approach and impact on beneficial use of wastes · approach and impact on beneficial use of wastes....
Transcript of approach and impact on beneficial use of wastes · approach and impact on beneficial use of wastes....
1. Welcome
2. Housekeeping
3. Purpose of workshop
4. Introductions
5. Overview – setting the scene
6. Presentation – Dr Jo Cavanagh
7. Discussion
8. Other
OUTLINE
• Inform industry on the methodology being used to
develop appropriate soil contaminant limits.
• Provide opportunity for industry feedback on
proposed approach and how this may impact on the
beneficial use of organic wastes /materials.
• Determine how Ecological Soil Guideline Values can
most effectively be used to enable beneficial use of
organic wastes /materials.
PURPOSE OF WORKSHOP:
• NZ Biosolids Guidelines 2003
– Defined biosolids as any product that included WWTP sludge and met quality
standards
– Included soil replacement quality standards
– Did not consider non-biosolids quality to land
– Tighter default limits by 2013
– Expected to be reviewed within 5 years
• NZ Compost Standards 2005
– Contaminant limits link direct to NZ Biosolids Guidelines
• Other
– Waste Minimisation Act 2008
BACKGROUND – CONTAMINANT LIMITS
2013• Discussions between Water NZ, Centre for Biowaste Research,
WasteMINZ; joined by NZ Land Treatment Collective, Landcare Research and others
• Examination of issues – all organic wastes to land could have similar standards
• Why continue to deal with organic wastes independently?
BACKGROUND
Product As Cd Cr Cu Ni Pb Zn
Greenwaste &
foodwaste
14 1.1 30 56 37 100 280
Chicken manure 26 0.06 23 43 6 6 295
Pig manure 1 0.06 2 49 2 2 580
Horse manure 3 0.02 6 13 3 8 87
Sheep pellets 3 0.10 9 22 4 17 140
Mushroom compost 36 0.08 8 94 6 10 270
Biosolids
Guidelines (max)
20 1.0 150 60 60 250 300
HEAVY METAL CONTENT OF SOME ORGANIC MATERIALS
SETTING APPROPRIATE CONTAMINANT LIMITS
Protection:
• People
• Animals
• Soil biota
• Plants
• Ground water
• Surface water
• Other
Benefits:
• Maximise benefits
from organic
materials applied
to land
• Water NZ,
• Centre for Biowaste Research,
• WasteMINZ,
• NZ Land Treatment Collective,
• Landcare Research,
• MFE, MOH, MPI, MBIE
• Other
NEW GUIDELINES: ORGANIC WASTE MATERIALS GUIDELINES
PROJECT
Why do we need Eco-SGVs for NZ?
Arsenic Copper Zinc DDT
CCME 17 (SQeAR),
26 (SQeCI)
[12 (SQG)]
63 (AR),
91 (CI)
200(AR),
360(CI)
0.7(AR),
12 (CI)
Dutch 85, [IV 76] 96, [IV 190] 720, [IV 720] 4, [IV 1.7]
Biosolids 20 100 300 0.5
UK/EU - 88 90 0.15
US 18 (P), -(I),
(43 B, M)
70 (P), 80(I),
29 (B), 49 (M)
160(P),
180(I),
-,-, 0.023(B),
0.091 (M)
AR- Agricultural, residential,
CI – Commercial, industrial
P – Plant; I – Invertebrate; B – Bird; M - Mammalian
Why are they different?
• Data used
– Data availability, screening criteria
• Derivation methodology
– Method
– Data (e.g. EC10/EC30)
– Level of protection
Need an agreed approach
• Envirolink Tools project
• Funded by MBIE
• 2 yr project commenced July 2014
• Advisory group:
– Regional council SIG (contaminated land,
land monitoring, land managers group), MfE,
MPI
• Two components
– Background soil concentration
– Eco-SGV
Project overview
Deriving values - what to protect?
