The Power of Information

National Drinking Water Database


Riverview Wd Utilities - San Diego, CA


Serves 16,000 people

MTBE

MTBE (methyl tert-butyl ether) is a fuel additive that had been used as an octane enhancer in unleaded gasoline; it contaminates groundwater due to spillage or leakage at gas stations, and has been banned or scheduled for phaseout in most states.
 
This Drinking Water System
Test Days Exceeding Health GuidelinesDefinition of what this is
118 days
Test Days Exceeding Legal LimitsNumber of days in which the samples taken in that day exceed the Maximum Contaminant Level (Depending on the contaminant and its MCL, that may or may not trigger an MCL violation. Some MCLs are based on averages spanning several months to a year)
0 days
Test DaysNumber of days in which this chemical has reported results in the data we received from the State
855 days
Tests ConductedNumber of individual tests done for this contaminant
1,451 tests

Testing Summary

ContaminantAverage/
Maximum
Result
Health Limit
Exceeded
Legal Limit
Exceeded

Testing History

-Tested      -Detected      -Over Health Guidelines      -Over Legal Limit*
MTBEMTBE (methyl tert-butyl ether) is a fuel additive that had been used as an octane enhancer in unleaded gasoline; it contaminates groundwater due to spillage or leakage at gas stations, and has been banned or scheduled for phaseout in most states.7.04 ppb
94.5 ppb
Yes
13 ppb
Legal at any levelThis is the Federal Limit. State Limits may be lower.
NOTE: Each dot in the above graph represents one month.
* Water utilities are noted as exceeding the legal limit if any test is above the maximum contaminant level (MCL). Most MCLs are based on annual averages so exceeding the MCL for one test does not necessarily indicate that the system is out of compliance.

Health Based and Legal Limits for MTBE

Health Based Limits for MTBE

StandardDescriptionLevel
California Public Health GoalsDefined by the State of California Office of Environmental Health Hazard Assessment (OEHHA) as the level of contaminant that is allowed in drinking water. For acutely toxic substances, levels are set at which scientific evidence indicates that no known or anticipated adverse effects on health will occur, plus an adequate margin-of safety. PHGs for carcinogens or other substances which can cause chronic disease shall be based solely on health effects without regard to cost impacts and shall be set at levels which OEHHA has determined do not pose any significant risk to health.13 ppb

