1.  Availability and characteristics of data on MTBE in drinking water
    used in the 12-State study^1^

\[CWSs, community water systems; MTBE, methyl *tert*-butyl ether; μg/L,
micrograms per liter**;** NA, not applicable; mg/L, milligrams per
liter\]

+------+----+----+----+----+------------+-------------+------------+
| S    | Nu | Nu | Nu | Pe | Analytical | Source and  | Data       |
| tate | mb | mb | mb | ri | reporting  | status      | processing |
|      | er | er | er | od | levels     |             |            |
|      | of | of |    |    |            | of MTBE     | performed  |
|      |    |    | of | of | used by    | data        | by USGS    |
|      | ra | ra |    |    | State      |             |            |
|      | nd | nd | M  | re | lab(s)     |             |            |
|      | om | om | TB | co |            |             |            |
|      | ly | ly | E\ | rd | (μg/L)     |             |            |
|      | se | se | an |    |            |             |            |
|      | le | le | al |    |            |             |            |
|      | ct | ct | ys |    |            |             |            |
|      | ed | ed | es |    |            |             |            |
|      | CW | CW |    |    |            |             |            |
|      | Ss | Ss |    |    |            |             |            |
|      | in | wi |    |    |            |             |            |
|      | s  | th |    |    |            |             |            |
|      | tu | MT |    |    |            |             |            |
|      | dy | BE |    |    |            |             |            |
|      | d  | da |    |    |            |             |            |
|      | es | ta |    |    |            |             |            |
|      | ig |    |    |    |            |             |            |
|      | n^ |    |    |    |            |             |            |
|      | 1^ |    |    |    |            |             |            |
+------+----+----+----+----+------------+-------------+------------+
| Con  | -  | -  | -  | 2  | 10, 5.0,   | Connecticut | files      |
| nect |    |    |    | /1 | 2.0, 1.0,  | Department  | scanned    |
| icut |  1 |  1 |  5 | 9/ | 0.5 and    | of Public   | and/or     |
|      | 20 | 20 | 07 | 93 | 0.2        | Health,     | typed into |
|      |    |    |    | -\ |            | Water       | database   |
|      |    |    |    | 12 |            | Supplies    |            |
|      |    |    |    | /3 |            | Section;    |            |
|      |    |    |    | 1/ |            | MTBE        |            |
|      |    |    |    | 97 |            | analyzed by |            |
|      |    |    |    |    |            | State and   |            |
|      |    |    |    |    |            | pri­vate     |            |
|      |    |    |    |    |            | labs, data  |            |
|      |    |    |    |    |            | on paper    |            |
|      |    |    |    |    |            | files       |            |
+------+----+----+----+----+------------+-------------+------------+
| Dela | -  | -  | -  | NA | NA         | Delaware    |            |
| ware |    |    |    |    |            | Health and  |            |
|      | 46 |  0 |  0 |    |            | Social      |            |
|      |    |    |    |    |            | Ser­vices,   |            |
|      |    |    |    |    |            | Division of |            |
|      |    |    |    |    |            | Public      |            |
|      |    |    |    |    |            | Health,     |            |
|      |    |    |    |    |            | Office of   |            |
|      |    |    |    |    |            | Drinking    |            |
|      |    |    |    |    |            | Water; no   |            |
|      |    |    |    |    |            | MTBE        |            |
|      |    |    |    |    |            | available   |            |
+------+----+----+----+----+------------+-------------+------------+
| M    | -  | -  | -  | 2  | 1.0        | Maine       | MTBE       |
| aine |    |    |    | /2 |            | Department  | populated  |
|      | 80 | 55 |  1 | 5/ |            | of Human    | as \<1.0   |
|      |    |    | 22 | 97 |            | Ser­vices,   | μg/L in    |
|      |    |    |    | -\ |            | Division of | all post   |
|      |    |    |    | 7  |            | Health      | Feb. 1997  |
|      |    |    |    | /2 |            | E           | samples    |
|      |    |    |    | 1/ |            | ngi­neering; | without    |
|      |    |    |    | 98 |            | MTBE        | detects    |
|      |    |    |    |    |            | analyzed in |            |
|      |    |    |    |    |            | samples run |            |
|      |    |    |    |    |            | by DOHS lab |            |
|      |    |    |    |    |            | since Feb.  |            |
|      |    |    |    |    |            | 1997,       |            |
|      |    |    |    |    |            | reported    |            |
|      |    |    |    |    |            | only when   |            |
|      |    |    |    |    |            | detected    |            |
+------+----+----+----+----+------------+-------------+------------+
| Mary | -  | -  | -  | 1/ | 0.5        | Maryland    | identified |
