The pollution prevention paradigm in British Columbia can be represented spatially by the following points:

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1 DATE February 27, 2015 REFERENCE No. TO Mr. Scot MacKillop LNG Canada Development Inc. FROM Barbara Wernick LNG CANADA LOAD SITE: ASSESSMENT OF POTENTIAL WATER QUALITY EFFECTS FROM INDUCED TOTAL SUSPENDED SOLIDS WITH ASSOCIATED POLYCYCLIC AROMATIC HYDROCARBONS 1.0 INTRODUCTION Golder Associates Ltd. (Golder) is pleased to provide LNG Canada Development Inc. (LNGC) with the following analysis of the environmental fate of contaminants associated with proposed dredging of sediment from the LNGC Project at Kitimat, BC. This technical memorandum presents methods and results of a desktop analysis undertaken to evaluate the potential for polycyclic aromatic hydrocarbons (PAHs) to be present in the water column as a result of dredging and to subsequently cause toxicity. The analysis incorporates relevant and available site data and adopts a number of conservative, simplifying assumptions to simulate a potential worst case scenario of PAH release into the water column. Other contaminants of potential concern are not included in this assessment either because the existing concentrations at the disposal site are similar to (copper) or higher than (dioxins and furans) the expected quality of the material to be disposed of at sea. As well, the mode of toxicity of dioxins and furans is through bioaccumulation rather than direct toxicity. 2.0 BACKGROUND The pollution prevention paradigm in British Columbia can be represented spatially by the following points: Point of discharge - For a typical discharge situation, the effluent at the end-of-pipe should not be acutely lethal, which is often operationally defined by Environment Canada (e.g., via statutes such as the Metal Mining Effluent Regulations [MMER]) and the British Columbia Ministry of Environment (BC MoE) (e.g., via the Municipal Wastewater Regulations) as 96-h LC50 100% for rainbow trout. These effluent permitting tests can also be performed with a marine fish such as 3-spine stickleback for marine receiving environments. In a dredging scenario, there is no physical pipe to which effluent limits may be applied. Borrowing from the MMER a reasonable operational definition, the discharge point is the point at which the operator ceases to exercise control over the effluent, for example at the edge of a silt curtain. Golder Associates Ltd. 2 nd Floor 2920 Virtual Way, Vancouver, British Columbia, Canada V5C 6C6 Tel: +1 (604) Fax: +1 (604) Golder Associates: Operations in Africa, Asia, Australasia, Europe, North America and South America Golder, Golder Associates and the GA globe design are trademarks of Golder Associates Corporation.

2 Initial dilution zone (IDZ) Both federal and provincial statutes exert legal control over discharges at the point of discharge. The provincial paradigm further uses a dilution zone to provide a structured approach to assessing impact. The size of the IDZ is often defined as 100 m from the point of discharge, although there is flexibility in the actual distance applied to a given project or activity. The IDZ is the point at which chronic, 30-day average ambient water quality guidelines (WQGs) are generally expected to be met. WQG are typically derived from: conservative endpoints (e.g., lowest observed effects concentrations or LOECs); the most sensitive species for which toxicity test data are available; and safety factors (often 10 times) are applied to add conservatism. Thus, exceedance of a guideline should not be interpreted to mean an effect will necessarily occur. Receiving environment In the receiving environment outside of the IDZ, no chronic effects are permitted. The presence or absence of chronic effects for aquatic life is often defined by the use of ambient WQG, which provide a conservative assessment of the potential for chronic effects as described above. The objective of this assessment was to evaluate the potential for PAHs to be introduced into the water column at concentrations that may result in direct toxicity in the receiving environment (i.e., outside the IDZ/work zone). This assessment does not consider the point of discharge (i.e., the point of dredging), as this will be an active work area that will be consistently disturbed. Moreover, mitigation measures are expected to be developed for the project to minimize the off-site transport of contaminated sediments, in particular when dredging of the most contaminated sediments is being undertaken. 3.0 METHODS 3.1 Approach The assessment of potential for water quality effects was approached step-wise: 1) Individual PAH concentrations in water were predicted (Section 3.2). 2) Predicted water concentrations were screened against ambient WQG (Section 3.3) assuming the total concentration represents the whole fraction of PAH that may be bioavailable. 3) Where ambient WQG were exceeded: a. The safety factor incorporated into the WQG derivation was reviewed and where the predicted water concentration was within the safety factor (Section 3.3), the exceedance was not considered ecologically relevant. b. The potential for partitioning of PAH between particulate and dissolved (bioavailable) fractions was considered (Section 3.4). Where the bioavailable fraction was less than the WQG, the PAH total concentration was not considered ecologically relevant. 2/9

