Derivation and Application of Water Quality Guidelines (WQGs)

Graham Merrington1, Adam Peters1, Michael Warne2 1WCA Environment, Farrington, United Kingdom 2Centre for Agroecology, Water and Resilience, Coventry University, United Kingdom

2nd International Conference on Deriving Environmental Quality Standards for the Protection of Aquatic Ecosystems (EQSPAE)

Hong Kong - 18 June, 2016 Site-Specific Guidelines

Ecosystems and environmental conditions vary across country, limiting applicability of generic WQGs • If there are elevated natural background levels of the substance. • If there are atypical levels of variables that can influence the bioavailability and/or toxicity of the substance. • If the sensitivity of resident species needs to be considered. • If you already have good site-specific data. • If you need coherence with guidelines for another media. • If there is recent scientific advancement. • If you want to do better than the generic guideline. Remember: higher or lower value may result

2 Site-Specific Guidelines

Science-based Factors Policy-based Factors • Socio-economic considerations • Physical-chemical parameters (e.g., pH, temperature, water • Desired level of protection hardness, dissolved oxygen, • Management goals for various DOC…) water uses (most sensitive) • Presence/absence of species of • End-of-pipe discharge limits interest/concern • Technology • Sensitivity of resident • Others organisms • Chemical inter-actions • New toxicity data available • Others

3 Site-Specific Guideline Development

• Substances affected: – Metals - strongly & frequently – Inorganics - somewhat – Organics - some more, some less – Pesticides - less often & to a lesser degree

4 Developing SSGs

• Process can be more complicated than for generic WQG • May need to balance science with social and economic considerations • Requires knowledge of physical, chemical and biological characteristics of local water body

5 Potential Approaches for SSGs

• Physico-Chemical Adjustment • Natural Background Concentration • Recalculation Water Effect Ratio • • Procedures are not mutually • Resident Species exclusive (i.e., may be combined) • Choice depends on particular situation

6 Physico-Chemical Adjustments

• Adjust WQG to local condition by using toxicity modifying factors • Recognizes that physical or chemical factors can modify toxicity or bioavailability of substances • Toxicity proportional to concentration at biotic receptor (see e.g., BLM) • Utilizes generally-applicable relationships &local data to adjust national WQG value to specific locale

7 Physico-Chemical Adjustments (cont.’d)

• Toxicity Modifying Factors: – pH (e.g., in CWQG: ammonia and aluminium) – Temperature (e.g., in CWQG: ammonia)

– Hardness (CaCO3) for some metals (e.g., in CWQG: Cd, Cu, Pb, Ni) – Others e.g., suspended solids, TOM/DOM, TOC/DOC, DO, counter-ions (chloride, sulfide, ..)

– salinity Factor can have an • See BLM - Cu, Ag, Ni, Zn, Pb positive or negative effect on toxicity! • Others: ionic organics & inorganics

8 Physico-Chemical Adjustments Methodology

• To develop: Requires toxicity data on multiple species over a range of conditions to quantify the relationship – E.g., USEPA guidance on hardness – Data requirements are extensive if there are multiple toxicity modifying factors – Statistics can be complicated • To apply: Requires concurrent measurement of substance of concern and modifying parameters at collection site – If data not available, could use average concentrations or substitute (i.e., alkalinity for hardness, multi-year averages)

9 Points to Consider

• Data needs • Existing TMF relationships may be over- simplified • Acute / chronic extrapolation • Often only single parameter • Limited validation

10 Recalculation Approach

• Recalculate WQG using only existing toxicity data from local species • Species used in creating national WQG may be absent from water body you’re considering • Review national dataset – Ensure all species in dataset occur locally – Ensure local sensitive species are considered – Examine recent literature for relevant data • Recalculate guideline

11 Points to consider

• Need toxicity data on locally relevant species • Need enough quality data to provide confidence in guideline developed

• If data are insufficient, need to generate new toxicological data (i.e., => resident species approach)

12 Points to consider (cont.)

• Recalculation is a “desk top” method to derive SSG – If sufficient toxicity dataset is available, with appropriate taxonomic representation • Opportunity to improve confidence in guideline value BUT • Ubiquitous presence of many commonly tested species (many of whom sensitive) may render recalculation exercise unnecessary • If dataset is reduced, confidence in guideline can decrease