Testing Results

Testing DateAverage
Result
Samples taken that dayNumber of Non-DetectsRange of Results
2006-10-1621.49 ppb506.51 to 46.3 ppb
2006-10-155.02 ppb105.02 ppb
2006-10-144.67 ppb104.67 ppb
2006-10-1310.1 ppb1010.1 ppb
2006-10-128.88 ppb108.88 ppb
2006-10-114.58 ppb104.58 ppb
2006-10-1020.65 ppb505.73 to 44.8 ppb
2006-10-098.76 ppb108.76 ppb
2006-10-0811.1 ppb1011.1 ppb
2006-10-076.82 ppb106.82 ppb
2006-10-068 ppb108 ppb
2006-10-059.51 ppb109.51 ppb
2006-10-043.7 ppb103.7 ppb
2006-10-036.03 ppb106.03 ppb
2006-10-0214.74 ppb720 to 45.7 ppb
2006-10-015.95 ppb105.95 ppb
2006-09-303.6 ppb103.6 ppb
2006-09-296.89 ppb106.89 ppb
2006-09-287.71 ppb107.71 ppb
2006-09-277.26 ppb107.26 ppb
2006-09-267.17 ppb107.17 ppb
2006-09-2521.2 ppb505.55 to 46 ppb
2006-09-243.71 ppb103.71 ppb
2006-09-233.27 ppb103.27 ppb
2006-09-220 ppb110 ppb
2006-09-213.7 ppb103.7 ppb
2006-09-204.97 ppb104.97 ppb
2006-09-197.16 ppb107.16 ppb
2006-09-1812.37 ppb406.14 to 24.3 ppb
2006-09-170 ppb110 ppb
2006-09-164.85 ppb104.85 ppb
2006-09-153.62 ppb103.62 ppb
2006-09-130 ppb110 ppb
2006-09-1212.47 ppb720 to 35.2 ppb
2006-09-1111.61 ppb603.09 to 26.1 ppb
2006-09-104.34 ppb104.34 ppb
2006-09-094.41 ppb104.41 ppb
2006-09-084.35 ppb104.35 ppb
2006-09-076.51 ppb106.51 ppb
2006-09-067.18 ppb107.18 ppb
2006-09-055.35 ppb105.35 ppb
2006-09-043.8 ppb103.8 ppb
2006-09-034.64 ppb104.64 ppb
2006-09-026.88 ppb106.88 ppb
2006-09-016.88 ppb106.88 ppb
2006-08-314.26 ppb104.26 ppb
2006-08-305.8 ppb105.8 ppb
2006-08-290 ppb110 ppb
2006-08-2817.62 ppb505.94 to 35 ppb
2006-08-254.94 ppb104.94 ppb
2006-08-244.28 ppb104.28 ppb
2006-08-233.5 ppb103.5 ppb
2006-08-220 ppb110 ppb
2006-08-2118.7 ppb505.19 to 38.3 ppb
2006-08-203.69 ppb103.69 ppb
2006-08-194.17 ppb104.17 ppb
2006-08-183.57 ppb103.57 ppb
2006-08-170 ppb110 ppb
2006-08-160 ppb110 ppb
2006-08-150 ppb110 ppb
2006-08-1418.59 ppb505.22 to 38.3 ppb
2006-08-134.82 ppb104.82 ppb
2006-08-120 ppb110 ppb
2006-08-117.18 ppb107.18 ppb
2006-08-103.23 ppb103.23 ppb
2006-08-094.35 ppb104.35 ppb
2006-08-084.85 ppb104.85 ppb
2006-08-0717.69 ppb506.27 to 37.5 ppb
2006-08-060 ppb110 ppb
2006-08-057.51 ppb107.51 ppb
2006-08-045.79 ppb105.79 ppb
2006-08-036.73 ppb106.73 ppb
2006-08-025.03 ppb105.03 ppb
2006-07-313.42 ppb103.42 ppb
2006-07-303.41 ppb103.41 ppb
2006-07-294.36 ppb104.36 ppb
2006-07-285.9 ppb105.9 ppb
2006-07-273.78 ppb103.78 ppb
2006-07-264.27 ppb104.27 ppb
2006-07-254.47 ppb104.47 ppb
2006-07-2416.59 ppb505.08 to 36.1 ppb
2006-07-234.18 ppb104.18 ppb
2006-07-223.78 ppb103.78 ppb
2006-07-218.61 ppb108.61 ppb
2006-07-208.12 ppb108.12 ppb
2006-07-198.41 ppb108.41 ppb
2006-07-187.21 ppb107.21 ppb
2006-07-1718.85 ppb505.94 to 40.7 ppb
2006-07-168.53 ppb108.53 ppb
2006-07-156.95 ppb106.95 ppb
2006-07-147.41 ppb107.41 ppb
2006-07-137.16 ppb107.16 ppb
2006-07-124.56 ppb104.56 ppb
2006-07-111.74 ppb101.74 ppb
2006-07-1019.15 ppb505.43 to 40.9 ppb
2006-07-071.7 ppb101.7 ppb
2006-07-0615.05 ppb710 to 43.5 ppb
2006-07-053.41 ppb103.41 ppb
2006-07-043.01 ppb103.01 ppb
2006-07-033.51 ppb103.51 ppb
2006-07-020 ppb110 ppb
2006-07-014.75 ppb104.75 ppb
2006-06-300 ppb110 ppb
2006-06-2917.24 ppb504.4 to 37.5 ppb
2006-06-173.94 ppb103.94 ppb
2006-06-167.3 ppb107.3 ppb
2006-06-154.93 ppb104.93 ppb
2006-06-147.99 ppb107.99 ppb
2006-06-138.97 ppb108.97 ppb
2006-06-1222.75 ppb505.44 to 58.5 ppb
2006-06-116.78 ppb106.78 ppb
2006-06-107.01 ppb107.01 ppb
2006-06-092.97 ppb102.97 ppb
2006-06-083.44 ppb103.44 ppb
2006-06-072.29 ppb102.29 ppb
2006-06-064.37 ppb104.37 ppb
