Dr. Thomas Mclaughlin

US Nuclear Regulatory Commission

NMSS/DWM/DCB Facilities Decommissioning Branch

Mail Stop T-7F27

Washington, DC 20555

800-368-5642

tgm@nrc.gov

Dr. David Huber

4607M USEPA Headquarters

Ariel Rios Building

1200 Pennsylvania Avenue

N. W. Washington, DC 20460

202-564-4878

huber.david@epa.gov

July 30, 2004

To Drs. Mclaughlin and Huber -

I am writing this letter to request that EPA and NRC amend their current Memorandum

of Understanding or create a new MOU with regard to uranium and other radioactive elements

that have toxicological as well as radiological bioactive properties. I am a technical support

scientist for the Jefferson Proving Ground (JPG; Madison, IN) Restoration Advisory Board

(RAB) and for Save the Valley, an NGO that is active in southeastern Indiana. In the past few

years the Army has begun to address issues related to decommissioning or license termination for

the JPG depleted uranium area. During this time, we (the citizens) have been repeatedly

frustrated by the apparent lack of willingness by EPA representatives or by state agencies to

provide oversight over depleted uranium contamination based on the non-radiological properties

of the metal. The general consensus has been that NRC has regulatory oversight over all

radiological materials,'based on MOUs and (in Indiana) on state regulations. However, NRC

(and specifically Dr. Mclaughlin) has repeated asserted that NRC regulations only address

radiological properties of elements, not the non-radiological, toxicological effects. Thus, I am

writing this letter to encourage your two agencies to produce an MOU to clarify the regulatory

oversight situation. This will help us insist upon more complete guidance and oversight from our

EPA and state agency representatives.

Depleted uranium, as a heavy metal, has both radiological and non-radiological properties

that can cause adverse health effects. In this note, I will focus only on the non-radiological

properties and effects, as they are the reason for the need for a clarifying MOU. As a heavy

metal, depleted uranium will never stop being a heavy metal, and will therefore never stop being

of toxicological concern. It can change oxidation state, and can change form (become soluble or

insoluble, for example); indeed, it can decay to a different element. DU can also migrate into

different environmental media, which can affect how it is taken up by the biota, including
humans. Once in the body the uranium can again change oxidation state, interact and combine

with other elements, and could even [potentially] become organified, all of which will affect

where and how the uranium interacts in the body. As a heavy metal, DU can be stored short term

or long term in many organs, including bone, the nervous systeim, the liver; and DU, like virtually

all heavy metals, will accumulate over time in the kidneys. Until recently, most exposures and

therefore most information about the health effects of the radiological metals was based on high

dose exposure to the more highly radioactive forms. Thus, high dose radiation effects tend to

dominate the older literature. However, the production, testing and use of depleted uranium both

in this country and on the battlefield abroad has led to situations in which civilian exposure can

be expected to be chronic and relatively low dose, both radiologically and toxicologically. As

uranium is a heavy metal, then we can expect the same potential range of effects induced by low

dose, chronic exposure to virtually all non-essential metals. In general, the most sensitive

endpoints for low dose, chronic heavy metal exposure are: nervous system and immune system

dysfunction, reproductive and other endocrine dysfunction and anomalies, and kidney

malfunction and damage, pretty much in that order. By far the most sensitive life stage is preand peri-natal, with the nervous system being the absolutely most critically sensitive organ

system in terms of low dose sensitivity, severity of impact and long term or irreversible damage.

When a civilian population is the target population, it is the developmental heavy metal-related

effects that are of absolutely the greatest concern.

At this time, there is relatively little regulatory guidance for DU with regard to the nonradiological properties. The little guidance that does exist (the relatively recent EPA drinking

water guidance for radionuclides) focuses primarily on the relatively less sensitive kidney

endpoints in mature animals. We believe that once the EPA and NRC have clearly declared that

EPA and the state agencies have oversight over all non-radiological aspects of environmental

depleted uranium, more effort will be made to develop guidance to address what is now

becoming a more common situation: chronic, low dose civilian exposure to DU and other less

radiologically potent radioactive heavy metals. A new or revised MOU between EPA and NRC

will thus help all affected citizens' groups, will help clarify the regulatory oversight situation, and

may help the EPA and state agencies realize that they must develop more extensive guidance for

DU (and other radionuclides) based on their heavy metal-based toxicological potential.

Thank you very much for considering this proposal.

Sincerely,

Diane Henshel

Associate Professor, Indiana University

Sole Proprietor, Henshel EnviroComm

1315 E 10 #340

Bloomington, IN 47405

812 855-4556

dhenshel@indiana.edu