In a third round of test results released earlier this month, county officials saw little cause for concern about lead levels in Arlington water.
In testing 127 homes of varying ages, scattered around the county, county staff found only five homes with lead levels above an “action level” of 15 parts per billion, or ppb, set by the U.S. Environmental Protection Agency, below the 10 percent threshold requiring greater action by the county.
These tests do not end water testing in the county, said Randy Bartlett, the county’s director of infrastructure and operations. “We’ll be doing testing in the next few weeks in multi-family units.”
Overall, however, Bartlett said the most recent round of tests shows little reason for Arlingtonians to start worrying about the water coming out of their taps. “Our water system is meeting all federal and state standards,” he said. “It’s operating the same as it’s been operating since we started lead and copper testing in 1992.”
That doesn’t mean everyone will stop worrying, said Laura Dely, a member of the Civic Federation’s Environmental Committee. In an e-mail this week, Dely wrote, “I don’t think this issue is over.”
Testing apartments is just starting, she said, and those tests may be the most important to most residents. “As most Arlington residents live in … apartment units, and the county isn’t checking more than a handful … there will be additional worries,” Dely wrote.
<b>IN TEST RESULTS</b> released on April 9, the county showed that, of the 127 homes tested most recently, 54 are homes built between 1983 and 1986, homes that the EPA says are most at risk for high lead levels.
Of those 54 homes, three showed lead levels higher than the action level on the “first draw” samples, water collected after the home’s water system has sat unused for six hours or more.
Water samples collected from those homes fell below the 15 parts per billion level when water was flushed from the system for 90 seconds.
Of the 73 other homes tested, only two others showed high lead levels, which also fell below the action level after a 90-second flush.
Those 73 homes were built from 1910-2002, an age range of homes that would include homes built when lead pipes were in wider use.
Bartlett said that so far, the county has found no homes with lead pipes. “If anybody has them, show them to us. We’ll test them,” he said.
The real concern, he said, and the basis for the EPA’s testing regime, are homes with copper pipes sealed with lead solder. As concerns about the Washington area’s water supply now focus on the water treatments used at the Dalecarlia Water Treatment Plant, Bartlett said he expects to see few changes.
Local governments and Congressional hearings have raised questions about whether a shift from chlorine to chloramines in the water treatment increased the corrosiveness of water passing through a system with lead solder. Arlington tests do not bear out those concerns. said Bartlett.
“Based on the results we’ve seen, the water system is acting the same way it’s always acted on the pipes,” he said “We’ve always had a few results over 15, and this says to me that chloramines haven’t changed that.”
<b>LINKS BETWEEN LEAD</b> levels in water and lead levels in blood are fuzzy, but when children or pregnant women are involved, no one wants to wait to see conclusive proof, said Robert Jonas, George Mason University environmental science professor.
“My answer is, if you feel uncomfortable, filter the water you put into you,” he said.
Dely agreed. “I flush my taps for 90-120 [seconds] … and I use a Brita filter for all drinking and cooking needs,” she wrote.
Public confidence in local water systems has been shaken by the way water lead levels came to light, Jonas said. “From a public policy perspective, what’s going on right now is probably the worst of all possible worlds. The public doesn’t have a way of exercising best judgment.”
But in all likelihood, Jonas said, the risk from lead levels in water is the least of local environmental worries — there is a clearer, and more widespread risk, from ozone levels that rise during the summer. “I tell people, ‘Worry about the air you’re breathing, don’t worry about the air you’re drinking.’”
<b>Effect of Flushing</b>
<table border=1 cellpadding=2 cellspacing=0><tr><td><b>Type of Sample*</b></td><td><b>#</b></td><td><b># > 15 ppb</b></td></tr><tr><td><b>1st Draw</b></td><td>127</td><td>5</td></tr><tr><td><b>After 90-sec. flush</b></td><td>122</td><td>0</td></tr><tr><td><b>After 5-min. flush</b></td><td>75</td><td>0</td></tr><tr><td><b>Mid-day</b></td><td>11</td><td>0</td></tr></table>
<i>*In the third round of tests, the county collected water samples from 127 homes at different intervals.</i>
<b>Elevated Lead Levels</b>
<table border=1 cellpadding=2 cellspacing=0>
<tr><td><b>House</b></td><td><b>Built</b></td><td><b>1st draw</b></td><td><b>After 90-sec. flush</b></td></tr><tr><b>Homes from EPA Tier (built 1983-1986)</b></tr><tr><td><b>1</b></td><td>1985</td><td>19.7 ppb</td><td>4.5 ppb</td></tr><tr><td><b>2</b></td><td>1983</td><td>17.2 ppb</td><td>not taken</td></tr><tr><td><b></b></td><td></td><td>1.3 ppb (Test b)</td><td>0.0 ppb</td></tr><tr><td><b>3</b></td><td>1985</td><td>16.6 ppb</td><td>0.7 ppb</td></tr><tr><b>Homes From Expanded Sample</b></tr><tr><td><b>4</b></td><td>1938</td><td>99.2 ppb</td><td>0.0 ppb</td></tr><tr><td><b>5</b></td><td>1942</td><td>49.0 ppb</td><td>3.7 ppb</td></tr></table>