3 3.2 Water Quality Predictions The potential water concentrations of individual PAHs resulting from the suspension of sediments during dredging and disposal at sea activities were estimated as the product of the concentration of PAHs in sediments and an expected total suspended solids (TSS) concentration in water, as follows: 1,000,000 Where: Conc PAH in water is the concentration of PAH in water in mg/l Conc PAH in sediment Conc TSS in water is the concentration of PAH in sediment in mg/kg is the concentration of total suspended solids in water in mg/l Individual PAH in water concentrations were calculated based on: Concentrations of individual PAHs in 450 sediment samples from the LNG Canada dredge pocket ranging in total PAH (as Σ16PAH) concentrations from non-detectable to 207 mg/kg dw (Golder 2014a). A range of TSS concentrations (i.e., 5, 10, 25, 50, 100, and 200 mg/l) that may be encountered during dredging at a potential IDZ of 300 m based on plume dilution modelling by ASL (2015). 3.3 Screening Against Ambient Water Quality Guidelines The predicted concentrations were conservatively screened against ambient WQG for the protection of aquatic life, selected based on the following hierarchy of preference: Marine WQG from BCMOE (1993); Freshwater WQG from BCMOE (1993); and Freshwater WQG from CCME (1999a). Ambient water quality guidelines (WQG) for the protection of aquatic life are available from BC MoE (2006a, b) and CCME (1999, with updates to 2014): BC WQG: The provincial guidelines provide long-term average and maximum approved WQGs. The short-term maximum is intended to protect against severe effects such as lethality, and the long-term average is intended to protect against sublethal or chronic effects. The long-term average WQGs are generally intended to be applied to mean concentrations of five samples collected over a 30-day period of time (Meays 2010). CCME: The Canadian water quality guidelines (CWQGs) are generally derived to protect sensitive species from chronic effects. More recently-derived CWQG consist of separate values for long-term (an indefinite period of time with guideline derivation relying on chronic toxicity tests [e.g., >7 d exposure]) and short-term (defined as 24 to 96 h, derived using severe-effects [e.g., lethality] data) exposure (e.g., CCME 2014). Ambient WQG are typically derived from: conservative endpoints (e.g., lowest observed effects concentrations or LOECs); the most sensitive species for which toxicity test data are available; and safety factors (often 10 times) are applied to add conservatism. The CCME and BC freshwater WQGs are generally intended to be applied to total concentrations in unfiltered waters. 3/9

