Site Remediation Program Monitored Natural Attenuation ...

1 New jersey Department of Environmental Protection site Remediation Program Monitored Natural Attenuation technical guidance DATE. 3/1/2012. Version: March 1, 2012. TABLE OF CONTENTS. technical guidance .. 1. 1 INTENDED USE OF guidance DOCUMENT .. 1. 2 PURPOSE .. 2. 3 DOCUMENT OVERVIEW .. 2. 4 APPLICABILITY OF Monitored Natural Attenuation .. 3. Monitored Natural Attenuation Role in Remedial 3. Source Control .. 4. technical 5. Conditions That Generally Preclude Monitored Natural Attenuation as a Sole Ground Water 5. 5 site CHARACTERIZATION .. 6. Conceptual site Model for Monitored Natural Attenuation .. 6. Aquifer Characteristics .. 7. Contaminant Spatial and Temporal Distribution .. 7. Evaluation of Seasonal Trends .. 8. Defining Plume Geometry.

2 9. Identification of Hydraulic Perturbations .. 11. 6 LINES OF EVIDENCE .. 12. Primary Line of Evidence - Evaluation of Contaminant Plume Characteristics .. 12. Plume Behavior .. 13. Contaminant Trends .. 15. Spatial Analysis .. 15. Graphical Analysis .. 17. Statistical 18. Mass Flux and Mass Discharge .. 22. Secondary Line of Evidence - Geochemical Conditions .. 22. Organics .. 23. Terminal Electron Acceptors (TEA) .. 23. Degradation By-products and other Indicators .. 25. Metals & Radionuclides .. 27. Tertiary Line of Evidence - Microbiological and Isotopic Studies .. 30. Microbiological Tools .. 30. Isotopic Studies .. 31. Protective Ground Water Remedies with Non-Decreasing Levels of Ground Water Contamination .. 31. 7 REMEDIAL ACTION PERMIT FOR GROUND WATER WITH LONG TERM MONITORING.

3 32. Long Term Monitoring Program .. 32. Analytical Parameters .. 35. Monitoring Well Network .. 35. Performance Evaluation of the Data .. 35. 8 REPORTING .. 37. 9 REFERENCES .. 38. Version: March 1, 2012. FIGURES. Figure 1: Generalized Monitoring Well Network Figure 2: Generalized Monitoring Well Network Figure 3: Plume Behaviors Figure 4: Comparison of Projected Versus Actual Plume Migration Figure 5: Contaminant Concentration Plots Figure 6: Conceptualization of TEA Zones in Ground Water Contamination Plume TABLES. Table 1: Possible Causes of Seasonal Conditions Observed at Source Zone Water Table Monitoring Wells Table 2: Lines of Evidence Table 3: Geochemical Parameters Important to Anaerobic Dedegradation Table 4: Recommended Monitoring Well Sampling Frequency APPENDICES.

4 Appendix A: Degradation/Stabilization Processes Appendix B: Compound Specific Isotope Analysis Appendix C: Contaminant Mass Example Calculations Appendix D: Aquifer Characteristics Appendix E: Trend Analysis and Statistical Tests Appendix F: Selected Reference Summaries Appendix G: Glossary Appendix H: Acronyms Version: March 1, 2012. Monitored Natural Attenuation . technical guidance . 1 INTENDED USE OF guidance DOCUMENT. This technical guidance is designed to help the person responsible for conducting Remediation to comply with the State of New jersey Department of Environmental Protection (NJDEP or Department) requirements established by the technical Requirements for site Remediation ( technical Rules), 7:26E. This guidance will be used by many different people involved in the Remediation of a contaminated site , including: Licensed site Remediation Professionals (LSRPs), Non-LSRP environmental consultants and other environmental professionals.

