00010
151
2002-11-20
2023-09-20
Temperature, water, degrees Celsius
00020
3
2002-11-20
2023-09-20
Temperature, air, degrees Celsius
00025
1
2002-11-20
2023-09-20
Barometric pressure, millimeters of mercury
00028
27
2002-11-20
2023-09-20
Agency analyzing sample, code
00061
123
2002-11-20
2023-09-20
Discharge, instantaneous, cubic feet per second
00063
112
2002-11-20
2023-09-20
Number of sampling points, count
00095
141
2002-11-20
2023-09-20
Specific conductance, water, unfiltered, microsiemens per centimeter at 25 degrees Celsius
00191
150
2002-11-20
2023-09-20
Hydrogen ion, water, unfiltered, calculated, milligrams per liter
00300
151
2002-11-20
2023-09-20
Dissolved oxygen, water, unfiltered, milligrams per liter
00301
40
2002-11-20
2023-09-20
Dissolved oxygen, water, unfiltered, percent of saturation
00310
118
2002-11-20
2023-09-20
Biochemical oxygen demand, water, unfiltered, 5 days at 20 degrees Celsius, milligrams per liter
00400
150
2002-11-20
2023-09-20
pH, water, unfiltered, field, standard units
00403
120
2002-11-20
2023-09-20
pH, water, unfiltered, laboratory, standard units
00405
120
2002-11-20
2023-09-20
Carbon dioxide, water, unfiltered, milligrams per liter
00417
121
2002-11-20
2023-09-20
Acid neutralizing capacity, water, unfiltered, fixed endpoint (pH 4.5) titration, laboratory, milligrams per liter as calcium carbonate
00515
48
2002-11-20
2023-09-20
Dissolved solids dried at 105 degrees Celsius, water, filtered, milligrams per liter
00530
123
2002-11-20
2023-09-20
Suspended solids, water, unfiltered, milligrams per liter
00600
112
2002-11-20
2023-09-20
Total nitrogen [nitrate + nitrite + ammonia + organic-N], water, unfiltered, milligrams per liter
00602
1
2002-11-20
2023-09-20
Total nitrogen [nitrate + nitrite + ammonia + organic-N], water, filtered, milligrams per liter
00605
11
2002-11-20
2023-09-20
Organic nitrogen, water, unfiltered, milligrams per liter as nitrogen
00608
1
2002-11-20
2023-09-20
Ammonia (NH3 + NH4+), water, filtered, milligrams per liter as nitrogen
00610
123
2002-11-20
2023-09-20
Ammonia (NH3 + NH4+), water, unfiltered, milligrams per liter as nitrogen
00615
121
2002-11-20
2023-09-20
Nitrite, water, unfiltered, milligrams per liter as nitrogen
00620
121
2002-11-20
2023-09-20
Nitrate, water, unfiltered, milligrams per liter as nitrogen
00630
1
2002-11-20
2023-09-20
Nitrate plus nitrite, water, unfiltered, milligrams per liter as nitrogen
00631
1
2002-11-20
2023-09-20
Nitrate plus nitrite, water, filtered, milligrams per liter as nitrogen
00650
121
2002-11-20
2023-09-20
Phosphate, water, unfiltered, milligrams per liter as PO4
00660
1
2002-11-20
2023-09-20
Orthophosphate, water, filtered, milligrams per liter as PO4
00665
122
2002-11-20
2023-09-20
Phosphorus, water, unfiltered, milligrams per liter as phosphorus
00666
1
2002-11-20
2023-09-20
Phosphorus, water, filtered, milligrams per liter as phosphorus
00671
1
2002-11-20
2023-09-20
Orthophosphate, water, filtered, milligrams per liter as phosphorus
00680
2
2002-11-20
2023-09-20
Organic carbon, water, unfiltered, milligrams per liter
00681
1
2002-11-20
2023-09-20
Organic carbon, water, filtered, milligrams per liter
00900
123
2002-11-20
2023-09-20
Hardness, water, milligrams per liter as calcium carbonate
00903
118
2002-11-20
2023-09-20
Noncarbonate hardness, water, unfiltered, lab, milligrams per liter as calcium carbonate
00915
116
2002-11-20
2023-09-20
Calcium, water, filtered, milligrams per liter
00916
120
2002-11-20
2023-09-20
