^[1] Polyethylene (P) or Glass (G).

^[2]Sample preservation should be performed immediately upon sample collection.  For composite chemical samples each aliquot should be preserved at the time of collection.  When use of an automated sampler makes it impossible to preserve each aliquot, the chemical samples may be preserved by maintaining at 4 ºC until compositing and sample splitting is completed.

^[3] When any sample is to be shipped by common carrier or sent through the US Mails, it must comply with the Department of Transportation Hazardous Materials Regulations (49 CFR 172).  The person offering such material for transportation is responsible for ensuring such compliance.  For the preservation requirements of the Table, the Office of Hazardous Materials, Materials Transportation Bureau, Department of Transportation has determined that the Hazardous Materials Regulations do not apply to the following materials: Hydrochloric acid (HCl) in water solutions at concentrations of 0.04% by weight or less (pH about 1.96 SU or greater);  Nitric acid (HNO₃) in water solutions of 0.15% by weight or less (pH about 1.62 SU or greater); Sulfuric acid (H₂SO₄ ) in water solutions at concentrations of 0.35% by weight or less (pH about 1.15 SU or greater); and Sodium Hydroxide (NaOH) in water solutions of 0.080 % by  weight or less (pH about 12.30 or less).

^[4]Samples should be analyzed as soon as possible after collection.  The times listed are the maximum times that samples may be held before analysis and still be considered valid.  Samples my be held for longer periods only if the permittee, or monitoring laboratory, has data on file to show that the specific types of samples under study are stable for longer time, and has received a variance from the Regional Administrator under 40 CFR 136.3(e).  Some samples may not be stable for the maximum time period given in the Table.  A permittee, or monitoring laboratory, is obligated to hold the sample for a shorter time if knowledge exists to show that this is necessary to maintain sample stability.  See 40 CFR 136.3(e) for details.

^[5] Should only be used in the presence of residual chlorine.

^[6]Maximum holding time is 24 hours when sulfide is present.  Optionally, all  samples may be tested with lead acetate paper before pH adjustments in order to determine if sulfide is present.  If sulfide is present, it can be removed by the addition of cadmium nitrate powder until a negative spot test is obtained.  The sample is filtered and then NaOH is added to pH of 12.

^[7]Polyethylene (P) or Glass (G).

^[8]Sample preservation should be performed immediately upon sample collection.  For composite chemical samples each aliquot should be preserved at the time of collection.  When use of an automated sampler makes it impossible to preserve each aliquot, the chemical samples may be preserved by maintaining at 4 ºC until compositing and sample splitting is completed.

^[9]When any sample is to be shipped by common carrier or sent through the US Mails, it must comply with the Department of Transportation Hazardous Materials Regulations (49 CFR 172).  The person offering such material for transportation is responsible for ensuring such compliance.  For the preservation requirements of the Table, the Office of Hazardous Materials, Materials Transportation Bureau, Department of Transportation has determined that the Hazardous Materials Regulations do not apply to the following materials: Hydrochloric acid (HCl) in water solutions at concentrations of 0.04% by weight or less (pH about 1.96 SU or greater);  Nitric acid (HNO₃) in water solutions of 0.15% by weight or less (pH about 1.62 SU or greater); Sulfuric acid (H₂SO₄ ) in water solutions at concentrations of 0.35% by weight or less (pH about 1.15 SU or greater); and Sodium Hydroxide (NaOH) in water solutions of 0.080 % by  weight or less (pH about 12.30 or less).

^[10]Samples should be analyzed as soon as possible after collection.  The times listed are the maximum times that samples may be held before analysis and still be considered valid.  Samples my be held for longer periods only if the permittee, or monitoring laboratory, has data on file to show that the specific types of samples under study are stable for longer time, and has received a variance from the Regional Administrator under 40 CFR 136.3(e).  Some samples may not be stable for the maximum time period given in the Table.  A permittee, or monitoring laboratory, is obligated to hold the sample for a shorter time if knowledge exists to show that this is necessary to maintain sample stability.  See 40 CFR 136.3(e) for details.

