390 likes | 526 Views
Why is an air quality improvement plan needed?. Because of constant complaints about conditions inside the tunnel and evidence of actual harm to motorists. Because of the regular tunnel closures due to degraded air quality and rising CO levels.
E N D
Why is an air quality improvement plan needed? • Because of constant complaints about conditions inside the tunnel and evidence of actual harm to motorists. • Because of the regular tunnel closures due to degraded air quality and rising CO levels. • Because of regular reports of ill effects outside the tunnel due to stack and portal emissions. • Because portal emissions have been occurring on a regular basis, as described in the Holmes report on the impact of portal emissions. In other words the situation is already bad and is likely to get worse, unless something is done
The RTA $50 million plan has 4 main parts: • Video cameras to track and fine smoky trucks to reduce emissions. • Extra jet fans for better air flow control. • Portal emissions ( blowing unfiltered air out of the tunnel ends at ground level) to allow for extra fresh air into the tunnel. • A ‘trial’ of filtration equipment at the west end of the west-bound tunnel to reduce ‘haze’.
The RTA submission to Planning goes far beyond the air quality improvement plan: • It proposes to disband the AQCLG and replace it with an ill defined‘Community engagement strategy’, without the defined powers and responsibilities of the current AQCLG. • It calls for a number of changes to the conditions of approval, far beyond those needed to account for the technical changes proposed. • It proposes to remove many of the protections provided in the existing CoA and to significantly reduce RTA accountability to the public.
Although RAPS is supportive of some aspects of the RTA proposal it has made a submission to Planning critical of: • The proposal for portal emissions • The use of portal emissions as a tool to improve in-tunnel air quality • The assumptions about air quality and the continued inappropriate use of the NEPM goals as a performance goal for tunnel emissions • The quality, methodology and inadequate nature of the health risk assessments • The inappropriate and wasteful technical proposal for filtration in the westbound tunnel In addition, RAPS made a specific suggestion about a possible filtration solution to solve the identified problems in the tunnel which removed the need for unfiltered portal emissions
Will it improve the air in the tunnel? Filter • Probably yes. The pollution level inside the tunnel will be roughly halved. • The stack emissions should be reduced by 40%
The RTA plan may ‘work’ for those inside the tunnel, but not for those outside the tunnel: • Portal emissions will significantly increase the impact of harmful diesel fumes on people living round the tunnel portals. • Around $45 million is spent on fixing 1/3 of 1/4 of the “haze” problem in the tunnel. • The remainder of the problem is ‘fixed’ by dumping the diesel emissions out of the portals at ground level. • There is no guarantee that the filters will be kept working after the one year ‘trial’.
The RTA proposal is aimed solely at improving in-tunnel conditions for motorists. The stated aim is to remove the ‘perception’ of a problem with ‘haze’ and to reduce tunnel closures due to bad air quality. But ‘Haze’ is not harmless!!! But ‘Haze’ is not harmless!!! It is made up largely of diesel particle emissions which cause asthma and lung irritation and are now known to trigger heart attacks and cause cancer . According to the California Office of Environmental Health Hazard Assessment its cancer risk factor is 3 in 10,000 for every 1µg/m3 increase in exposure.
The RTA EIS document predicts that the portal emissions will represent an increase in PM10 at the worst location of 0.6µg/m3 per year. This is claimed to represent an increased mortality risk of 1 in 20 million. The RTA compares this with the lifetime risk of being killed by lightning, which is 1 in 1.6 million
This claim is insulting, misleading and, above all, incorrect! It is contrary to the advice given by NSW Health and the EPA about the potential dangers of portal emissions. The risk of 1:20 million claimed by the RTA is a ‘daily’ risk not a ‘lifetime’ risk as is required by the EPA. The corrections placed on the RTA web site are still inadequate and misleading. They still compare daily with lifetime risks
Diesel exhaust is a specific and separate hazard: “Significant health risks are associated with carcinogenic toxic air contaminant emissions in vehicle exhaust. The most significant carcinogenic toxic air contaminants in vehicle emissions are 1,3-butadiene and benzene from gasoline fueled vehicles, and diesel PM from diesel-fueled vehicles.” Appendix to the Draft Recommended Protocol for Evaluating the Location of Sensitive Land Uses Adjacent to Major Roadways. Sacramento Metropolitan Air Quality Management District BUT The list of toxic air components used currently by the NSW EPA, although it includes the same risk factors for Benzene and 1.3 Butadiene as does the OEHHA, DOES NOT INCLUDE DIESEL EXHAUST AS A TOXIC AIR COMPONENT.
