----- Forwarded by Christine Vineyard/R9/USEPA/US on 10/12/2010 10:10 AM -----

From: "Reyes Romero" <reyesromero@co.imperial.ca.us>

To: Christine Vineyard/R9/USEPA/US@EPA

Cc: "Brad Poiriez" <bradpoiriez@co.imperial.ca.us>

Date: 10/05/2010 02:41 PM

Subject: RE: FW: Rule 420 - Response to Comments

Christine:

Attached is a copy of ICAPCD response to Rule 420 comments. We appreciate the opportunity to 

provide additional information to EPA and assist to clarify public comments on this rule.

Thanks,

Reyes Romero 

Assitant Air Pollution Control Officer

150 s 9th Street

El Centro, CA 92243

P (760) 482 4606

F (760) 353 9904

reyesromero@imperialcounty.net

 
Rule 420 Response to Comment Information

On June 18, 2010, the United States Environmental Protection Agency (USEPA) received a 

comment letter regarding the proposed approval of Imperial County Air Pollution Control 

District’s (ICAPCD’s) Rule 420 revision to the State Implementation Plan (SIP) for beef feedlot 

controls. In this document, ENVIRON has provided information that may assist in the 

preparation of responses to the comments outlined in the comment letter (i.e., bullet points in 

the “Concerns and Comments on the Proposed Beef Feedlot Rule” section starting on page 3), 

in the order in which the comment appears. 

I. COMMENT: LACK OF DOCUMENTATION REGARDING SIGNIFICANT SOURCES

“The Proposed Rule analysis shows that, in 2006 for example, uncontrolled beef feedlot 

emissions are above the significance threshold of 5.64 tons per day. Yet, the District claims 

that beef feedlots are a de minimis (not significant) source based on a purported 50% 

emissions reduction that is assumed as credited in 2002. Thus, emissions are calculated at 

a de minimis level of 3.26 tons per day. Yet, this 50% reduction assumption is not 

adequately explained, analyzed or modeled in USEPA’s Proposed Rule. Is this accurate? 

Has it been verified? Where is the background data?”

Response

Cattle feedlot PM10 emissions (controlled and uncontrolled) were the subject of the tri-agency 

(ICAPCD, ARB, EPA) process in the development of the 2005 BACM analysis, including 

resolution and concurrence on the emission inventory. Emissions for that source (controlled 

and uncontrolled), which included the establishment of a 50% control factor for Rule 420, were 

confirmed among the agencies at an August 2, 2005 3-agency call. ARB went through its 

formal traditional inventory review (baseline and controlled) for this source; we note that it 

appears in the official Imperial County inventory based on review of the ARB’s web site 

emission inventory:

• ARB’s website inventory has 2008 cattle feedlot emissions of 3.25 tpd, which is 

consistent with CARB having officially incorporated the Rule 420 emission factor 

(http://www.arb.ca.gov/app/emsinv/emseic_query.php?F_YR=2008&F_DIV=-

4&F_SEASON=A&SP=2009&SPN=2009_Almanac&F_AREA=DIS&F_DIS=IMP&F_EIC

SUM=620).

• For 2000, the emissions are 6.50 tpd, which would reflect “uncontrolled” (pre-rule) 

emissions (http://www.arb.ca.gov/app/emsinv/emseic_query.php?F_YR=2000&F_DIV=-

4&F_SEASON=A&SP=2009&SPN=2009_Almanac&F_AREA=DIS&F_DIS=IMP&F_EIC

SUM=620).

The control method of water application is widely used for fugitive dust mitigation and control 

efficiency has been documented in several EPA reports. The 50% is indeed a “reasonable” 

control factor estimate (and may be low). Watering controls for dust sources generally ranges 

from 50% to 90%.1,2 A 2006 report by E.H. Pechan & Associates, Inc. indicates that watering 

feedlots results in 50% control.

3

 1 USEPA, Fugitive Dust Document and Technical Information Document for Best Available Control 

Measures, EPA-450/2-92-004, September 1992; Sections 3.3.3 and 3.4.2.

In addition, we note that the requirement for 20% to 40% 

2 Western Regional Air Partnership (WRAP), WRAP Fugitive Dust Handbook, September 2006, Table 9-

4.

3 E.H. Pechan & Associates, Inc., Documentation Report, Version 4.1, Pechan Report No. 

06.05.003/9011.002, May 2006; Section III, p. 645.
Page 2

moisture content is greater than other types of moisture content requirements in other fugitive 

dust rules.

II. COMMENT: LACK OF EXPLANATION REGARDING THE 5 MU G/M3 DE MINIMIS 

STANDARD SET FORTH IN 59 FED. REG. 41998 (AUG. 16, 1994)

“How does the tons per day analysis provided by the District as identified above relate to 

this 5 mu g/m3 [sic] standard?”

Response

The explanation was explicitly included and discussed in the 2005 BACM report (Chapter 2 

“Determination of PM10 De Minimus Levels). As discussed on pages 7 and 8 of the 2005 

BACM report, the de minimus (DM) level of emissions related to the 24-hour 5 μg/m3 was 10.1 

tons/day of PM10. That section also notes that ICAPCD chose to use the more restrictive 

annual average DM emission level of 4.9 tons/day in its determination of significant sources. 

