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ARMY INSTALLATION ID: MN521382090800

TWIN CITIES ARMY AMMUNITION PLANT

arden hills, Minnesota

Cost So Far

$168M

Money already spent on the evaluation and cleanup of hazardous sites.

Expected Additional Cost

$37.2M

The estimated amount of money needed for evaluation and cleanup of hazardous sites at this installation.

Expected Completion Date

2045

The date by which the DOD estimates cleanup of all sites will be complete. Long term monitoring may continue after this date.

28 Hazardous Sites

Below are the locations of hazardous sites associated with this military installation, according to the DOD. A site’s contamination may affect a much larger area, including public and private lands and the water supplies beneath them.

High Risk

Medium Risk

Low Risk

Risk Not Evaluated or Not Required

Response Complete

We haven't independently confirmed the location of every site. If you notice a site placed at the incorrect location, please contact us.

Not all sites in the DOD data include location information, so there may be sites listed below that are missing from the map. The risk level of a site refers to a relative risk assessment made by the DOD to prioritize the cleanup of sites.

Land Controls & Restrictions

Many sites have been declared “clean” by the DOD but are still not safe for people. This military installation is safe only with the following conditions in place: local use ordinances, signs. see more » signs local use ordinances landfill restriction - prohibit activities that would impact the landfill cap (or cover system) and drainage system prohibit residential use prohibit sensitive use (e.g. hospital, daycare, school) prohibit human consumption of groundwater prohibit installation of drinking water well prohibit groundwater extraction that interferes with remedial action system prohibit or otherwise manage excavation restrict land use - mitigation area(s) protection landfill restriction - restrict plantings that interfere landfill cap or cover system (roots that penetrate the cap or cover system) restrict withdrawal or use of groundwater without treatment « see less

9 Active Sites

Sites where military cleanup actions are still ongoing. The risk level of a site refers to a relative risk assessment made by the DOD, which prioritizes the cleanup of sites that pose greatest threat to safety, human health, and the environment.

Site ID: TCAAP-31

ROUND LAKE

Contaminated Sediments

Cost

$53K

Cost in 2015 plus expected future cost of cleanup

Final Cleanup Action

Aug 2016

This site is under ongoing monitoring until Nov 2016

Contaminated Areas

Sediment (Fresh): Medium Risk

The Tier II Ecological Risk Assessment (USACHPPM, 2004) reported elevated metals concentrations in sediment. The Tier II Ecological Risk Assessment reported effects to benthic organisms based on toxicity testing and chemical concentrations; however, little or no effects for other ecological endpoints.

Contaminants: Cadmium 11.3 mg/kg Chromium 110.0 mg/kg Lead 113.0 mg/kg Zinc 892.0 mg/kg Copper 1250.0 mg/kg

See more details...

Site ID: TCAAP-16

BLDG. 103 (SITE K)

Contaminated Buildings

Cost

Unknown

Final Cleanup Action

Nov 2009

Site ID: TCAAP-17

OU1 DEEP GROUNDWATER

Contaminated Ground Water

Cost

$29K

Cost in 2015 plus expected future cost of cleanup

Final Cleanup Action

May 2000

Site ID: TCAAP-01

BURIAL/BURN AREA (SITE A)

Surface Disposal Area

Cost

Unknown

Final Cleanup Action

Nov 2013

Site ID: TCAAP-19

OU2 DEEP GROUNDWATER

Contaminated Ground Water

Cost

$37.8M

Cost in 2015 plus expected future cost of cleanup

Final Cleanup Action

Jun 2003

Site ID: TCAAP-30

BLDG. 102 DEGREASING OPERATIONS

Contaminated Ground Water

Cost

Unknown

Final Cleanup Action

Dec 2008

Site ID: TCAAP-27

OU3 DEEP GROUNDWATER

Contaminated Ground Water

Cost

$29K

Cost in 2015 plus expected future cost of cleanup

Final Cleanup Action

Aug 2006

Site ID: TCAAP-15

BLDG. 502 AND AREA (SITE I)

Contaminated Buildings

Cost

Unknown

Final Cleanup Action

Sep 2008

Site ID: TCAAP-05

OPEN BURN/DISPOSAL AREA (SITE C)

Burn Area

Cost

Unknown

Final Cleanup Action

Sep 2008

19 Inactive Sites

Sites where military cleanup actions are complete, according to the DOD. Note that this status does not necessarily mean the site is no longer hazardous, as many of these sites are put under long-term monitoring or other restrictions.

