[Code of Federal Regulations]
[Title 40, Volume 8]
[Revised as of July 1, 2007]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR61.344]

[Page 199]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 61_NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS
--Table of Contents
 
   Subpart FF_National Emission Standard for Benzene Waste Operations
 
Sec. 61.344  Standards: Surface impoundments.

    (a) The owner or operator shall meet the following standards for 
each surface impoundment in which waste is placed in accordance with 
Sec. 61.342(c)(1)(ii) of this subpart:
    (1) The owner or operator shall install, operate, and maintain on 
each surface impoundment a cover (e.g., air-supported structure or rigid 
cover) and closed-vent system that routes all organic vapors vented from 
the surface impoundment to a control device.
    (i) The cover shall meet the following requirements:
    (A) The cover and all openings (e.g., access hatches, sampling 
ports, and gauge wells) shall be designed to operate with no detectable 
emissions as indicated by an instrument reading of less than 500 ppmv 
above background, initially and thereafter at least once per year by the 
methods specified in Sec. 61.355(h) of this subpart.
    (B) Each opening shall be maintained in a closed, sealed position 
(e.g., covered by a lid that is gasketed and latched) at all times that 
waste is in the surface impoundment except when it is necessary to use 
the opening for waste sampling or removal, or for equipment inspection, 
maintenance, or repair.
    (C) If the cover and closed-vent system operate such that the 
enclosure of the surface impoundment is maintained at a pressure less 
than atmospheric pressure, then paragraph (a)(1)(i)(B) of this section 
does not apply to any opening that meets all of the following 
conditions:
    (1) The purpose of the opening is to provide dilution air to reduce 
the explosion hazard;
    (2) The opening is designed to operate with no detectable emissions 
as indicated by an instrument reading of less than 500 ppmv above 
background, as determined initially and thereafter at least once per 
year by the methods specified in Sec. 61.355(h) of this subpart; and
    (3) The pressure is monitored continuously to ensure that the 
pressure in the enclosure of the surface impoundment remains below 
atmospheric pressure.
    (D) The cover shall be used at all times that waste is placed in the 
surface impoundment except during removal of treatment residuals in 
accordance with 40 CFR 268.4 or closure of the surface impoundment in 
accordance with 40 CFR 264.228. (Note: the treatment residuals generated 
by these activities may be subject to the requirements of this part.)
    (ii) The closed-vent system and control device shall be designed and 
operated in accordance with Sec. 61.349 of this subpart.
    (b) Each cover seal, access hatch, and all other openings shall be 
checked by visual inspection initially and quarterly thereafter to 
ensure that no cracks or gaps occur and that access hatches and other 
openings are closed and gasketed properly.
    (c) Except as provided in Sec. 61.350 of this subpart, when a 
broken seal or gasket or other problem is identified, or when detectable 
emissions are measured, first efforts at repair shall be made as soon as 
practicable, but not later than 15 calendar days after identification.

[55 FR 8346, Mar. 7, 1990, as amended at 58 FR 3097, Jan. 7, 1993]