Defender™ Tank Covers are custom manufactured from industrial-grade materials to fit the profile of your new or existing wastewater treatment tank or potable water tanks. Odorous gas emissions from wastewater treatment facilities generate complaints from local residents and are subject to the Clean Air Act Amendments of 1990. Defender™ odor control covers contain volatile organic compounds at their source. Low-profile, structurally supported covers minimize emission treatment volume to reduce the cost of air filtration equipment. Eliminate the ongoing expense of applying costly odor control chemicals through atomizers and misters.