy
Bulk Class A & B, lime-treated, Concord, NH biosolids are
applied to local fields growing feed corn for dairy cows.
Ogunquit, Maine specialized town truck to topdresses Ogunquit Class B biosolids on nearby farm
fields for grass hay.
Land Reclamation
a two-year-old NH reclaimed gravel pit
the “manufactured topsoil” develops
a sustainable soil ecosystem
a one-year-old NH reclaimed gravel pit
Keene, NH
Landfill
after capping
with
manufactured
topsoil
Keene, NH
September,
2001 photo
Photo: Keene / Resource Management, Inc.
(from the First Annual New England Biosolids Parade - www.nebiosolids.org)
Class A programs
Massachusetts
Water
Resources Authority
Deer Island WWTF
Boston Harbor
Photo: MWRA
Egg-shaped digesters treat
the sewage sludge from
Boston and 42 other
communities before it is
heat-dried and pelletized
to make a fertilizer
product.
(from the First Annual New England Biosolids Parade - www.nebiosolids.org)
Massachusetts Water
Resources Authority
and
New England Fertilizer
Company (NEFCO)
Quincy, MA
Operations Commenced
December, 1991
Biosolids Drying and
Pelletizing to Produce a
Slow-Release Fertilizer
(from the First Annual New England Biosolids Parade - www.nebiosolids.org)
Greater Lawrence
Sanitary District
and
New England Fertilizer
Company (NEFCO)
North Andover, MA
Operations Commenced
December, 2002
Biosolids Drying and
Pelletizing to Produce a
Slow-Release Fertilizer
(from the First Annual New England Biosolids Parade - www.nebiosolids.org)
NEFCO ships to Florida to fertilize orange trees and to the
Midwest for fertilizer blending and to Colorado for use on
ranches and…
...some MWRA uses right close to
home...
Castle Island, South Boston
The Esplanade
along the
Charles River
is fertilized
with Bay State
Fertilizer.
Photos : MWRA.
NViro Soil (Class A alkaline treated)
Innovative Earth Solutions /
Soil Preparation, Inc.
Plymouth, Maine
Merrimack, NH biosolids compost
Merrimack, New Hampshire
Nourishing Green Parks and Fairways
The Great Lawn, Central Park NYC
New England Golf Course
Photos: Merrimack / Agresource
Hawk Ridge in Unity, Maine
Largest private composting
operation in New England
More composting...
Photo: Agresource.
Ipswich, MA Agresource compost operation.
Williamstown, MA
Composting
biosolids produces a
Class A biosolids
product that can be used
anywhere...
A Maine
outdoor
“windrow”
biosolids
compost
operation.
LAWPCA
Compost Facility
Auburn, ME
1988 - present
Sited with plenty of space around it,
this biosolids compost facility
has operated steadily since the
late 1980s.
Lewiston-Auburn Water
Pollution Control Authority
Lewiston-Auburn, ME
(from the First Annual New England Biosolids Parade - www.nebiosolids.org)
GSI Compost Facility
Near Sherbrooke, QU
September, 2002
Wastewater solids from around
northern New England,
including all of the Burlington
area, is composted in
Quebec and made into
various soil amendments
and products.
GSI Environnement
Sherbrooke, QU
(from the First Annual New England Biosolids Parade - www.nebiosolids.org)
More compost uses...
Maine’s
Colby
College
uses
biosolids
compost
on sports
turf.
Photo: New England Organics
Photo: Agresource.
…sports fields... A Tufts University football
field is topdressed with biosolids compost.
…and
wetlands...
This
constructed
wetland along
a NH highway
has soil made
with biosolids
compost.
Current issues / concerns
Sewage sludge contains more than just
human waste; it also contains…
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“heavy” metals
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chemicals
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pathogens (disease-causing microorganisms) mostly in Class B
Sewage sludge and biosolids can have odors
Political landscape
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Some political interest at national & state levels
EPA Office of Inspector General, National
Academy of Sciences reports
About 17% of NH towns have severe restrictions.
A few Maine and Massachusetts towns too.
Attempts nationally and in states for stopping land
application have failed (e.g. Center for Food
Safety petition to EPA, but state & local
regulations have gotten stricter)
Responding to concerns...
