EPA’s 98% Emissions Rule: How FlexCore™ Ensures Floating Roof Tank Seal Compliance

Can Your Tank Seals Meet the New 98% Efficiency Standard?

The Environmental Protection Agency (EPA) has tightened regulations for storage tanks, introducing stricter requirements under 40 CFR 60 Subpart Kc. These updated standards now require 98% emissions efficiency for floating roof tanks, up from 95% under Subpart Kb. This change presents new challenges for tank operators, who must now rethink sealing solutions, maintenance schedules, and operational procedures to remain compliant.


Why the New EPA Regulations Matter

The EPA’s move to a 98% emissions threshold is part of a broader effort to reduce volatile organic compound (VOC) emissions, minimize environmental impact, and improve air quality. For tank operators, this shift has real-world implications:

  • Non-compliance risks: Fines, operational shutdowns, and increased oversight are immediate consequences for failing to meet the new standards (which are already in effect).
  • Higher scrutiny: Regulatory audits are likely to become more frequent and thorough, especially as the new regulation applies to new, reconstructed, or modified tanks.
  • New Requirements: Changes to previously approved seal systems upsets the seal status quo (and makes liquid-mounted seals a requirement over mechanical shoe seals in some tanks).

The bottom line: upgrading your seals is not just an option – it’s a compliance necessity.


FlexCore™: Engineered for 98% Efficiency

Mesa ETP’s FlexCore™ is specifically designed to help operators meet these new EPA requirements while maximizing reliability and minimizing maintenance. Here’s why FlexCore™ stands out:

  1. Compliance ready design
    FlexCore™ meets the latest regulatory standards for liquid-mounted seals, giving tank operators confidence in achieving 98% emissions control.
  2. Direct liquid-mounted seal
    Unlike vapor-mounted or mechanical shoe designs, FlexCore™ maintains a consistent seal, reducing vapor losses even under fluctuating tank conditions.
  3. Armor Fabric™ durability
    High-strength Armor Fabric™ reinforces the seal, ensuring long-term performance and resistance to wear, especially in challenging external floating roof tanks with slotted guide poles.

By combining these innovations, FlexCore™ provides a reliable, low-maintenance solution that keeps operators ahead of regulatory changes.


Benefits Beyond Compliance

Upgrading to FlexCore™ offers more than just regulatory assurance:

  • Reliable emissions control: Consistently meets or exceeds new EPA regulations, reducing environmental impact and keeping tanks compliant.
  • Cost savings: Reduces your emissions output while also minimizing downtime and maintenance costs associated with seal failure or regulatory violations.
  • Long service life: Advanced materials (like Armor Fabric™) reduce wear and help get you through your maintenance cycle smoothly.
  • Operational flexibility: Ideal for both new builds and retrofits of existing tanks.

Case in Point: Real-World Tank Challenges

Consider a terminal operating multiple external floating roof tanks with slotted guide poles. By upgrading to FlexCore™, the operator can:

  • Maintain consistent emissions control above the 98% threshold.
  • Reduce the need for frequent seal replacement or fabric failures.

Lower your emissions and gain benefits on permitting and compliance.


Key Takeaways for Tank Operators

  1. Assess your current seals: Determine whether your existing system can reliably meet 98% emissions efficiency. Remember the EPA has strict guidelines on what constitutes a liquid-mounted seal, so make sure your system meets those criteria.
  2. Consider direct liquid-mounted solutions: Products like FlexCore™ are engineered to maintain performance under challenging conditions.
  3. Factor in durability and maintenance: Armor Fabric™ and an abrasion resistant seal design minimize operational interruptions and long-term costs.

Stay compliant and proactive: Early adoption and operations checks ensure smoother regulatory audits and uninterrupted operations.


Learn More About EPA 98% Emissions Regulations and FlexCore™