Water-Data Report 2008 01646564 MILL CREEK AT DALECARLIA RESERVOIR NEAR CHEVY CHASE, MD Potomac Basin Middle Potomac-Anacostia-Occoquan Subbasin

LOCATION.--Lat 38°56'44.3", long 77°06'28.4" referenced to North American Datum of 1983, Montgomery County, MD, Hydrologic Unit 02070010. WATER-QUALITY RECORDS PERIOD OF RECORD.--December 2007.

WATER-QUALITY DATA WATER YEAR OCTOBER 2007 TO SEPTEMBER 2008 Part 1 of 3 [Remark codes: E, estimated.] Turb- Specif. Specif- idity, pH, pH, conduc- ic IR LED water, water, tance, conduc- light, Dis- unfltrd unfltrd wat unf tance, Temper- det ang solved field, lab, lab, wat unf ature, 90 deg, oxygen, std std µS/cm µS/cm water, Date Time Sample medium and type FNU mg/L units units 25 degC 25 degC deg C (63680) (00300) (00400) (00403) (90095) (00095) (00010) Dec 10... 1210 Surface water, regular 16 7.5 7.2 7.3 979 994 10.1

WATER-QUALITY DATA WATER YEAR OCTOBER 2007 TO SEPTEMBER 2008 Part 2 of 3 [Remark codes: E, estimated.] ANC, Nitrate Total wat unf + nitro- Magnes- Potas- fixed Chlor- Fluor- Silica, Ammonia nitrite Nitrite gen, Calcium ium, sium, Sodium, end pt, ide, ide, water, Sulfate water, water water, wat unf water, water, water, water, lab, water, water, fltrd, water, fltrd, fltrd, fltrd, by anal fltrd, fltrd, fltrd, fltrd, mg/L as fltrd, fltrd, mg/L as fltrd, mg/L mg/L mg/L ysis, Date mg/L mg/L mg/L mg/L CaCO3 mg/L mg/L SiO2 mg/L as N as N as N mg/L (00915) (00925) (00935) (00930) (90410) (00940) (00950) (00955) (00945) (00608) (00631) (00613) (62855) Dec 10... 39.1 11.4 6.71 142 81 233 .38 7.3 33.3 E.018 .83 .023 1.57

U.S. Department of the Interior U.S. Geological Survey Water-Data Report 2008 01646564 MILL CREEK DALECARLIA SW-4—Continued

WATER-QUALITY DATA WATER YEAR OCTOBER 2007 TO SEPTEMBER 2008 Part 3 of 3 [Remark codes: E, estimated.] Ortho- phos- Phos- phate, phorus, Mangan- water, water, Iron, ese, Sam- fltrd, unfltrd water, water, Sampler pling mg/L mg/L fltrd, fltrd, type, method, Date as P as P µg/L µg/L code code (00671) (00665) (01046) (01056) (84164) (82398) Dec 10... .371 .46 265 124 4080 4080

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