Nalco Holding Co. (NYSE: NLC) shares jumped 24.2% to $35.86 after pest-control services provider Ecolab Inc. (NYSE: ECL) said it would acquire the water-treatment company for about $5.4 billion. Volume for Nalco amounted to 22.2 million shares, towering over a daily average of just better than one million.

The company out of Napierville, Illinois put out a news release saying that, under the terms of the agreement, which was unanimously approved by the boards of directors of both companies, Nalco’s shareholders may elect to receive either 0.7005 share of Ecolab common stock per share of Nalco common stock or $38.80 in cash, without interest, per share of Nalco common stock.

Nalco CEO J. Erik Fyrwald was quoted in the release as saying, “This is a strategically and financially compelling transaction that brings together two highly complementary businesses — combining Nalco’s leading positions in water and energy services with Ecolab’s strength in the food and beverage, health-care and institutional markets.

“Moreover, this transaction delivers substantial value to our shareholders through an immediate premium to Nalco’s share price as well as the opportunity to participate in the upside potential of the combined company. We are confident that our strong momentum, along with the combined enterprise’s significant financial resources, will enable us to deliver both accelerated growth and improved profitability.”

Nalco Company prides itself as being the world’s largest sustainability services company focused on industrial water, energy and air applications. The company says it helps customers reduce energy, water and other natural resource consumption, minimizing environmental releases while boosting the bottom line.