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Contaminants and Standards
Contaminant Candidate List
Is the Agency going to consider other groups like they have for VOCs under the Drinking Water Strategy Contaminant Groups Effort?
I'd like to know more about the CCL process and when CCL contaminants are determined to need regulation (such as cyanotoxin)?
Why was sodium included on the Contaminant Candidate List 1 (CCL)?
Regarding EPA's regulatory determinations for priority contaminants on the first drinking water contaminant candidate list (CCL), what was the final determination for regulating sulfate?
Primary Drinking Water Contaminants
Aldicarb, aldicarb sulfoxide, and aldicarb sulfone are listed in 40 CFR 141.61(c) with maximum contaminant levels (MCLs) of 0.003 mg/L, 0.004 mg/L, and 0.002 mg/L, respectively. When did EPA promulgate these regulations and when did they become effective?
Are military ships subject to the EPA drinking water regulations for public water systems (PWS) developed pursuant to the Safe Drinking Water Act (SDWA)?
Does the maximum contaminant level goal (MCLG) and maximum contaminant level (MCL) for cyanide apply to free or total cyanide?
Does the Stage 1 Disinfectant and Disinfection Byproducts Rule (Stage 1 DBP) apply to ground water systems?
For initial compliance determination with the Radionuclides Rule, can I composite the samples from all of my wells?
Has EPA promulgated a maximum contaminant level (MCL) and maximum contaminant level goal (MCLG) for nickel?
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Secondary Drinking Water Contaminants
What are the National Secondary Drinking Water Regulations under the Safe Drinking Water Act (SDWA)?
Is the secondary maximum contaminant level (SMCL) for aluminum based on total aluminum?
Is manganese safe in drinking water?
States with primary enforcement responsibility (primacy states) are required to adopt drinking water regulations no less stringent than the national primary drinking water regulations set by EPA (SDWA 1413(a)(1)). Are primacy states also required to adopt
Why does EPA set National Secondary Drinking Water Standards?
Unregulated Contaminant Monitoring Rule
A consecutive system is a public water system (PWS) that receives some or all of its finished water from one or more wholesale systems (40 CFR 141.2). Are consecutive systems subject to the Unregulated Contaminant Monitoring Rule 2 (UCMR 2)?
How will a public water system know if it has perchlorate in its water?
Is it possible to edit the Unregulated Contaminant Monitoring Regulation 2 (UCMR 2) public water system (PWS) inventory data that is pre-populated in the Safe Drinking Water Accession and Review System (SDWARS)?
Our water district has a number of wells that are operated on an as-needed basis. If we wouldn't otherwise run the wells except during a short amount of time, are we required to turn the wells on just to collect the scheduled samples for UCMR3?
The Unregulated Contaminant Monitoring Regulation (UCMR) 1 Monitoring Program was comprised of three separate lists of contaminants. Is there a Pre-Screen Testing List (List 3) of contaminants under UCMR 2?
The sample we took for the Unregulated Contaminant Monitoring Regulation 2 (UCMR 2) did not meet quality control requirements. When should we recollect the sample?
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