5 Therefore, the generic term investigator will be used to refer to any person that uses this guidance to remediate a contaminated site on behalf of a remediating party, including the remediating party itself. The procedures for a person to vary from the technical requirements in regulation are outlined in the technical Rules at 7 Variances from a technical requirement or departure from guidance must be documented and adequately supported with data or other information. In applying technical guidance , the Department recognizes that professional judgment may result in a range of interpretations on the application of the guidance to site conditions. This guidance supersedes all previous Department guidance issued on this topic and was prepared with stakeholder input.

6 The committee consists of: Matthew Turner, Co-chair, NJDEP. Steve Posten, Co-chair, AMEC Environment and Infrastructure, Inc. Renee Bancroft, NJDEP. David Bausmith, Whitman Companies, Inc. Ann Charles, NJDEP. Julian Davies, Sovereign Consulting, Inc. Rich Lake, Environmental Resolutions, Inc. George Nicholas, NJDEP. Rao, EG&R Environmental Services The use of any trade names, products or materials in this manual does not constitute an endorsement by the NJDEP. The Web links and Web addresses in the technical guidance are sites not maintained by the NJDEP or the State of New jersey . The NJDEP makes no special endorsement for the content of these links, their sites or the views expressed by the sites' publishers. Version: March 1, 2012. Page 1 of 46.

7 2 PURPOSE. This guidance is being developed due to changes to the way contaminated sites are remediated in New jersey pursuant to the site Remediation Reform Act (SRRA) 58:10C-1 et seq. The Department rules under which this document will be implemented are the Administrative Requirements for the Remediation of Contaminated Sites (ARRCS) Rules, 7:26C, the Industrial site Recovery Act (ISRA) Rules, 7:26B, the Underground Storage of Hazardous Substances (UST) Rules, 7:14B, and the technical Rules. 7:26E. This technical guidance document was developed to provide detailed technical information on the use of Monitored Natural Attenuation (MNA) as a remedial action for a contaminated ground water site in New jersey . The term MNA refers to the reliance on Natural Attenuation processes to achieve the applicable ground water Remediation standard.

8 Natural Attenuation processes include a variety of physical, chemical, or biological processes that, under favorable conditions, act without human intervention to reduce the mass, toxicity, mobility, volume, or concentration of contaminants in ground water. These processes include biodegradation, dispersion, dilution, sorption, volatilization, and chemical or biological stabilization, transformation, or destruction of contaminants. At sites with organic compound contamination, MNA is most effective where the Natural processes permanently degrade or destroy contaminants. For inorganics, MNA is most effective where immobilization or radioactive decay is demonstrated to be occurring. MNA is most appropriate when used in conjunction with other remedial measures or as a follow up to an active remedial action.

9 Approaches to evaluate and implement MNA as a remedial strategy for ground water are outlined in this technical guidance document. The objective of the evaluation process is to demonstrate that MNA will result in a reduction in the concentration of ground water contaminants until they meet the Remediation Standards at 7:26D. This technical guidance document does not address enhanced MNA. Other agencies such as the Interstate Technology and Regulatory Council (ITRC) have developed guidance documents to address enhanced MNA (ITRC, 2008). The focus of this document is on the MNA of ground water, and it does not address Natural Attenuation in soil. The Department has requirements ( 7:26E) for the evaluation of receptors, light non- aqueous phase liquid (LNAPL) and immediate environmental concerns (IECs).

10 Please consult Department rules and guidance on these issues prior to evaluating the applicability of MNA for a given site . 3 DOCUMENT OVERVIEW. The scope of this document is to address MNA of ground water for organic compounds, particularly petroleum hydrocarbons and chlorinated solvents, inorganics and radionuclides. Numerous references are listed for additional information, and excerpts from selected references are provided in the Appendices. Version: March 1, 2012. Page 2 of 46. Decisions to utilize MNA are supported by site -specific data and analysis. This guidance involves the use of a conceptual site model (CSM) based on a site characterization that focuses on MNA as a remedy. An understanding of the distribution of the ground water contaminants and the site hydrogeological data are critical elements of the site characterization.