4 The potential for phototoxic effects (BC MoE provides separate guidelines for chronic and phototoxic effects) was not considered because the scenario being evaluated is unlikely to result in PAH phototoxicity. By nature the water will contain turbidity which will reduce UV penetration. Moreover, the work is expected to occur during the winter when there is more cloud cover and the sun is low in the horizon, further reducing the potential for UV penetration. 3.4 Consideration of Partitioning Between Particulate and Bioavailable Fractions Further conservatism in this assessment results from assuming that the total concentration represents the whole fraction of PAH that may be bioavailable. A significant proportion of PAHs in the proposed dredge pocket area is understood to be related to historical releases of pencil pitch from the Alcan smelter during unloading operations or through stormwater discharge, as described in Simpson et al. (1998). The significance of the pencil-pitch source is that it is associated with soot, or black, carbon which has a greater affinity for binding PAH than doe naturally-derived organic carbon. PAHs associated with black carbon, therefore, tend to have lower bioavailability (see for example Rust et al. [2004]). Based on the sediment-water equilibrium partitioning coefficients (K SW ) derived in Golder (2014b), the bioavailable fraction would be four to five orders of magnitude lower than the predicted total concentration in water. 4.0 RESULTS AND DISCUSSION 4.1 Screening Table 1 summarizes maximum predicted concentrations based on ranges of total PAH concentrations in sediment and different TSS concentrations. For TSS concentrations of up to 200 mg/l, benzo(a)pyrene, chrysene, fluoranthene and phenanthrene were the only individual PAHs predicted to exceed ambient WQG. 4.2 Potential for Effects at the Dredging Location Plume Modelling Approach ASL (2015) employed an ASL-COCIRM-SED circulation model to predict sediment transport and fate of released sediment during active dredging activities at the loading site. A number of scenarios were considered in the model with various assumptions regarding particle size and density, dredging methods and dredge cycle time. Generally, the more contaminated material is likely to be removed via a backhoe dredge (BHD) and material that is DAS-eligible via a cutter suction dredge (CSD). ASL (2015) presented modelling results that relied on ambient oceanographic conditions and were adjusted to account for the presence of a silt curtain (i.e., the expected TSS load in the water column at the point of suspension during dredging was reduced by 50%). Without a silt curtain present, the concentration of TSS is thus expected to be higher but the spread of the plume is expected to be approximately the same (D. Fissel, ASL, pers. comm. 2015). ASL (2015) also specifically evaluated the potential difference in plume behaviour with and without a silt curtain present for one model run and confirmed that on average the plume geometry did not change. The maximum predicted TSS concentration also did not change. Thus, it is possible to use the results for the greater number of modelling runs to assess the potential for water quality effects from TSS, taking into account the potential for the TSS concentration may be under predicted for a scenarios without a silt curtain in place. ASL (2015) used a preliminary design target of 25 mg/l TSS above background at the edge of an initial dilution zone (IDZ) of 300 m as a screening target for the modelling. The TSS concentration of 25 mg/l was based on the CCME (1999b) maximum for short-term exposure. Additional screening against the CCME (1999b) guideline of 5 mg/l for long-term exposure was also conducted. 4/9

5 Predicted TSS and PAH Concentrations Dredging of material with the highest Σ16PAH (i.e., >100 mg/kg) concentrations observed in the LNGC dredge pocket (Area B as delineated by ASL [2015]; adjacent to proposed Berth 2) was assumed to be conducted with a BHD which results higher TSS concentrations in the upper portion of the water column than at the seabed. Maximum derived TSS concentrations were predicted to be <5 mg/l at the 300 m IDZ near the surface and <1 mg/l at depth (ASL 2015). At a TSS concentration of 25 mg/l, the predicted seawater concentrations were in the order of eight times the WQG for benzo(a)pyrene and 1.5 times the WQG for chrysene (Table 1). Exceedances of other individual PAHs were not predicted. Along the face of the former Eurocan Wharf (location of proposed Berth 1), a proportion of the area has Σ16PAH concentrations in the range of 30 to 100 mg/kg. The source of these PAHs has been attributed to creosote (Golder 2014c). Assuming that this material will be excavated using a BHD ASL (2015) predicted that higher TSS concentrations would occur in the upper water column than near the seabed, and that the maximum derived TSS at 300 m would be on the order of 5 mg/l. At this TSS concentration, benzo(a)pyrene is predicted to exceed the WQG by five times (Table 1). Exceedances of other individual PAHs were not predicted. During dredging of sediment would be of suitable quality for disposal at sea (DAS) maximum instantaneous TSS concentrations were predicted to be up to 25 mg/l and to occur episodically for a few to several days. Dredging of this material was assumed to occur with a CSD the predicted TSS concentrations were higher near the seabed than in the upper water column. For sediment Σ16PAH concentrations of 30 mg/kg and less, the maximum predicted benzo(a)pyrene concentration would be up to approximately eight times the WQG (Table 1). Exceedances of other individual PAHs were not predicted. Potential for Effects The WQG for benzo(a)pyrene is derived from the lowest observed chronic level of the PAH of 0.10 µg/l, which reduced the average hatching success of sand sole (Psettichthys melanostichus) by 29% compared to control; a ten-fold safety factor was applied to this concentration. The exceedances observed in the predicted concentration of benzo(a)pyrene for all three scenarios discussed above were within the ten-fold safety factor. Moreover, the bioavailable fraction is predicted to be several orders of magnitude lower than the WQG and thus, effects in the receiving environment would not be expected during dredging of the LNGC dredge pocket. The working WQG for chrysene is derived from the lowest observed chronic level of the PAH of 1.0 µg/l, which increased the incidence of molts of pink shrimp (Penaeus duorarum) after 28 days of exposure; a ten-fold safety factor was applied to this concentration. The exceedances observed in the predicted concentration of chrysene for all three scenarios discussed above were within the ten-fold safety factor. Moreover, the bioavailable fraction is predicted to be several orders of magnitude lower than the WQG. Thus, effects in the receiving environment would not be expected during dredging of the LNGC dredge pocket. 5/9

