Information Paper D10 "Groundborne Noise and Vibration"

The Promoter and Camden London Borough Council as lead authority have reached agreement as to the measures that will be put in place to control the effects of groundborne noise and vibration that might otherwise arise from the construction and operation of the railway in the Crossrail tunnels. The measures are set out and explained in Information Paper D10 "Groundborne Noise and Vibration".

For ease of reference the relevant paragraphs from the information paper relating to each of these areas of agreement are presented below.

Paragraphs 1 and 2.1 introduce the Information Paper and the issue of groundborne noise.

1. Introduction

1.1 This Information Paper explains the measures that will be put in place to control the effects of groundborne noise and vibration that might otherwise arise from the construction and operation of the railway in the Crossrail tunnels.

2. Groundborne Noise

'2.1 Groundborne noise could arise from the movement of trains in Crossrail tunnels, during construction of the railway, during commissioning of the railway, or once the railway is operating passenger services'.

Significance criteria and performance specification

Paragraphs 2.2, 2.3, 2.4, and Table 1 describe the levels of significance for groundborne noise which were used in the assessment carried out for the Crossrail Environmental Statement and which have also been adopted as part of the performance specification of the Crossrail railway.

'2.2 There are no UK legislative standards or criteria that define when groundborne noise becomes significant. Crossrail has therefore drawn upon available experience in constructing new underground railways, e.g. the Jubilee Line Extension, Thameslink and High Speed 1 (Channel Tunnel Rail Link). All of these projects adopted a design criterion for groundborne noise in residential properties of 40dBL_AMax,s. This criterion was therefore adopted to assess the significance of potential groundborne noise impacts in residential properties during both construction and operation of Crossrail.'

'2.3 In the case of buildings lawfully used as reference libraries, lecture theatres, auditoria, theatres, hospitals, places of meeting for religious worship, schools and similar buildings, the use of which is particularly sensitive to noise or vibration, either the same or more stringent assessment criteria were adopted. The thresholds of significance used to assess the groundborne noise impacts of Crossrail are presented in Table 1 below.'

'2.4 These criteria will be adopted as the performance specification for the railway as the detailed design is developed. They do not apply to the noise of the tunnel boring machine (TBM) passage, including other tunnelling related activities, which is short-term and transitory and which was therefore qualitatively described in the Crossrail Environmental Statement and assessed as likely to have no significant impact.'

Control of groundborne noise during the construction of Crossrail is addressed in paragraph 2.4 of the information paper (quoted above) in relation to tunnel boring machines.

Mitigation measures assumed available in the assessment of groundborne noise from the construction railway at the time of the Environmental Statement are given in the bullet points under paragraph 2.5.

'2.5 The potential impact for construction and operation of the railway is set out in the Environmental Statement. The assessment assumes that where necessary, the potential impact is mitigated.

For the temporary railway during construction the mitigation measures available were assumed to be:'

• 'the use of smooth track (new rail without corrugations or discrete irregularities) will be installed at the start of the works with joints achieving variation in rail height of not more than 2mm;
• where appropriate the use of adequate elasticity in the track support system in order to reduce the transmission of vibration and groundborne noise from the passage of rail vehicles, for example the use of resilient rail pads in the fastening system between the rails and the sleepers.
• a speed limit on construction trains of 15km/h;
• all diesel locomotives used will be fitted with efficient exhaust silencers; and
• a maintenance programme that ensures the condition of the track does not deteriorate over time thereby causing noise in breach of the agreed threshold.'

Control of groundborne noise from the operation of the temporary construction railway is addressed in paragraph 2.6-2.7. Paragraph 2.6 of the information paper also describes the findings of this assessment i.e. no significant impacts were predicted.

'2.6 The findings of the assessment (reported in the Environmental Statement) show that adoption of these measures is likely to result in the criteria for the performance specification for residential buildings, offices, hotels, schools, colleges, hospitals, laboratories and libraries not being breached at any location during the construction of Crossrail.'