2006-06-0513.83 ppb505.14 to 31 ppb
2006-06-045.27 ppb105.27 ppb
2006-06-036.19 ppb106.19 ppb
2006-06-020 ppb110 ppb
2006-06-0114.36 ppb720 to 49 ppb
2006-05-315.12 ppb105.12 ppb
2006-05-306.28 ppb106.28 ppb
2006-05-295.88 ppb105.88 ppb
2006-05-286.22 ppb106.22 ppb
2006-05-275.71 ppb105.71 ppb
2006-05-262.4 ppb102.4 ppb
2006-05-256.13 ppb106.13 ppb
2006-05-243.49 ppb103.49 ppb
2006-05-233.59 ppb103.59 ppb
2006-05-2220.31 ppb505.46 to 50.7 ppb
2006-05-212.3 ppb102.3 ppb
2006-05-204.03 ppb104.03 ppb
2006-05-192.88 ppb102.88 ppb
2006-05-185.35 ppb105.35 ppb
2006-05-174.25 ppb104.25 ppb
2006-05-163.16 ppb103.16 ppb
2006-05-1514.15 ppb504.45 to 29.7 ppb
2006-05-145.46 ppb105.46 ppb
2006-05-134.73 ppb104.73 ppb
2006-05-124.05 ppb104.05 ppb
2006-05-114.47 ppb104.47 ppb
2006-05-104.08 ppb104.08 ppb
2006-05-092.17 ppb102.17 ppb
2006-05-0814.74 ppb502.36 to 30.5 ppb
2006-05-062.38 ppb102.38 ppb
2006-05-052.83 ppb102.83 ppb
2006-05-043.1 ppb103.1 ppb
2006-05-0316.49 ppb701.05 to 55 ppb
2006-05-023.34 ppb103.34 ppb
2006-05-015.93 ppb105.93 ppb
2006-04-304.61 ppb104.61 ppb
2006-04-293.47 ppb103.47 ppb
2006-04-283.5 ppb103.5 ppb
2006-04-274.84 ppb104.84 ppb
2006-04-263.23 ppb103.23 ppb
2006-04-252.43 ppb102.43 ppb
2006-04-2418.52 ppb504.85 to 42.8 ppb
2006-04-235.88 ppb105.88 ppb
2006-04-225.23 ppb105.23 ppb
2006-04-213.08 ppb103.08 ppb
2006-04-203.62 ppb103.62 ppb
2006-04-193.36 ppb103.36 ppb
2006-04-184.36 ppb104.36 ppb
2006-04-1714.52 ppb502.97 to 36.6 ppb
2006-04-164.67 ppb104.67 ppb
2006-04-155.37 ppb105.37 ppb
2006-04-146.36 ppb106.36 ppb
2006-04-135.78 ppb105.78 ppb
2006-04-125.56 ppb105.56 ppb
2006-04-115.55 ppb105.55 ppb
2006-04-1017.93 ppb502.6 to 42.2 ppb
2006-04-091.71 ppb101.71 ppb
2006-04-082.33 ppb102.33 ppb
2006-04-072.66 ppb102.66 ppb
2006-04-0614.37 ppb720 to 47.7 ppb
2006-04-051.76 ppb101.76 ppb
2006-04-042.28 ppb102.28 ppb
2006-04-0320.28 ppb503.23 to 51.5 ppb
2006-04-021.81 ppb101.81 ppb
2006-04-012.15 ppb102.15 ppb
2006-03-312.47 ppb102.47 ppb
2006-03-301.02 ppb101.02 ppb
2006-03-295.05 ppb105.05 ppb
2006-03-282.31 ppb102.31 ppb
2006-03-2720.07 ppb504.07 to 47.6 ppb
2006-03-263.74 ppb103.74 ppb
2006-03-253.99 ppb103.99 ppb
2006-03-244.44 ppb104.44 ppb
2006-03-235.29 ppb105.29 ppb
2006-03-223.71 ppb103.71 ppb
2006-03-212.03 ppb102.03 ppb
2006-03-2017.57 ppb503.47 to 46.4 ppb
2006-03-190 ppb110 ppb
2006-03-183.07 ppb103.07 ppb
2006-03-1718.83 ppb504.92 to 42.8 ppb
2006-03-164.81 ppb104.81 ppb
2006-03-153.19 ppb103.19 ppb
2006-03-144.96 ppb104.96 ppb
2006-03-135.12 ppb105.12 ppb
2006-03-124.14 ppb104.14 ppb
2006-03-114.36 ppb104.36 ppb
2006-03-103.7 ppb103.7 ppb
2006-03-095.18 ppb105.18 ppb
2006-03-085.48 ppb105.48 ppb
2006-03-0710.75 ppb720 to 35 ppb
2006-03-064.35 ppb104.35 ppb
2006-03-050 ppb110 ppb
2006-03-043.06 ppb103.06 ppb
2006-03-033.37 ppb103.37 ppb
2006-03-020 ppb110 ppb
2006-03-015.02 ppb105.02 ppb
2006-02-284.45 ppb104.45 ppb
2006-02-2716.83 ppb505.22 to 38.4 ppb
2006-02-264.35 ppb104.35 ppb
2006-02-253.72 ppb103.72 ppb
2006-02-243.38 ppb103.38 ppb
2006-02-230 ppb110 ppb
2006-02-223.2 ppb103.2 ppb
2006-02-2120.9 ppb505.55 to 49.9 ppb
2006-02-205.19 ppb105.19 ppb
2006-02-195.49 ppb105.49 ppb
2006-02-184.86 ppb104.86 ppb
2006-02-175.4 ppb105.4 ppb
2006-02-165.26 ppb105.26 ppb
2006-02-153.4 ppb103.4 ppb
2006-02-1414.06 ppb720 to 51.7 ppb
2006-02-134.51 ppb104.51 ppb
2006-02-123.91 ppb103.91 ppb
2006-02-110 ppb110 ppb
2006-02-1019.33 ppb510 to 51.8 ppb
2006-02-093.92 ppb103.92 ppb
2006-02-083.8 ppb103.8 ppb
