Ted Schade

Air Pollution Control Officer

Great Basin Unified Air Pollution Control District

157 Short Street

Bishop, California 93514

Dear Mr. Schade:

Thank you for your submission ofthe Great Basin Unified Air Pollution Control District’s

(GBUAPCD’s) 2013 Annual Air Quality Monitoring Network Plan in July 2013. We have reviewed thesubmitted document based on the requirements set forth under 40 CFR 58. Based on the information

provided in the plan, EPA approves all portions ofthe network plan except those specifically identifiedbelow.

Please note that we cannot approve portions ofthe annual network plan for which the information in the

plan is insufficient to judge whether the requirement has been met, or for which the information, as

described, does not meet the requirements as specified in 40 CFR 58.10 and the associated appendices.

EPA Region 9 also cannot approve portions ofthe plan for which the EPA Administrator has notdelegated approval authority to the regional offices. Accordingly, the first enclosure (A. Annual

Monitoring Network Plan Items where EPA is Not Taking Action) provides a listing ofspecific items of

your agency’s annual monitoring network plan where EPA is not taking action.

The second enclosure (B. Annual Monitoring Network Plan Checklist) is the checklist EPA used to

review your plan for overall items that are required to be included in the annual network plan along with

our assessment ofwhether the plan submitted by your agency addresses those requirements.

The first enclosure highlights a subset ofthe more extensive list ofitems reviewed in the second

enclosure. All comments conveyed via this letter (and enclosures) should be addressed (through

corrections within the plan, additional information being included, or discussion) in next year’s annual

monitoring network plan. Also, GBUAPCD received comments from the Los Angeles Department of

Water and Power (LADWP) on specific portions the annual network plan during the public comment

period. GBUAPCD’s responses to these comments were included with the network plan submittal. EPA

also received additional comments outside ofthe public comment period. EPA has determined that

GBUAPCD’s responses to the comments are adequate and has provided supplemental responses to

LADWP’s comments in Attachment C.

Printed on Recycled Paper
Air Quality Analysis Office

Enclosures:

A. Annual Monitoring Network Plan Items where EPA is Not Taking Action

B. Annual Monitoring Network Plan Checklist

C. Response to Comments

cc: Christopher Lanane, GBUAPCD

Gayle Sweigert, California Air Resources Board
B. ANNUAL MONITORING NETWORK PLAN CHECKLIST

(Updated 11/26/2013)

Year: 2013

Agency: Great Basin Unified Air Pollution Control District

40 CFR 58.10(a)(1) requires that each Annual Network Plan (ANP) include information regarding the following types o

monitoring stations including FRM, FEM, and ARM monitors that are part of SLAMS, NCore stations, STN stations, S

stations, and/or, in serious, severe and extreme ozone nonattainment areas, PAMS stations, and SPM monitoring station

40 CFR 58.10(a)(1) further directs that, “The plan shall include a statement of purposes for each monitor and evidence t

each monitor meets the requirements of appendices A, C, D, and E ofthis part, where applicable.” On this basis, review 

requirements listed in 58.10 along with those in Appendices A, C, D, and E.

EPA Region 9 will not take action to approve or disapprove any item for which Part 58 grants approval authority to the 

Regional Administrators, but we will do a check to see ifthe required information is included and correct. The items req

Administrator are: PAMS, NCore, and Speciation (STN/CSN).

Please note that this checklist summarizes many ofthe requirements of 40 CFR Part 58, but does not substitute for those 

contents provide a binding determination of compliance with those requirements. The checklist is subject to revision in t

comments on its contents and structure.

Key:

White = Meets the requirement

Yellow= Requirement is not met, or information is insufficient to make a determination. Action requested in next yea

process (items listed in Enclosure A)
ANP requirement Citation Was the info Does the Notes

within 40 submitted? 1If information

. CFR 58 yes, page #s. provided 3meet

. Flag if the req? 4

incorrect 2?

1. Submit plan by July 1st 58.10 (a)(l) Y N Plan was subm

2. Statement of purpose for each monitor 58.10 (a)(1) N Insufficient info

3. 30-day public comment / inspection period 5 58.10 (a)(1), Y, p.1 Y

58. 10 (a)(2)

4. Modifications to SLAMS network — case when we are 58.10 (a)(2) Y, p.15-17 Insufficient info There is insuff

not approving actual system modifications (i.e., we 58.10(e) if the Flat Rock

will do it outside the ANP process 6) Beach PM10 m

down and relo

5. Modifications to SLAMS network — case when we are 58.10 (a)(2) N/A N/A

approving actual system modifications per 58.14(c) 58.10 (b)(5)

58. 10(e)

58.14 (c)

6. Does plan include documentation (e.g., attached N/A N/A

approval letter) for system modifications that have

been approved since last ANP approval?

7. NCore site operational (by 1/1/2011) 58.10 (a)(3) V. App. A, App. B Y

8. Pb site for 0.5-1.0 tpy sources operational (by 58.10 (a)(4) N/A N/A Pb monitoring 

12/27/2011)

9. NO2plan for area-wide and RA4O sites submitted by 58.10 (a)(5) N/A N/A Area-wide NO2 

7/1/2012

10 NO2area-wide and RA4O sites operational by 58.10 (a)(5) N/A N/A Area-wide NO2 

1/1/2013

11 NO2plan for near-road sites submitted by 7/1/2013 58.10 (a)(5) N/A N/A Near-road NO2

12 SO2sites operational (by 1/1/2013) 58.10 (a)(6) N/A N/A 502 monitorin

and 58.13(d)

13 AQS site identification number for each site 58.10 (b)(1) Y, p.20, App. A V

1 Response options: NA (Not Applicable), Yes, No, Incomplete, Incorrect. The responses “Incomplete” and “Incorrect” assume that some inform

2 To the best of our knowledge.

Assuming the information is correct

4Response options: NA (Not Applicable) — [reason], Yes, No, Insufficient to Judge.

The affected state or local agency must document the process for obtaining public comment and include any comments received through the pu

their submitted plan. 6 See 58. 14(c)
ANP requirement Citation Was the info Does the Notes

within 40 submitted?’ If information

CFR 58 yes, page #s. provided 3meet

Flag if the req? 4

incorrect 2?

14 Location of each site: street address and geographic 58.10 (b)(2) V, App. A V

coordinates

15 Sampling and analysis method(s) for each measured 58.10 (b)(3) Y, p.21, App. A V

parameter

16 Any proposals to remove or move a monitoring 58.10 (b)(5) Y, p.15-17 Insufficient info There is insuf

station within a period of 18 months following plan if the Flat Roc

submittal Beach PM10 m

down and rel

17 Scale ofrepresentativeness for each monitor as 58. 10(b)(6); Y, p. 7, App. A V • defined in Appendix D App D

18 Identification ofsites suitable and sites not suitable 58.10 (b)(7) Y, App. A V

for comparison to the annual PM2.5NAAQS as

described in Part 58.30

19 MSA, CBSA, CSA or other area represented by the 58.10 (b)(8) N/A N/A There are cur

monitor GBUAPCD’s ju

20 Designation of any Pb monitors as either source- 58.10 (bX9) N/A N/A Currently the

oriented or non-source-oriented

21 Any source-oriented Pb site for which a waiver has 58.10 (bXlO) N/A N/A Source orient

been granted by EPA RA

22 Any Pb monitor for which a waiver has been 58.10 (b)(11) N/A N/A Currently the

requested or granted by EPA RA for use ofPb-PM 10

in lieu ofPb-TSP

23 Identification ofrequiredNO 2monitors as either near- 58.10 (b)(12) N/A N/A Near-road/Ar

road or area-wide required

24 Identification of any PM2FEMs and/or ARMs not 58.10 (b)(13) N/A N/A The PM2.5FEM 

eligible to be compared to the NAAQS (Note 1: must 58.11 (e) comparable t

include required data assessment.) (Note 2: Required

SLAMS must monitor PM2with NAAOS

comparable monitor at the required sample

frequency.)
ANP requirement Citation Was the info Does the Notes

within 40 submitted? 1If information

CFR 58 yes, page #s. provided 3meet

Flag if the req? 4

incorrect 2?

25 For SPMs listed as non-regulatory, note the start Date 58.20(c) N/A N/A Data from T-4, 

ofFRMJFEMJARM at SPM. If> 24 months, and the Dust ID Pr

monitor is eligible for comparison to the NAAQS per NAAQS compa

58.11 (e) and 58.30, the agency must supply submitted to A

information that App A, C or E requirements were not

met.

26 Document how states and local agencies provide for 58.10 (c) N Insufficient info Information n

the review of changes to a PM2.5monitoring network

that impact the location of a violating PM2.5monitor.

27 Does the plan include a request for approval for and 58.11 (a) (2) N/A N/A The plan does 

alternative to appendix A requirements for SPMs of an alternati

operating a FRM/FEMJARM which also meets

appendix E?

28 Precision/Accuracy reports submitted to AQS 58.16(a); Y, p.18 Y

AppA, 1.3

and 5.1.1

29 Annual data certification submitted 58.15 Y, p.18 V

App. A 1.3

30 Frequency offlow rate verification for manual PM App A 3.3.2 Y, App. A Y

samplers audit

31 Frequency offlow rate verification for automated PM App A 3.2.3 Y, App. A Y

analyzers audit

32 Frequency of one-point flow rate verification for Pb App A N/A N/A Pb monitoring 

samplers audit 3.3.4.1

33 Frequency of one-point QC check (gaseous) App. A 3.2.1 Y, App. A Y

34. Date of last Annual Performance Evaluation (gaseous) App. A 3.2.2 N Insufficient info Information n

35 Dates of last two semi-annual flow rate audits for PM App A, 3.2.4 V. p.22 V

monitors and 3.3.3

36 Dates oflast two semi-annual flow rate audits for Pb App A N/A N/A Pb monitoring 

monitors 3.3.4.1
ANP requirement Citation Was the info Does the Notes

within 40 submitted? 1if information

. CFR 58 yes, page #s. provided 3meet

Flag if the req? 4

incorrect 2?

37 PM2.5collocation App A 3.2.5 Y, p21, App. A Y The plan doe

.

detail, but th

operating in t

appropriately 

38 Designation of a primary monitor ifthere is more than Need to N Insufficient info Information 

one monitor for a pollutant at a site, determine

collocation

39 Distance between collocated monitors (Note: waiver App. A Y, App. A Y

request or the date of previous waiver approval must 3.2.5.6 and

be included ifthe distance deviates from 3.2.6.3

requirement.)

40 Manual PM10 method collocation met? (note: App A 3.3.1 Y, App. A Y The plan doe

continuous PM10 does not have this requirement) detail, but th

operating in 

appropriately 

41 Pb collocation App A N/A N/A Pb monitorin

3.3.4.3

42 PM1025 collocation (note: only applies to Fresno and App A 3.3.6 N/A N/A PM12.5collo

Phoenix NCore sites)

43 Jnstrumentlmonitoring method code for each monitor: App C 2.4.1.2 Y, p. 21, App. A Y

is it reported properly? Is it reported correctly (i.e., . -

appropriate method code for regulatory monitors)?

44 For agencies that share monitoring responsibilities in App D 2(e) N/A N/A GBUAPCD cu

an MSAJCSA: does each affected State or local requirement

agency meet full monitoring requirements or is

an agreement between the affected agencies and the

EPA Regional Administrator in place?

45 Start date for each monitor Required to Y, App. A Y

determine if 
ANP requirement Citation Was the info Does the Notes

within 40 submitted? 1If information

CFR 58 yes, page #s. provided 3meet

Flag if the req? 4

incorrect 2?

other req.

(e.g.,min#

and colloc)

are met

46 Instrument monitor type for each monitor Required to N Insufficient info Information no

determine if

other req.

(e.g.,min#

and colloc)

are met

47 Monitoring objective for each instrument App D 1.1 N Insufficient info Information n

58.10 (b)(6)

48 Site type for each instrument App D 1.1.1 V, p.7, App. A Y

49 Instrument parameter code for each instrument Required to Y, p. 21 Y

determine if

other req.

(e.g., mm #

and colloc)

are met

50 Instrument parameter occurrence code for each Required to Y, P. 21 Y

instrument determine if

other req.

(e.g., mm #

and colloc)

are met

51 Sampling season for ozone (note: date ofwaiver 58.10 (b)(4) Y, App. A Y

approval must be included ifthe sampling season App D, 4.1(i)

deviates from requirement)

52 Sampling schedule for PM25 - applies to year-round 58.10 (b)(4) Y, p. 21 Y

and seasonal sampling schedules (note: date of waiver 58.12(d)

approval must be included ifthe sampling season App D 4.7

deviates from requirement) EPA

flowchart

53 Sampling schedule for PM10 58.10 (b)(4) V. P.21 V

58. 12(e)

App D 4.6
ANP requirement Citation Was the info Does the Notes

within 40 submitted? 1If information

CFR 58 yes, page #s. provided 3meet

. Flag if the req? 4

incorrect 2?

54 Sampling schedule for Pb 58.10 (b)(4) N/A N/A Pb monitorin

58.12(b)

AppD4.5

55 Sampling schedule for PM125 58.10 (b)(4) Y, p.21 Y

58.12(f)

AppD4.8

56 Minimum#ofmonitorsforO 3[Note: should be App D,4.1(a) N/A N/A Minimum nu

supported by MSA ID, MSA population, DV, # and

monitors, and # required monitors] (see footnote) 7 Table D-2

57 Identification of max. conc. 03 monitor(s) App D 4.1 (b) N/A N/A

58 Minimum monitoring requirements met for near-road App D 4.3.2 N/A N/A Minimum nu

NO2(2014 start date) not required

59 Minimum monitoring requirements met for area-wide App D 4.3.3 N/A N/A Minimum nu

NO2 not required

60 Minimum monitoring requirements met for RA-40 App D 4.3.4 N/A N/A Minimum nu

NO2 required

61 Minimum monitoring requirements met for SO2 App D 4.4 N/A N/A Minimum nu

[Note: Only monitors considered to be required required SLAMs are eligible to be counted towards meeting

minimum monitoring requirements.]

62 Minimum monitoring requirements met for Pb [Note: App D 4.5 N/A N/A Minimum nu

Only monitors considered to be required SLAMs are 58.13(a)

eligible to be counted towards meeting minimum

monitoring requirements.]

63 Minimum # ofmonitors for PM2.5[Note 1: should be App D, Y, p. 18, App. A N/A Minimum nu

supported by MSA ID, MSA population, DV, # 4.7.1(a) and required. monitors, and # required monitors] [Note 2: Only Table D-5

monitors considered to be required SLAMs are

eligible to be counted towards meeting minimum

monitoring requirements.]

64 Optional PM2.5Network Clarifications: Provide a list Need to N/A N/A

ofrequired sites ifit does not include all SLAMS. assess several

Only monitors considered to be required SLAMS are eligible to be counted towards meeting minimum monitoring requirements. In addition, o

traffic count/distance requirements to be neighborhood scale (40 CFR 58 Appendix E, Table E-1) caimot be counted towards minimum monitor
ANP requirement Citation Was the info Does the Notes

within 40 submitted?’ If information

CFR 58 yes, page #s. provided 3meet

Flag if the req? 4

incorrect 2?

[Note: default will assume all SLAMS are considered requirements

required sites.]

65 Required PM2,sites represent area-wide air quality App D V. App. A V

4.7.1(b)

66 For PM2.5,is at least one site at neighborhood or App D Y, App. A V

larger scale in an area of expected maximum 4.7. 1(b)(1)

concentration

67 If additional SLAMS PM2.5required, is there a site in App D N/A N/A Additional PM2.

an area ofpoor air quality 4.7.1(b)(2)

68 Minimum monitoring requirements for continuous App D 4.7.2 Y, p.21, App. A Y

PM2.5

69 Requirements for PM2.5background and transport App D 4.7.3 N/A N/A PM2.5backgrou

sites requirements

70 Are PM2.5Chemical Speciation requirements met for App D 4.7.4 N/A N/A PM2.5STN sites 

official STN sites?

71 Minimum # ofmonitors for PM10 App D, 4.6 Y, p.18, App. A N/A Minimum num

(a) and Table required.

D-4

72 Minimum monitoring requirements met for PM12.5 App D 4.8 Y, p.21, App. A V

mass

73 Distance ofsite from nearest road App E 6 Y, App. A Y

74 Traffic count ofnearest road App B V, App. A V

75 Groundcover App E 3(a) V. App. A Y

76 Probe height App E 2 Y, App. A V

77 Distance from supporting structure App E 2 N Insufficient info Information n

78 Distance from obstructions on roof App E 4(b) V. App. A V

79 Distance from obstructions not on roof App E 4(a) Y, App. A V

80 Distance from trees App E 5 Y, App. A Y

81 Distance to furnace or incinerator flue App E 3(b) V, App. A V

82 Unrestricted airflow App E, 4(a) Y, App. A V

and4(b)

83 Probe material (if applicable) App E 9 Y, App. A V

84 Residence time (if applicable) App E 9 V, App. A V
Public Comments on Annual Network Plan

Were comments submitted to the S/LIT agency during the public comment period? Yes

If no, skip the remaining questions.

If yes:

• Were any ofthe comments substantive? No

o If yes, which ones?

o Explain basis for determination if any comments were considered not substantive:

• Did the agency respond to the substantive comments?

o If yes, was the response adequate?

• Do the substantive comments require separate EPA response (i.e., agency response wasn’t adequate)? No

• Are the sections ofthe annual network plan that received substantive comments approvable after consideration o

o If yes, provide rationale:

p

g

, 

, 

fmal 2013 ANP submitted to EPA on August 22, 2013. LADWP subsequently sent letters to

EPA on July 31, 2013, September 3, 2013, and December 3, 2013 that expanded upon the

comments made in the July 9, 2013 letter and provided additional comments on EPA’s annual

network pian approval process. In this document we have summarized and responded toLADWP’s comments, as contained in these letters.’

Comment 1: LADWP suggests that without a compliant network monitoring plan that is

approved by EPA, the data cannot be used for determining the attainment status of any areascovered by the plans or impose air quality mitigation requirements upon LADWP nor any other

party. Specifically, EPA should designate all ofthe data in the Air Quality System (AQS)

database since 2006 with an “N” value, and state that the data cannot be used for attainmentdeterminations or any other purposes.

Response: The primary purpose ofthe ANP is to “provide for the establishment and maintenance

of an air quality surveillance system that consists of a network of [State or local air] monitoring

stations [(SLAMS)].” 2The ANP also provides a mechanism for EPA review and approval of

SLAMS network modifications. 3The quality, and hence validity, ofthe data produced by a

monitoring network described in an agency’s ANP is not necessarily dependent on EPA approval

ofthe ANP. For example, a network with too few monitors would not meet the requirements of

Appendix D to part 58, but the data from each monitor might well still be valid for regulatory

purposes.

Moreover, even when considering the quality of data from a single monitor, 40 CFR 58

Appendix A, § 1(a) provides that “EPA and monitoring agencies shall use a ‘weight of evidence’

approach when determining the suitability of data for regulatory decisions” and “EPA reserves

the authority to use or not use monitoring data submitted by a monitoring organization whenmaking regulatory decisions based on the EPA’s assessment ofthe quality ofthe data.” In using

a “weight of evidence” approach, EPA typically evaluates the quality ofthe data and itsappropriateness for regulatory purposes using a number of different sources ofinformation,

which include Technical System Audits (TSA), data audits, review of ambient and quality

assurance/quality control (QAJQC) data reported to AQS, and the ANP review process.

1 Pursuant to 40 CFR 58.1 0(a)(2), EPA is not required to provide a separate opportunity for public comment when

the State or local agency has already provided such an opportunity, has made no changes subsequent to that

comment opportunity, and has submitted the received comments together with the plan. Nonetheless, in thisinstance, we have exercised discretion to take into consideration LADWP’s July 31, 2013, September 3, 2013, and

December 3, 2013 comment letters to EPA, as well as its July 9, 2013 letter to GBUAPCD.

240 CFR 58.10(a)(1).

40 CFR 58.10(a)(2).
former sites are necessary to achieve the NAAQS or ensure compliance with any other existinglegal or regulatory requirements.

Response: The ANP is an appropriate venue to discuss the discontinuation of monitoring sites

and information pertaining to these should be included in the ANP until appropriate replacementsites can be approved by EPA. 4Whether or not these sites are necessary to achieve the NAAQS

or ensure compliance with any other existing legal or regulatory requirements, all system

modifications to the SLAMS network are subject to approval by EPA, based on criteria set forth

in 40 CFR 58.14(c). Currently, the shutdown and relocation ofthese sites has not been approved

by EPA under the applicable requirements of 40 CFR 58.14 and therefore it is appropriate forthem to be included in the plan at this time.

Comment 3: GBUAPCD continues to operate its PM10 and PM25 network in the Owens Valley

without an EPA-approved Quality Assurance Project Plans (QAPP). While LADWP

acknowledges that GBUAPCD’s SLAMS network is covered under an approved California Air

Resources Board (ARB) Quality Assurance Plan (QAP), they contend that the ARB QAP doesnot cover the use ofthe data used to identif’ supplemental dust control areas on Owens Lakebecause the ARB QAP does not properly assure quality for all ofthe instrument systems that areused in the dust source identification process 5.LADWP also asserts that the QAPPs should beapproved in a public proceeding, the 2013 ANP cannot be approved until there are approved

QAPPs for the SLAMS network, and the data cannot be certified or be used for determining

attainment status ofthe Owens Valley Planning Area (OVPA) or imposing air quality mitigationobligations upon LADWP.

Response: As previously mentioned in Attachment D of EPA’s 2012 ANP approval letter,

LADWP’s initial comments on the 2012 ANP, the subsequent September 28, 2012 letter, andLADWP’s initial July 9, 2013 comment letter on the 2013 ANP all acknowledge that the

GBUACPD’s SLAMS network is covered by ARB’s QAP and specifically state that “to beclear. . .the ARB QAPP [sicj does cover the State and Local Monitoring Stations (SLAMS)

network that is the subject ofthe 2013 ANP.”To further explain, the GBUAPCD SLAMS network is currently a part ofthe ARB Primary

Quality Assurance Organization (PQAO). 6Therefore, as stated by LADWP, the network is

“See, e.g. 40 CFR 58.10(e) (“All proposed additions and discontinuations of SLAMS monitors in annual monitoring

network plans.. . are subject to approval according to §58.14.”)

See July 9, 2013 LADWP comment letter that specifically states that “to be clear.. .the ARB QAPP does cover the

State and Local Air Monitoring Stations (SLAMS) network that is the subject ofthe 2013 Network Plan”.

6 See 40 CFR part 58, appendix A, §3.1.
pp

p

p

p

As previously mentioned, based on the information available, EPA does not agree withLADWP’s assertion that PM10 data collected by GBUAPCD cannot be used for regulatory

purposes.

Comment 4: The current GBUAPCD monitoring network design is problematic because it

focuses on Owens Lake and does not adequately assess contributions from other source areas.

LAWDP also requests that GBUAPCD identify the major off-lake source areas and asserts that

all ofthe source impact monitors around Owens Lake should be designated as special purpose

monitors (SPM5) because they are not suitable for comparison with and determination ofthe

area’s compliance with the NAAQS.

Response: As previously mentioned in Attachment D of EPA’s 2012 ANP approval letter,

comments concerning which sources are influencing specific monitors are beyond the scope of

what EPA is required to review and approve as part ofthe annual network plan process.

Generally, ambient air monitoring network design is performed by the State or local air districts

and there are no specific requirements in 40 CFR Part 58 Appendix D, 4.6 that mandate a PM10

network capture influences from specific sources. Currently, the PM10 network in the OwensLake nonattainment area meets the applicable requirements in 40 CFR 58 Appendix D.Also, the fact that the GBUAPCD SLAMS monitors have site types of “source oriented” 7is not a

sufficient reason to suggest all the SLAMS monitors around Owens Lake should be designatedas SPMs 8or that the data are not suitable for comparison with and determination ofthe area’scompliance with the NAAQS. There is no current language in any portion of 40 CFR 50 or 40CFR 58 that suggests “source oriented” PM10 monitors shoul4 not be used in regulatory

decisions.

Comment 5: The Keeler PM2.5and PM10 monitors, and the North Beach PM10 monitor appear to

violate the EPA siting criteria contained in 40 CFR Part 58 Appendix E, §3(a) due to their closeproximity to a number of unpaved roads and that EPA has incorrectly applied its own monitor

siting regulations.

GBUAPCD refers to “source oriented” site types in the 2013 ANP. EPA interprets this to be the same as “source

impact” site types as described in AQS. 8 See 40 CFR 58.20 (“An SPM is defined as any monitor included in an agency’s monitoring network that theagency has designated as a special purpose monitor in its annual monitoring network plan and in AQS . . .“). Note

that data from an SPM that has operated longer than 24 months is generally comparable to the NAAQS. Id.
these monitors away from such sources may underestimate the population’s exposure to harmful

levels ofPM10and PM2.5Due to the monitoring objectives ofthese sites and their distance from

roadways, the presence of nearby unpaved roads does not violate EPA’s siting criteria in 40 CFR

58 Appendix E.Comment 6: The 2012 ANP does not adequately explain the April 2011 discontinuation ofthe

Flat Rock PM, 0monitor.

Response: As previously mentioned in Attachment D of EPA’s 2012 ANP approval letter,

EPA agrees that there was insufficient information included in the 2012 ANP concerning the

shutdown and relocation ofthe Flat Rock PM10 monitor. System modifications to the SLAMS

network must meet specific criteria outlined in 40 CFR 58.14 and be subsequently approved byEPA. As there was not enough information to judge whether the shutdown and relocation oftheFlat Rock monitor was appropriate, EPA is not taking action at this time on the modification andwill continue to work closely with GBUAPCD to appropriately document the shutdown and

relocation.

Comment 7: The Coso Junction PM10 monitor is in violation ofEPA’s siting criteria and there

are numerous sources improperly influencing the monitoring data. Also, the data from the Coso

Junction is unreliable and cannot be used to assess the emission contributions from Owens Lake.

Response: Currently, there is no evidence in the ANP to suggest that the Coso Junction PM, 0

monitor is in violation ofthe siting criteria of 40 CFR 58 Appendix E. As previously mentioned

in Attachment D ofEPA’s 2012 ANP approval letter, an assessment of whether the data from a

specific monitor is influenced by a particular source is beyond the scope of what EPA is required

to review and approve as part ofthe annual network plan process. Generally, ambient air

monitoring network design is performed by the State or local air districts and there are no

specific requirements in 40 CFR Part 58 Appendix D, §4.6 that mandate a PM, 0network captureinfluences from specific sources. In the 2012 ANP, the Cóso Junction is appropriately

characterized as a population oriented (population exposure) and pollutant transport (regional

transport) regional scale monitoring site.

Comment 8: EPA failed to apply its regulations in approving both the 2011 and 2012 ANPs and

properly notifr the public ofthese approvals in the Federal Register. Specifically, EPA approved

Population-oriented monitoring (or sites) means residential areas, commercial areas, recreational areas, industrial

areas where workers from more than one company are located, and other areas where a substantial number of

people may spend a significant fraction oftheir day.

102012 ANP, Table 2.
p

independent items). Each item in the checklist corresponds to a specific requirement within 40CFR part 58 and is judged based on the information submitted in the ANP. In both the April 18,

2013 2012 ANP approval letter and in today’s 2013 ANP approval letter, EPA clearly notes that

it cannot approve portions ofthe annual network plan for which the information in the plan is

insufficient to judge whether the requirement has been met or for which the information, asdescribed in the ANP, does not meet the requirements. In this rigorous review process, EPA hasapplied its regulations in a clear and transparent fashion and has not approved portions ofthe

plan for which EPA does not have the appropriate information to approve. 1’

Furthermore, the mere fact that EPA has not approved certain items in the 2012 and 2013 ANPsdoes not suggest that PM10 data collected by GBUAPCD should not be used in regulatorydecisions. As previously mentioned, EPA typically evaluates the quality ofthe data and itsappropriateness for regulatory purposes using a number of different sources of information,

which include Technical System Audits (TSA), data audits, review of ambient and QAIQC datareported to AQS, and the ANP review process. This is consistent with EPA monitoring

regulations that state, “EPA and monitoring agencies shall use a “weight of evidence” approachwhen determining the suitability of data for regulatory decisions.” (40 CFR 58, Appendix A, §

(1 )(a)). Therefore, the assumption that if even one requirement has not been met within the ANP,

the data cannot be used in regulatory decisions is incorrect, as EPA does not base decisions onthe quality ofthe data solely on the information contained within an ANP, nor is data quality

judged on one requirement. This is also in part due the fact that most information that is required

to be submitted with the ANP can be independently determined to be appropriate through EPA’s

AQS database and other processes.Finally, we note that EPA is not required to publish its actions on annual network plans in theFederal Register because these actions are informal adjudications rather than rulemakings under

the Administrative Procedure Act, 5 U.S.C. 551 et seq.

“It should be noted that the internal EPA emails cited in LADWP’s December 3, 2013 letter reflect staff

deliberations and do not constitute EPA policy or a definitive interpretation ofthe regulatory requirements.