'2.7 The nominated undertaker will endeavour to ensure that the groundborne noise from the operation of the temporary construction railway that is experienced by any theatre, large auditorium/concert hall, studio, place of meeting for religious worship, court, lecture theatre or small auditorium/hall, does not exceed the levels to which it is already subject by the presence of London Underground, other railway and road transport operations, or the levels listed in Table 1, whichever is the higher noise level, during the periods for which the buildings are in use'.

Measures assumed available in the assessment of groundborne noise from the operation of the permanent railway at the time of the Environmental Statement are given in the bullet points under paragraph 2.8 of the information paper. The findings of the assessment of groundborne noise impacts from the operation of the permanent railway are given in paragraph 2.12.

'2.8 During operation after construction, the following measures were assumed to be available:

standard trackform design to use continuously welded rail;

the rails in tunnels will be supported on resilient track support systems, and track installation will be carried out using modern technology to achieve very much more accurately laid and smoother track than exists in traditional tube tunnels; and

floating slab track or similar technology, including where it is predicted that standard trackform would result in the criteria in Table 1 being breached.

Control on groundborne noise in the design and maintenance of the permanent railway are addressed in paragraphs 2.9, 2.10, 2.11, 2.13 and 2.14'.

'2.9 The nominated undertaker will be required to design the permanent track system so that the level of groundborne noise arising from it near the centre of any noise-sensitive room is predicted in all reasonably foreseeable circumstances not to exceed the levels in Table 1. The nominated undertaker will be required to install the permanent track using a standard track system for the Crossrail tunnel sections. In any location where the standard system is predicted during detailed design to cause levels of groundborne noise exceeding the relevant assessment criterion an enhanced track support system will be installed.'

'2.10 The nominated undertaker will put in place measures that will ensure that at no point during the operational life of the Crossrail passenger service will the combined power spectral density of the wheel and rail roughness amplitudes be worse than 30 dB re 1 micron in the 1/3 octave centred on a wavelength of 2m, decreasing by 15dB per tenfold reduction in wavelength.'

'2.11 Prior to opening, the nominated undertaker will ensure that the rails of the underground sections of Crossrail are conditioned by grinding, or other suitable means, and are appropriately maintained thereafter. The nominated undertaker will be required, as part of the final track design development, to provide details to the local authorities addressing the frequency of routine maintenance regimes, and the criteria under which maintenance activities such as wheel turning and rail grinding will be triggered, to demonstrate that Best Practicable Means will be adopted in respect to those matters so far as relevant for the purpose of maintaining the system to achieve the performance levels set out in Table 1 above.'

'2.12 The findings of the assessment (reported in the Environmental Statement) show that adoption of these measures is likely to result in the criteria for the performance specification not being breached at any location during the operation of Crossrail.'

'2.13 In recognition of the Local Authorities' preference for groundborne noise levels within residential dwellings which are no greater than 35dBL_Amax,S during the operation of Crossrail, the nominated undertaker will provide the information identified in paragraph 4.2 to the relevant Local Authority where any residential property is predicted through modelling as being likely to experience noise levels exceeding 35d L_Amax,S.'

'2.14 Further as paragraph 1.5 of the Environmental Minimum Requirements explains, the nominated undertaker will use reasonable endeavours to adopt mitigation measures that will further reduce any adverse environmental impacts caused by Crossrail, insofar as these mitigation measures do not add unreasonable costs to the project or unreasonable delays to the construction programme. This requirement will be applied to any residential property in which the level of groundborne noise arising from the operation of the Crossrail passenger service near the centre of any noise-sensitive room is predicted to equal or exceed 35dBL_Amax,s.'

Controls on groundborne vibration in the design of the permanent railway are addressed in paragraph 3.1 and Table 2 in the information paper.