^[11]Samples should be filtered immediately on-site before adding preservative for dissolved metals.

^[12]in situ means that the probe is inserted into the actual mass to be sampled, recording the readout including profiles.

^[13]Polyethylene (P) or Glass (G).

^[14]Sample preservation should be performed immediately upon sample collection.  For composite chemical samples each aliquot should be preserved at the time of collection.  When use of an automated sampler makes it impossible to preserve each aliquot, the chemical samples may be preserved by maintaining at 4 ºC until compositing and sample splitting is completed.

^[15]When any sample is to be shipped by common carrier or sent through the US Mails, it must comply with the Department of Transportation Hazardous Materials Regulations (49 CFR 172).  The person offering such material for transportation is responsible for ensuring such compliance.  For the preservation requirements of the Table, the Office of Hazardous Materials, Materials Transportation Bureau, Department of Transportation has determined that the Hazardous Materials Regulations do not apply to the following materials: Hydrochloric acid (HCl) in water solutions at concentrations of 0.04% by weight or less (pH about 1.96 SU or greater);  Nitric acid (HNO₃) in water solutions of 0.15% by weight or less (pH about 1.62 SU or greater); Sulfuric acid (H₂SO₄ ) in water solutions at concentrations of 0.35% by weight or less (pH about 1.15 SU or greater); and Sodium Hydroxide (NaOH) in water solutions of 0.080 % by  weight or less (pH about 12.30 or less).

^[16]Samples should be analyzed as soon as possible after collection.  The times listed are the maximum times that samples may be held before analysis and still be considered valid.  Samples my be held for longer periods only if the permittee, or monitoring laboratory, has data on file to show that the specific types of samples under study are stable for longer time, and has received a variance from the Regional Administrator under 40 CFR 136.3(e).  Some samples may not be stable for the maximum time period given in the Table.  A permittee, or monitoring laboratory, is obligated to hold the sample for a shorter time if knowledge exists to show that this is necessary to maintain sample stability.  See 40 CFR 136.3(e) for details.

^[17] Polyethylene (P) or Glass (G).

^[18]Sample preservation should be performed immediately upon sample collection.  For composite chemical samples each aliquot should be preserved at the time of collection.  When use of an automated sampler makes it impossible to preserve each aliquot, the chemical samples may be preserved by maintaining at 4 ºC until compositing and sample splitting is completed.

^[19] When any sample is to be shipped by common carrier or sent through the US Mails, it must comply with the Department of Transportation Hazardous Materials Regulations (49 CFR 172).  The person offering such material for transportation is responsible for ensuring such compliance.  For the preservation requirements of the Table, the Office of Hazardous Materials, Materials Transportation Bureau, Department of Transportation has determined that the Hazardous Materials Regulations do not apply to the following materials: Hydrochloric acid (HCl) in water solutions at concentrations of 0.04% by weight or less (pH about 1.96 SU or greater);  Nitric acid (HNO₃) in water solutions of 0.15% by weight or less (pH about 1.62 SU or greater); Sulfuric acid (H₂SO₄ ) in water solutions at concentrations of 0.35% by weight or less (pH about 1.15 SU or greater); and Sodium Hydroxide (NaOH) in water solutions of 0.080 % by  weight or less (pH about 12.30 or less).

^[20]Samples should be analyzed as soon as possible after collection.  The times listed are the maximum times that samples may be held before analysis and still be considered valid.  Samples my be held for longer periods only if the permittee, or monitoring laboratory, has data on file to show that the specific types of samples under study are stable for longer time, and has received a variance from the Regional Administrator under 40 CFR 136.3(e).  Some samples may not be stable for the maximum time period given in the Table.  A permittee, or monitoring laboratory, is obligated to hold the sample for a shorter time if knowledge exists to show that this is necessary to maintain sample stability.  See 40 CFR 136.3(e) for details.

^[21] Should only be used in the presence of residual chlorine.

