skip navigational links United States Department of Labor
A to Z Index | Find It! in DOL |            [skip navigational links]     Search MSHA's Website   Search MSHA
Printer Friendly Version
U.S. Department of Labor          

Mine Safety and Health Administration
1100 Wilson Boulevard
Arlington, Virginia 22209-3939                    

EFFECTIVE DATE:  August 15, 2008 EXPIRATION DATE:  03/31/2010
(Reissue of I06-IV-1)                 


                     Administrator for Metal and Nonmetal
                       Mine Safety and Health

SUBJECT:     Procedures for Documenting Inspections of Impoundments on
                    Regular (E01) Inspections

This Procedure Instruction Letter (PIL) applies to all Metal and Nonmetal enforcement personnel conducting inspections of impoundments at mine and mills during regular (E01) inspections.

This PIL provides guidance for enforcement personnel in documenting inspections conducted of impoundments at metal and nonmetal mines and mills during regular inspections. These inspections should be documented on one of two approved MSHA forms depending on whether it is an initial or subsequent inspection of a structure.

Procedure Instruction
The attached spreadsheet (Attachment 1) should be used by enforcement personnel to determine whether a water or waste material containment structure at a mine or mill is an MSHA recognized impoundment. If it is determined that the structure is an impoundment, it will be appropriately classified and subsequently inspected.

For structures determined to be impoundments, enforcement personnel will initially classify the structure the first time a regular inspection is conducted at a new mine or mill, as soon as practical after an impoundment is constructed, or during its construction. Inspection form 4000-127 (Attachment 2) will be completed by enforcement personnel documenting their observations during this initial inspection. Mine operators and miners representatives, if appropriate, will be informed of the impoundment's hazard classification and why this rating was assigned. Enforcement personnel should also request a copy of the mine operator's "Emergency Action Plan" regarding this impoundment if they have such a plan. These plans are often required by other federal or state agencies.

On subsequent regular inspections, enforcement personnel will complete form 4000-0127a and review impoundment information previously documented on form 4000-127 so they are familiar with each such structure on a mine or mill site. During these inspections, enforcement personnel will verify that the information initially entered on form 4000-127 is correct and that the structure's hazard classification is still appropriate. Incorrect impoundment information or any changes to its hazard classification due to deterioration, increased capacity, location of people downstream, etc…, should be noted on the previously completed 4000-127 form. Enforcement personnel should then complete form 4000-127a (Attachment 3) based on information gained from their inspection. District Dam Safety Representatives should be contacted if any of items 9 through 23 (excluding item 12) on form 4000-127a are checked "yes" so a determination can be made as to whether an inspection is warranted by an impoundment specialist.

Completed form 4000-127a and an updated (if applicable) form 4000-127 should be attached to every regular inspection report for mines or mills having impoundments.

A copy of form 4000-127a (and form 4000-127 if applicable) should be forwarded to the District Dam Safety Representative after the regular inspection is concluded. District Dam Safety Representatives will also be provided with a copy of the mine's "Emergency Action Plan" if one was obtained from the mine.

The District Dam Safety Representatives will enter any new or changed information noted on form 4000-127 into the MSIS database as soon as practical. District Dam Safety Representatives shall also retain completed 4000-127 forms and, if provided, the mine's latest "Emergency Action Plan" relevant to impoundments indefinitely. Form 4000-127a will be maintained for the last three years for each mine or mill in the district having an impoundment.

Field office supervisors shall assure that all impoundments are inspected during every regular inspection. They should also assure that observations made by enforcement personnel during those inspections are noted on the appropriate forms. Further, supervisors should assure that completed impoundment forms are forwarded to the District Dam Safety Representative as soon as possible.

This PIL provides guidance to assure that congressionally mandated inspections of impoundments are performed in accordance with applicable provisions of the Federal Mine Safety and Health Act of 1977 and that these inspections are appropriately documented.

Federal Mine Safety and Health Act of 1977, (as amended) Section 103(a), 30 U.S.C § 801 et seq. at § 813 (a);

Filing Instructions
This instruction letter should be filed behind the tab marked "Procedure Instruction Letters" in the binder for Program Policy Handbooks and Procedure Instruction Letters.

Issuing Office and Contact Persons
Lawrence Trainor, MNM Division of Safety and Health, 202-693-9644
E-mail address:

All Program Policy Manual Holders

Back to Top   Back to Top

Mine Safety and Health Administration (MSHA)
1100 Wilson Boulevard, 21st Floor
Arlington, VA 22209-3939
Phone:    (202) 693-9400
Fax-on-demand: (202) 693-9401
Technical (web) questions: Webmaster
On-line Filing Help:
or call (877) 778-6055

Contact Us