Classification of Water Samples

This is in response to your letter of December 14, 1999, and subsequent telephone conversations with Michael Johnsen, of my staff, concerning the classification of water samples under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). You provided the following table of water samples regularly shipped by the USGS and its clients:

Analysis Type Water Sample Preparation Preservative Concentration (% by weight)
Oil and Grease 2 ml H2SO4(18M) / L sample 0.35
Phenol 1 ml H2SO4(18M) / 500 ml sample 0.35
Nutrient 1 ml H2SO4(1:7) / 125 ml sample 0.20
Cyanide 5 ml NaOH (5N) / 240 ml sample 0.42
Volatile Organics 0.1 ml H.L. (12M) / 40 ml sample 0.11
Metals (RA/FA) 2 ml HNO3 (7.6) / 250 ml sample 0.40
Mercury Sample 10 ml HNO3 (15.8M) /240 ml sample 4.15
0.35 g K2Cr2O7 0.014

In addition, you included a letter issued by this office on December 13, 1993, which listed several corrosive materials that were so dilute they are excepted from the HMR. According to our letter, H2S04 (sulfuric acid) in water solutions at concentrations of 0.35% by weight or less are excepted from the HMR.

From the information you have provided, we have made the following recommendations for classifying these materials:

• Based on this exception, three of the Analysis Types in question which contain H2SO4 (Analysis Type: Oil and Grease; Phenol; and Nutrient) are not regulated by the HMR.

• Three water samples (Analysis Type: Cyanide; Volatile Organics; and Metals (RA/FA)) should be tested to determine if they meet the definition for corrosive material. It is the opinion of this Office that these three samples are not corrosive to skin. However, these preparations may be corrosive to metal (steel and/or aluminum).

• The sample containing HNO3, (nitric acid) and K2Cr2O7, (potassium dichromate) (Analysis type: Mercury Sample) is a corrosive material. Tests for skin corrosion should be conducted to determine the packing group.