California Hot Spots regulation: • California, with its well known pollution problems and its concentration of active research institutions is acknowledged a leader in air pollution science. • California recently introduced the “Hot Spots” Act which is designed to provide information to state and local agencies and to the general public on the extent of airborne emissions from stationary sources and the potential public health impacts of those emissions. • A diesel 'hot spot' is a facility which uses more than 3000 US gallons (about 11000 litres) of diesel fuel per YEAR. All types of 'facilities’ including highways are included. This would clearly cover the M5 tunnel and its emissions. • Agencies in Australia , such as the NSW EPA, routinely follow the lead given in regulation and hazard assessment by the California OEHHA (Office of Environmental Health Hazard Assessment)
In 2003 the OEHHA listed diesel exhaust as a Toxic Air Contaminant with a specific ‘unit risk factor’ This is of real significance to the M5 as the NSW EPA Approved methods document notes "Dose response assessment and risk characterisation can be undertaken in accordance with the following: The Air Toxics Hot Spots Program Guidance Manual for Preparation of Health Risk Assessments (OEHHA 2003) Hot Spots Analysis and Reporting Program (HARP) (CARB 2003a) Hot Spots Analysis and Reporting Program – User Guide Version 1.0 (CARB 2003b).
NSW EPA requires that carcinogenic risks be assessed on the basis of 70 year exposure. • It is clear that diesel exhaust is carcinogenic • Its carcinogenicity is separate from and greater than the risks for benzene and 1.3 butadiene, with which it may be associated • There is no credible argument against the fact of diesel exhaust carcinogenicity, the only argument being about the size of the risk • The best available information is that given by the California OEHHA • Precautionary principles would DEMAND that this information be used as the basis of the assessment of risk from the additional emissions of diesel exhaust from the portals
The cancer risk of the increased emissions is ignored in the RTA submission --- because the NSW EPA has not included diesel exhaust in its list of carcinogenic agents! If only half of the of 0.6 µg/m3 increase in particle levels is due to diesel exhaust, the increase in life-time cancer risk is 90 in a million, according to the California OEHHA guidelines. This is 1,800 times greater than the risk claimed in the RTA. It is 90 times the risk threshold specified by the NSW EPA! If only half of the of 0.6 µg/m3 increase in particle levels is due to diesel exhaust, the increase in life-time cancer risk is 90 in a million, according to the California OEHHA guidelines. The true risk of the tunnel has not been established
RTA proposals for the M5 AQCLG • There are about 800 houses, and at least 4 blocks of units within 500m of the Bexley North portal! • All will receive some increase in pollution from the portal emissions. • The impact at Marsh St is similar.
These people were supposed to be represented by the M5 AQCLG • For all of its imperfections, this group has tried to represent all who are affected by the tunnel and its operation • In the course of the 8 years experience this group has built up a significant body of knowledge and expertise • In a move which seems completely unrelated to an ‘air quality improvement plan’ the RTA proposes to disband the AQCLG in favour of a vague ‘Community engagement strategy’, without the defined powers and responsibilities of the current AQCLG.
The committee’s role under the 1997 conditions ‘includes: input into defining/formulating air quality monitoring requirements; accessing and disseminating monitoring results and other information on air quality issues; and associated potential impacts’ • As a result of the AQCLG’s defined role, the RTA was compelled to make available to the members information relating to the monitoring stations, the operation of the stack and other details of tunnel operation. • No provision is made in the new proposals for this information flow, which enabled community members to identify serious inaccuracies in the stack monitoring and the occurrence of illicit portal emissions
The RTA claims: • The AQCLG does not represent or meet the needs of the broader community, in relation to the operationalaspects relating to the M5 East tunnel • The AQCLG is considered an inadequate forum to discuss broader policy issues. • Issues are not resolved at AQCLG meetings, with a repetitious discussion on issues of concern for particular AOCLG members. • The AQCLG is not linked to the broader community or broader communications process. None of these claims stand up to serious examination, nor does the proposed ‘community engagement strategy’ replace the role of the M5 AQCLG This is not to say that the AQCLG does not require reform , however the role of the AQCLG must be maintained and strengthened
Inappropriate use of NEPM goals for regulatory purposes Both the RTA and the Department of Planning seem determined to continue to use the NEPM goal for particles for the regulation of tunnel emissions. This is in spite of the fact that NEPM goals are not suitable for such a use. The NEPM documentation is quite specific: '‘Conversely, the air quality of some localised areas within major airsheds are dominated by local activities such as that experienced in a road tunnel or a heavily trafficked canyon street. Air quality management in these areas is complex and needs a different approach to that directed at meeting ambient standards intended to reflect the general air quality in the airshed’ (p 13 from NEPM 1998)
Some time ago, RAPS approached the Executive Director of the National Environment Protection Council, Dr. Bruce Kennedy, for an assessment. The reply he gave us leaves no room for disagreement: ‘The NEPM PM10 standard….is a legislative entity and applies only to the ambient background, and a population of 25,000 people. It does not and should not, be applied to a point source such as a tunnel stack from which an entirely different composition of pollutant arises.’ The NEPM goals are no more suitable for measuring the impacts of tunnel emissions than they would be for asbestos exposure - which is also ‘particulate matter’! A real plan for improving air quality must be assessed and regulated using valid and appropriate measures
RTA ‘Filtration’ planSome cleaner air in the tunnel,more dirty air out the portal
Tunnel pollution profiles for ‘RTA plan” showing: • Unacceptable PM10 level at portal • Mean trip exposure (not significantly reduced) • Distance where PM10 exceeds 500µg/m3 (unacceptably high)
The RTA “filtration” plan extracts 200m3/sec air somewhere along the tunnel, cleans it and returns it to the tunnel.Unfortunately there is no single location which gives the stated desired outcomes: • Reduction of PM10 below 500µg/m3 (no visible pollution)for most of the tunnel length • Significant reduction or complete removal of pollutants from portal emissions • Preservation of the amenity of residents at the portal In addition, the cost is inordinately high for the limited benefit gained RAPS believes that the plan clearly fails to meet its stated objectives and should be rejected
RAPS’ Plan • There is an alternative to the RTA’s proposal…
The RAPS plan is based on the following principles: • It is important to improve air quality both inside and outside the tunnel. • Unfiltered portal emissions are dangerous to health and are unacceptable to local residents. They are inconsistent with any form of air quality improvement plan as they inevitably cause a deterioration in local air quality. • The RAPS proposal does not aim to produce an optimal ventilation system but is a rescue attempt to provide acceptable outcomes both inside and outside the tunnel, which is achievable without taking the tunnel out of use.
The RAPS ventilation plan consists of two interrelated parts: • 2 filtration stations, each capable of removing both particles and nitrogen dioxide from 250m3/sec of tunnel air, located as close as possible to the Bexley North and Marsh St portals and ejecting clean air upwards. • 3 ceiling mounted electrostatic precipitator cleaning units each capable of cleaning 120 to 140m3/sec air, located 900, 500 and 250 m from the Bexley North portal.
The RAPS plan is based on the following assumptions: • Air supply and extraction rates at the stack are operating at or close to maximum capacity. • The addition of fresh air at the portals will significantly improve air quality inside the tunnel - except for the west end of the westbound tunnel. • Removal of particles alone (without removal of nitrogen dioxide) will significantly improve air quality in the westbound tunnel • Removal of particles must be done at several locations to give satisfactory results.
Possible filter station locations Footprints of possible filter station buildings at Bexley North and Marsh St., Arncliffe located so as to access the tunnel below. Both buildings are 35 x 10m . The Marsh St building is located partially above the tunnel control centre. The RTA has suggested an alternate, suitable site.
Cleaning station concept based on filter station design by CTA for Madrid air cleaning station. • Cleaning capacity is for 250 m3/sec for both particles and nitrogen dioxide
Particle level (“haze”) reduction in west bound tunnel.Using in-tunnel filtration units in existing jet fan locations • At each of 3 locations, 120-140m3/sec particle cleaning (16 EP modules) fitted as shown. • Air flow rates of >8m3/sec per module can be achieved by using new power supplies with little loss of efficiency. • Wash down would require less than 1 hour per station once a week.
Particle level (“haze”) reduction in west bound tunnel. • 3 EP filter stations, each cleaning 140m3/sec, give satisfactory results under the worst conditions. • Results are significantly better (about 50%) than best ‘RTA’ outcome (however more equipment is involved). • Installation is by extensive use of prefabrication for the platform and cleaning units to minimise tunnel closure.
Economic aspects - operational • Additional costs. • Maintenance operations • Fans in cleaning station • Carbon replacement ($A200,000 pa) • Reduced costs. • Reduced fan usage (cross over fans, jet fans) • Night time operation (all main ventilation fans) Between 9pm and 5am tunnel can be operated in full longitudinal mode with all main ventilation fans off and no stack emissions.
Environmental advantages of whole ‘plan’, including new fans, increased air flows and ‘RAPS’ filtration solutions. • No portal emissions. • Reduction of in-tunnel particle (haze) levels by 30 - 50%, depending on location. • Reduction of stack emissions by about 40% (day time). • Total removal of stack emissions between 9pm and 5 am (20% of total emissions). • Reduction of energy consumption by night time operational changes: 10-15% (estimate). This would represent a clear ‘win’ for the whole community, with everyone gaining improved outcomes
EP filter NO2 carbon Pre filter Tunnel SHAFT