(Of course, the annual average PM10 standard is now revoked.) Post-2004 cattle feedlot PM10 

dust emissions are below either calculated DM level, more so for the 24-hour DM level related 

to the 5 μg/m3 significance threshold. 

III. COMMENT: INTERRELATION WITH THE DISTRICT’S RULE 217

“The District’s Rule 420 relies on the permitting scheme for its Rule 217 Confined Animal 

Facility Rule. This Rule has not been approved by USEPA and an analogous rule from the 

San Joaquin Air District (Rule 4570) was analyzed by a January 14, 2010 USEPA Rule in 75 

Fed. Reg. 2079. How do Rule 217, Rule 420, and the USEPA’s decision on San Joaquin’s 

Rule 4570 interrelate?”

Response

We understand that EPA is responding to this comment.

IV. COMMENT: SPECIFIC RULE IMPROVEMENTS

“There should be an established maximum inches of manure stockpile in feedlot pens. For 

example, a three inch maximum. Also, there should be a standardized method of dust 

control for beef feedlots. Methods of dust control should be standardized with an 

enforceable menu or list of applicable options.”

Response

District is unaware of any “maximum inches of manure stockpile” in feedlot pens used in other 

regulations or any analysis indicating related PM10 dust control efficiency. (Also, we are 

assuming that the commenter means manure thickness in the corral, not manure stockpile, 

which is manure pushed into stockpiles for storage before removal or use.) Indeed, SCAQMD 

Rule 1127 included control options consistent with maintaining a minimum corral level of 

manure at least 3” to avoid dust emissions from the underlying soil.

In regards to the rule needing a standardized method of dust control for beef feedlots, although 

the rule does not list specific options for controlling dust from the feedlots, the rule sets 

performance standards (“assuring Manure at all times is maintained at a moisture factor 

between 20% and 40%, in the top three inches in occupied pens”) in section B.1 that must be 

met in order to comply with the rule. Section E of the rule also specifies explicit procedures that 

are to be used in determining the moisture content of the manure, and are thus an enforceable 

method of evaluating compliance with section B.1. 
Page 3

Although such an approach could be used, there are no regulatory requirements that we are 

aware of that a standardized method of dust control is required, either with our without a menu 

or list of applicable dust control options. The rule requires that the moisture level be maintained 

between 20% and 40%, regardless of the amount of water required to maintain that level. On 

different days and on different lots, that may require more or less water which a “standardized” 

method may not capture. In conclusion, there is neither a regulatory requirement nor dust 

control need for a “standardized” method.

V. COMMENT: ENFORCEMENT

“As referenced in the video identified on page one above, we question whether adequate 

enforcement “on the ground” is taking place. There are many instances that dust emissions 

exceed the opacity rule. Are there other enforcement mechanisms that USEPA can 

consider as BACM such as random inspections, increased funding or USEPA verification of 

the District’s enforcement program?”

Response (E-mail from Reyes Romero to Christine Vineyard sent 9/28/2010)

Please be aware that the source identified in the video cited is no longer in operation at the 

location. According to the District’s investigation, after the feedlot site sustained heavy rains in 

the winter of 2009, a failure in the water runoff collection system occurred, which led to various 

pens being severely flooded. As a result, cattle were immediately evacuated from the site and 

the feedlot has been inactive since the incident. Due to the nature of the site’s potential 

violations, this case was investigated by the appropriate agencies, the Imperial County 

Environmental Health Department and the Regional Water Control Board, as a potential health 

issue and not as an air quality matter. The District Permits which are issued to all cattle feedlot 

facilities contain conditions to ensure that the mitigation measures required are fully enforced.

All permitted sources are routinely inspected by the District’s Enforcement Division to determine 

compliance with permit conditions and ICAPCD Rules and Regulations. The District is 

responsible for air quality management activities and inspections within Imperial County. The 

District employs twenty-two full-time employees, five of which make up the Enforcement 

Division. With the current staff, the District is capable of fulfilling all permitting and compliance 

duties. The District conducts unannounced inspections to all permitted sources, including cattle 

feedlots, at a minimum annually, as required by the California Air Resources Board and the 

USEPA. The annual inspections shall be at least a Level II inspection as defined in the 

Environmental Protection Agency’s Inspection Frequency Guidance (March 31, 1988). The 

District is currently implementing a Compliance Monitoring Strategy (CMS) Plan, October 1, 

2005 – September 30, 2011, which has been approved by the USEPA. This plan delineates 

the compliance activities that the District undertakes to implement the EPA’s revised Clean Air 

Act Stationary Source Compliance Monitoring Strategy policy. This plan also requires the 

District to report to EPA the inspections conducted to maintain compliance with the CMS. In 

addition, the District carries out unannounced inspections in response to citizens complaints.

District records demonstrate that inspectors respond and investigate all complaints within 24 

hours of being reported.