Oilfield Surface Impoundment Closure Guidelines

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The closure guidelines and attachments refered to below are found in the Letter to the Oil and Gas Operator - pdf.

Step 1: Performs preliminary work and testing.

Step 2: Submit BLM form 3160-5 "Sundry Notices and Reports on Wells".  Provide information in Attachment 2. Sign and return a copy of Attachment 7, Statement of responsibility.

Step 3: BLM receives Sundry and considers closure's impact on other resources and activities.

Step 4: BLM sends approved Sundry to Operator with:

1. Letter of approval, and
2 .Conditions of approval

All changes to this approved plan must be communicated to and approved by the BLM.

Step 5: Excavate and process or dispose of sludge as specified in the approved Sundry. The presence of sludge will be determined using ASTM Method D4318 (Attachment 4).

Step 6: Excavation may cease following removal of the sludge if the following is documented to the BLM:

1.There is no known aquifer beneath the sump or the shallowest groundwater beneath the sump is an EPA exempted aquifer,
OR
2. the sump is in a field where a hydrocarbon bearing zone extends to the surface.

If either of these two conditions are applicable, proceed to Step 8. Otherwise, proceed to Step 7.

Step 7:

If the conditions in Step 6 do not apply, excavation must continue until all visibly stained soil is removed
OR
the Operator will provide the information in Attachment 6, Step 3.d. in the "Subsequent Report Abandonment".

Step 8: Collect one composite sample from the bottom of the excavation (same procedure as in Attachment 1, Step 2). Submit the sample for the following analyses:

1. Total Petroleum Hydrocarbons (EPA 418.1).
2. General Minerals (Attachment 5).
3. Benzene, Toluene, Ethylbenezene, Xylene (STEX), (EPA8020).

Step 9: Photograph "post-excavation" conditions at the site. Date and label the photograph.

Step 10: Fax or send to the BLM the results of sample analyses from step 8 and a request for approval to backfill. BLM may grant approval by phone subject to the results of the analyses. A BLM on-site inspection may be needed prior to approval.

Step 11: Backfill the site. Grade and compact to prevent ponding. If no development is planned for the site, place one foot of uncompacted soil as a final cover. Three percent grading after compaction is recommended.

Step 12: Photograph "post-work" conditions at the site. Date and Label the photographs.

Step 13: Submit BLM form 3160-5: "Sundry Notices and Reports on Wells" Provide information in Attachment 6.

Step 14: BLM evaluates the "Subsequent Report of Abandonment" Sundry. If no additional work is needed and site reclamation has been successful, the Subsequent Report will be approved.