Calcium, water, unfiltered, recoverable, milligrams per liter
00925
117
2002-11-20
2023-09-20
Magnesium, water, filtered, milligrams per liter
00927
121
2002-11-20
2023-09-20
Magnesium, water, unfiltered, recoverable, milligrams per liter
00929
49
2002-11-20
2023-09-20
Sodium, water, unfiltered, recoverable, milligrams per liter
00937
49
2002-11-20
2023-09-20
Potassium, water, unfiltered, recoverable, milligrams per liter
00945
5
2002-11-20
2023-09-20
Sulfate, water, filtered, milligrams per liter
00946
123
2002-11-20
2023-09-20
Sulfate, water, unfiltered, milligrams per liter
00951
2
2002-11-20
2023-09-20
Fluoride, water, unfiltered, milligrams per liter
01000
3
2002-11-20
2023-09-20
Arsenic, water, filtered, micrograms per liter
01007
4
2002-11-20
2023-09-20
Barium, water, unfiltered, recoverable, micrograms per liter
01022
2
2002-11-20
2023-09-20
Boron, water, unfiltered, recoverable, micrograms per liter
01025
3
2002-11-20
2023-09-20
Cadmium, water, filtered, micrograms per liter
01040
120
2002-11-20
2023-09-20
Copper, water, filtered, micrograms per liter
01042
122
2002-11-20
2023-09-20
Copper, water, unfiltered, recoverable, micrograms per liter
01045
122
2002-11-20
2023-09-20
Iron, water, unfiltered, recoverable, micrograms per liter
01046
120
2002-11-20
2023-09-20
Iron, water, filtered, micrograms per liter
01049
120
2002-11-20
2023-09-20
Lead, water, filtered, micrograms per liter
01051
123
2002-11-20
2023-09-20
Lead, water, unfiltered, recoverable, micrograms per liter
01055
121
2002-11-20
2023-09-20
Manganese, water, unfiltered, recoverable, micrograms per liter
01056
118
2002-11-20
2023-09-20
Manganese, water, filtered, micrograms per liter
01065
120
2002-11-20
2023-09-20
Nickel, water, filtered, micrograms per liter
01067
123
2002-11-20
2023-09-20
Nickel, water, unfiltered, recoverable, micrograms per liter
01082
2
2002-11-20
2023-09-20
Strontium, water, unfiltered, recoverable, micrograms per liter
01090
113
2002-11-20
2023-09-20
Zinc, water, filtered, micrograms per liter
01092
115
2002-11-20
2023-09-20
Zinc, water, unfiltered, recoverable, micrograms per liter
01105
122
2002-11-20
2023-09-20
Aluminum, water, unfiltered, recoverable, micrograms per liter
01106
109
2002-11-20
2023-09-20
Aluminum, water, filtered, micrograms per liter
01130
44
2002-11-20
2023-09-20
Lithium, water, filtered, micrograms per liter
01132
44
2002-11-20
2023-09-20
Lithium, water, unfiltered, recoverable, micrograms per liter
01147
2
2002-11-20
2023-09-20
Selenium, water, unfiltered, micrograms per liter
04096
10
2002-11-20
2023-09-20
Aluminum, water, filtered (0.1 micron filter), micrograms per liter
30209
123
2002-11-20
2023-09-20
Discharge, instantaneous, cubic meters per second
31616
1
2002-11-20
2023-09-20
Fecal coliforms, M-FC MF (0.45 micron) method, water, colony forming units per 100 milliliters
31648
7
2002-11-20
2023-09-20
Escherichia coli, m-TEC MF method, water, colonies per 100 milliliters
31649
7
2002-11-20
2023-09-20
Enterococci, m-E MF method, water, colony forming units per 100 milliliters
32730
1
2002-11-20
2023-09-20
Phenolic compounds, water, unfiltered, recoverable, micrograms per liter
50280
65
2002-11-20
2023-09-20
Site visit purpose, code
50305
8
2002-11-20
2023-09-20
Caffeine, water, filtered, recoverable, micrograms per liter
53961
1
2002-11-20
2023-09-20
N-Methylperfluorooctanesulfonamidoacetate (N-MeFOSAA), linear and branched, water, unfiltered, recoverable, nanograms per liter
53962
1
2002-11-20
2023-09-20
