When is it appropriate to use the Gasoline Range Organics (GRO) and Diesel Range Organics (DRO) methods?
A. The GRO and DRO methods are non-specific methods identified for use in evaluating petroleum products, solvents or aesthetic groundwater impacts arising from stained and/or odorous contaminated soils where the typical petroleum indicator parameters (e.g., BTEX, trimethylbenzenes (TMBs) and PNA’s) are absent. Target MDL criteria or aesthetic criteria are acceptable for demonstrating cleanup of aesthetically impacted soils. The GRO Method is recommended for evaluating various petroleum solvents, such as Stoddard solvents, which do not usually contain measurable quantities of BTEX, TMB and PNA compounds. Refer to Attachment No. 12 Section 7.2.5 of the Guidance Document for a full explanation on this non-specific method. Any free product that is present must be removed in accordance with Section 21307(c) of Part 213. The application of these methods is not associated with any risk-based evaluation but is available as a tool to address aesthetic situations.
Related Questions
- Could you provide examples of "significant" and "minor" deficiencies and suggest appropriate methods for reporting them in the Institutional Semiannual and Annual Reports?
- Since the GRO and DRO cleanup criteria are not risk-based, what is the appropriate application of this criteria in the RBCA process?
- What are the appropriate methods for guiding curved chain?