'3.1 During the detailed design stage referred to in paragraph 2.9, the nominated undertaker will also be required to design the permanent track system, in accordance with the guidance in British Standard 6472:1992 "Guide to evaluation of human exposure to vibration in buildings (1 Hz to 80 Hz)", so that operational vibration arising from it at buildings identified in Table 1, expressed as vibration dose value (VDV), is predicted in all reasonably foreseeable circumstances not to exceed the levels presented in Table 2'

'3.2 The nominated undertaker will endeavour to ensure that the groundborne vibration from the operation of the construction railway that is experienced by any theatre, large auditorium/concert hall, studio, place of meeting for religious worship, court, lecture theatre or small auditorium/hall, does not exceed the levels to which it is already subject by the presence of London Underground, other railway and road transport operations, or the levels listed in Table 2, whichever is the higher vibration level, during the periods for which the buildings are in use.'

Section 4 of the information paper explains how the nominated undertaker will be required to apply the design criteria to the design of the railway.

'4. Application of the Crossrail Design Criteria to the Design of the Permanent Track System'

'4.1 The nominated undertaker will be required to do the following in relation to the permanent track system for the tunnel sections

(a)At design stage, to apply the relevant Crossrail design criteria relating to tables 1 and 2 which are referred to above to predict, through the use of appropriate modelling, the engineering requirements of the track system to meet those criteria.

(b)In acting under paragraph (a) above, to design a standard trackform for the tunnel section with the objective of meeting as many of those design criteria as can reasonably be achieved by such a standard track system and to design an enhanced trackform, such as floating slab or alternative better technology, for locations where it is predicted that the standard track system will not meet the criteria or to discharge other project commitments and undertakings.

(c)To translate the engineering requirements established under paragraphs (a) and (b) above into contract specifications for the permanent track system.

(d)To procure and install a permanent track system to meet the contract specifications established at (c) above.'

'4.2 The nominated undertaker will be required to provide details of the steps taken and to be taken in accordance with paragraph 4.1 above to the relevant local authority, whose comments will be taken into account, including modelling results and details of the type of rail/and or track support system proposed and its predicted performance, and to continue technical discussions concerning groundborne noise issues with local authorities. In accordance with paragraph 2.13, this will include any situation where groundborne noise levels are predicted to exceed 35dBL_AMax,s but be less than 40dB_Lamax,s in residential properties.'

The requirements of groundborne noise and vibration modelling are addressed in paragraph 5.1.

'5.1 For the detailed design of the permanent track system in Crossrail tunnels, the Nominated Undertaker will be required to adopt a groundborne noise and vibration prediction model that is fully compliant with the guidance provided in ISO 1487-1:2005 Mechanical Vibration—Groundborne noise and vibration arising from rail systems—Part 1: General Guidance, and will provide details of the model development, calibration, validation and verification procedures undertaken to comply with that guidance and the resulting model accuracy to the Local Authorities whose comments will be taken in to account.'

Information Paper D9 "Noise and Vibration Mitigation Scheme"

The Promoter and London Borough of Tower Hamlets as lead authority have reached agreement on Information Paper D9, "Noise and Vibration Mitigation Scheme". The noise and vibration mitigation scheme makes provision for mitigation in the form of noise insulation and/or temporary re-housing to be provided in circumstances where construction noise is predicted to exceed certain levels over particular periods of time. Information Paper D9 describes how the scheme will work, and how eligibility will be assessed.

An introduction to the scheme is given in paragraphs 1.1 to 1.4.

'1.1 The construction of Crossrail will cause noise and vibration impacts in some locations.'

'1.2 During construction, the Secretary of State will seek, through design and mitigation, to control the effects of noise and vibration from within the construction site. Nevertheless, there will be circumstances in which noise impacts will arise which will need to be mitigated still further. In certain circumstances, explained below, the Secretary of State or his agent will either provide and install free of charge, or provide grant aid for, noise insulation. In certain cases where the level of noise created by construction activity is predicted to be acute, the Secretary of State or his agent will contact you to arrange temporary re-housing, or help residents to arrange it for themselves and recoup the costs from the Secretary of State or his agent.'