N-Ethylperfluorooctanesulfonamidoacetate (N-EtFOSAA), linear and branched, water, unfiltered, recoverable, nanograms per liter
54091
1
2002-11-20
2023-09-20
11-Chloroeicosafluoro-3-oxaundecane-1-sulfonate (11Cl-PF3OUdS), linear and branched, water, unfiltered, recoverable, nanograms per liter
54092
1
2002-11-20
2023-09-20
1H,1H,2H,2H-Perfluorohexane sulfonate (4:2 FTS), linear and branched, water, unfiltered, recoverable, nanograms per liter
54093
1
2002-11-20
2023-09-20
1H,1H,2H,2H-Perfluorooctane sulfonate (6:2 FTS), linear and branched, water, unfiltered, recoverable, nanograms per liter
54094
1
2002-11-20
2023-09-20
1H,1H,2H,2H-Perfluorodecane sulfonate (8:2 FTS), linear and branched, water, unfiltered, recoverable, nanograms per liter
54095
1
2002-11-20
2023-09-20
9-Chlorohexadecafluoro-3-oxanonane-1-sulfonate (9Cl-PF3ONS), linear and branched, water, unfiltered, recoverable, nanograms per liter
54096
1
2002-11-20
2023-09-20
4,8-Dioxa-3H-perfluorononanoate (DONA), linear and branched, water, unfiltered, recoverable, nanograms per liter
54097
1
2002-11-20
2023-09-20
Perfluoro-2-propoxypropanoate (HFPO-DA), linear and branched, water, unfiltered, recoverable, nanograms per liter
54098
1
2002-11-20
2023-09-20
N-Ethylperfluorooctanesulfonamide (N-EtFOSA), linear and branched, water, unfiltered, recoverable, nanograms per liter
54100
1
2002-11-20
2023-09-20
N-Ethylperfluorooctanesulfonamidoethanol (N-EtFOSE), linear and branched, water, unfiltered, recoverable, nanograms per liter
54101
1
2002-11-20
2023-09-20
N-Methylperfluorooctanesulfonamide (N-MeFOSA), linear and branched, water, unfiltered, recoverable, nanograms per liter
54103
1
2002-11-20
2023-09-20
N-Methylperfluorooctanesulfonamidoethanol (N-MeFOSE), linear and branched, water, unfiltered, recoverable, nanograms per liter
54104
1
2002-11-20
2023-09-20
Perfluorobutanoate (PFBA), linear and branched, water, unfiltered, recoverable, nanograms per liter
54105
1
2002-11-20
2023-09-20
Perfluorobutane sulfonate (PFBS), linear and branched, water, unfiltered, recoverable, nanograms per liter
54106
1
2002-11-20
2023-09-20
Perfluorodecanoate (PFDA), linear and branched, water, unfiltered, recoverable, nanograms per liter
54107
1
2002-11-20
2023-09-20
Perfluorododecanoate (PFDoDA), linear and branched, water, unfiltered, recoverable, nanograms per liter
54108
1
2002-11-20
2023-09-20
Perfluorododecane sulfonate (PFDoDS), linear and branched, water, unfiltered, recoverable, nanograms per liter
54109
1
2002-11-20
2023-09-20
Perfluorodecane sulfonate (PFDS), linear and branched, water, unfiltered, recoverable, nanograms per liter
54110
1
2002-11-20
2023-09-20
Perfluoroheptanoate (PFHpA), linear and branched, water, unfiltered, recoverable, nanograms per liter
54111
1
2002-11-20
2023-09-20
Perfluoroheptane sulfonate (PFHpS), linear and branched, water, unfiltered, recoverable, nanograms per liter
54112
1
2002-11-20
2023-09-20
Perfluorohexanoate (PFHxA), linear and branched, water, unfiltered, recoverable, nanograms per liter
54113
1
2002-11-20
2023-09-20
Perfluorohexane sulfonate (PFHxS), linear and branched, water, unfiltered, recoverable, nanograms per liter
54114
1
2002-11-20
2023-09-20
Perfluorononanoate (PFNA), linear and branched, water, unfiltered, recoverable, nanograms per liter
54115
1
2002-11-20
2023-09-20
Perfluorononane sulfonate (PFNS), linear and branched, water, unfiltered, recoverable, nanograms per liter
54116
1
2002-11-20
2023-09-20
Perfluorooctanoate (PFOA), linear and branched, water, unfiltered, recoverable, nanograms per liter