2006-02-070 ppb110 ppb
2006-02-060 ppb110 ppb
2006-02-053.63 ppb103.63 ppb
2006-02-043.72 ppb103.72 ppb
2006-02-033.15 ppb103.15 ppb
2006-02-024.18 ppb104.18 ppb
2006-02-0119.44 ppb504.09 to 47.2 ppb
2006-01-310 ppb110 ppb
2006-01-303.28 ppb103.28 ppb
2006-01-294.06 ppb104.06 ppb
2006-01-283.74 ppb103.74 ppb
2006-01-273.69 ppb103.69 ppb
2006-01-263.46 ppb103.46 ppb
2006-01-253.56 ppb103.56 ppb
2006-01-243.03 ppb103.03 ppb
2006-01-2313.58 ppb520 to 35.8 ppb
2006-01-220 ppb110 ppb
2006-01-210 ppb110 ppb
2006-01-200 ppb110 ppb
2006-01-190 ppb110 ppb
2006-01-1715.58 ppb520 to 41.1 ppb
2006-01-160 ppb110 ppb
2006-01-150 ppb110 ppb
2006-01-140 ppb110 ppb
2006-01-130 ppb110 ppb
2006-01-120 ppb110 ppb
2006-01-119.62 ppb109.62 ppb
2006-01-1011.95 ppb730 to 40 ppb
2006-01-097 ppb107 ppb
2006-01-089.99 ppb109.99 ppb
2006-01-075.33 ppb105.33 ppb
2006-01-065.28 ppb105.28 ppb
2006-01-056.8 ppb106.8 ppb
2006-01-048.86 ppb108.86 ppb
2006-01-0314.45 ppb504.34 to 30.1 ppb
2006-01-026.29 ppb106.29 ppb
2006-01-015.45 ppb105.45 ppb
2005-12-316.54 ppb106.54 ppb
2005-12-305.85 ppb105.85 ppb
2005-12-296.04 ppb106.04 ppb
2005-12-2815.4 ppb503.91 to 32.5 ppb
2005-12-278.32 ppb108.32 ppb
2005-12-265.84 ppb105.84 ppb
2005-12-256.2 ppb106.2 ppb
2005-12-245.73 ppb105.73 ppb
2005-12-235.83 ppb105.83 ppb
2005-12-224.17 ppb104.17 ppb
2005-12-214.75 ppb104.75 ppb
2005-12-207.69 ppb107.69 ppb
2005-12-1914.93 ppb503.26 to 32.5 ppb
2005-12-189.67 ppb109.67 ppb
2005-12-176.34 ppb106.34 ppb
2005-12-166.11 ppb106.11 ppb
2005-12-156.29 ppb106.29 ppb
2005-12-1411.71 ppb710 to 34.5 ppb
2005-12-135.8 ppb105.8 ppb
2005-12-125.82 ppb105.82 ppb
2005-12-115.02 ppb105.02 ppb
2005-12-105.56 ppb105.56 ppb
2005-12-094.22 ppb104.22 ppb
2005-12-087.06 ppb107.06 ppb
2005-12-068.52 ppb108.52 ppb
2005-11-2820.96 ppb405.54 to 33.7 ppb
2005-11-2713.1 ppb1013.1 ppb
2005-11-2613.2 ppb1013.2 ppb
2005-11-258.66 ppb108.66 ppb
2005-11-2410.3 ppb1010.3 ppb
2005-11-236.66 ppb106.66 ppb
2005-11-226.3 ppb106.3 ppb
2005-11-2121.12 ppb405.18 to 37.7 ppb
2005-11-208.5 ppb108.5 ppb
2005-11-199.48 ppb109.48 ppb
2005-11-1811 ppb1011 ppb
2005-11-1710.5 ppb1010.5 ppb
2005-11-167.62 ppb107.62 ppb
2005-11-1518.29 ppb404.6 to 32.7 ppb
2005-11-147.76 ppb107.76 ppb
2005-11-136.44 ppb106.44 ppb
2005-11-126.07 ppb106.07 ppb
2005-11-116.3 ppb106.3 ppb
2005-11-106.55 ppb106.55 ppb
2005-11-0911.9 ppb1011.9 ppb
2005-11-0814.85 ppb610 to 37.3 ppb
2005-11-075.94 ppb105.94 ppb
2005-11-069.97 ppb109.97 ppb
2005-11-0510.6 ppb1010.6 ppb
2005-11-0410.6 ppb1010.6 ppb
2005-11-0311.3 ppb1011.3 ppb
2005-11-029.81 ppb109.81 ppb
2005-11-014.88 ppb104.88 ppb
2005-10-3132.8 ppb407.18 to 59.6 ppb
2005-10-3011.8 ppb1011.8 ppb
2005-10-2913.4 ppb1013.4 ppb
2005-10-2814 ppb1014 ppb
2005-10-277.16 ppb107.16 ppb
2005-10-2625.56 ppb406.55 to 43.1 ppb
2005-10-235.12 ppb105.12 ppb
2005-10-217.57 ppb107.57 ppb
2005-10-208.37 ppb108.37 ppb
2005-10-1921.89 ppb408.87 to 34.8 ppb
2005-10-150 ppb110 ppb
2005-10-149.59 ppb109.59 ppb
2005-10-1311.2 ppb1011.2 ppb
2005-10-1215.81 ppb710 to 39.1 ppb
2005-10-1119.6 ppb408.08 to 36.4 ppb
2005-10-094.03 ppb104.03 ppb
2005-10-087.62 ppb107.62 ppb
2005-10-077.47 ppb107.47 ppb
2005-10-0522.84 ppb406.21 to 39.2 ppb
2005-10-018.92 ppb108.92 ppb
2005-09-309.24 ppb109.24 ppb
2005-09-2916.54 ppb406.65 to 28.1 ppb
2005-09-168.22 ppb108.22 ppb
2005-09-145.46 ppb105.46 ppb
2005-09-135.2 ppb105.2 ppb
2005-09-129.87 ppb620 to 23.1 ppb
2005-09-118.9 ppb108.9 ppb
2005-09-105.76 ppb105.76 ppb
2005-09-095.72 ppb105.72 ppb