13 Water Effect Ratio (WER)

• Considers Direct Toxicity Assessment (DTA) • Difference of toxicity between site water and laboratory water • Use WER to adjust the generic WQG relative to the observed toxicity at a given site • Can only apply WER to generic WQGs that were created using lab-derived aquatic toxicity test data (i.e., not field-based WQG)

14 WER - Points to consider

• US EPA method; CCME also provides guidance • Requires testing with at least one fish, one invertebrate, more recommended • Consider issue of acute & chronic tests • limited availability of appropriate test organisms • Conduct side by side tests on site water and lab dilution water on most sensitive species – Lab water should be equivalent to water used in the critical test to derive the generic guidance

15 Calculating the WER

• WER= Endpoint from site water test Endpoint from lab water test • Calculate WERs for as many species as possible • SSG = Geometric mean of WER Values x Generic Water Quality Guideline

16 WER - Summary

• WER recognizes that toxicity in site water differs from toxicity in lab water – Net toxicity calculated without requiring knowledge of detailed processes • Can result in SSG that can have a high degree of confidence BUT • Requires considerable effort and cost to develop • Can be spatially and/or temporally specific • Can be costly

17 Resident Species Approach

• Also considers DTA • Calculate SSG using existing and new toxicity data from local species • Combines aspects considered in Physico- chemical, Background, Water Effect Ratio & Recalculation methods • Test variety of locally relevant species under site-specific conditions

18 Points Consider

• Great results, but expensive • Limited guidance on approach available – Determine type and number of tests • Seasonality? – Select test species: • Suitably sensitive? • Appropriate endpoints? • Can organism be tested in lab? • Generate site-specific dataset 19 Challenges to Resident Species Approach

• obtaining enough test organisms at the right life stage – Especially if species at risk or extirpated – maintaining health of organisms (not typical lab. species) • Expensive and time-consuming – Example: River headwaters in Idaho (Dillon and Mebane 2002) • 14 species • 140 site-specific toxicity tests • Five years to develop (1996-2001)

20 Direct toxicity assessment (DTA) • Integrates toxicity of mixtures • Similar to WER & Resident Species – local species and water – clean reference water – lab testing; in-situ; community – suite of species

21 Implementing WQGs in Aus and NZ

• Aus & NZ WQGs have no legal standing • Numerical limits are referred to as Trigger Levels (TVs) • It is not a “pass or fail” system

< TV = low risk of TV for > TV = moderate to contaminant adverse effects to A high risk of adverse biota effects to biota further action is triggered

22 Optional decision tree for toxicants

Compare concentration to trigger value Above (moderate to high risk) Below Conduct site-specific investigation

Compare measured concentration with new site-specific trigger value Above (moderate to high risk) Below Perform direct toxicity assessment Non- Toxic (moderate to high risk) toxic Management action required to reduce pollutant concs - PRPs

Low risk PRP = Pollution reduction program No action required 23 Decision framework for toxicants

Compare measured concentration against guideline trigger value Below Above Low risk Consider site-specific factors that modify trigger value

Compare measured concentration with new site specific trigger value

Below Above Low risk Perform direct toxicity assessment Non- toxic Toxic Low risk High risk 24 Decision Tree for Metals in Waters

Acid-soluble Metals Analysis (hardness correction for freshwaters)

Below Above

Biological Dissolved Metals Analysis effects (0.45 or 0.22 µm membrane filtration) unlikely Below Above

Biological Speciation effects Measurement of pH, DOC etc unlikely Speciation modelling Chemical measurements Toxicity testing 25 Example of copper in freshwater

Step 1: Total copper: hardness correction Step 2: Dissolved copper Filtration or ultrafiltration Step 3: Speciation considerations • Speciation measurements using ASV • Modelling calculations (PHREEQE 96)

Cu bioavailability confirmed using toxicity test with a sensitive organism (e.g. green alga)

26 ResultsCopper of site in-specific Freshwater investigation (90mg/LCaCO3) for Cu 16 14.5

12

HMTV = 3.5 ug/L 8 6.4 TV = 1.4 ug/L

4

2 1.8

0 TotalTotal Cu Cu Dissolved Cu ASVASV Cu PHREEQ Model Dissolved Cu PHREEQ Cu Step in Decision Tree

27 Example of deriving a site-specific EQS

28 Determining a ‘safe’ dilution factor for the saline return water from the proposed Olympic Dam mine expansion desalination plant

Michael Warne1, Jill Woodworth2*, Dustin Hobbs3, James Brook4 1 CSIRO, 2 Geotechnical Services Pty Ltd, 3 Hydrobiology Pty Ltd, 4 ARUP/AECOM,* current address GHD.

