Brief Description

Drinking water and source water test that enumerates aerobic, heterotrophic bacteria using a plate count method (HPC).

Laboratory Unit

Environmental Bacteriology

Methodology

Standard Method 9215B Pour Plate using R2A agar.

Specimen Collection

Click here for sampling instructions. Minimum volume 100 ml.

Storage/Transport

Sterile, disposable 120 ml plastic bottle containing sodium thiosulfate. Must use sample kit provided by MSPHL.

Ship to MSPHL immediately. Must be received in lab within 30 hours (public drinking water) or 48 hours (private wells) of sampling. Source water samples must be received in lab within 8 hours of sampling. May be stored in refrigerator conditions temporarily prior to shipping. Use of a cooler and ice packs in the field is recommended..

Acceptable Specimen Type(s)

Potable water from public water supply or private well. Public supply source water samples (surface water and ground water sources).

Test Request Form(s)

Heterotrophic Plate Count (HPC) testing is done by special request only. Sample submission forms must be marked "HPC" in the upper right section of the form. Public water samples must be submitted by an official of the public supply following a DNR approved sampling plan. Use the Public Water Sample Form LAB 10B.

The general public may submit private well samples. Test results are considered "Unofficial" and are for informational purposes only. Use the Unofficial Private Water Sample Form LAB 10C.

Private well samples to be used for "Official" purposes, including real estate transactions and health related inspections, must be submitted by an official of the state or local health agency, or a state licensed sample collector/well inspector. Use the Official Private Water Sample Form LAB 10G.

Possible Results

<1 through >5700 CFU/ml Heterotrophic Bacteria (CFU - Colony Forming Unit)

Unacceptable Conditions

Transit time exceeded
No date/time collected
No sample identification
Sample form incomplete
Quantity not sufficient (100 ml)
Sample leaked in transit
Sample frozen
Presence of disinfectant
Unapproved container.

Interfering Substances

Disinfectants
Hydrocarbons
Cleansers

Result Reported

Results are reported to DNR (public water samples) or to the submitter (private water samples) within 48-72 hours of sample receipt in lab.

Fees

Private well samples are charged a $10 handling fee. Invoice will be sent with sample results. There is no charge for public water samples submitted by public supplies for their monthly EPA/DNR Safe Drinking Water Act compliance testing.

CPT Codes

N/A

LOINC/SNOMED Codes

N/A

Additional Information

HPC testing is done by special request only. Sample submission forms must be marked "HPC" in the upper right section of the form. Public water samples must be submitted by an official of the public supply following a DNR approved sampling plan. Use the Public Water Sample Form LAB 10B.

The general public may submit private well samples. Test results are considered "Unofficial" and are for informational purposes only. Use the Unofficial Private Water Sample Form LAB 10C.

Private well samples to be used for "Official" purposes, including real estate transactions and health related inspections, must be submitted by an official of the state or local health agency, or a state licensed sample collector/well inspector. Use the Official Private Water Sample Form LAB 10G.