Despite completion of a $100,000 cleanup operation at an old dumpsite in the Howard Preserve in Bellevue, residents will be warned in perpetuity to stay clear of contaminated waste in the area.
The Idaho Department of Environmental Quality informed the Bellevue City Council four years ago that contaminated dirt covering about 3,000 square feet of land in the city park needed to be removed and replaced with clean fill dirt and vegetation.
The site had been used as a dump since the 1880s and contained dangerous materials, including lead and elevated levels of arsenic. The materials were used generations ago in the manufacture of glass and ceramics, and were byproducts of mining operations and foundry work. The DEQ said the dirt would need to be disposed of, replaced and planted over.
Aaron Scheff, DEQ brownfields program manager, told the council last week that the cleanup, which began last summer, was complete, paid for with a grant from the federal government. He said the city would have to pay legal fees to set up a "land covenant," attached to the area's title, for the contaminated area that will prohibit residential development and water extraction in perpetuity. Since the area is on city-owned property and within the flood plain, development is virtually impossible in any case.
A buck fence has been built to keep pedestrians off the site. Scheff said he will also plant formidable rose bushes that will keep people out for years to come. He said these measures were necessary because plenty of unhealthy materials are still in the ground, extending to a depth of 10 feet.
"It would have cost us millions of dollars to pull it all out," he said.
The toxic site lies adjacent to a walking trail that diverges southward from the irrigation canal into the heart of the Howard Preserve. A small portion of the dump lies underneath the trail.
Scheff said 6 to 12 inches of soil was removed from the area and taken to the Milner Butte landfill in Burley, a regulated and permitted dump site.
A "geo-textile" barrier was laid down on top of the dirty soil before the clean soil and vegetation were applied. Schepp said the barrier would allow plant roots to reach the soil but limit leeching of dangerous materials into groundwater or into the nearby Big Wood River.
"In the old days, dumps were put in drainages and next to rivers," Schepp said. "I worry about those areas much more than I worry about permitted and regulated landfills. It's a good thing it was moved."
Tony Evans: firstname.lastname@example.org