29 The proposed expansion of Olympic Dam

• Olympic Dam is the worlds 4th largest known copper and gold deposit and the largest known uranium deposit • Currently mined underground • Proposal is to expand the mine – develop an open pit mine • This will increase production 6-fold • Make it one of the world’s largest mines • Expanded mine will require a max additional 200 ML/d (Adelaide (pop 1.2 million) uses on average 374 ML/d) & the best option was considered to be a desalination plant

30 Location of the desalination plant

X Olympic Dam mine Aquaculture leases Desalination plant Australian giant cuttlefish breeding ground (red) Intake Whyalla

Oil refinery Adelaide Discharge point

Point Lowly 31 Jetty Objectives of this project

• To assess the toxicity of the saline return water (SRW) to organisms representative of those found in Spencer Gulf

• To determine the dilution of the SRW required to protect aquatic ecosystems in the Spencer Gulf

• To determine if discharging the SRW will effect the Australian giant cuttlefish (Sepia apama)

The ecotoxicology work is only one part of a weight of evidence approach

32 Test organisms 1 2 A total of 15 species used in WET tests 10 species selected to determine safe dilution factor 1.Microalga - Isochrysis galbana (72-h growth) 2.Macroalga - Ecklonia radiata (72-h 3 germination) 3.Macroalga - Hormosira banksii (72-h germination) 4 4.Copepod - Gladioferens imparipes (28-d reproduction) 5 6 5.Western King Prawn - Melicertus latisulcatus (21-d juvenile growth) 6.Pacific Oyster - Crassostrea gigas (48-h larval development) 7 7.Snapper - Pagrus auratus (7-d larval growth) 8 8.Mulloway - Argyrosomus japonicus (7-d larval growth) 9.Yellowtail Kingfish - Seriola lalandi (7-d larval growth) 10.Australian Giant Cuttlefish - Sepia apama 9 10 variety of endpoints and durations 33 Toxicity data used to calculate safe concentration Test species Taxonomic gp EC10 and NOEC values (% brine) Best dataset 2nd best dataset H. bansksii macroalga 16 I. galbana diatom 84.4 84.4 E. radiata macroalga 27.6 27.6 C. gigas bivalve 3.3 3.3 G. imparipes crustacean 10.9 P. auratus fish 22.2 22.2 S. lalandi fish 10.6 A. japonicus fish 11.6 11.6 M. latisulcatus crustacean 11.8 7.5 S. apama cephalopod 6.3 6.3 No. species 7 10 No. taxa gps 6 6 34 Results of the species sensitivity distribution (SSD) analysis - I

Best dataset 2nd best dataset

PC95 = 3.4 % SRW PC95 = 4.1 % SRW PC99 = 2.4 % SRW PC99 = 2.5 % SRW

The best dataset required a lower percentage of saline return water (SRW) even though it is based on less species

35 Calculation of dilution factors

• The dilution factors (DF) are calculated by:

DF = 100 / PCx

where PCx could be any Protective Concentration eg. PC99 or PC95. Dataset PC values % SRW Dilution Factor*

Best 95 3.4 29

99 2.4 42

2nd best 95 4.1 24

99 2.5 40

36 * These are not the final dilution factors – there is ongoing assessment WQGs that account for toxicity- modifying factors

• Generally the only ones are for metals modified by hardness; • Some CWQG use pH and temperature (e.g., ammonia) • For others just have qualitative statements • More WQGs modified for factors should be derived e.g. organics and OC content

37 Soil quality guidelines matrix See WQGs for ammonia • Soil quality guidelines in Flanders and Aus have Soil Quality Guidelines that are modified by soil physico- chemical properties (pH, CEC, OC, clay content) and that take account of ageing and leaching • Germany and some others account for soil type (clay, loam, sand) CEC

pH 5 10 20 30 40 60 4 27 44 72 96 118 157 5 51 83 135 180 220 290 6 95 155 252 335 410 545 7 178 290 470 625 765 1020 7.5 245 395 645 855 1045 1390 38