6 5.0 UNCERTAINTY The water quality assessment conducted here was necessarily a predictive exercise with the objective of identifying whether or not the sediment plume from the proposed dredging at the LNG Canada Export Facility will result in adverse effects to the receiving environment. Assessing impact before the existence of a sediment plume requires the use of various predictive tools such as sediment plume modeling. While these tools are useful and provide a reasonable prediction of likely circumstances, it is important to identify the major uncertainties associated with a predictive assessment and to consider the implications of these uncertainties on predictions made. The primary uncertainties associated with this assessment are as follows: The sediment plume will be as predicted by the modelling conducted by ASL (2015). The modelling was based on assumptions regarding dredging methods. If the dredging methods ultimately selected for execution of the dredging project change, the present plume modelling results may over or underestimate the TSS concentrations in and geometry of the sediment plume, and thus the associated water quality predictions may also over or underestimate the potential for water-borne exposure to harmful concentrations of PAHs. The potential for cumulative effects if dredging occurs at the LNG Canada site simultaneously with dredging to support the adjacent Rio Tinto Alcan Port Development Project. If there is potential for sediment plumes from simultaneous dredging to overlap, the present assessment may underestimate the potential for water-borne exposure to harmful concentrations of PAHs. However, project planning is being undertaken to help minimize the potential for spatial overlap of sediment plumes from the two projects. Interaction of mixtures of PAHs will not result in effects greater than those estimated through the use of WQG. While parameters of concern were assessed individually, the potentially bioavailable fraction of the individual PAHs results in predicted water concentrations were orders of magnitude lower than applicable WQGs. Thus, there is a low likelihood of contaminant interactions. 6.0 SUMMARY This technical memorandum presents an evaluation of the potential for PAHs to be present in the water column as a result of dredging and to subsequently cause toxicity. Water concentrations of PAHs were predicted by multiplying the mass of PAHs in sediments to the total suspended solids (TSS) concentration in water at the edge of a pre-defined IDZ. The predicted PAH concentrations were then conservatively screened against ambient water quality guidelines for protection against chronic, sub-lethal effects. Although exceedances of the WQG for benzo(a)pyrene and chrysene were predicted to occur under some circumstances, the exceedances were within the ten-fold safety factor of the WQG and the bioavailable fraction is predicted to be several orders of magnitude lower than the WQG. Thus, there is low potential for adverse effects in the receiving environment. Monitoring during project activities will be conducted to verify TSS and PAH concentrations in the water column. 6/9

7 7.0 STATEMENT OF LIMITATIONS This technical memorandum was prepared for the exclusive use of LNG Canada Development Inc. (the Client). Any use that a third party may make of this report, or any reliance on or decisions made based on it, is the responsibility of the third parties. We disclaim responsibility for consequential financial effects on transactions or property values, or requirements for follow-up actions and costs. In evaluating the project, we have relied in good faith on information provided by others as noted. We assume that the information provided is factual and accurate. We accept no responsibility for any deficiency, mis-statement or inaccuracy contained in this report as a result of omissions, misinterpretations or fraudulent acts of persons providing data, including derived predictions from those data, persons interviewed or contacted. The services performed as described in this report were conducted in a manner consistent with the level of care and skill normally exercised by other members of the engineering and science professions currently practising under similar conditions, subject to the time limits and financial and physical constraints applicable to the services. The content of this report is based on information collected during our investigation, our present understanding of site conditions, the assumptions stated in this report, and our professional judgement in light of such information at the time of this report. This report provides a professional opinion and, therefore, no warranty is expressed, implied, or made as to the conclusions, advice and recommendations offered in this report. This report does not provide a legal opinion regarding compliance with applicable laws. 8.0 CLOSURE We trust that this technical memorandum provides sufficient information for your present needs. If you have any questions, please contact the undersigned at , GOLDER ASSOCIATES LTD. Barbara Wernick, M.Sc., R.P.Bio. Principal, Senior Environmental Scientist Adrian debruyn, Ph.D., R.P.Bio. Associate, Senior Environmental Scientist BGW/AMD/ch o:\final\2013\1447\ \ tm-rev0-3010\ tm-rev load site wq assess 27feb_15.docx 7/9

