1. Ecological Risk Assessment (ERA) Program Case Study and Program Updates
Michael Smith and Greg Zychowski
TCEQ Remediation Division
Texas Commission on Environmental Quality
Environmental Trade Fair and Conference 2019

2. ERA Program Overview and Updates

3. Ecological Risk Assessment in Texas
Ecological Risk Assessment (ERA) – a process that evaluates adverse ecological effects as a result of exposure to one or more environmental stressors.
ERA program in Texas was formalized under the TRRP rule, 30 TAC 350.
ERAs often form part of the evaluation for various Remediation programs.

4. Ecological Risk Assessment in Texas (cont’d)
Three-tiered system
Tier 1 – Exclusion criteria checklist
Tier 2 – Screening level ERA (SLERA)
Tier 3 – Site-specific ERA (SSERA)
Related submittals
Expedited stream evaluations
Reasoned justifications

5. Responsibilities of the ERA Program
Provide technical support to project managers (PMs) in the review of ERAs.
Review ecological aspects of affected property assessment reports (APARs) and other documents as necessary (e.g., sampling plans).
Coordinate with Natural Resource Trustee agencies on ERA reviews.

6. Responsibilities of the ERA Program (cont’d)
Participate in calls and meetings with site representatives, consultants, and PMs.
Develop and maintain guidance documents and ecological screening benchmarks.
Oversee continued development and maintenance of the Protective Concentration Level (PCL) Database.
Provide training to staff and inform the public of new developments and expectations.

7. Recent Developments RG-263 (revised August 2018)
Conducting Ecological Risk Assessment at Remediation Sites in Texas
RG-263b (published August 2018)
Supporting Documentation for the TCEQ’s Ecological Benchmark Tables
Benchmark updates (RG-263b tables)
Work is ongoing.

8. Recent Developments (cont’d)
RG-263c (published August 2018)
Case Study for the TCEQ’s Ecological Risk Assessment Process
PCL Database Updates – new or in progress
Species added
Chemicals of concern (COCs) added
Functionality improved

9. Case Study for the TCEQ’s Ecological Risk Assessment Process

10. TCEQ Ecological Risk Program: Case Study (RG-263c)
Why?
Potential for ERA with any APAR
Promote consistency
Who?
Guidance for project managers, environmental professionals and ecological risk assessors
What?
Step-by-step approach

11. TCEQ Ecological Risk Program: Case Study Overview
Presents a fictional site and data to illustrate circumstances encountered by TCEQ in the past
Covers Tier 1 Exclusion Criteria Checklist, Tier 2 screening level ecological risk assessment (SLERA) and Ecological Services Analysis (ESA)
Demonstrates level of detail expected by the TCEQ ERA Program

12. Case Study – Apollo Wood Treating Company (AWTC) Site
Former wood treatment facility from 1950 to 2004
15-acre tract
Lumber treated with creosote and PCP
In 2006 former wood treatment area (soil) partially excavated
Oil field support business on eastern 5 acres
Perennial creek and wetland offsite

14. Tier 1 Exclusion Criteria Checklist
Purpose
Conclusions for AWTC:
Eastern 5 acres is disturbed ground, active commercial use and removed from further assessment
10 acre assessment area
Identified open pathways to soil, sediment, surface water and ground water
Move to Tier 2 SLERA to address these issues

15. Tier 2 SLERA Purpose Incorporates PCL Database
Follows 10 Required Elements for Tier 2 ERAs in Texas (30 TAC 350)
Concludes with Risk Management Recommendation

16. 10 Required Elements of Tier 2 SLERA
COC Screening Analysis
Exposure Pathway Analysis
Conceptual Site Model
COC Fate and Transport
Receptor Effect Levels and Exposure Assessment
6. Hazard Quotient Analysis No Observed Adverse Effect Level (NOAEL)
Hazard Quotient Analysis Lowest Observed Adverse Effects Level (LOAEL)

17. 10 Required Elements of Tier 2 SLERA (cont’d)
Uncertainty Analysis
Ecological Protective Concentration Level (PCL) Development
Risk Management Recommendation

18. Tier 2 Sampling Methodology and COCs
Samples collected from:
On-site surface and subsurface soil
Off-site riparian transitional area surface soil
Moon Creek surface water and sediment
Wetland surface water and sediment
COCs include:
Metals – arsenic, cadmium, chromium, copper, lead and zinc
Pentachlorophenol (PCP)
Polycyclic aromatic hydrocarbons (PAHs)
Dioxin/furans

21. Required Element 1 COC Screening Analysis
Comparison of affected property concentrations to ecological benchmarks
Media includes soil, surface water, sediment and groundwater
Screening data includes:
Summary tables comparing maximum detection for each COC to benchmark
Site background considered
Groundwater pathway included use of default dilution factor (Section 7.0-TRRP-24)

