[Code of Federal Regulations]
[Title 40, Volume 22]
[Revised as of July 1, 2003]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR227.27]

[Page 214-215]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 227--CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN 
DUMPING OF MATERIALS--Table of Contents
 
                         Subpart G--Definitions
 
Sec. 227.27  Limiting permissible concentration (LPC).


    (a) The limiting permissible concentration of the liquid phase of a 
material is:
    (1) That concentration of a constituent which, after allowance for 
initial mixing as provided in Sec. 227.29, does not exceed applicable 
marine water quality criteria; or, when there are no applicable marine 
water quality criteria,
    (2) That concentration of waste or dredged material in the receiving 
water which, after allowance for initial mixing, as specified in 
Sec. 227.29, will not exceed a toxicity threshold defined as 0.01 of a 
concentration shown to be acutely toxic to appropriate sensitive marine 
organisms in a bioassay carried

[[Page 215]]

out in accordance with approved EPA procedures.
    (3) When there is reasonable scientific evidence on a specific waste 
material to justify the use of an application factor other than 0.01 as 
specified in paragraph (a)(2) of this section, such alternative 
application factor shall be used in calculating the LPC.
    (b) The limiting permissible concentration of the suspended 
particulate and solid phases of a material means that concentration 
which will not cause unreasonable acute or chronic toxicity or other 
sublethal adverse effects based on bioassay results using appropriate 
sensitive marine organisms in the case of the suspended particulate 
phase, or appropriate sensitive benthic marine organisms in the case of 
the solid phase; and which will not cause accumulation of toxic 
materials in the human food chain. Suspended particulate phase 
bioaccumulation testing is not required. These bioassays are to be 
conducted in accordance with procedures approved by EPA, or, in the case 
of dredged material, approved by EPA and the Corps of 
Engineers.1
---------------------------------------------------------------------------

    \1\An implementation manual is being developed jointly by EPA and 
the Corps of Engineers, and announcement of the availability of the 
manual will be published in the Federal Register. Until this manual is 
available, interim guidance on the appropriate procedures can be 
obtained from the Marine Protection Branch, WH-548, Environmental 
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460, or 
the Corps of Engineers, as the case may be.
---------------------------------------------------------------------------

    (c) Appropriate sensitive marine organisms means at least one 
species each representative of phytoplankton or zooplankton, crustacean 
or mollusk, and fish species chosen from among the most sensitive 
species documented in the scientific literature or accepted by EPA as 
being reliable test organisms to determine the anticipated impact of the 
wastes on the ecosystem at the disposal site. Bioassays, except on 
phytoplankton or zooplankton, shall be run for a minimum of 96 hours 
under temperature, salinity, and dissolved oxygen conditions 
representing the extremes of environmental stress at the disposal site. 
Bioassays on phytoplankton or zooplankton may be run for shorter periods 
of time as appropriate for the organisms tested at the discretion of 
EPA, or EPA and the Corps of Engineers, as the case may be.
    (d) Appropriate sensitive benthic marine organisms means two or more 
species that together represent filter-feeding, deposit-feeding, and 
burrowing characteristics. These organisms shall be chosen from among 
the species that are most sensitive for each type they represent, and 
that are documented in the scientific literature and accepted by EPA as 
being reliable test organisms to determine the anticipated impact on the 
site; provided, however, that until sufficient species are adequately 
tested and documented, interim guidance on appropriate organisms 
available for use will be provided by the Administrator, Regional 
Administrator, or the District Engineer, as the case may be.

[42 FR 2476, Jan. 11, 1977; 43 FR 1071, Jan. 6, 1978, as amended at 59 
FR 26572, May 20, 1994; 59 FR 52652, Oct. 18, 1994; 61 FR 51203, Sept. 
30, 1996; 65 FR 47325, Aug. 2, 2000]