Question 1

Is Asarco Mission Unit water safe to drink?

Accepted Answer

Asarco Mission Unit (PWS ID: AZ0420005) has 120 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. EPA SDWIS lists this system's service population as 544 people using Groundwater sources.

Question 2

How many people does Asarco Mission Unit serve?

Accepted Answer

EPA SDWIS reports that Asarco Mission Unit serves 544 people (this public water system's service population, not the municipal population of Sahuarita or any other city). It is a Public/Private-owned system using Groundwater water sources with 8 service connections. The operator address is listed in Sahuarita, Arizona.

Question 3

What type of violations does Asarco Mission Unit have?

Accepted Answer

Asarco Mission Unit has 120 total violations: 4 health-based violations (MCL exceedances or treatment failures), 114 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.

Question 4

Has PFAS been detected in Asarco Mission Unit water?

Accepted Answer

No PFAS testing data is available for Asarco Mission Unit under the EPA's UCMR5 monitoring program.

Question 5

What water source does Asarco Mission Unit use?

Accepted Answer

Asarco Mission Unit uses Groundwater as its primary water source. It is classified as a Non-Transient Non-Community Water System, serving the same people for at least 6 months per year.

Question 6

Where does this data come from?

Accepted Answer

All data comes from the EPA Safe Drinking Water Information System (SDWIS) and the UCMR5 PFAS monitoring program. SDWIS tracks compliance for all public water systems regulated under the Safe Drinking Water Act.

Question 7

Where does Asarco Mission Unit sit among U.S. public water systems?

Accepted Answer

According to EPA SDWIS population_served among sitemap-advertised systems (serving 500+), Asarco Mission Unit ranks #27,653 of 29,740 by people served, and #387 of 413 in Arizona. Ordinals use population_served DESC among systems serving 500+ (the sitemap cohort). See /methodology#corpus-placement.

Question 8

How does Asarco Mission Unit's violation count compare nationally?

Accepted Answer

Asarco Mission Unit has 120 recorded EPA SDWIS violations, fewer than 23% of the 29,740 public water systems serving 500 or more people nationwide (the same sitemap cohort used for the corpus-placement ranking above). 77% of that cohort has fewer violations than Asarco Mission Unit. A system can have zero recorded violations and still be actively monitored, and a high violation count often reflects a system that reports thoroughly, not necessarily one with worse water.

Contaminant	Category	Count	Latest
Coliform (TCR)	MR	22	2015
Fluoride	MR	6	1989
Chlorine	MR	3	2016
Fluoride	MCL	3	1980
Nitrate	MR	2	1998
Endrin	MR	2	2001
BHC-GAMMA	MR	2	2001
Diquat	MR	2	2001
Endothall	MR	2	2001
Glyphosate	MR	2	2001
OXAMYL	MR	2	2001
Di(2-ethylhexyl) phthalate	MR	2	2001
Picloram	MR	2	2001
Dinoseb	MR	2	2001
Hexachlorocyclopentadiene	MR	2	2001
Carbofuran	MR	2	2001
Atrazine	MR	2	2001
LASSO	MR	2	2001
Heptachlor	MR	2	2001
2,4-D	MR	2	2001
2,4,5-TP	MR	2	2001
HEXACHLOROBENZENE	MR	2	2001
Benzo(a)pyrene	MR	2	2001
1,2-DIBROMO-3-CHLOROPROPANE	MR	2	2001
ETHYLENE DIBROMIDE	MR	2	2001
Chlordane	MR	2	2001
Simazine	MR	2	2001
Heptachlor epoxide	MR	2	2001
Di(2-ethylhexyl) adipate	MR	2	2001
Methoxychlor	MR	2	2001

Asarco Mission Unit

Asarco Mission Unit standing, high SDWIS violation third

System Details

Violation History

Violation Count vs. the National Corpus

Population served record for Asarco Mission Unit

Nationwide peers

Cross-state systems with comparable violation load

Cross-state systems with smaller service footprints