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Public concerns are legitimate--people don’t know
much about this specialized field and initial negative
reactions are natural
People need time to absorb new information
Some biosolids management programs are getting
more sensitive, involving the public more
Improving practices
National Biosolids Partnership - EMS
Current state of the science
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Large amount of research behind current biosolids management
practices & regulations
EPA Risk Assessment - 503 Rule (with W-170 input)
Several long-term studies: e.g. Pennsylvania land reclamation,
Rosemount farm use, Chicago Prairie Plan, King County forests
Review by the National Academy of Sciences 1996
Review by the National Academy of Sciences 2002
Every decade “state-of-the-science” conference (last in 2004)
BUT there are still going to some questions regarding risks of biosolids
management: currently odors/bioaerosols, ecological impacts of trace
chemicals (PDBEs, endocrine disruptors)
Bottom line (my opinion)
On-going scientific research and debate are
necessary and should continue, but…
…decades of experience and research have led many
knowledgeable researchers to conclude that
current best biosolids management practices
represent relatively low risk to public health and
the environment.
But it has to be done right
and assurance of that is key!
Thank you!
New England Biosolids and Residuals Association
P. O. Box 422 / Tamworth, NH 03886 USA
phone 603-323-7654 / info@nebiosolids.org
www.nebiosolids.org
Cooperatively promoting the environmentally
sound recycling of biosolids and other residuals.
N.E. Trace Metals Averages
Nova Scotia Guidance (May 04)
Trace Metals Limits (mg/kg dry weight)
Metal
Exceptnl
Quality
Class A / B Compare NH Standard
(regular / low metals)
Arsenic
13
75
32 / 10
Cadmium
3
20
14 / 10
Chromium
210
1060
1000 / 160
Cobalt
34
150
Not regulated
Copper
400
760
1500 / 1000
Mercury
0.8
5
10 / 7
Molybdenum
5
20
35 / 18
Nickel
62
180
200 / 98
Lead
150
500
300 / 270
Selenium
2
14
28 / 18
Zinc
700
1850
2500 / 1780
N.E. trace metals of greatest
environmental concern: arsenic (As)
Cha rt 3.12 : Average Conc entrations of Arsenic in
New England Bios olids
2000
New Hampshire
1999
Maine
1998
Mass ac husetts
1997
Vermont
1996
Federal
Standard
1995
1994
0.00
5.00
10.00
15.00 20.00
25.00
30.00
Par ts pe r m illion (m g/k g)
35.00
40.00
45.00
NOTE: Federal U. S. standards shown for comparison are the
strictest (EQ) standards. NS guidelines EQ = 13 ppm
N.E. trace metals of greatest
environmental concern: cadmium (Cd)
Cha rt 3.13 : Average Conc entrations of Cadm ium in
New England Bios olids
2000
1999
New Hampshire
Maine
Mass ac husetts
Vermont
Federal Standard
1998
1997
1996
1995
1994
0
5
10
15
20
25
Par ts pe r m illion (m g/k g)
30
35
40
NOTE: Federal U. S. standards shown for comparison are
the strictest (EQ) standards. NS guidelines EQ = 3 ppm.
N.E. trace metals of greatest
environmental concern: lead (Pb)
Chart 3.1 4: Average Concentra tion s of Lea d in
New Engl and Bioso lids
2000
1999
New Hampshire
Maine
Mass ac husetts
Vermont
Federal Standard
1998
1997
1996
1995
1994
0
50
200
150
100
Par ts pe r m illion (m g/k g)
250
300
NOTE: Federal standards shown for comparison are the
strictest (EQ) standards. NS guidelines EQ = 150 ppm.
N.E. trace metals of greatest
environmental concern: mercury (Hg)
Chart 3.1 5: Average Concentra tion s of Mercu ry in
New Engl and Bioso lids
2000
1999
New Hampshire
Maine
Mass ac husetts
Vermont
Federal Standard
1998
1997
1996
1995
1994
0
3
6
9
Par ts pe r m illion (m g/k g)
12
15
NOTE: Federal standards shown for comparison are the
strictest (EQ) standards. NS guidelines EQ = 0.8 ppm.