54117
1
2002-11-20
2023-09-20
Perfluorooctane sulfonate (PFOS), linear and branched, water, unfiltered, recoverable, nanograms per liter
54118
1
2002-11-20
2023-09-20
Perfluorooctanesulfonamide (PFOSA, also called FOSA), linear and branched, water, unfiltered, recoverable, nanograms per liter
54119
1
2002-11-20
2023-09-20
Perfluoropentanoate (PFPeA), linear and branched, water, unfiltered, recoverable, nanograms per liter
54120
1
2002-11-20
2023-09-20
Perfluoropentane sulfonate (PFPeS), linear and branched, water, unfiltered, recoverable, nanograms per liter
54121
1
2002-11-20
2023-09-20
Perfluorotetradecanoate (PFTeDA), linear and branched, water, unfiltered, recoverable, nanograms per liter
54122
1
2002-11-20
2023-09-20
Perfluorotridecanoate (PFTrDA), linear and branched, water, unfiltered, recoverable, nanograms per liter
54123
1
2002-11-20
2023-09-20
Perfluoroundecanoate (PFUnDA), linear and branched, water, unfiltered, recoverable, nanograms per liter
54124
1
2002-11-20
2023-09-20
Perfluorobutanoate (PFBA) plus total oxidizable precursors (TOP), water, unfiltered, recoverable, nanograms per liter
54125
1
2002-11-20
2023-09-20
Perfluorobutane sulfonate (PFBS) plus total oxidizable precursors (TOP), water, unfiltered, recoverable, nanograms per liter
54126
1
2002-11-20
2023-09-20
Perfluorodecanoate (PFDA) plus total oxidizable precursors (TOP), water, unfiltered, recoverable, nanograms per liter
54127
1
2002-11-20
2023-09-20
Perfluorododecanoate (PFDoDA) plus total oxidizable precursors (TOP), water, unfiltered, recoverable, nanograms per liter
54128
1
2002-11-20
2023-09-20
Perfluorododecane sulfonate (PFDoDS) plus total oxidizable precursors (TOP), water, unfiltered, recoverable, nanograms per liter
54129
1
2002-11-20
2023-09-20
Perfluorodecane sulfonate (PFDS) plus total oxidizable precursors (TOP), water, unfiltered, recoverable, nanograms per liter
54130
1
2002-11-20
2023-09-20
Perfluoroheptanoate (PFHpA) plus total oxidizable precursors (TOP), water, unfiltered, recoverable, nanograms per liter
54131
1
2002-11-20
2023-09-20
Perfluoroheptane sulfonate (PFHpS) plus total oxidizable precursors (TOP), water, unfiltered, recoverable, nanograms per liter
54132
1
2002-11-20
2023-09-20
Perfluorohexanoate (PFHxA) plus total oxidizable precursors (TOP), water, unfiltered, recoverable, nanograms per liter
54133
1
2002-11-20
2023-09-20
Perfluorohexane sulfonate (PFHxS) plus total oxidizable precursors (TOP), water, unfiltered, recoverable, nanograms per liter
54134
1
2002-11-20
2023-09-20
Perfluorononanoate (PFNA) plus total oxidizable precursors (TOP), water, unfiltered, recoverable, nanograms per liter
54135
1
2002-11-20
2023-09-20
Perfluorononane sulfonate (PFNS) plus total oxidizable precursors (TOP), water, unfiltered, recoverable, nanograms per liter
54136
1
2002-11-20
2023-09-20
Perfluorooctanoate (PFOA) plus total oxidizable precursors (TOP), water, unfiltered, recoverable, nanograms per liter
54137
1
2002-11-20
2023-09-20
Perfluorooctane sulfonate (PFOS) plus total oxidizable precursors (TOP), water, unfiltered, recoverable, nanograms per liter
54138
1
2002-11-20
2023-09-20
Perfluoropentanoate (PFPeA) plus total oxidizable precursors (TOP), water, unfiltered, recoverable, nanograms per liter
54139
1
2002-11-20
2023-09-20
Perfluoropentane sulfonate (PFPeS) plus total oxidizable precursors (TOP), water, unfiltered, recoverable, nanograms per liter
54140
1
2002-11-20
2023-09-20
