Department of Ecology News Release - December 24, 2012


Imerys Minerals California Inc. fined for excessive particle pollution

SPOKANE — The Washington Department of Ecology (Ecology) has fined Imerys Minerals California Inc. (Imerys) of Quincy $120,000 for emitting more air particle pollution than is allowed by its permit.

Limiting particulate matter at industrial sites is important because the particles can harm human health.

The penalty includes a settlement that outlines an agreement that Imerys (formerly known as Celite Corp.) will pay a $60,000 fine. The additional $60,000 will pay for reducing diesel emissions from school buses in the Quincy School District.

Imerys processes diatomite, a fossilized mineral created by single-celled aquatic algae. Their fossilized remains have innate filtering characteristics due to their honeycomb structure. Their filtering qualities are used in beer and wine making, pharmaceutical manufacturing, motor oil processing, swimming pool water filtering, and in the food processing industry. Diatomite also serves as a soil amendment.

Ecology air quality inspectors found that Imerys may have failed to meet its permit limit for as many as 300 days. The company’s permit limits its emissions to 0.040 grains per dry standard cubic foot. But when tested in July 2010, the exhaust stack was emitting particulate matter at a concentration of 0.053 grains per cubic foot. In January 2011, the stack tested at 0.057.

By May 2011, the emissions once again met the permit limit.

Ecology updated the Imerys air quality permit to change some of the air pollution control monitoring procedures so that the company can maintain and verify continuous compliance with its permitted emissions limits.

Ecology’s permits are designed to protect the public from air pollution, thereby maintaining healthy communities that can attract additional economic growth.

Particulate matter from Imerys is of a different size and composition than that emitted from Quincy’s numerous data center emergency diesel engines. While both types of particulate matter are of air quality concern, they are regulated under different sets of rules.


Media Contact: Linda Kent, Communications, 360-407-6239; e-mail

For more information:

Ecology's Air channel (

Ecology’s social media (