2005-09-086.27 ppb106.27 ppb
2005-09-077 ppb107 ppb
2005-09-0619.45 ppb404.18 to 34.8 ppb
2005-09-050 ppb110 ppb
2005-09-0410.8 ppb1010.8 ppb
2005-09-0310.8 ppb1010.8 ppb
2005-09-025.96 ppb105.96 ppb
2005-09-018.4 ppb108.4 ppb
2005-08-3022.13 ppb405.13 to 38.7 ppb
2005-08-297.32 ppb107.32 ppb
2005-08-2810.4 ppb1010.4 ppb
2005-08-2710.6 ppb1010.6 ppb
2005-08-265.15 ppb105.15 ppb
2005-08-255.92 ppb105.92 ppb
2005-08-2224.82 ppb405.86 to 40.7 ppb
2005-08-217.87 ppb107.87 ppb
2005-08-205.86 ppb105.86 ppb
2005-08-1912.1 ppb1012.1 ppb
2005-08-1817.59 ppb510 to 41.5 ppb
2005-08-1711.8 ppb1011.8 ppb
2005-08-168.05 ppb108.05 ppb
2005-08-1521.2 ppb405.19 to 35 ppb
2005-08-140 ppb110 ppb
2005-08-1312 ppb1012 ppb
2005-08-1210.6 ppb1010.6 ppb
2005-08-1110.9 ppb1010.9 ppb
2005-08-1011.9 ppb1011.9 ppb
2005-08-0912.6 ppb1012.6 ppb
2005-08-0821.01 ppb405.42 to 34.9 ppb
2005-08-0710.8 ppb1010.8 ppb
2005-08-066.61 ppb106.61 ppb
2005-08-0514.4 ppb1014.4 ppb
2005-08-0411.2 ppb1011.2 ppb
2005-08-0112.7 ppb620 to 34.2 ppb
2005-07-316.46 ppb106.46 ppb
2005-07-3011.1 ppb1011.1 ppb
2005-07-2911.6 ppb1011.6 ppb
2005-07-2820.07 ppb405.49 to 32 ppb
2005-07-2714.6 ppb1014.6 ppb
2005-07-248.56 ppb108.56 ppb
2005-07-236.86 ppb106.86 ppb
2005-07-2214 ppb1014 ppb
2005-07-2126.56 ppb405.72 to 49.8 ppb
2005-07-2016.6 ppb1016.6 ppb
2005-07-1813.7 ppb1013.7 ppb
2005-07-1713.9 ppb1013.9 ppb
2005-07-1612.7 ppb1012.7 ppb
2005-07-1513.1 ppb1013.1 ppb
2005-07-1414.2 ppb1014.2 ppb
2005-07-1320.69 ppb504.1 to 45.7 ppb
2005-07-129.45 ppb109.45 ppb
2005-07-1012.8 ppb1012.8 ppb
2005-07-0913.6 ppb1013.6 ppb
2005-07-0820.6 ppb1020.6 ppb
2005-07-0712.4 ppb1012.4 ppb
2005-07-0611.5 ppb1011.5 ppb
2005-07-0517.04 ppb710 to 50.3 ppb
2005-07-047.6 ppb107.6 ppb
2005-07-0311.3 ppb1011.3 ppb
2005-07-0211.6 ppb1011.6 ppb
2005-07-0110.7 ppb1010.7 ppb
2005-06-3010.5 ppb1010.5 ppb
2005-06-299.93 ppb109.93 ppb
2005-06-2810.2 ppb1010.2 ppb
2005-06-2616.99 ppb702.52 to 45.3 ppb
2005-06-2511.4 ppb1011.4 ppb
2005-06-2410.9 ppb1010.9 ppb
2005-06-234.55 ppb104.55 ppb
2005-06-229.42 ppb109.42 ppb
2005-06-217.36 ppb107.36 ppb
2005-06-2016.82 ppb503.4 to 35 ppb
2005-06-193.4 ppb103.4 ppb
2005-06-187.4 ppb107.4 ppb
2005-06-177.7 ppb107.7 ppb
2005-06-167.3 ppb107.3 ppb
2005-06-157.1 ppb107.1 ppb
2005-06-1414.57 ppb710 to 42.9 ppb
2005-06-137.2 ppb107.2 ppb
2005-06-124.1 ppb104.1 ppb
2005-06-116.4 ppb106.4 ppb
2005-06-103.3 ppb103.3 ppb
2005-05-206 ppb106 ppb
2005-05-193.7 ppb103.7 ppb
2005-05-183.4 ppb103.4 ppb
2005-05-175.3 ppb105.3 ppb
2005-05-1614.54 ppb503.3 to 30 ppb
2005-05-153.6 ppb103.6 ppb
2005-05-145.5 ppb105.5 ppb
2005-05-137.2 ppb107.2 ppb
2005-05-126.1 ppb106.1 ppb
2005-05-117.8 ppb107.8 ppb
2005-05-107.6 ppb107.6 ppb
2005-05-0919.86 ppb504 to 44.2 ppb
2005-05-086.3 ppb106.3 ppb
2005-05-071.8 ppb101.8 ppb
2005-05-061.6 ppb101.6 ppb
2005-05-056.39 ppb1150 to 25.2 ppb
2005-05-044.7 ppb104.7 ppb
2005-04-266 ppb106 ppb
2005-04-2517.23 ppb410 to 32 ppb
2005-04-243 ppb103 ppb
2005-04-230 ppb110 ppb
2005-04-224 ppb104 ppb
2005-04-213.6 ppb103.6 ppb
2005-04-2031 ppb1031 ppb
2005-04-194.3 ppb104.3 ppb
2005-04-1813.48 ppb501.7 to 31 ppb
2005-04-165.6 ppb105.6 ppb
2005-04-137.2 ppb107.2 ppb
2005-04-129.2 ppb109.2 ppb
2005-04-1122.28 ppb403.1 to 42 ppb
2005-04-099 ppb109 ppb
2005-04-084 ppb104 ppb
2005-04-0712.83 ppb720 to 37 ppb
2005-04-0611 ppb1011 ppb
2005-03-304.2 ppb104.2 ppb
2005-03-294.3 ppb104.3 ppb
2005-03-2820.8 ppb503.6 to 46.6 ppb
2005-03-273 ppb103 ppb
2005-03-264 ppb104 ppb
2005-03-257.9 ppb107.9 ppb