^[22]Maximum holding time is 24 hours when sulfide is present.  Optionally, all  samples may be tested with lead acetate paper before pH adjustments in order to determine if sulfide is present.  If sulfide is present, it can be removed by the addition of cadmium nitrate powder until a negative spot test is obtained.  The sample is filtered and then NaOH is added to pH of 12.

^[23]Polyethylene (P) or Glass (G).

^[24]Sample preservation should be performed immediately upon sample collection.  For composite chemical samples each aliquot should be preserved at the time of collection.  When use of an automated sampler makes it impossible to preserve each aliquot, the chemical samples may be preserved by maintaining at 4 ºC until compositing and sample splitting is completed.

^[25]When any sample is to be shipped by common carrier or sent through the US Mails, it must comply with the Department of Transportation Hazardous Materials Regulations (49 CFR 172).  The person offering such material for transportation is responsible for ensuring such compliance.  For the preservation requirements of the Table, the Office of Hazardous Materials, Materials Transportation Bureau, Department of Transportation has determined that the Hazardous Materials Regulations do not apply to the following materials: Hydrochloric acid (HCl) in water solutions at concentrations of 0.04% by weight or less (pH about 1.96 SU or greater);  Nitric acid (HNO₃) in water solutions of 0.15% by weight or less (pH about 1.62 SU or greater); Sulfuric acid (H₂SO₄ ) in water solutions at concentrations of 0.35% by weight or less (pH about 1.15 SU or greater); and Sodium Hydroxide (NaOH) in water solutions of 0.080 % by  weight or less (pH about 12.30 or less).

^[26]Samples should be analyzed as soon as possible after collection.  The times listed are the maximum times that samples may be held before analysis and still be considered valid.  Samples my be held for longer periods only if the permittee, or monitoring laboratory, has data on file to show that the specific types of samples under study are stable for longer time, and has received a variance from the Regional Administrator under 40 CFR 136.3(e).  Some samples may not be stable for the maximum time period given in the Table.  A permittee, or monitoring laboratory, is obligated to hold the sample for a shorter time if knowledge exists to show that this is necessary to maintain sample stability.  See 40 CFR 136.3(e) for details.

^[27]Samples should be filtered immediately on-site before adding preservative for dissolved metals.

^[28]in situ means that the probe is inserted into the actual mass to be sampled, recording the readout including profiles.

^[29]Polyethylene (P) or Glass (G).

^[30]Sample preservation should be performed immediately upon sample collection.  For composite chemical samples each aliquot should be preserved at the time of collection.  When use of an automated sampler makes it impossible to preserve each aliquot, the chemical samples may be preserved by maintaining at 4 ºC until compositing and sample splitting is completed.

^[31]When any sample is to be shipped by common carrier or sent through the US Mails, it must comply with the Department of Transportation Hazardous Materials Regulations (49 CFR 172).  The person offering such material for transportation is responsible for ensuring such compliance.  For the preservation requirements of the Table, the Office of Hazardous Materials, Materials Transportation Bureau, Department of Transportation has determined that the Hazardous Materials Regulations do not apply to the following materials: Hydrochloric acid (HCl) in water solutions at concentrations of 0.04% by weight or less (pH about 1.96 SU or greater);  Nitric acid (HNO₃) in water solutions of 0.15% by weight or less (pH about 1.62 SU or greater); Sulfuric acid (H₂SO₄ ) in water solutions at concentrations of 0.35% by weight or less (pH about 1.15 SU or greater); and Sodium Hydroxide (NaOH) in water solutions of 0.080 % by  weight or less (pH about 12.30 or less).

^[32]Samples should be analyzed as soon as possible after collection.  The times listed are the maximum times that samples may be held before analysis and still be considered valid.  Samples my be held for longer periods only if the permittee, or monitoring laboratory, has data on file to show that the specific types of samples under study are stable for longer time, and has received a variance from the Regional Administrator under 40 CFR 136.3(e).  Some samples may not be stable for the maximum time period given in the Table.  A permittee, or monitoring laboratory, is obligated to hold the sample for a shorter time if knowledge exists to show that this is necessary to maintain sample stability.  See 40 CFR 136.3(e) for details.