Reference no: EM133274752

Introduction

You work as an Environmental Specialist at XYZ Steel Mill, Inc. located in Longview, TX. Your primary responsibilities include (1) overseeing the company's compliance to all local, state, and federal rules and regulations related to air, water, and wastes and (2) assisting the EHS division in identifying and minimizing or eliminating potential environmental hazards in the workplace. The largest source of air pollutants on the site is the electric furnace that generates CO, CO2, NOx, SO2, PM, and HAPs. In addition to the electric furnace, the facility has several natural gas combustion units and stationary diesel engines. Wastewater at the facility consists of stormwater, groundwater infiltration, and non-contact cooling water. Wastewater is treated for reuse in the cooling and dust control processes. The excess water is discharged into the nearby waterbody. The other major gaseous byproducts of its operations are CO, H2S, SO2, and benzene. It also generates 50,000 lb of K061/week, which it treats and disposes of at its facilities. The mill uses hydrochloric acid, sulfuric acid, and methylene chloride in the finishing operations. The facility has Title V Operating permits for CO, NOx, and SO2 and a TPDES permit. Among its reporting requirements include GHG, Air Emissions Inventory, Tier II Chemical Reports, and Industrial and Hazardous Waste Annual Waste Summary.

In the past year, the following events occurred that could have compromised the environment and the health and safety of the workers and its surrounding community:

• On October 18, 2021, two employees reported that they were unduly exposed to benzene while doing maintenance on the coke-making batteries.
• On February 5, 2022, the SO2 control system for the electric furnace failed resulting in heavy emissions of SO2.
• On April 13, 2022, 2,000 gallons of methylene chloride spilled and reached the nearby stream.
• Last month, it was sued by the EPA because it improperly disposed of treated K061 on its facilities.

Tasks

You are tasked to address the aforementioned issues. An estimate of the total amount of SO2 that was released unabated for three months while the control system is being fixed is due to TCEQ at the end of the month. You coordinated the response to the methylene chloride spill and now must submit a follow-up report. The company must also respond to the lawsuit on K061 disposal and you are expected to be involved in its defense of the practice.

Questions that might be asked:

Human Health Concerns

1. What are the human health risks from benzene, SO2, methylene chloride, and K061 that were released?

2. What immediate measures should be taken to minimize human health risks for the onsite emergency responders to methylene chloride?

3. What should be done to protect worker health and safety of the individuals that will work on site whenever there is a release of contaminant such as methylene chloride? What type of PPE and monitoring might be recommended for the first responders, and then individuals conducting the follow up Phase II site investigation and remediation? Should XYZ Steel Mill, Inc. have evacuation zones and/or muster points in response to the methylene chloride spill? What type of health and safety training do you believe all site personnel should have?

4. What are the acute effects and chronic effects of exposure to these chemicals?

5. What ambient air concentration of benzene is immediately dangerous to life and health? What health and safety threshold values apply to protect worker health and safety?

6. What tools/instruments would you recommend in the future to assess the exposure to benzene and other pollutants on site?

7. How would you estimate the population exposures to SO2 concentrations in ambient air? What factors will affect your estimate?

8. What regulatory agencies will be involved in the human health side of the sudden release of benzene and methylene chloride?

Environmental Concerns

1. What are the ecological risks from the contaminants (SO2, methylene chloride, K061) that were released?

2. What regulations apply to the manufacture, use, and or treatment of such pollutants (SO2, methylene chloride, K061)?

3. What regulatory agencies must be notified of the methylene chloride spill and which agency (agencies) will oversee the remediation efforts?

4. What regulatory agency must be notified of the unabated release of SO2?

5. What type(s) of remediation would you recommend for environmental impacts to soil and groundwater for methylene chloride?

6. What regulatory agencies establish protective and/or maximum concentration limits in soil and groundwater? How are these limits used/compared when evaluating effectiveness of remediation?

7. What are the treatment standards and management options for K061? If it's treated, can it be disposed of in or on a landfill?

8. If, you were tasked to prove that the treated K061 is no longer hazardous as a result of a lawsuit, what tools/methods would you use to provide the bases for this claim?

9. What models/tools are available to model the ways the contaminants in K061 move from the source through the environmental media and receptors?