2005-03-240 ppb110 ppb
2005-03-2217.62 ppb510 to 46 ppb
2005-03-216.3 ppb106.3 ppb
2005-03-209.2 ppb109.2 ppb
2005-03-194 ppb104 ppb
2005-03-188.3 ppb108.3 ppb
2005-03-179.6 ppb109.6 ppb
2005-03-169.2 ppb109.2 ppb
2005-03-153.9 ppb103.9 ppb
2005-03-1419.1 ppb510 to 45 ppb
2005-03-133.8 ppb103.8 ppb
2005-03-123.2 ppb103.2 ppb
2005-03-114.1 ppb104.1 ppb
2005-03-103.6 ppb103.6 ppb
2005-03-090 ppb110 ppb
2005-03-088.6 ppb108.6 ppb
2005-03-017.1 ppb107.1 ppb
2005-02-2819.76 ppb510 to 33.8 ppb
2005-02-273.1 ppb103.1 ppb
2005-02-265.2 ppb105.2 ppb
2005-02-258.4 ppb108.4 ppb
2005-02-248.1 ppb108.1 ppb
2005-02-238.6 ppb108.6 ppb
2005-02-2215.7 ppb502.9 to 33.7 ppb
2005-02-215.5 ppb105.5 ppb
2005-02-205.3 ppb105.3 ppb
2005-02-195 ppb105 ppb
2005-02-184.2 ppb104.2 ppb
2005-02-175.9 ppb105.9 ppb
2005-02-168 ppb108 ppb
2005-02-158.1 ppb108.1 ppb
2005-02-0722.78 ppb403.8 to 46.2 ppb
2005-02-0114.17 ppb710 to 41.3 ppb
2005-01-317.3 ppb107.3 ppb
2005-01-303.8 ppb103.8 ppb
2005-01-295.9 ppb105.9 ppb
2005-01-289 ppb109 ppb
2005-01-273 ppb103 ppb
2005-01-264.5 ppb104.5 ppb
2005-01-257.6 ppb107.6 ppb
2005-01-2417.98 ppb502.9 to 44 ppb
2005-01-236.4 ppb106.4 ppb
2005-01-223.7 ppb103.7 ppb
2005-01-2117.18 ppb503 to 43.2 ppb
2005-01-205.5 ppb105.5 ppb
2005-01-133.9 ppb103.9 ppb
2005-01-127.1 ppb107.1 ppb
2005-01-115.3 ppb105.3 ppb
2005-01-1019.28 ppb503.3 to 48 ppb
2005-01-098.6 ppb108.6 ppb
2005-01-083.9 ppb103.9 ppb
2005-01-074.9 ppb104.9 ppb
2005-01-066 ppb106 ppb
2005-01-0516.71 ppb710 to 58 ppb
2005-01-047.9 ppb107.9 ppb
2005-01-038 ppb108 ppb
2005-01-025.6 ppb105.6 ppb
2005-01-015.2 ppb105.2 ppb
2004-12-314.9 ppb104.9 ppb
2004-12-308.7 ppb108.7 ppb
2004-12-297 ppb107 ppb
2004-12-284.9 ppb104.9 ppb
2004-12-2717 ppb601.8 to 50.8 ppb
2004-12-267.5 ppb107.5 ppb
2004-12-255.9 ppb105.9 ppb
2004-12-244 ppb104 ppb
2004-12-237.2 ppb107.2 ppb
2004-12-227.7 ppb107.7 ppb
2004-12-217.8 ppb107.8 ppb
2004-12-2021.24 ppb503.4 to 57.9 ppb
2004-12-195.9 ppb105.9 ppb
2004-12-184.8 ppb104.8 ppb
2004-12-176.7 ppb106.7 ppb
2004-12-164.4 ppb104.4 ppb
2004-12-154.3 ppb104.3 ppb
2004-12-147.8 ppb107.8 ppb
2004-12-1320.62 ppb602.8 to 63.9 ppb
2004-12-128.4 ppb108.4 ppb
2004-12-118.8 ppb108.8 ppb
2004-12-109.4 ppb109.4 ppb
2004-12-095.2 ppb105.2 ppb
2004-12-088.8 ppb108.8 ppb
2004-12-079.1 ppb109.1 ppb
2004-12-0619.48 ppb602.6 to 62 ppb
2004-12-058.3 ppb108.3 ppb
2004-12-045.9 ppb105.9 ppb
2004-12-038.2 ppb108.2 ppb
2004-12-0215.69 ppb710 to 59 ppb
2004-11-308.3 ppb108.3 ppb
2004-11-293.8 ppb103.8 ppb
2004-11-284.4 ppb104.4 ppb
2004-11-278.7 ppb108.7 ppb
2004-11-263.8 ppb103.8 ppb
2004-11-254.2 ppb104.2 ppb
2004-11-247.2 ppb107.2 ppb
2004-11-208.2 ppb108.2 ppb
2004-11-199.2 ppb109.2 ppb
2004-11-187.6 ppb107.6 ppb
2004-11-174.3 ppb104.3 ppb
2004-11-164 ppb104 ppb
2004-11-1523.42 ppb503.9 to 63.6 ppb
2004-11-147.6 ppb107.6 ppb
2004-11-137.2 ppb107.2 ppb
2004-11-126.9 ppb106.9 ppb
2004-11-106.5 ppb106.5 ppb
2004-11-096.5 ppb106.5 ppb
2004-11-0820.66 ppb503.7 to 53.8 ppb
2004-11-077 ppb107 ppb
2004-11-066.7 ppb106.7 ppb
2004-11-055.8 ppb105.8 ppb
2004-11-048.4 ppb108.4 ppb
2004-11-032.8 ppb102.8 ppb
2004-11-027.9 ppb107.9 ppb
2004-11-0110.07 ppb610 to 26.4 ppb
2004-10-316.5 ppb106.5 ppb
2004-10-308.7 ppb108.7 ppb
2004-10-292.7 ppb102.7 ppb
2004-10-2610.6 ppb1010.6 ppb
2004-10-2530.76 ppb504.3 to 88.3 ppb
2004-10-2411.4 ppb1011.4 ppb
2004-10-235.7 ppb105.7 ppb
2004-10-2211.6 ppb1011.6 ppb
2004-10-2111.4 ppb1011.4 ppb
2004-10-2010.8 ppb1010.8 ppb
2004-10-1910.5 ppb1010.5 ppb