'1.3 The Secretary of State has adopted a set of noise and vibration thresholds in relation to the provision of grant aid for noise insulation and, if appropriate, temporary re-housing. These thresholds follow the precedents established by recent and similar major schemes'

'1.4 The purpose of this information paper (IP) is to explain both how the noise insulation and temporary re-housing schemes work, and what you should do next if you think that you may be eligible for either scheme.'

A number of important definitions are given in section 2.

'2 Definitions'

'"A-weighted" is the A-weighted level, expressed as "dB(A)", allows for the frequency dependent characteristics of hearing. Corrections are applied for each octave frequency band, and the resultant values summed, to obtain a single overall level;'

'"claimant" means an owner or occupier of an eligible building who makes a request, or is made an offer under the Crossrail Noise and Vibration Mitigation Scheme;'

'"construction" includes demolition and execution;'

'"contiguous façade" means a façade of a building that is horizontally separated from other facades by a stairwell, corner or some other discontinuity;'

'"decibel (dB)" is the ratio of sound pressures which we can hear—a ratio of 106 (one million: one). For convenience, therefore, a logarithmic measurement scale is used. The resulting parameter is the 'sound pressure level' (Lp) and the associated measurement unit is the decibel (dB). As the decibel is a logarithmic ratio, the laws of logarithmic addition and subtraction apply;'

'"eligible building" has the meaning assigned to it in regulation 7 of Statutory Instrument 1996 No. 428, The Noise Insulation (Railways and Other Guided Transport Systems Regulations 1996 excluding that part of regulation 7 (1) which refers to distances from running rail or the nearest apparatus corresponding thereto which is not applicable to noise from construction sites, but does not include any building with respect to which a notice to treat has been or is intended to be served for its acquisition, or with respect to which a vesting declaration for its acquisition has been or is intended to be made;'

'"eligible room" means a living room or a bedroom having a qualifying door or a qualifying window in an eligible building;'

'"equivalent continuous sound pressure level (Leq)" another index for assessing overall noise exposure is the equivalent continuous sound level, Leq. This is a notional steady level which would, over a given period of time, deliver the same sound energy as the actual time-varying sound over the same period. Hence fluctuating levels can be described in terms of a single figure level. The A-weighted Leq is denoted as LAeq.'

'"façade" means an outer wall of a building';

'"insulation work" means work carried out to insulate an eligible building against noise which will include adequate ventilation and may include blinds;'

'"Nominated Undertaker" means the organisation or organisations which will be appointed by the Secretary of State to design, construct, operate and maintain Crossrail;'

"pre-existing ambient noise" means the level of ambient noise, expressed as a level of LAeq determined with respect to the relevant time period and the relevant LAeq averaging time, prevailing one metre in front of relevant windows or doors in a façade of a dwelling, immediately before the placing of a contract for the construction of the relevant part of the Crossrail works;'

'"qualifying door" means an external door opening directly into an eligible room which is in that part of the façade in respect of which the relevant noise level satisfies the requirements of Appendix A of this Information Paper or meets the criteria for a contiguous façade as set out in Appendix B;'

"qualifying window" means a window in an eligible room which is in that part of the façade in respect of which the relevant noise level satisfies the requirements of Appendix A of this Information Paper or meets the criteria for a contiguous façade as set out in Appendix B;'

"the Regulations" means the Noise Insulation (Railways and Other Guided Transport Systems) Regulations 1996;'

'"the relevant specifications" means the items in Part I of Schedule 1 to the Regulations except where they are amended by the provisions of this Information Paper, such of the items in Part II of Schedule 1 to the Regulations as may be approved by the Secretary of State and such of the specifications set out in Part III of Schedule 1 to the Regulations as are applicable in the circumstances of the case or items whose performance is equivalent thereto;'

'"the works" is the construction works required for Crossrail which fall within the remit of the Crossrail Construction Code.'

Paragraphs 2.1 to 2.4 explain the circumstances under which noise insulation and/or temporary housing will be offered.