Site ID: TCAAP-12

BURN/DISPOSAL AREA (SITE 129-5)

Burn Area

Cost

Unknown

Final Cleanup Action

Sep 2008

This site is under ongoing monitoring until Sep 2045

Site ID: TCAAP-13

DUMP (SITE 129-15)

Landfill

Cost

Unknown

Final Cleanup Action

Sep 2008

This site is under ongoing monitoring until Sep 2045

Site ID: TCAAP-21

OUTDOOR FIRING RANGE

Firing Range

Cost

Unknown

Final Cleanup Action

Sep 2008

This site is under ongoing monitoring until Sep 2045

Site ID: TCAAP-22

WATER TOWER AREA

Surface Disposal Area

Cost

Unknown

Final Cleanup Action

Aug 1996

Site ID: TCAAP-23

BLDG. 135 PRIMER/TRACER AREA

Contaminated Buildings

Cost

Unknown

Final Cleanup Action

Mar 2014

This site is under ongoing monitoring until Sep 2045

Site ID: TCAAP-24

RECREATIONAL TRAP-SHOOTING RANGE

Small Arms Range

Cost

Unknown

Final Cleanup Action

Sep 2000

Site ID: TCAAP-25

OU2 WATERBODIES

Contaminated Sediments

Cost

Unknown

Final Cleanup Action

Jun 2012

Site ID: TCAAP-26

ALL UNCHARACTERIZED AREAS

Surface Disposal Area

Cost

Unknown

Final Cleanup Action

Apr 1996

Site ID: TCAAP-29

AEC PHYTOREMEDIATION DEMO AREAS

Contaminated Ground Water

Cost

Unknown

Final Cleanup Action

Jul 2001

Site ID: TCAAP-28

BLDG. 535 PRIMER/TRACER AREA

Contaminated Buildings

Cost

Unknown

Final Cleanup Action

Jan 2010

Site ID: TCAAP-20

GRENADE RANGE

Firing Range

Cost

Unknown

Final Cleanup Action

Sep 2008

This site is under ongoing monitoring until Sep 2045

Site ID: TCAAP-10

BURN/BURIAL AREA (SITE H)

Burn Area

Cost

Unknown

Final Cleanup Action

Sep 2008

This site is under ongoing monitoring until Sep 2045

Site ID: CCTCAAP-32

ENVIRONMENTAL BASELINE SURVEY AOCS

Contaminated Fill

Cost

Unknown

Final Cleanup Action

Mar 2014

This site is under ongoing monitoring until Sep 2045

Site ID: TCAAP-02

SEWAGE SLUDGE DISPOSAL (SITE B)

Surface Disposal Area

Cost

Unknown

Final Cleanup Action

Apr 2001

Site ID: TCAAP-06

LEACH/BURN PITS (SITE D)

Chemical Disposal

Cost

Unknown

Final Cleanup Action

Sep 2008

This site is under ongoing monitoring until Sep 2045

Site ID: TCAAP-07

DUMP AND BURNING AREA (SITE E)

Landfill

Cost

Unknown

Final Cleanup Action

Sep 2008

This site is under ongoing monitoring until Sep 2045

Site ID: TCAAP-08

OPEN BURN/BURIAL AREA (SITE F)

Burn Area

Cost

Unknown

Final Cleanup Action

Sep 2000

Site ID: TCAAP-09

DUMP (SITE G)

Landfill

Cost

Unknown

Final Cleanup Action

Sep 2008

This site is under ongoing monitoring until Sep 2045

Site ID: TCAAP-11

LEACHING PITS (SITE 129-3)

Disposal Pit and Dry Well

Cost

Unknown

Final Cleanup Action

Sep 2008

This site is under ongoing monitoring until Sep 2045

Update (Dec. 5, 2017): We have changed the source of the installation cost data after being notified by the Department of Defense that they erroneously reported their own cost figures on the DERP website. We are now displaying the costs the department says are the most accurate available, from the Pentagon’s DERP database that we received in a FOIA request.

Note: The risk level of a site refers to a relative risk assessment made by the DOD to prioritize the cleanup of sites.

Data: All data comes from the Defense Environmental Restoration Program and the U.S. Army Corps of Engineers, and will be released soon at the ProPublica Data Store. Read our methodology »