2004-10-1828.02 ppb504.1 to 76.3 ppb
2004-10-179.6 ppb109.6 ppb
2004-10-1611.6 ppb1011.6 ppb
2004-10-1511.6 ppb1011.6 ppb
2004-10-1410.6 ppb1010.6 ppb
2004-10-1310.7 ppb1010.7 ppb
2004-10-1226.78 ppb504 to 75.5 ppb
2004-10-1111 ppb1011 ppb
2004-10-109.2 ppb109.2 ppb
2004-10-0911.9 ppb1011.9 ppb
2004-10-085.2 ppb105.2 ppb
2004-10-079.8 ppb109.8 ppb
2004-10-0621.2 ppb710 to 87.6 ppb
2004-10-055.1 ppb105.1 ppb
2004-10-045.7 ppb105.7 ppb
2004-10-035.4 ppb105.4 ppb
2004-10-029.4 ppb109.4 ppb
2004-10-0111.7 ppb1011.7 ppb
2004-09-308.6 ppb108.6 ppb
2004-09-2910.4 ppb1010.4 ppb
2004-09-283.5 ppb103.5 ppb
2004-09-2728.8 ppb402.9 to 77.1 ppb
2004-09-267.7 ppb107.7 ppb
2004-09-257.2 ppb107.2 ppb
2004-09-245 ppb105 ppb
2004-09-235.7 ppb105.7 ppb
2004-09-223.4 ppb103.4 ppb
2004-09-2122.66 ppb502.9 to 77.1 ppb
2004-09-193.5 ppb103.5 ppb
2004-09-181.9 ppb101.9 ppb
2004-09-178.3 ppb108.3 ppb
2004-09-162.2 ppb102.2 ppb
2004-09-156.3 ppb106.3 ppb
2004-09-144.6 ppb104.6 ppb
2004-09-1316.63 ppb810 to 71.3 ppb
2004-09-126.2 ppb106.2 ppb
2004-09-116.5 ppb106.5 ppb
2004-09-094.6 ppb104.6 ppb
2004-09-084 ppb104 ppb
2004-09-0716.48 ppb504.2 to 43.8 ppb
2004-09-064.9 ppb104.9 ppb
2004-09-053.4 ppb103.4 ppb
2004-09-040 ppb110 ppb
2004-08-210 ppb110 ppb
2004-08-203.5 ppb103.5 ppb
2004-08-193.3 ppb103.3 ppb
2004-08-180 ppb110 ppb
2004-08-170 ppb110 ppb
2004-08-1626.48 ppb503.3 to 84.5 ppb
2004-08-154.4 ppb104.4 ppb
2004-08-144.5 ppb104.5 ppb
2004-08-133.9 ppb103.9 ppb
2004-08-123.1 ppb103.1 ppb
2004-08-114.2 ppb104.2 ppb
2004-08-105.2 ppb105.2 ppb
2004-08-0917.19 ppb820 to 93.5 ppb
2004-08-052.2 ppb102.2 ppb
2004-08-0412.4 ppb1012.4 ppb
2004-08-038.6 ppb108.6 ppb
2004-07-2624.94 ppb502.7 to 80.4 ppb
2004-07-2594.5 ppb1094.5 ppb
2004-07-249.3 ppb109.3 ppb
2004-07-238.6 ppb108.6 ppb
2004-07-228.6 ppb108.6 ppb
2004-07-213.1 ppb103.1 ppb
2004-07-208 ppb108 ppb
2004-07-1920.54 ppb503 to 63.3 ppb
2004-07-176.3 ppb106.3 ppb
2004-07-167.1 ppb107.1 ppb
2004-07-156 ppb106 ppb
2004-07-146.7 ppb106.7 ppb
2004-07-136.8 ppb106.8 ppb
2004-07-126.4 ppb106.4 ppb
2004-07-115.8 ppb105.8 ppb
2004-07-104.9 ppb104.9 ppb
2004-07-093.4 ppb103.4 ppb
2004-07-082.4 ppb102.4 ppb
2004-07-0716.22 ppb501.2 to 55.9 ppb
2004-07-063.6 ppb103.6 ppb
2004-07-052.1 ppb102.1 ppb
2004-07-045 ppb105 ppb
2004-07-035.5 ppb105.5 ppb
2004-07-0213.51 ppb710 to 53.9 ppb
2004-07-014.6 ppb104.6 ppb
2004-06-306.2 ppb106.2 ppb
2004-06-2916.98 ppb502.6 to 46.2 ppb
2004-06-281.6 ppb101.6 ppb
2004-06-276 ppb204.9 to 7.1 ppb
2004-06-262.4 ppb102.4 ppb
2004-06-251.9 ppb101.9 ppb
2004-06-242.9 ppb102.9 ppb
2004-06-234.1 ppb104.1 ppb
2004-06-223.3 ppb103.3 ppb
2004-06-2114.82 ppb502.8 to 39.1 ppb
2004-06-203.9 ppb103.9 ppb
2004-06-194.4 ppb104.4 ppb
2004-06-183.9 ppb103.9 ppb
2004-06-173.8 ppb103.8 ppb
2004-06-161.3 ppb101.3 ppb
2004-06-153.7 ppb103.7 ppb
2004-06-1411.62 ppb510 to 27.6 ppb
2004-06-133.3 ppb103.3 ppb
2004-06-123 ppb103 ppb
2004-06-112.5 ppb102.5 ppb
2004-06-102.7 ppb102.7 ppb
2004-06-091.5 ppb101.5 ppb
2004-06-081.7 ppb101.7 ppb
2004-06-0712.12 ppb502.5 to 26.3 ppb
2004-06-061.9 ppb101.9 ppb
2004-06-052.9 ppb102.9 ppb
2004-06-042.4 ppb102.4 ppb
2004-06-032.8 ppb102.8 ppb
2004-06-022.5 ppb102.5 ppb
2004-06-019.41 ppb720 to 28 ppb
2004-05-313.9 ppb103.9 ppb
2004-05-304.2 ppb104.2 ppb
2004-05-294.3 ppb104.3 ppb
2004-05-284 ppb104 ppb
2004-05-274.1 ppb104.1 ppb
2004-05-263.3 ppb103.3 ppb
2004-05-253.6 ppb103.6 ppb
2004-05-2412.52 ppb502.7 to 27.9 ppb
2004-05-230 ppb110 ppb
2004-05-223 ppb103 ppb
2004-05-210 ppb110 ppb
