News Release 019
Additional test results received from Hannibal's drinking water supply
Volume 38-019 (For Immediate Release)
Contact: Judd Slivka
573-751-1010 (after hours)
JEFFERSON CITY, MO. -- Jan. 15, 2010 -- The Missouri Department of Natural Resource received new test results from Hannibal's drinking water supply Friday.
Chromium-6 levels were consistent with sampling done on Jan. 5. As before, the finished water sample was above the Missouri Department of Health and Senior Services'-set health-screening level of 0.4 parts per billion (ppb).
Consistent with previous evaluations, and based on consultations with the U.S. Environmental Protection Agency and DHSS, the public drinking water is safe to drink.
Samples taken from the Hannibal public drinking water plant on Jan. 13 showed the following levels of chromium-6 present in the water:
Water measured at the plant's intake: 0.1 ppb
After the pre-sedimentation basin: 0.1 ppb
After the primary flocculation and settling basin: <0.1 ppb
After the secondary settling basin: 0.5 ppb
After the filter feed basin: 0.5 ppb
After filtering: 0.5 ppb
After final chlorination: 0.6 ppb
Water measured at a pump station 2 miles downstream: 0.5 ppb
The City of Louisiana's water was sampled as well, and results of both its raw and finished water were below the health-screening level.
The department continues to investigate the issue of chromium-6 levels in these public drinking water supplies and is in close contact with both Hannibal and Louisiana officials.
Currently, no state in the country has a drinking water standard for hexavalent chromium. However, the state of Missouri does have a standard for total chromium (measuring both hexavalent and trivalent chromium) of 100 parts per billion; both cities' systems are in compliance with that standard. Both cities are entirely in compliance with Missouri's public drinking water standards, as well.
DNR has created a web page with links to studies and previous press releases at dnr.mo.gov/chromium.