Perfluorotetradecanoate (PFTeDA) plus total oxidizable precursors (TOP), water, unfiltered, recoverable, nanograms per liter
54141
1
2002-11-20
2023-09-20
Perfluorotridecanoate (PFTrDA) plus total oxidizable precursors (TOP), water, unfiltered, recoverable, nanograms per liter
54142
1
2002-11-20
2023-09-20
Perfluoroundecanoate (PFUnDA) plus total oxidizable precursors (TOP), water, unfiltered, recoverable, nanograms per liter
61744
11
2002-11-20
2023-09-20
Chlortetracycline, water, filtered, recoverable, micrograms per liter
61759
11
2002-11-20
2023-09-20
Oxytetracycline, water, filtered, recoverable, micrograms per liter
61762
11
2002-11-20
2023-09-20
Sulfamethazine, water, filtered, recoverable, micrograms per liter
62000
8
2002-11-20
2023-09-20
Acetaminophen, water, filtered, recoverable, micrograms per liter
62003
8
2002-11-20
2023-09-20
Codeine, water, filtered, recoverable, micrograms per liter
62004
8
2002-11-20
2023-09-20
Dehydronifedipine, water, filtered, recoverable, micrograms per liter
62005
8
2002-11-20
2023-09-20
Cotinine, water, filtered, recoverable, micrograms per liter
62008
8
2002-11-20
2023-09-20
Diltiazem, water, filtered, recoverable, micrograms per liter
62014
11
2002-11-20
2023-09-20
Ibuprofen, water, filtered, recoverable, micrograms per liter
62020
8
2002-11-20
2023-09-20
Albuterol, water, filtered, recoverable, micrograms per liter
62021
8
2002-11-20
2023-09-20
Sulfamethoxazole, water, filtered, recoverable, micrograms per liter
62023
19
2002-11-20
2023-09-20
Trimethoprim, water, filtered, recoverable, micrograms per liter
62024
8
2002-11-20
2023-09-20
Warfarin, water, filtered, recoverable, micrograms per liter
62030
8
2002-11-20
2023-09-20
1,7-Dimethylxanthine, water, filtered, recoverable, micrograms per liter
62694
11
2002-11-20
2023-09-20
Doxycycline, water, filtered (0.7 micron glass fiber filter), recoverable, micrograms per liter
62757
11
2002-11-20
2023-09-20
Norfloxacin, water, filtered (0.7 micron glass fiber filter), recoverable, micrograms per liter
62771
11
2002-11-20
2023-09-20
Sarafloxacin, water, filtered (0.7 micron glass fiber filter), recoverable, micrograms per liter
62774
11
2002-11-20
2023-09-20
Sulfachlorpyridazine, water, filtered (0.7 micron glass fiber filter), recoverable, micrograms per liter
62775
11
2002-11-20
2023-09-20
Sulfamethoxazole, water, filtered (0.7 micron glass fiber filter), recoverable, micrograms per liter
62776
11
2002-11-20
2023-09-20
Sulfadimethoxine, water, filtered (0.7 micron glass fiber filter), recoverable, micrograms per liter
62778
11
2002-11-20
2023-09-20
Sulfathiazole, water, filtered (0.7 micron glass fiber filter), recoverable, micrograms per liter
62781
11
2002-11-20
2023-09-20
Tetracycline, water, filtered (0.7 micron glass fiber filter), recoverable, micrograms per liter
62792
11
2002-11-20
2023-09-20
Azithromycin, water, filtered, recoverable, micrograms per liter
62793
19
2002-11-20
2023-09-20
Carbamazepine, water, filtered, recoverable, micrograms per liter
62796
8
2002-11-20
2023-09-20
Diphenhydramine, water, filtered, recoverable, micrograms per liter
62797
11
2002-11-20
2023-09-20
Erythromycin, water, filtered, recoverable, micrograms per liter
62801
8
2002-11-20
2023-09-20
Thiabendazole, water, filtered, recoverable, micrograms per liter
62855
11
2002-11-20
2023-09-20
Total nitrogen [nitrate + nitrite + ammonia + organic-N], water, unfiltered, analytically determined, milligrams per liter
62894
11
2002-11-20
2023-09-20
Lincomycin, water, filtered, recoverable, micrograms per liter
62895
11
2002-11-20
