Ontario Ministry of the Environment, Conservation and Parks (MECP)
Drinking Water Surveillance Program (DWSP)

USER GUIDE FOR UNDERSTANDING DRINKING WATER SURVEILLANCE PROGRAM DATA


TABLE: COLUMN HEADERS 

Year: 				Sample year.
Sample Program: 		The Drinking Water Surveillance Program has two types of sampling programs - routine and special studies. Routine samples are collected at all drinking water systems at regular intervals year-round and are analyzed for an extensive and varied list of parameters. Special study samples are collected at select drinking water systems, sometimes seasonally, with a focus on one class of parameters.
Drinking Water System Name:	The drinking water system name registered with the Ministry of the Environment, Conservation and Parks.
Drinking Water System #:	A unique 9-digit ID number assigned to each drinking water system by the Ministry of the Environment, Conservation and Parks.
Sample Type: 			There are three sample types: raw water, treated water and distribution system water. Raw water is untreated source water entering the water treatment facility. Treated water has been through all treatment processes and is on its way out of the water treatment facility to consumers. Raw water and treated water samples are collected inside water treatment facilities. Distribution system water is the water coming out of consumers' taps. Raw water samples from surface water treatment plants occasionally contain chlorine due to zebra mussel chlorination at the intake pipe mouth (to prevent intake pipe clogging by mussels).
Sample Location: 		The precise location in the water treatment facility or in the distribution system where a sample is collected.
Station #: 			The unique 13-digit ID for a sample location. Station numbers are internal to the Drinking Water Surveillance Program database.
Sample Condition: 		Applies to distribution system samples. 'Free flowing' means the tap was adequately flushed before sampling. Drinking Water Surveillance Program distribution system samples are always free flowing.
Sample Date: 			The date the sample was collected. The date format is YYYY-MM-DD (2014-06-23).
Sample Time: 			The time the sample was collected.
Parameter Group: 		In the Drinking Water Surveillance Program database, each parameter is assigned to a parameter group. For example, iron is assigned to the Metals parameter group. The parameter groups are internal to the DWSP database, and are useful for classification and reporting purposes.
Parameter: 			The chemical, radionuclide or physical attribute measured in drinking water. Chromium (a metal), atrazine (a pesticide), and temperature (a physical attribute) are examples of parameters.
Analysis Method: 		The Ministry lab's reference number for an analytical method.
Detection Limit (DL): 		The lowest concentration/level a laboratory method can confidently detect a chemical. Detection limits vary from method to method, and from parameter to parameter.
Detection Limit Unit: 		The unit of measurement used to report detection limits.  
Result:				The parameter concentration reported by the lab. If a result is reported as <DL, the compound was not detected at the detection limit level.
Result Unit:	 		The unit of measurement used to report results.  
Result Qualifier: 		Some results are accompanied by a qualifier. Qualifiers elaborate on results, usually with respect to uncertainty. Please refer to the 'RESULT QUALIFIERS' section of this file for the meaning of each result qualifier.
Remark Code (1 and 2): 		Some results are accompanied by remark codes. Remark codes provide further detail on the sample, the analysis, or the result. Please refer to the 'REMARK CODES' section of this file for the meaning of each remark code.
Sample ID:			Each sample in the Drinking Water Surveillance Program database is uniquely identified by a 7-digit ID number.
Result ID:			Each result in the Drinking Water Surveillance Program database is uniquely identified by an 8-digit ID number.



TABLE: RESULT QUALIFIERS

<T	A Measurable Trace Amount:interpret With Caution



TABLE: REMARK CODES

ABH: Approximate Result: May Be Biased High
ABM: Approximate Result: Indeterminate Background Matrix
AHS: Approximate Result: Heterogeneous Sample
AIN: Approximate Result: Interference Suspected
AIS: Approximate Result: Insufficient Sample
APL: Additional Peak, Large, Not Priority Pollutant
APS: Additional Peak, Small, Not Priority Pollutant
AQH: Result Biased High, Qc Out of Range
AQL: Result Biased Low, Qc Out of Range
ASOL: Potentially Biased Low Due to Their Low Water Solubility
CRO: Calculated Result Only
ELI: Semi-quantitative Results for Total Microcystins
FAQ: Fraction of Sample Analysed:  Aqueous Phase Only
IM:  Interference Suspected (Sample Matrix)
IS:  Interference Suspected
OCR: Result Outside of Calibrated Range
OMR: Result Outside of Monitored Range
PIL: Preserved in Laboratory
PSS: Particulates Present in Submitted Sample
RDB: Calculated via Digested Blank From Another Run
RDS: Result Obtained on Diluted Sample
RMP: P&m Xylene Not Separated
RRR: Reported Result Obtained by Repeat Analysis
RRV: Reported Result Verified by Repeat Analysis
RVU: Reported Value Unusual:  Unable to Reanalyse
S24: Sample Settled 20-40% During 1 Minute Test Period
S46: Sample Settled 40-60% During 1 Minute Test Period
S6+: Sample Settled Over 60% During 1 Minute Test Period
SCD: Sample Decanted and Combined From Duplicate Vials
SFA: Sample Filtered - Filtrate Analyzed
SIP: Sample Improperly Preserved
SPL: Several Peaks, Large, Not Priority Pollutants
SPS: Several Peaks, Small, Not Priority Pollutants
SRH: Recovery Higher Than Upper Control Limit
X1:  Diluted by 10. Detection Limits Are 10 Times Normal
X10: Diluted by 3. Detection Limits Are 3 Times Normal
X4:  Diluted by 2. Detection Limits Are 2 Times Normal
X7:  Diluted by 5. Detection Limits Are 5 Times Normal
X8:  Diluted by 2.5. Detection Limits Are 2.5 Times Normal
X9:  Diluted by 20. Detection Limits Are 20 Times Normal
X9:  Diluted by 20 Detection Limits 20 Times Normal
