‘Pine needle tea’ taxes Kremmling’s water treatment capacity
June 30, 2010
Nearly a decade after the pine beetle epidemic first began claiming thousand of acres of pine trees across Northern Colorado, growing blankets of fallen pine needles are beginning to impact the water supply in Kremmling.
The problem is particularly acute in the spring when pine needles steep in the melting snow and runoff, creating something of an organic tea, high in acidity and organic carbon.
These compounds (leachate and fulvic acid) are difficult to remove through traditional treatment methods and can be carcinogenic (cancer causing) when combined with chlorine, the most common chemical used to treat water.
Kremmling’s 30-year-old water treatment plant recently failed to meet Environmental Protection Agency standards for the removal of these “total organic carbons” from its water supply.
While the town has temporarily solved the problem, and the water in Kremmling is safe to drink, according to the town’s Public Works Director Doug Moses, Kremmling will have to continue reporting its violation every quarter for the next 12 months.
Plant managers will also continue to research alternative ways to deal with the problem, including a possible reclassification of the treatment plant that would eliminate the testing requirement.
Trees, like anything that isn’t mineral in nature, are made of organic carbon, Moses explained. As the trees and their leaves or needles decay, the deteriorating organic matter is released into the environment.
“With a healthy forest, there is always some shedding,” Moses said. “But, in the beetle kill forest, all that organic mass has to get back into environment somehow. Unless it burns, in which case the carbon is released into the atmosphere and comes down with the rain, it decomposes into the soil and water.”
The water soluble organic compounds that result from the decay of deciduous leaves are easier to remove through the traditional water treatment process than the compounds from coniferous trees.
Moses stressed that the level of acceptable total organic carbon in the Kremmling water supply was exceeded by only a tenth of one percent, yet that was enough to trigger the violation.
Moses has adjusted treatment measures at the plant to address the emerging issue and has sought advice and guidance from the Colorado Department of Public Health and Environment, the Colorado Rural Water Association, Nalco (the plant’s water treatment chemical supplier) and research scientists at CU Boulder.
These agencies advised Moses to change the way he tests the water to measure instead for “specific ultraviolet absorbence” (SUVA). Under this option, the system is required to show that the amount of total organic carbons removed by the plant is equal or greater to the amount that must be removed according to the regulation.
By measuring what has been removed from the water rather than what hasn’t, the treatment plant has been able to meet a different set of EPA standards and, therefore, is on track to be back in compliance within the year. (Although current testing levels are acceptable, it will take a full year to bring up the 12-month average, Moses said.)
“The plant is easily in compliance with SUVA testing,” Moses said.
Heading into the future, Moses said he may seek a reclassification for the plant since it no longer meets the requirements of a conventional treatment plant.
“Our system is really more of a direct filtration process,” Moses said.
If the plant is reclassified, “the requirement to test for total organic carbons goes away completely,” Moses said. Even membrane filtration plants, which are considered one of the most state-of-the-art systems on the market today, don’t completely remove organic carbons, he added.
Kremmling’s water supply comes primarily from Sheep Creek, which flows out of the Gore Range, Moses said.
– Reid Armstrong can be reached at 970-887-3334 ext. 19610 or firstname.lastname@example.org.