2004-05-203.1 ppb103.1 ppb
2004-05-193.1 ppb103.1 ppb
2004-05-183 ppb103 ppb
2004-05-1712.84 ppb502.9 to 30.3 ppb
2004-05-163.5 ppb103.5 ppb
2004-05-153.3 ppb103.3 ppb
2004-05-142.6 ppb102.6 ppb
2004-05-132.8 ppb102.8 ppb
2004-05-122.7 ppb102.7 ppb
2004-05-111.7 ppb101.7 ppb
2004-05-1012.24 ppb501.9 to 27.3 ppb
2004-05-092.1 ppb102.1 ppb
2004-05-082.6 ppb102.6 ppb
2004-05-072 ppb102 ppb
2004-05-062.6 ppb102.6 ppb
2004-05-0512.12 ppb502.1 to 29.8 ppb
2004-05-048.9 ppb720 to 30.2 ppb
2004-05-032.9 ppb102.9 ppb
2004-05-023.4 ppb103.4 ppb
2004-05-013.2 ppb103.2 ppb
2004-04-302.3 ppb102.3 ppb
2004-04-291.1 ppb101.1 ppb
2004-04-282.5 ppb102.5 ppb
2004-04-272.6 ppb102.6 ppb
2004-04-2610.32 ppb502.2 to 23.7 ppb
2004-04-252.1 ppb102.1 ppb
2004-04-242 ppb102 ppb
2004-04-230 ppb110 ppb
2004-04-221.8 ppb101.8 ppb
2004-04-210 ppb110 ppb
2004-04-201.9 ppb101.9 ppb
2004-04-1912.84 ppb501.7 to 29.6 ppb
2004-04-181.3 ppb101.3 ppb
2004-04-171.7 ppb101.7 ppb
2004-04-161.9 ppb101.9 ppb
2004-04-152.2 ppb102.2 ppb
2004-04-141.7 ppb101.7 ppb
2004-04-131.8 ppb101.8 ppb
2004-04-1211.24 ppb501.8 to 26.2 ppb
2004-04-110 ppb110 ppb
2004-04-100 ppb110 ppb
2004-04-091.2 ppb101.2 ppb
2004-04-082 ppb102 ppb
2004-04-079.33 ppb720 to 32 ppb
2004-04-060 ppb110 ppb
2004-04-051.7 ppb101.7 ppb
2004-04-041.2 ppb101.2 ppb
2004-04-031.6 ppb101.6 ppb
2004-04-022 ppb102 ppb
2004-04-011.9 ppb101.9 ppb
2004-03-311.9 ppb101.9 ppb
2004-03-302.1 ppb102.1 ppb
2004-03-2914.68 ppb501.9 to 32.7 ppb
2004-03-281.1 ppb101.1 ppb
2004-03-271.2 ppb101.2 ppb
2004-03-261.6 ppb101.6 ppb
2004-03-251.7 ppb101.7 ppb
2004-03-241.6 ppb101.6 ppb
2004-03-231.1 ppb101.1 ppb
2004-03-228.93 ppb410 to 24.3 ppb
2004-03-211.1 ppb101.1 ppb
2004-03-201.1 ppb101.1 ppb
2004-03-190 ppb110 ppb
2004-03-180 ppb110 ppb
2004-03-170 ppb110 ppb
2004-03-160 ppb110 ppb
2004-03-156.56 ppb520 to 22.9 ppb
2004-03-140 ppb110 ppb
2004-03-130 ppb110 ppb
2004-03-120 ppb110 ppb
2004-03-091 ppb101 ppb
2004-03-0811.7 ppb401.1 to 32.2 ppb
2004-03-061 ppb101 ppb
2004-03-051 ppb101 ppb
2004-03-041 ppb101 ppb
2004-03-024.9 ppb730 to 24.6 ppb
2004-03-011 ppb101 ppb
2004-02-291 ppb101 ppb
2004-02-281 ppb101 ppb
2004-02-270 ppb110 ppb
2004-02-261 ppb101 ppb
2004-02-250 ppb110 ppb
2004-02-241 ppb101 ppb
2004-02-234.7 ppb410 to 11.9 ppb
2004-02-221.1 ppb101.1 ppb
2004-02-210 ppb110 ppb
2004-02-200 ppb110 ppb
2004-02-191 ppb101 ppb
2004-02-186.8 ppb410 to 19.5 ppb
2004-02-170 ppb110 ppb
2004-02-160 ppb110 ppb
2004-02-150 ppb110 ppb
2004-02-140 ppb110 ppb
2004-02-130 ppb110 ppb
2004-02-120 ppb110 ppb
2004-02-110 ppb110 ppb
2004-02-100 ppb110 ppb
2004-02-096.26 ppb520 to 21.3 ppb
2004-02-081.7 ppb101.7 ppb
2004-02-070 ppb110 ppb
2004-02-060 ppb110 ppb
2004-02-050 ppb110 ppb
2004-02-040 ppb110 ppb
2004-02-030 ppb110 ppb
2004-02-023.68 ppb620 to 15.6 ppb
2004-02-011 ppb101 ppb
2004-01-310 ppb110 ppb
2004-01-301 ppb101 ppb
2004-01-291.4 ppb101.4 ppb
2004-01-281.1 ppb101.1 ppb
2004-01-271 ppb101 ppb
2004-01-266.18 ppb510 to 20.2 ppb
2004-01-251 ppb101 ppb
2004-01-241 ppb101 ppb
2004-01-230 ppb110 ppb
2004-01-225.2 ppb105.2 ppb
2004-01-211 ppb101 ppb
2004-01-203.42 ppb510 to 9 ppb
2004-01-191.6 ppb101.6 ppb
2004-01-181 ppb101 ppb
2004-01-171 ppb101 ppb
2004-01-161 ppb101 ppb
2004-01-151.9 ppb101.9 ppb
2004-01-1210.3 ppb610 to 26.7 ppb
2004-01-081.8 ppb101.8 ppb
2004-01-077.23 ppb720 to 26.5 ppb
2004-01-061.3 ppb101.3 ppb
2004-01-051 ppb101 ppb
2004-01-041 ppb101 ppb
2004-01-031.2 ppb101.2 ppb
2004-01-021.2 ppb101.2 ppb
2004-01-010 ppb110 ppb