EPA Wants Injection Well Water Cleaned Up

Viewpoint: Agreement would improve how wastewater is managed

July 20, 2011

In the next few days, the Maui County’s elected officials will consider signing an agreement with the U.S. Environmental Protection Agency that would significantly improve how local wastewater is managed, and substantially increase the supply of recycled wastewater available for reuse. It will also have the effect of better protecting the precious marine waters of West Maui.

The county’s three sewage treatment plants process about 15 million gallons of partially treated wastewater into the ground each day. One-third of this amount is coming from the Lahaina wastewater facility. More than 15 years ago, the EPA required the county to apply for a federal underground injection control permit to cover the Lahaina operation. Although the permit has expired, the county is authorized to continue operating in accordance with the same permit conditions while the EPA considers reissuance.

The permit reissuance has been delayed over issues such as where the wastewater goes once it is placed in the disposal wells, whether it is treated enough and its potential effect on the aquifer and nearshore waters. Scientists have detected some pollution from the Lahaina injection wells in the shallow coastal waters of West Maui. Therefore, the EPA has ordered a study to shed light on the wastewater’s underground path and its travel time from the Lahaina facility to the coast. This involves placing dye into the injection wells and monitoring areas where freshwater seeps into the ocean for signs of the dye. We expect to have the findings of this study available later this year.

Meanwhile, the EPA is proposing to update the county’s injection permit with improved treatment requirements, including full disinfection of all wastewater and increased pollution reduction. This would increase Lahaina’s daily sewage flow receiving full disinfection and provide additional reclaimed water to support Maui’s needs. At the same time, we are encouraging the county to develop the infrastructure necessary to realize its longer term goal of completely phasing out injection wells in favor of reusing the water.

We welcome the recent unanimous approval by the Maui County Council Policy Committee of a proposed bill authorizing the county to enter into a legal agreement with the EPA regarding Lahaina’s injection wells. The bill, which needs ratification by the entire County Council, would require ultraviolet disinfection of 100 percent of wastewater at the Lahaina facility by 2013 – a significant step forward from the current 20 percent.

Working together, Maui County, its citizens and the EPA can make great strides in managing water resources and protecting Maui’s world-famous coastal waters for years to come.

* Alexis Strauss is the Water Division director for the U.S. Environmental Protection Agency’s Pacific Southwest Region.