Background & Facility Information

A steel mill has been operating at 12459-B Arrow Route, Rancho Cucamonga, California since 1956. Gerdau North America acquired this facility from TAMCO Steel in October 2010.  Gerdau recycles steel at this mini mill to produce steel rebar used in construction.

The ferrous steel scrap is recycled and delivered to Gerdau by trucks and rail, and then melted in an Electric Arc Furnace to produce steel billets. These billets are then reheated and processed in a rolling mill where they are made into a wide variety of rebar lengths, sizes and grades. Its daily operations and activities are subject to the South Coast Air Quality Management District (SCAQMD) rules, regulations and permit requirements.

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AB2588 and Rule 1402 Activity

Under AB2588, Gerdau is required to submit a toxics inventory every four years.  In 2011, the reported level of toxic emissions from Gerdau placed it in a ‘high’ priority, and Gerdau was required to submit a detailed Air Toxics Inventory Report and Health Risk Assessment (HRA).  After making multiple revisions to the HRA based on SCAQMD staff comments and comments from the state Office of Environmental Health Hazard Assessment (OEHHA), a final version of the HRA was submitted by Gerdau on January 20, 2015. Subsequently, OEHHA revised its HRA guidance document on March 6, 2015 and SCAQMD updated its Rule 1402 on June 5, 2015 to incorporate the new guidance. Due to these changes, SCAQMD staff recalculated the risks using the new HARP2 software available from the state Air Resources Board. After incorporating these changes, SCAQMD staff approved the final version of the HRA on October 8, 2015.

The final approval of the HRA shows that the residential cancer risks and worker non-cancer risks exceed thresholds in Rule 1402. Gerdau is therefore required to notify the public regarding the results of its HRA, and also must submit a Risk Reduction Plan by May 6, 2016, implement the RRP as quickly as feasible, and no later than three years after submission of the RRP.

The dominant emission sources in 2011 that contributed to health risks from Gerdau are from the Electric Arc Furnace, from emissions that bypass emission controls from the melt shop, from diesel engines used to run portable light towers, and from fugitive dust from unpaved portions of the facility. The key pollutants of concern from Gerdau’s operation are hexavalent chromium, dioxins, diesel exhaust particulates, cadmium, and lead.

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Public Notification Meeting

AB2588 Documents   

Additional Information

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