'2.1 Construction noise insulation and temporary re-housing arrangements apply to dwellings and other buildings lawfully used for residential purposes.'

'2.2 To be eligible you must own or occupy a private dwelling and the dwelling must be one in which the predicted or actual construction noise exceeds the relevant "noise trigger level" (as shown in Appendix A) for:

• 'a period of 10 or more days of working in any 15 consecutive days; or'
• 'for a total of 40 days or more in any 6 consecutive months.'

'The rooms to which this scheme applies, eligible rooms, are defined as living rooms or bedrooms having a qualifying door or a qualifying window in any eligible building. On your behalf the Secretary of State or his agent will prepare the predictions and monitor the actual noise levels in consultation with the relevant local authority.'

'2.3 Initially eligibility for the scheme depends on the predicted noise level following the assessment that will be carried out for that purpose once detailed construction plans are in place. If those noise predictions indicate that a property is eligible, the offer of noise insulation will be made and, if accepted and all necessary approvals obtained, the insulation installed before the works commence. However, the actual noise may turn out to be more or less than the prediction and therefore the noise levels will be monitored as work progresses. If it is found that noise levels are not as high as expected, the insulation package will not be removed. If it is found that the noise levels are higher than expected and meet the thresholds set out in this Information Paper, you will be informed and the provisions set out in paragraphs 9.5 to 9.11 will apply. Full details of the noise trigger levels, for both noise insulation and temporary re-housing are set out in Appendix A.'

'2.4 Some buildings and/or their occupants will be treated as special cases:'

• 'Mobile homes (e.g. the travellers' site at Eleanor Street in East London) and houseboats will be treated on a case by case basis. Given that noise insulation does not represent a viable option for mobile homes, where eligibility is confirmed, appropriate alternative mitigation measures will be adopted. The sorts of measures that will be considered include works management methods (e.g. adopting quiet times, rescheduling works, and imposing noise limits), or where this is not effective or appropriate, temporary re-housing will be offered even if the Temporary re-housing thresholds are not exceeded.'
• 'Night workers, those needing a particularly quiet home environment to work in, or those that have a medical condition which will be seriously aggravated by construction noise, will also be considered on a case by case basis.'

'Whilst these discretionary arrangements only apply to residential properties, buildings which may be particularly sensitive to noise (including, commercial, educational and community) will be subject to individual consideration by the Secretary of State or his agent on the application of any body or person responsible for, or holding a legal interest or estate in, any such building.'

Paragraphs 3.1 to 3.6 explain what noise insulation involves (e.g. additional glazing, ventilation and blinds).

'3. What is the Noise Insulation Package?'

'3.1 The package will consist of:

• Secondary glazing or thermal double glazing (see also sections 5.1, 5.2 and 5.5) for living room and bedroom windows on eligible facades, plus additional ventilation if required under the relevant specifications.
• Blinds, for south facing windows.
• Insulation treatment for external doors on eligible facades.'

'3.2 Depending on the type of window you already have, secondary glazing will usually comprise another pane of glass in its own frame (wood, metal or plastic) 100-200 mm inside the existing window. This can be opened for cleaning or ventilation.'

'3.3 Secondary glazing works best when closed—so additional ventilation is usually required. The package includes an electric ventilator fan in a slim metal cover, fitted inside the room in question, to an outside wall (a 75-100 mm hole is drilled through the wall, through which the fan draws in air from the outside).'

'3.4 On a south facing window secondary glazing may make the room too hot. As set out under the relevant specifications, subject to the agreement of the claimant, blinds will be fitted between the main window and the secondary glazing to minimise this effect. If the claimant chooses not to accept blinds as part of the noise insulation package the possible impacts of this will be explained to them, blinds will not be retrofitted post installation of the noise insulation package should the claimant change their mind at a later date.'

'3.5 The Secretary of State or his agent may be able to install a "secondary" door to improve noise insulation. If the design of your house prevents this, other methods can be used, such as sealing strip between the existing door and its frame.'