| land |    |    |    | 3/ |            | Department  | MTBE data  |
|      |  1 |  1 |  4 | 95 |            | of the      | as MDE     |
|      | 01 | 01 | 56 | -\ |            | E           | parameter  |
|      |    |    |    | 1/ |            | nvi­ronment, | 'VOC2251"  |
|      |    |    |    | 7/ |            | Water       | based on   |
|      |    |    |    | 98 |            | Supply      | USEPA      |
|      |    |    |    |    |            | Protec­tion  | parameter  |
|      |    |    |    |    |            | Program;    | code 2251  |
|      |    |    |    |    |            | MTBE        | for MTBE   |
|      |    |    |    |    |            | analyzed in |            |
|      |    |    |    |    |            | all samples |            |
|      |    |    |    |    |            | since Jan.  |            |
|      |    |    |    |    |            | 1995        |            |
+------+----+----+----+----+------------+-------------+------------+
| M    | -  | -  | -  | 1/ | 5.0, 2.0,  | Ma          | MTBE       |
| assa |    |    |    | 5/ | 1.0, and   | ssachusetts | populated  |
| chus |  1 | 75 |  2 | 93 | 0.5        | Department  | when not   |
| etts | 05 |    | 70 | -  |            | of          | detected   |
|      |    |    |    |    |            | En          | by review  |
|      |    |    |    | 1  |            | vi­ronmental | of paper   |
|      |    |    |    | 2/ |            | Protection, | files      |
|      |    |    |    | 7/ |            | Division of |            |
|      |    |    |    | 98 |            | Water       |            |
|      |    |    |    |    |            | Supply;     |            |
|      |    |    |    |    |            | MTBE        |            |
|      |    |    |    |    |            | analysis    |            |
|      |    |    |    |    |            | optional    |            |
|      |    |    |    |    |            | and         |            |
|      |    |    |    |    |            | reported    |            |
|      |    |    |    |    |            | only when   |            |
|      |    |    |    |    |            | detected    |            |
+------+----+----+----+----+------------+-------------+------------+
| New  | -  | -  | -  | 1/ | 0.5        | New         | MDL        |
| H    |    |    |    | 3/ |            | Hampshire   | populated  |
| amps |  1 |  1 |  3 | 95 |            | Department  | as \<0.5   |
| hire | 34 | 30 | 87 | -  |            | of          | μg/L for   |
|      |    |    |    |    |            | En          | all sample |
|      |    |    |    | 6  |            | vironmental | with "BDL" |
|      |    |    |    | /3 |            | Services,   | code for   |
|      |    |    |    | 0/ |            | Water       | non        |
|      |    |    |    | 98 |            | Supply      | detects    |
|      |    |    |    |    |            | Engineering |            |
|      |    |    |    |    |            | Bureau;     |            |
|      |    |    |    |    |            | MTBE        |            |
|      |    |    |    |    |            | analyzed by |            |
|      |    |    |    |    |            | DES lab     |            |
|      |    |    |    |    |            | since Jan.  |            |
|      |    |    |    |    |            | 1995        |            |
+------+----+----+----+----+------------+-------------+------------+
| New  | -  | -  | -  | 2/ | 2.0, 0.54, | New Jersey  | identified |
| Je   |    |    |    | 5/ | 0.5, 0.36, | Department  | MTBE data  |
| rsey |  1 | 65 |  5 | 97 | 0.3, 0.25, | of          | as NJDEP   |
|      | 22 |    | 10 | -  | 0.24,      | En          | code       |
|      |    |    |    |    | 0.12, and  | viron­mental | (AS_CONID  |
|      |    |    |    | 1  | 0.1        | Protection, | = 2251)    |
|      |    |    |    | 2/ |            | Division of | based on   |
|      |    |    |    | 8/ |            | Water       | USEPA      |
|      |    |    |    | 98 |            | Resources,  | parameter  |
|      |    |    |    |    |            | Bureau of   | code 2251  |
|      |    |    |    |    |            | Safe        | for MTBE   |
|      |    |    |    |    |            | Drinking    |            |
|      |    |    |    |    |            | Water; MTBE |            |
|      |    |    |    |    |            | ana­lyzed    |            |
|      |    |    |    |    |            | most        |            |
|      |    |    |    |    |            | samples     |            |
|      |    |    |    |    |            | since may   |            |
|      |    |    |    |    |            | 1997        |            |
+------+----+----+----+----+------------+-------------+------------+
| New  | -  | -  | -  | 1/ | 10, 5.0,   | New York    | MTBE data  |
| York |    |    |    | 5/ | 1.0, and   | Department  | listed     |
|      |  5 |  2 |  1 | 95 | 0.5        | of Health,  | under 6    |
|      | 38 | 41 | ,8 | -  |            | Bureau of   | param­eter  |
|      |    |    | 39 |    |            | Public      | name       |
|      |    |    |    | 12 |            | Water       | spellings  |
|      |    |    |    | /1 |            | Supply      | combined   |
|      |    |    |    | 5/ |            | Protection; |            |
|      |    |    |    | 98 |            | MTBE        |            |
