Ash Pond Dewatering

Solutions to meet coal combustion residuals compliance with ash pond closures

Did you know?

With new federal regulations for flue gas waste and coal combustion residuals (CCR) in effect, energy companies making the transition from coal-fired to gas-fired power generation are taking action to reclaim CCR storage ponds. The regulations prohibit further storage of CCR waste in surface impoundments and encourage producers to treat, dewater and decommission ponds as soon as is practically possible.

Evoqua offers temporary and permanent water and wastewater treatment solutions to meet ELG and CCR requirements for coal-fired plants

How can Evoqua help?

Evoqua’s solutions for ash pond dewatering in support of pond closures include temporary and permanent treatment equipment for the removal of suspended solids and metals. Technologies include ballasted clarification, media filtration, settling tanks and transfer systems. If required, polishing equipment can be utilized including Vantage® reverse osmosis systems and wastewater ion exchange reactive media, or Frontier's SeHAWK® bioreactor system.

Advanced treatments for arsenic, mercury and selenium are also available when tighter outfall limits are present. Solids waste is typically concentrated, pressed, and dewatered with the resultant solid cake returned to the pond prior to capping or disposed at landfill.

As regulations evolve, coal-fired power plants will need to make decisions related to environmental strategies, treatment technologies, and implementation. Full scale systems require advance planning, engineering, and project management to allow for a cost-effective solution to meet compliance deadlines. 

Solutions to Meet Effluent Limits Include: