UNITEDSTATESENVIRONMENTALPROTECTIONAGENCY
REGIONIX 215FremontStreet SanFrancisco,Ca.94105

February 16, 1989
MEMORANDUM
SUBJECT:Rule Effectiveness
FROM: David L. Calkins, chief IX

## (7)

# ~~ Air Programs Branch, Region
TO: G. T. Helms, Chief 03/CO Branch, AQMD (MD-15)
We have reviewed the proposed alternative program of rule effectiveness evaluation that was prepared by your staff and sent tous bymemo on January 11, 1989. We have the following comments.
Rule Effectiveness

- Comments on the Concept in General
The California Air Resources Board and Air Pollution Control Districts in California place a considerable amount of resources and attention on the preparation of a reliable emission inventory for all air contaminants, criteria and noncriteria. The statewide stationary source emission inventory (forVOC sources greater that 25 tpy and other criteria pollutants) is updated every four years. Inmost Districts, the inventory is updated
more frequently and there is a great deal of confidence that the minor « 25 tpy) sources are also reasonably depicted. For most categories, a compliance factor is built into the emission calculation. Therefore, the State of California believes that their emission inventory is a reasonably accurate representation of the anthropogenic emissions being released in the state.
When the districts put together the inventory, there is an opportunity for the staff engineers to evaluate the reasonableness of the controls in place in a certain emission category. For example, when Stage II Vapor Recovery rules were adopted, the early year inventories reflected poor compliance. The percent compliance has improved over the years, but the inventory still does not reflect 100% compliance. In otherwords, some good engineeringjUdgment and practical enforcement experience is used inthe preparation of the inventory which takes into account rule effectiveness. As the inventory is updated in subsequent years, these factors are further refined to best represent real emission conditions in the airbasin.

# /
Applying the arbitrary 80% rule effectiveness factor to an abatement devicepresentlyusing abatement efficiency of 95%, 80%, or 70% will result in raising emissions from the source by 380%, 80%, and 46.6%, respectively. These values were obtained bycomparing the results of the equationwith a rule**effecti~e** ness factor andwithout. The equation is included.in the guidance documents.
Controlled uncontrolled [1

- (control equip eff) X (rule eff)]

emissions emissions
For a source with 95% control equipment efficiency, without a rule effectiveness factor, themultiplierwould be .05. For the same sourcewith an 80% rule effectiveness factor, the multiplier wouldbe 0.24. This will result in a 380% change in controlled emissions from sourceswhichhave control equipment with 95% efficiency as compared to the inventory figures which the Districts believe is the best estimation of actual emissions.
California places considerable emphasis on maintaining the inventory because they are genuinely concerned that the planning efforts which are based on these numbers will achieve the results they need to attain the NAAQS. In addition, most of the technical work performed in California is continually challenged by representatives of industry and environmental groups.
In California, the state and some of the districts, perform fairly rigorous audits of identified sources in the inventory on a routine basis. When discrepancies are found, an adjustment is made to the emission figures in the inventory. Some of the largerdistrictshave developed their own emissions inventory audit programs which combine permitting, compliance and enforcement program information. All of the districts in California have recently been given authority (under the Sher Bill) to charge emission fees. This programwill reduce overreporting of emissions, while the audit program and compliance inspection will reduce underreporting. It has been suggested that the development of an emission inventory audit programwouldbe a better utilization of emission inventory personnel than filling out 10 source file questionnaires for each source category.
Whilewe all agree that rule effectiveness considerations need to bemade in emission inventory programs, we disagree on where th

## 7**fa~tor** is to be.applied tobest improve the inventory. The appllcatl0n of an arbltrary rule effectiveness factor,**w~ether** derived from questionnaires or a straight 80%, will hlnder rather than improve emission inventory development in the state of California. Therefore, while Californiahas committed to improve their inventory by seasonally adjusting and listing
sources between 10 

### &25 tpy, they will probably not apply a ruleeffectiveness factor tothe final calculationof emissions from each sourcewhen the inventory is submitted to EPA for the Post

_**~98J** Ozone/CO Plans.
We understandthat not all airpollution control programs throughoutthe countryhavethe resources available toplace this much emphasis on inventory'programs, and that the use of the questionnairesmay be a viable optionoforthem. But for agencies whichdo have this luxury, we request that leeway be given to address the issuewith an alternativeprogram. Rule Effectiveness

- Comments onUse of the Point 

### &Area Questionnaires '
The following are comments on the draft questionnaires as providedbyyour office in a memo datedJanuary 11, 1989.
Itmakes some sense todevelop three (or more) point sources questionnaires so thatweighting of factors canbe more equitable and specificto types of operation. We suggest at least the followingthree: solvent use operations, petroleum operations, and fuel combustion operations.
The use of the questionnaires, as opposed to the across the board 80%, is a very resource intensive option for a state or local agency to choose whichmay not result in very much bottom line difference of the baseline emission inventory. Therefore, there is very little incentive to use the questionnaires unless all theirrules are written and enforcedperfectly tomake up the 20%. For area sources, most of the data is based on estimated activity data and number of sources. Correcting this with an arbitrary 80% non-compliance rate will not improve the estimates.
What prevents some states and local agencies from raising all their numbers up by 20% only to apply the factor? Any emission inventorydoes NOT reflect accurate emissions; at its best it is a reasonable representation of emissions of an air basin.
The questionnaires do not allow a rule to be more than 100% effective. What about the situationwhere you have a Continuous EmissionMonitor (CEM) inplace at source and the data shows that the emissions have alwaysbeen under the inventory level? or where a source ispermitted at a specific level basedupon previous economic operating conditions and now the source has reduced operation?

Use of the point sources questionnairemake it very difficult to get 100%, even ifthe real emissions accurately reported in the inventory. For example, if a source does not keep good records, but is in compliancebecause of complianti, coatings (not irreversible) theywouldhave somepoints deducted. It ispossible for a sourcetobe inviolationwith a rule and yet emit emissions lower than the uncontrolledemissions level. Therefore, the application of a rules effectiveness factor would make the inventory an inaccurate reflection ofemissions .from that source.
If you have any questions, pleasecontact Kathi Moore at FTS 454-0567.