Soil
Priority contaminants• As, Cd, Cr, Cu, F,
Pb, Zn• ∑DDTs,
BaP/PAH, TPH• Additional
contaminants if sufficient resources
Timeline
• By end Oct 2014
– Agreed scope
• By Sept 2015
– Background soil concentrations determined
– Agreed methodology
• Stakeholder workshops using Cu and Zn examples
• June 2016
• Eco-SGV for up to 10 contaminants
Objectives
• Develop nationally agreed methodologies
– for determining background soil
concentrations of naturally occurring elements
– ecological soil guideline values (Eco-SGVs)
• Use existing data to determine background
concentrations and Eco-SGVs for multiple
land-use scenarios
• Develop clear guidance for applying Eco-
SGVs for different purposes to ensure they
are applied correctly.
Related guidelines
• Organic waste
guideline
– WasteMinz,
NZWater, CIBR,
LTC
• Aim is to
complement, not
conflict with these
guidelines
Aims of workshop
• Raise awareness of process to develop Eco-
SGVs and enable stakeholder input
• Clarify application of Eco-SGVs in relation to
organic wastes
– Helps define appropriate levels of protection
Application of Eco-SGVs
Contaminated land
managementProtection of soil quality
“Discharge shall not create a contaminated site*”
Remedial activities
Preventing soil
contamination
Identifying level of effect
*wording from Regional Council Plans
Specific applications
• Application of wastes to land
– Cleanfill, managed fill
– Biosolids, food waste, manures
• Fertiliser application?
• Contaminated land management
– Identifying level of effect
– remediation
Aim: no
restriction on
land-use as a
result of
activity
Aim:
minimising
harm,
improving
environment
Background concentrations + waste applied
= new concentrations �beneficial or detrimental effect?
• Recommendation:
– Adaptation of
Australian
approach to
derive Eco-SGV
Developing NZ-specific SGVs
Special Series: Ecological Soil Clean-Up Values for Metals
Landuse as a means to determine
level of protection
Land-useStandard % protection
Biomagnificationprotectiona %
Urban residential* 80 85b
Public open space 80 85b
Commercial 60 65c
Industrial 60 65c
Agricultural 95d and 80e 98c,e and 85c,e
National Parks 99 99
*Should residential include urban and rural?
Proposed approach…
• Adaptation of Australian methodology
• “Added risk” approach i.e.
– Eco-SGV=background + added concentration
Concept is that background concentration
have a negligible contribution to toxicity,
thus it is only the amount “added” that is
of concern
Proposed approach…
• Adaptation of Australian methodology
• “Added risk” approach i.e.
– Eco-SGV=background + added concentration
• Ageing/leaching
Toxicity tests are often performed using
metal salts, which are much more
“available” to be taken up by plants,
invertebrates etc (bioavailability) than
contaminants that have been in the soil
for long periods of time
Proposed approach…
• Adaptation of Australian methodology
• “Added risk” approach i.e.
– Eco-SGV=background + added concentration
• Ageing
• Normalisation to a reference soil (accounting
for bioavailability)
– pH – 5.5, Clay – 23%, CEC 21 cmol/kg, Organic
carbon – 5.5%.
• Species-sensitivity distribution if sufficient
data (statistics)
General Process
• Data collation
Soil
• Microbial processes
– Respiration, nitrification
• Plants
– Yield, growth,
germination
• Invertebrates
– Reproduction, growth
General Process
• Selection and standardisation of toxicity data
– Added concentration
Endpoint Comment
EC10, EC20, NOEC Minimal/no effect
EC30, LOEC Low level of effect
EC50 50% effect
General Process
• Ageing/leaching
• Normalisation to standard reference soil• “Typical NZ soil”
• pH – 5.5, Clay – 23%, CEC 21 cmol/kg, Organic carbon – 5.5%
• Background concentration +ACL = Eco-SGV
Discussion points
• How can Eco-SGVs most effectively be used
to enable beneficial use of organic wastes?
• When should they apply - to the waste
material? to the soil after application?
• What are the range of organic wastes to be
considered?
Discussion points
• Is the land-use specific approach useful for
developing Eco-SGVs?
• What is the appropriate level of protection?
• How practical are the derived values i.e. what
actions can be undertaken to ensure
compliance? And what are the costs of those
actions?
• Are the proposed soil characteristics of the
New Zealand soil appropriately
representative?
