Merging technologies will change over Hexavalent Chromium in soil to Trivalent Chromium, effectively stopping Hexavalent Chromium from becoming dangerously airborne or becoming even more deadly by migrating into the water table.
There are three valences of Chromium: 1) Chromium—safe to humans, 2) Trivalent Chromium—safe and an essential element in humans and 3) Hexavalent Chromium—highly carcinogenic to humans. Erin Brockovich's fame and fortune came from Erin's dogged and tenacious quest to defeat Pacific Gas and Electric Company (PG&E) in the poisoning of the residents of Hinkley, CA by its use of Hexavalent Chromium in its Hinkley facility. PG&E stored Hexavalent Chromium in their cooling towers as a coolant and to prevent rust from forming in its natural gas compressors. Then, they discharged and stored the residual Hexavalent Chromium liquid in unlined ponds contaminating soil, subsequently, the Hexavalent Chromium percolated into the water table, which caused life suffering-cancerous diseases to the residents of Hinkley, that would eventually lead to death. Before Erin came along, PG&E was buying up homes in Hinkley and paying medical bills for all the sick residents. This was the cheapest way out for PG&E, relieving them of all liabilities. Ultimately, PG&E, a $21 billion company, settled two Hexavalent Chromium lawsuits in Hinkley, CA for $333 million and Kettleman Hills, CA for $335 million.
Regulating Hexavalent Chromium
Hexavalenc Chromium has caused a mired amount of suffering and deadly diseases that range from asthma, liver disease, lung cancer, stomach cancer, skin cancer, cardiovascular disease, as well as many other deadly cancerous effects to external and internal human organs. Hexavalent Chromium cancer clusters can be isolated and identified to specific areas of our environment, such as former Chromium manufacturing sites and those dumping sites, as well as in coal ash and their unlined dumping sites.
Although the EPA has no standard that regulates the cleanup of Hexavalent Chromium, it does regulate the permissible limits for Hexavalent Chromium in soil and Water. The EPA, in order to ensure safe drinking water, has an enforceable drinking water standard of 0.1 milligrams per liter (mg/L) or 100 parts per billion (ppb) for total chromium, which includes Hexavalent chromium and Trivalent Chromium. In fact, California has set its regulatory limit of 10 ppb for Hexchrome, which went into effect July 1. A national set by EPA won't be far behind.2 The EPAs permissible limit for Hexavalent Chromium in soil would have to be detected by a Toxicity Characteristic Leaching Procedure (TCLP). When tested by TCLP the hazardous contaminant in the soil must be under 5pg/L.
EPA's Exposure Limits
Hexavalent Chromium’s allowable permissible exposure limit (PEL) in an eight-hour work period is a Total Weight Average (TWA) of 5 micrograms per cubic meter (pg/m3), meaning that over the course of any eight-hour work shift, the average exposure to the worker cannot exceed 5pg/m3. The Action Level the level of exposure to a harmful substance or other hazard present in a work environment or situation at which an employer must take the required precautions to protect the workers is normally one half of the permissible exposure limit. For Hexavalent Chromium the action level is set at 2.5 pg/m3, calculated as an eight-hour TWA. Exposures above the Action Level trigger specific requirements, and exposures above the PEL trigger additional requirements. The substantive provisions of Hexavalent Chromium standard are described below.