2023-09-20
Roxithromycin, water, filtered, recoverable, micrograms per liter
62896
11
2002-11-20
2023-09-20
Tylosin, water, filtered, recoverable, micrograms per liter
62897
11
2002-11-20
2023-09-20
Virginiamycin, water, filtered, recoverable, micrograms per liter
62898
11
2002-11-20
2023-09-20
Ciprofloxacin, water, filtered, recoverable, micrograms per liter
62899
11
2002-11-20
2023-09-20
Ofloxacin, water, filtered, recoverable, micrograms per liter
62900
11
2002-11-20
2023-09-20
Lomefloxacin, water, filtered, recoverable, micrograms per liter
62962
11
2002-11-20
2023-09-20
Ormetoprim, water, filtered, recoverable, micrograms per liter
62963
11
2002-11-20
2023-09-20
Sulfadiazine, water, filtered, recoverable, micrograms per liter
63674
11
2002-11-20
2023-09-20
Anhydroerthromycin, water, filtered, recoverable, micrograms per liter
63727
11
2002-11-20
2023-09-20
4-Epitetracycline hydrochloride, water, filtered, recoverable, micrograms per liter
63729
11
2002-11-20
2023-09-20
4-Epioxytetracycline, water, filtered, recoverable, micrograms per liter
63731
11
2002-11-20
2023-09-20
4-Epichlortetracycline hydrochloride, water, filtered, recoverable, micrograms per liter
64047
11
2002-11-20
2023-09-20
Isoepichlortetracycline, water, filtered, recoverable, micrograms per liter
64175
11
2002-11-20
2023-09-20
Isochlortetracycline, water, filtered, recoverable, micrograms per liter
65194
11
2002-11-20
2023-09-20
Chloramphenicol, water, filtered, recoverable, micrograms per liter
66495
11
2002-11-20
2023-09-20
Enrofloxacin, water, filtered, recoverable, micrograms per liter
70300
74
2002-11-20
2023-09-20
Dissolved solids dried at 180 degrees Celsius, water, filtered, milligrams per liter
70302
69
2002-11-20
2023-09-20
Dissolved solids, water, short tons per day
70303
74
2002-11-20
2023-09-20
Dissolved solids, water, filtered, short tons per acre-foot
70507
121
2002-11-20
2023-09-20
Orthophosphate, water, unfiltered, milligrams per liter as phosphorus
70508
108
2002-11-20
2023-09-20
Acidity, water, unfiltered, heated, milligrams per liter as calcium carbonate
71845
123
2002-11-20
2023-09-20
Ammonia (NH3 + NH4+), water, unfiltered, milligrams per liter as NH4
71846
1
2002-11-20
2023-09-20
Ammonia (NH3 + NH4+), water, filtered, milligrams per liter as NH4
71870
50
2002-11-20
2023-09-20
Bromide, water, filtered, milligrams per liter
71999
1
2002-11-20
2023-09-20
Sample purpose, code
72176
10
2002-11-20
2023-09-20
Temperature of sensor, degrees Celsius
82398
113
2002-11-20
2023-09-20
Sampling method, code
82550
4
2002-11-20
2023-09-20
Osmotic pressure, water, unfiltered, milliosmoles per kilogram
84164
1
2002-11-20
2023-09-20
Sampler type, code
84171
65
2002-11-20
2023-09-20
Sample splitter type, field, code
90095
118
2002-11-20
2023-09-20
Specific conductance, water, unfiltered, laboratory, microsiemens per centimeter at 25 degrees Celsius
90797
8
2002-11-20
2023-09-20
Carbamazepine-d10, surrogate, pharmaceutical method, water, filtered, percent recovery
91000
11
2002-11-20
2023-09-20
Bromide, water, filtered, micrograms per liter
99220
87
2002-11-20
2023-09-20
Chloride, water, unfiltered, milligrams per liter
99571
8
2002-11-20
2023-09-20
Ethyl nicotinate-d4, surrogate, water, filtered, percent recovery
99572
8
2002-11-20
2023-09-20
Sample volume, pharmaceutical method, water, filtered, milliliters
99597
10
2002-11-20
2023-09-20
Giardia, water, method 1623, cysts per 10 liters
99599
10
2002-11-20
2023-09-20
Cryptosporidium, water, method 1623, oocysts per 10 liters