Surface Impoundment 3 (Google Earth)



The EPA is proposing to grant an amendment to the petition submitted by American Chrome and Chemical (Petitioner) in Corpus Christi, Texas. The amendment will add the disposal scenario of surface impoundment as a management option for the chromic oxide wastes in addition to an off-site Subtitle D landfill. The volume of waste is set at a maximum annual generation of 1,450 cubic yards. 

Comment Letter 

March 24, 2021


Harry Shah


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Re: In the Matter of the Proposed amendment “Hazardous Waste Management System; Identification and Listing of Hazardous Waste” American Chrome and Chemical (Petitioner), in Corpus Christi, Texas [Docket ID Number EPA-R06-RCRA-2020-0379]. 


Dear Mr. Shah:


Environmental Review, Inc. has reviewed the proposed amendment and supporting documentation and has the following comments:


1.      Based on the report prepared by Golder [1]: Section 6.0 page 14: “Impacts to groundwater from the K006 waste stream are unlikely, and groundwater monitoring has not been required for management of the K006 waste stream.” When the waste was disposed in a Subtitle D landfill, the landfill has monitoring wells and leachate collection systems by design.  This document does not appear to have considered whether the proposed on-site surface impoundment will provide adequate protection for the environment. Where applicable, please add an evaluation for that. The on-site surface impoundment does not appear to have leak detection capabilities. Where applicable, please add provisions for that.


2.      Based on Section 3.1.1 of Golder’s Sampling and Analysis Plan[2]“, The purpose of the DRAS model is to determine whether an RCRA listed waste qualifies for delisting under 40 CFR 260.20 and 40 CFR 260.22 and the concentrations are below the target risk level of 1E-05 for carcinogens and a hazard quotient of 1 for non-carcinogens in the adult and child resident scenarios.” Based on the report prepared by Golder [1] Section 7.0 page 15: “the detected limits for arsenic and thallium resulted in a carcinogenic risk level of 1.49E-05 and a non-carcinogenic hazard of 2.35.”  Based on the evaluation provided that showed these two elements failed to be below the target risk level, it does not appear that delisting should occur.


3.      Figures 2 and 3 of Golder [1]: The schematics in Figures 1 and 2 appear to be different. This inconsistency may potentially cause operational discrepancies. Please provide clarification and/or corrections if applicable. Please clarify if the process that is depicted in Figure 2 will result in the same characteristics of the waste streams depicted in Figure 1.


When a response is available, please email them to This email address is being protected from spambots. You need JavaScript enabled to view it..




Sahar Ghanem, PhD.

 Sr. Reviewer (Associate in Kentucky)


Barb Johnson, PE

 Sr. Reviewer (Associate in Minnesota)


Stephen Lee, M.S.

Sr. Reviewer (Associate in Massachusetts)


Environmental Review Workshop 

(Environmental Review, Inc., a 501(c)(3) Nonprofit Public Benefit Organization)

1792 Rogers Avenue 

San Jose, California 95112



[1] Golder Associates Inc (2019). “Petition to Delist Chromic Oxide Solids from Lists of Hazardous Wastes in 40 CFR Part 261 TXD098818339; SWR 31661”. Houston, Texas, USA.


[2] Golder Associates Inc (2019). “Sampling and Analysis PlanK006 Waste Delisting American Chrome and Chemicals, Inc.Corpus Christi, TexasTXD098818339; SWR 31661”. Houston, Texas, USA.