Document ID: EPA-R10-RCRA-2018-0661-0019
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2022-01-21T05:00Z

Emerald-Kalama Bio solids Delisting
                    Preliminary Information Needs Analysis

Basic Study Questions
 Define Constituents of Concern for delisting risk assessment analysis and for verification parameter identification
 Need to evaluate both constituents already known and identified and the potential for other constituents, considering both historical practices (e.g. GW remediation that may capture spills/releases from past production processes).
 Should consider both input to the anaerobic and aerobic WWTP, as well as the capabilities and destruction/removal efficiency of each WWTP.  Note:  Data pertaining to the aerobic WWTP will be needed for purposes of defining inputs to the aerobic WWTP.
 Delisting decision may be a consideration of production processes (past, current and future), WWTP performance and capabilities, and direct analytical verification.  Direct analytical verification will be necessary, but the particular scope and frequency will likely depend on the analysis of production processes and WWTP performance measures.
 Identification of constituents of concern will likely be an iterative process, starting from an initial suite of constituents of concern for input to the DRAS risk analysis software followed by revisions base on initial modelling results.
 While the delisting is specific to the bio solids waste stream, Emerald-Kalama (EK) will need to present data that gives EPA and Ecology and understanding of both the generating and waste treatment processes sufficient to account for all dangerous waste, dangerous constituents and "other factors" associated with these processes as they relate to characterization of the bio solids waste stream.
 The delisting application will need to provide a written record for the decisions EPA and Ecology will make regarding the following:
 What dangerous waste, dangerous constituents and "other factors" were considered in the delisting analysis;
 What specific decision criteria will apply to whether or not bio solids are exempt from dangerous waste/hazardous waste regulation;
 What verification process will be applied to demonstrating bio solids meet the delisting criteria;
Specific Information Needs
 Comprehensive process flow diagram, indicating all inputs to both the aerobic and anaerobic WWTPs.   The process flow diagram will need to identify all contributions to the aerobic and anaerobic WWTPs.  Inputs may be aggregated by production or remediation processes for purposes of defining constituents of concern and documenting waste stream characterization.
 Paired influent/effluent data for both the anaerobic and aerobic WWTP for purposes of defining or estimating constituent specific and constituent class destruction removal efficiencies.
 EK will need to describe in engineering terms how best to evaluate how input waste streams relate to performance of the two WWTPs and the eventual production of bio solids (e.g., whether inputs to the WWTP are best described by the weighted average properties of the various input waste streams, or if inputs are variable over time.  
 EPA's and Ecology's intent is not to regulate how either WWTP system is designed or operated through the delisting process, but rather to evaluate how inputs and the design and operation relate to identification of and compliance with delisting verification parameters.
 While the EPA and Ecology delisting decisions will need to comprehensively consider all dangerous waste, dangerous constituents and "other factors" that apply or may apply to the candidate bio solids, particular verification parameters for direct analytical verification testing may be a smaller set of constituents that provide an effective measure of meeting delisting performance criteria.   In other words, delisting performance criteria may be a combination of meeting influent criteria, WWTP operating parameters (those that demonstrate that it is operated effectively in a matter representative of performance associated with DRE data upon which the delisting analysis is based) as well as direct analytical verification data.