22. Required Element 1 COC Screening Analysis (cont’d)

23. Required Element 1 COC Screening Analysis (cont’d)
On-Site Surface Soil and Off-Site Riparian Surface Soil
On-Site Subsurface Soil
Moon Creek Surface Water
Moon Creek Sediment
Groundwater
Wetland Surface Water
Wetland Sediment
Arsenic -- X
Cadmium
Chromium
Copper
Lead
Zinc
Pentachlorophenol
Naphthalene NA
Chrysene
Fluoranthene
Pyrene
TPAHs
TCDD TEQ (Avian)
TCDD TEQ (Mammal)
X – COC RETAINED
(--) COC NOT RETAINED
N/A – Not Applicable for Media

24. Hot Spot Analysis Hot spot analysis conducted based on:
Visual and spatial relationships
Statistical outlier tests
Comparison to Default PCLs for shrew and robin.
RG TRRP-15eco
Soil hot spot determined in area near former treatment for lead, zinc, PCP and TPAHs
Hot spot data will be removed from Tier 2 data set; hot spot soil will be remediated

26. Required Element 2 Exposure Pathway Analysis
Identify communities, feeding guilds and representative species supported on-site
Habitat types from PCL database:
Minor habitat – Terrestrial
Freshwater habitat – Riparian area, Moon Creek and Wetland
Justify removal of species found in database
Evaluate threatened and endangered species
White-faced ibis and timber rattlesnake retained as potentially present
Armadillo used to assess subsurface soil

28. Required Element 3 Conceptual Site Model (CSM)
CSM used to illustrate potential contaminant sources, release mechanisms, transport pathways, exposure media and receptors considered

30. Required Element 4 COC Fate and Transport
Fate and transport profiles found in PCL database
Discussion and citation required for COCs outside PCL database

31. Required Element 5 Effect Levels and Exposure Assessment
Receptor Effects Levels
Toxicity Reference Values (TRVs)
including NOAEL and LOAEL
PCL database used in case study including uptake factors for COCs and exposure factors for receptors
Exposure Assessment
95% Upper Confidence Limit (UCL) developed using ProUCL as exposure point concentrations (EPC)
Find outputs on the ERA Program website

32. Required Element 6 and 7 Hazard Quotient Analysis
Definition
Differences between Element 6 and 7
PCLs from database compared to EPCs

35. Database Output

36. Database Output Example (Detail for white faced ibis)

37. Required Element 8 Uncertainty Analysis
Examples:
Data gaps
Benchmark Screening Values
Media Exposure
Reptiles and Amphibians

38. Required Element 9 Ecological PCL Development
Any EPCs which exceed a PCL were carried forward and summarized
The lower of the wildlife-based PCL and benthic PCL is the final ecological PCL for a COC
Establish Final PCL for the site based on risk evaluation
Carry forward to Risk Management Recommendation

39. Required Element 9 Ecological PCL Development (cont’d)
Analyte
Sediment Wetland EPC (mg/kg)
Final Sediment PCL (mg/kg)
Receptors at Risk
Cadmium
3.34
2.99
Benthics
Copper
131.6
90.3
Zinc
335.1
290
Benthics, spotted sandpiper
TPAHs
27.95
12.2
Benthics, spotted sandpiper, marsh wren, red-winged blackbird

41. Required Element 10 Risk Management Recommendations
Tier 2 Data Summary:
No exceedances of PCLs to terrestrial receptors
NOTE: With exception of hot spot which will be remediated through removal action
No exceedances of PCLs in riparian areas, Moon Creek surface water and sediment or wetland surface water
Exceedances of PCLs in wetland sediments only:
Benthic – cadmium, copper, zinc and TPAH
Wildlife – zinc and TPAH (spotted sandpiper); TPAHs (marsh wren and red-winged blackbird)

42. Required Element 10 Risk Management Recommendations (cont’d)
COC excavation in wetland would result in severe impacts to wildlife receptors
Ecological Services Analysis (ESA) proposed as Risk Management Recommendation to address sediment PCLE zone

43. Ecological Services Analysis (ESA)
What is ESA?
When is it appropriate?
Case study ESA summary:
Alternatives considered:
Monitored Natural Recovery
Complete Removal
Capping
Compensatory Restoration with Natural Recovery
Selected alternative
Compensatory restoration of 7 acres to offset the lost ecological services from PCL exceedances

44. For More Information
Ecological Risk Assessment webpage. Online at /remediation/eco/eco.html
Check periodically for updates in guidance and ecological screening benchmarks.

45. ERA Program Contacts Vickie Reat vickie.reat@tceq.texas.gov
Greg Zychowski
Michael Smith