Background concentrations
• Development of Eco-SGVs
– Added-risk approach
• National Environmental Standard for assessing
and managing contaminants in soil
– Soil contaminant standards – As, Cd
– Doesn’t apply if background is higher than SCS
• Tiered Fertiliser Management System - Cd
• Cleanfill guidelines
– Background or background + ½ Eco-SGV
What influences background?
• Geology, pedology ……
……but what are the key influences?
• Approach: use spatial databases……
• S-Map, Land Resource Information, Q-Map
• … and existing data to identify key influences
– Analysis at national scale, primarily regional
council data
– Focussed Southland/Otago (GNS Science)
Further analyses
• Testing spatial autocorrelation
• Examine influence of soil texture
• Where landuse is a significant influencing
factor, reanalyse data subset
• Focussed Otago/Southland data
Developing SGVs for Cu and Zn
• Data collation
– Primarily data collated for Australian and EU
– Literature search for new studies
– (still some additional studies to include)
• Normalisation of toxicity data to NZ soil
– Normalisation relationships from a number of
recent studies specifically focussed on looking
at factors influencing technology
– CEC, pH primary factors influencing toxicity
Protection level
ACL (95%confidence limits) for different toxicological endpoints
EC10fresh EC10aged EC30fresh EC30aged EC50fresh EC50aged
99% 34
(26- 51)
60
(45-88)
70
(53-96)
127
(98-170)
110
(77- 162)
203
(152- 281)
95% 50
(39-71)
85
(66-119)
98
(79-131)
173
(141-221)
156
(120- 214)
277
(222-359)
90% 63
(49-88)
106
(84-143)
121
(100-155)
210
(174-259)
192
(150-255)
335
(277-424)
80% 85
(67-115)
142
(113-187)
161
(132-207)
272
(228- 340)
256
(204-340)
434
(364-543)
60% 139
(107-189)
226
(172-298)
251
(191-339)
409
(324-549)
404
(315-536)
653
(517-837)
Copper – added contaminant limit
Zinc – added contaminant limit
Protection level
ACL (95%confidence limits) for different toxicological endpoints
EC10fresh EC10aged
EC30fresh EC30aged EC50fresh EC50aged
99% 29
(3.5-38)
84
(14-117)
44
(6-58)
127
(17-175)
84
(14-119)
255
(36-345)
95% 44
(21- 56)
131
(76-167)
66
(33-85)
197
(101-257)
131
(76-170)
393
(201-501)
90% 56
(43 74)
169
(134-219)
84
(65-115)
254
(194-344)
169
(133-229)
506
(391-672)
80% 78
(62 120)
237
(186-369)
117
(91-186)
355
(276-552)
237
(185-379)
709
(553 1124)
60% 130
(117-250)
397
(362-775)
196
(171-370)
593
(485-1128)
397
(363-775)
1185
(1025-2275)
Final Eco-SGVs
• Background concentration + added value
• What value of background
– Median
– 95th percentile
• Cu – 5-20 mg/kg (all landuses)
• Zn – 20-30 mg/kg (background,forestry)
The special case of Cu and Zn
Best remedial option is to actively manage soil to
encourage healthy soil community (provided off-site
risks managed)
High toxicity to ecological receptors
Ecological risk more likely to drive any remedial actions
Low toxicity to people
Essential elements – used by organisms to growBUT
Other contaminants
• Contaminants covered within Tools project
• As, Cd, Cr, Cu, F, Pb, Zn
• ∑DDTs, BaP/PAH, TPH
• Additional contaminants if sufficient resources
• Aim of project is to develop methodology
such that Eco-SGVs can be developed for
additional contaminants
• Emerging contaminants….
Emerging contaminants
• Typically organic compounds
– Wide range currently in use for different
purposes, pharmaceutical and personal care
products, plasticizers (e.g bisphenol A), anit-
microbial (e.g. triclosan), industrial
components
– Typically present in low concentrations, level
of effect often unknown
• Challenging to develop Eco-SGV due to
limited data
Discussion points
• How practical are the derived values i.e. what
actions can be undertaken to ensure
compliance? And what are the costs of those
actions?
• Is there room for consideration of different
values for the use of organic waste for the
improvement of degraded land?
• Priority contaminants for organic waste
Databases
• S-Map, Land Resource Information, Q-Map
• Pedological and geological information
• 1:50 000
• 30% coverage across NZ