18
Trace metals in other agricultural
materials, for comparison
Chart 3.2: Reported Averages (or Ranges) of Trace Metals Levels in Other Materials (ppm or mg/kg)
Dairy
Ma nure (4)
Dairy
Ma nure (3)
Feedl ot
Ma nure (2)
Pig
Waste (2)
Swine
Ma nure (3)
Poultry
Litter (2)
Chicken
Ma nure (3)
Arsenic ( As)
0.26
0.88
NA
3.7
NA
30
0.66
Cadmium (Cd)
0.32
0.03
0.2
ND
0.32
ND
0.59
Chromium ( Cr)
5.2
20
NA
61
NA
20
4.9
Copp er (Cu)
41
11.6
2.0
501
14.3
1195
13
Lead (Pb)
6.6
2.1
0.2
ND
1
12
11.5
Mercury (Hg)
0.09
0.05
NA
ND
NA
NA
0.04
Molybdenum (Mo)
2.5
22.1
NA
7.9
22.6
NA
95.3
Nic kel ( Ni)
7.8
3.3
NA
29.3
NA
NA
3.9
Selenium (Se)
0.5
NA
5000
ND
NA
NA
NA
Zinc (Zn)
215
21
8
656
60
631
297
Trace Metal
Calculating
Accumulation
of Metals in
Soils From a
Typical Bulk
Biosolids
Application
Typical chemicals of possible concern
Chemical Content of Sludge/Biosolids
(from Carpenter, 2000)
Sludge is engineered to capture…
• organic matter
• nutrients (especially nitrogen and phosphorous)
Sludge also favors retention of
• insoluble compounds
• non-, or semi-volatile compounds
• non-readily degradable compounds
• compounds that are strongly sorbed to organic matter
In some cases, the management of wastewater treatment plants may result
in sludge containing metabolites of organic matter decomposition
In many ways, the chemical quality of sludge is representative of the the
chemical quality of our environment
Dioxin Concentrations in Biosolids
(from Carpenter, 2000)
Sampling
years
Number of
samples
Mean
Median
ppt (dry weight)
Maine
1995-1997
31
6.3
5.4
New Hampshire
1999/2000
95
5.2
3.5
Vermont
1997
28
11.2
8.6
NSSS
1988
208
831
371
1 Data taken from Jones, K.C. and A.P. Stewart 1996. Dioxins and furans in sewage sludges
2 Non-detects were reported as 1/2 the detection limit when calculating TEQ values
Pathogens
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Public concern, especially emerging pathogens
Advances in detection & science
A focus of the 2002 National Academy of Sciences review
Continued research needed & expected
Current treatment technologies likely to treat for emerging
pathogens also
Most exposed are operators; public much less exposed
(although exposures may not be comparable)
Be concerned about neighbors - best management needed
Ensure proper treatment!
Odors/Bioaerosols
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A common trigger of public concern
Current research identifying specific compounds
(EPA/USDA) and potential effects
Enforcement & Oversight
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Critical for public confidence
Independent oversight / local involvement
Reviewing policy… look at scientific summaries.
In 1996, the lead U. S. scientific body, the National Academy of
Sciences, reviewed biosolids recycling and concluded:
“In summary, society produces large volumes of treated municipal
wastewater and sewage sludge that must be either disposed of or
reused. While no disposal or reuse option can guarantee complete
safety, the use of these materials in the production of crops for
human consumption, when practiced in accordance with existing
federal guidelines and regulations, present negligible risk to the
consumer, to crop production, and to the environment.”
U. S. National Academy of Sciences 2002 review:
“There is no documented scientific evidence that the Part 503 rule
has failed to protect public health. However, additional scientific
work is needed to reduce persistent uncertainty about the potential
for adverse human health effects from exposure to biosolids. There
have been anecdotal allegations of disease, and many scientific
advances have occurred since the Part 503 rule was promulgated.
To assure the public and to protect public health, there is a critical
need to update the scientific basis of the rule to (1) ensure that the
chemical and pathogen standards are supported by current scientific
data and risk-assessment methods, (2) demonstrate effective
enforcement of the Part 503 rule, and (3) validate the effectiveness
of biosolids management practices.”
Thank you!
New England Biosolids and Residuals Association
P. O. Box 422 / Tamworth, NH 03886 USA
phone 603-323-7654 / info@nebiosolids.org
www.nebiosolids.org
Cooperatively promoting the environmentally
sound recycling of biosolids and other residuals.
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