The Use of Ecological Risk Assessment for Regional Management of Aquatic Impacts. A Case Study

Transcription

1 The Use of Ecological Risk Assessment for Regional Management of Aquatic Impacts A Case Study

2 Background Information Development of area first started in 1961 Petro-Canada acquired inactive properties along the Beatton River Historical on-site contamination, possibly migrating off-site

3 Study Area

4 Typical Lease on the Beatton River

5 Assessment Objectives Assess the impact, if any, the surrounding contaminated sites have had on the Beatton River Water chemistry analysis Sediment chemistry analysis Benthic invertebrate community structure

6 Study Design Design of the study based on ecological risk assessment conducted for Pembina following the Pine River spill Pine River Study clearly showed impacts to, and recovery of, the ecosystem as well as influence of other sources, unrelated to the spill

7 Methods Water Quality Concentrations of hydrocarbons in surface water at selected sites (grab samples and semipermeable membrane devices or SPMDs) Sediment Monitoring Concentration of hydrocarbons in sediment core samples collected at selected sites Benthic Invertebrate Community Diversity Measured diversity at selected sites using Hess Sampler

8 Modified Shelby sediment sampling tubes

9 Hess sampling unit

10 Methods Continued Semi-permeable Membrane Devices (SPMDs) Lipid-filled membranes mimic fatty tissues Allows for detection of ultra-trace concentrations of organic compounds Time integrated sampling provides a cumulative concentration of PAHs over a 30-day period

11 SPMD in deployment canister

12 SPMD canister mounted on concrete pad before being deployed in the Beatton River

13 SMPD canisters and concrete pads are fully submersed in the Beatton River

14 Analytical Program Water: Benzene, toluene, ethylbenzene and xylenes (BTEX) Light and Heavy Extractable Petroleum Hydrocarbons (LEPHs & HEPHs), Polycyclic Aromatic Hydrocarbons (PAHs) Dissolved Metals, Routine Parameters SPMDs: PAHs and Alkylated PAHs Sediments: PAHs and Alkylated PAHs Organic Content

15 Regulatory Framework CCME Water: 11 PAH Compounds Sediment: 13 PAH Compounds BC CSR Water: 12 PAH Compounds Sediment: 13 PAH Compounds BC AWQG Water: 9 PAH Compounds Sediment: 9 PAH Compounds

16 CCME PAHs vs. Alkylated PAHs in Petroleum Products 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Condensate Diesel Oil CCME PAHs Alkylated PAHs

17 Toxic Equivalency Factors of Alkylated PAHs Compound Naphthalene C1-Naphthalene C2-Naphthalene C3-Naphthalene C4-Naphthalene Benzo(a)pyrene TEF

18 Sampling Locations

19 Results Water Quality 36 water samples collected at 16 sites along the Beatton River and its tributaries Concentrations of hydrocarbons were non-detectable or below applicable criteria at all sites Aluminum and iron concentrations exceeded applicable criteria at all sites No other parameters exceeded applicable criteria

20 Results SPMDs Concentration (ng/l) 1,000, ,000 10,000 1, Naphthalene C1-naphthalene C2-naphthalene Most Sensitive Toxicity Endpoint for Naphthalene SP 0.1 SP 0.9 SP 1.0 SP 2.0 SP 5.0 SP 6.0 Sample Location Naphthalenes present at very low concentrations in Beatton River. Orders of magnitude below documented toxicity and probable effects levels.

21 Results Sediment CCME PAHs Alkylated PAHs PAHs ubiquitous in Upper Beatton watershed Some PAHs above CCME and/or BC CSR criteria Great variations in PAHs concentrations R0.1 R0.9 Apassin Creek 2.0 Apassin Creek 1.0 R1.0 R2.0 R3.0 R4.0 Julienne Creek R5.0 Unnamed Tributary #2 Unnamed Tributary #1 R6.0 Concentration (ppm)

22 Results Benthic Invertebrates 6 Fairly Poor 5.5 Fair Family Biotic Index Good Very Good 3.5 Excellent 3 B0.9 BAC1.0 B1.0 B2.0 B3.0 B4.0 BJC B5.0 B6.0

23 Conclusions Water No hydrocarbons were found above criteria High levels of iron and aluminum likely a local phenomena hydrocarbon concentrations found in the SPMDs were several orders of magnitude below toxicity levels

24 Conclusions Continued Sediment Some PAHs found above criteria Possible widespread historical impact and/or natural causes Benthic Invertebrates Overall poor diversity and species richness Relationship between benthic community and sediment quality under investigation

25 Summary Sediments appear to be impacted, but PAHs are likely not transferable to fish Water quality shows no impact from hydrocarbons

26 On-going and future work Focus on areas were sediments showed hydrocarbon impacts Establish sediment toxicity to benthic invertebrates as per BC CSR Expand the program to additional tributaries that might contribute hydrocarbon loading to the Beatton River

27 Aknowledgments Petro Canada Tim Taylor Mike Morden Pembina Pipeline Corporation Shawna Mattison Alpine Environmental Roy Crowther