|      |    |    |    |    |            | analysis    |            |
|      |    |    |    |    |            | required in |            |
|      |    |    |    |    |            | some        |            |
|      |    |    |    |    |            | counties,   |            |
|      |    |    |    |    |            | State,      |            |
|      |    |    |    |    |            | county, and |            |
|      |    |    |    |    |            | private     |            |
|      |    |    |    |    |            | labs        |            |
+------+----+----+----+----+------------+-------------+------------+
| Penn | -  | -  | -  | NA | NA         | P           |            |
| sylv |    |    |    |    |            | ennsylvania |            |
| ania |  4 |  0 |  0 |    |            | Department  |            |
|      | 43 |    |    |    |            | of          |            |
|      |    |    |    |    |            | En          |            |
|      |    |    |    |    |            | vi­ronmental |            |
|      |    |    |    |    |            | Protection, |            |
|      |    |    |    |    |            | Division of |            |
|      |    |    |    |    |            | Drinking    |            |
|      |    |    |    |    |            | Water       |            |
|      |    |    |    |    |            | Management; |            |
|      |    |    |    |    |            | no MTBE     |            |
|      |    |    |    |    |            | data        |            |
|      |    |    |    |    |            | available   |            |
+------+----+----+----+----+------------+-------------+------------+
| R    | -  | -  | -  | 1/ | 1.0 and    | Rhode       | no         |
| hode |    |    |    | 5/ | 0.5        | Island      | processing |
| Is   | 30 | 30 |  5 | 93 |            | Department  | required   |
| land |    |    | 11 | -  |            | of Health;  |            |
|      |    |    |    |    |            |             |            |
|      |    |    |    | 7/ |            | MTBE        |            |
|      |    |    |    | 9/ |            | analysis by |            |
|      |    |    |    | 98 |            | State lab   |            |
|      |    |    |    |    |            | since 1991  |            |
+------+----+----+----+----+------------+-------------+------------+
| Ver  | -  | -  | -  | 1/ | 2.0 and    | Vermont     | MTBE       |
| mont |    |    |    | 4/ | 1.0        | Department  | populated  |
|      | 87 | 75 |  1 | 95 |            | of          | when not   |
|      |    |    | 84 | -  |            | En          | detected   |
|      |    |    |    |    |            | viron­mental | by review  |
|      |    |    |    | 12 |            | Co          | of paper   |
|      |    |    |    | /2 |            | nservation, | files;     |
|      |    |    |    | 4/ |            | Water       | converted  |
|      |    |    |    | 97 |            | Sup­ply      | from mg/L  |
|      |    |    |    |    |            | Division;   | to μg/L    |
|      |    |    |    |    |            | MTBE        |            |
|      |    |    |    |    |            | reported    |            |
|      |    |    |    |    |            | only when   |            |
|      |    |    |    |    |            | detected    |            |
+------+----+----+----+----+------------+-------------+------------+
| Virg | -  | -  | -  | 1  | 0.5        | Virginia    | MTBE       |
| inia |    |    |    | /2 |            | Department  | populated  |
|      |  3 |  3 |  7 | 1/ |            | of Health,  | as \<0.5   |
|      | 04 | 02 | 24 | 97 |            | Office of   | μg/L for   |
|      |    |    |    | -  |            | Water       | all        |
|      |    |    |    |    |            | Programs;   | samples    |
|      |    |    |    | 2  |            | MTBE        | with non   |
|      |    |    |    | /2 |            | analyzed by | detects    |
|      |    |    |    | 4/ |            | State lab   | since      |
|      |    |    |    | 98 |            | in all      | April 1997 |
|      |    |    |    |    |            | samples     |            |
|      |    |    |    |    |            | since April |            |
|      |    |    |    |    |            | 1997 but    |            |
|      |    |    |    |    |            | not         |            |
|      |    |    |    |    |            | reported    |            |
|      |    |    |    |    |            | unless      |            |
|      |    |    |    |    |            | detected    |            |
+------+----+----+----+----+------------+-------------+------------+
| T    | -  | -  | -  | 1/ | 10, 5.0,   |             |            |
| otal |    |    |    | 5/ | 2.0, 1.0,  |             |            |
|      |  2 |  1 |  5 | 93 | 0.54, 0.5, |             |            |
|      | ,1 | ,1 | ,5 | -  | 0.36, 0.3, |             |            |
|      | 10 | 94 | 10 |    | 0.25,      |             |            |
|      |    |    |    | 12 | 0.24, 0.2, |             |            |
|      |    |    |    | /1 | 0.12, and  |             |            |
|      |    |    |    | 5/ | 0.1        |             |            |
|      |    |    |    | 98 |            |             |            |
+------+----+----+----+----+------------+-------------+------------+