8 9.0 REFERENCES ASL (ASL Environmental Sciences Inc.) Modeling of sediment releases from dredging activities at the LNG Canada facility in Kitimat Arm. Prepared for Golder Associates Ltd. ASL File: PR-880. BC MoE (British Columbia Ministry of Environment) Ambient water quality criteria for polycyclic aromatic hydrocarbons (PAHs): overview report. Available at: CCME (Canadian Council of Ministers of the Environment). 1999a. Canadian water quality guidelines for the protection of aquatic life: polycyclic aromatic hydrocarbons (PAHs). Available at: CCME. 1999b. Canadian water quality guidelines for the protection of aquatic life: total particulate matter. Golder (Golder Associates Ltd.). 2014a. Excel spreadsheet with sediment chemistry data. Submitted to LNG Canada Development Inc. Document No.: Rev LNGC_Load_SiteEC_14Nov_14.xlsx. Golder. 2014b. Technical memorandum. Desktop bioaccumulation assessment for proposed disposal at sea of dredged material from the proposed LNG Canada LNG export terminal. Reference No TM-Rev December 19, Golder 2014c. LNGC dredge pocket: discussion of results of sediment investigations. LNG Canada Liquefied Natural Gas facility, Kitimat, BC, Canada. Report Number R-Rev Meays C Derivation of water quality guidelines to protect aquatic life in British Columbia (Update of Singleton et al ). Science Information Branch, Ministry of Environment. Rust AJ, Burness RM, McElroy AE, Cantwell MG, Brownawell BJ Role of source matrix in the bioavailability of polycyclic aromatic hydrocarbons to deposit-feeding benthic invertebrates. Environ Tox Chem 23(11): Simpson CH, Harrington C, Cullen W Polycyclic aromatic hydrocarbon contamination in marine sediments near Kitimat, British Columbia. Environ Sci Technol 32: /9

9 Table 1: Summary of Maximum Predicted PAH Concentrations in Water for a Given Range of Total PAH Concentrations in Sediment and TSS Concentrations Water concentration (mg/l) Total PAH in TSS sediment (mg/l) Acenaphthenthylencene anthracene pyrene fluoranthene perylene fluoranthene anthracene Acenaph- Anthra- Benzo(a) Benzo(a) Benzo(b) Benzo(g,h,i) Benzo(k) Dibenzo(a,h) Fluoranthene (mg/kg) Chrysene Fluorene Indeno (1,2,3-c,d) pyrene Naphthalene Phenanthrene Pyrene WQG 6.00E-03 na 4.00E-03 na 1.00E-05 na na na 1.00E-04 na 4.00E E-02 na 1.00E E-04 na E E E E E E E E E E E E E E E E to E E E E E E E E E E E E E E E E-06 5 to E E E E E E E E E E E E E E E E to E E E E E E E E E E E E E E E E to E E E E E E E E E E E E E E E E-05 > E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E to E E E E E E E E E E E E E E E E-06 5 to E E E E E E E E E E E E E E E E to E E E E E E E E E E E E E E E E to E E E E E E E E E E E E E E E E-04 > E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E to E E E E E E E E E E E E E E E E-05 5 to E E E E E E E E E E E E E E E E to E E E E E E E E E E E E E E E E to E E E E E E E E E E E E E E E E-04 > E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E to E E E E E E E E E E E E E E E E-05 5 to E E E E E E E E E E E E E E E E to E E E E E E E E E E E E E E E E to E E E E E E E E E E E E E E E E-04 > E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E to E E E E E E E E E E E E E E E E-05 5 to E E E E E E E E E E E E E E E E to E E E E E E E E E E E E E E E E to E E E E E E E E E E E E E E E E-03 > E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E to E E E E E E E E E E E E E E E E to E E E E E E E E E E E E E E E E to E E E E E E E E E E E E E E E E to E E E E E E E E E E E E E E E E-03 > E E E E E E E E E E E E E E E E-03 Notes: na not available; TSS total suspended solids; WQG water quality guideline 9/9