^1^ the following U.S. Geological Survey reports, available at
<http://sd.water.usgs.gov/nawqa/vocns> or clickable below, document the
design, data analysis, and findings of the 12-State retrospective
assessment of MTBE in drinking water:

Grady, S.J. and Casey, G.D., 1999, A plan for assessing the occurrence
and distribution of methyl tert butyl ether and other volatile organic
compounds in drinking water and ambient ground water in the Northeast
and Mid-Atlantic Regions of the Unites States: U.S. Geological Survey
Open-File Report 99-207, 36 p. [(pdf
version)](http://sd.water.usgs.gov/nawqa/pubs/ofr/ofr99.207.pdf)

Grady, S.J., and Casey, G.D., 2001, Occurrence and distribution of
methyl tert-butyl ether and other volatile organic compounds in drinking
water in the Northeast and Mid-Atlantic regions of the United States,
1993-98: U.S. Geological Survey Water-Resources Investigations Report
00-4228, 123 p. [(pdf
version)](http://sd.water.usgs.gov/nawqa/pubs/wrir/wrir00.4228.pdf)

Moran, Michael, Grady, Stephen, and Zogorski, John, 2001, Occurrence and
distribution of volatile organic compounds in drinking water supplied by
community water systems in the Northeast and Mid-Atlantic regions of the
United States, 1993-98: U.S. Geological Survey Fact Sheet 089-01 4p.
[(pdf
version)](http://sd.water.usgs.gov/nawqa/pubs/factsheet/fs089_01.html)

Squillace P.J., and Moran, M.J., 2000, Estimating the likelihood of MTBE
occurrence in drinking water supplied by ground-water sources in the
Northeast and Mid-Atlantic regions of the United States: U.S. Geological
Survey Open-File Report 00-343, 10 p. [(pdf
version)](http://sd.water.usgs.gov/nawqa/pubs/ofr/ofr00.343.pdf)