'3.6 There may be circumstances in which it is not possible to fit secondary glazing. Such cases will be considered on a case by case basis. Where eligibility is confirmed, appropriate mitigation measures will be adopted. The sorts of measures that will be considered include works management methods (e.g. adopting quiet times, rescheduling works, and imposing noise limits), or temporary re-housing even if the Temporary Re-housing thresholds are not exceeded.'

Paragraphs 4.1 to 4.5 cover the actual process and the terms under which noise insulation would be offered

' 4.1 Once the Secretary of State or his agent has conducted an initial survey and the details of the insulation for your house are agreed with you, the Secretary of State or his agent will either offer to do the work at his expense, or offer grant aid for you to carry out the works.'

'4.2 The Secretary of State asks you to ensure that you provide adequate access for the survey and installation; and if you should incur expense in arranging access, the Secretary of State or his agent will reimburse you provided he has agreed the amount before the cost is incurred.'

' 4.3 In the cases where the Secretary of State or his agent offer you a grant so that you can have the work done yourself, the grant would be made on the following conditions:

(i)  You must first obtain 3 independent written quotations.

(ii)  The work must comply with the relevant specifications.

(iii)  You must select the quote that represents the best price for complying with point ii, above.

(iv)  The amount of the grant will be for whichever is the lesser amount of either your selected quote, or the actual cost of the installation.

(v)  The Secretary of State or his agent may pay 10% of the estimated cost in advance, and the balance when the work is satisfactorily completed.

(vi)  The work must be completed within 12 months of any advance payment, or before completion of the Crossrail construction works for which insulation is needed, whichever is the earlier. If this condition is not complied with, no further grant will be paid, and any payments already made will have to be repaid to the Secretary of State or his agent.

(vii)  You must obtain the consent of any other person or body that may be required to permit the carrying out of insulation work (e.g. your landlord if you are a tenant, or any consents required from your local authority).'

'4.4 Please note that the Scheme can not be used for work needed to remedy existing building defects.'

'4.5 The scheme also covers the making good of the existing fabric and decoration (not including curtains) after the installation of double windows, ventilation equipment, and second doors, including the adaptation of any existing pelmet and curtain rack.'

Answers to frequently asked questions regarding noise insulation are provided under Section 5, paragraphs 5.1 to 5.10.

'5. Frequently Asked Questions relating to Noise Insulation'

'5.1 Is secondary glazing the same as double glazing? No. Secondary glazing is a separate pane of glass installed 100-200 mm inside the existing window, and the existing window remains in place. Double glazing consists of two panes of glass in the same casing, typically around 20mm apart which replace the existing window.'

'5.2 What if I already have double glazing? The noise assessments are based on the expected noise immediately outside the building so the type of glazing you currently have installed would not affect your eligibility under the scheme (subject to 5.4 below). You are not obliged to accept the offer of insulation if you do not think you need it. The Secretary of State or his agent will provide advice as to the effectiveness of any currently installed double glazing in terms of attenuation of external noise compared to the offer of secondary glazing. You may, at your own discretion, and accepting the reduced level of noise attenuation, choose only to have ventilation units and blinds installed.'

'5.3 What if I choose not to accept the offer of noise insulation but subsequently wish to adopt it? A decision to accept an offer of noise insulation must be made within a certain timeframe. Specifically an offer must be accepted no later than 6 months after the date it is made in writing to you or one month before the Secretary of State or his agent intends to install the other noise insulation at eligible properties affected by the same Crossrail construction works, whichever is the sooner. In the latter case, you will receive notice of the cut-off date for acceptance at the time the offer is made or shortly thereafter. If you do not respond within the time-frame due to circumstances beyond your control, the secretary of state will give due consideration to your case but the construction works will continue as programmed. If you choose not to accept the offer of noise insulation there is no scope to change your mind later. However, if the noise levels change during the course of the works such that you would be eligible for temporary re-housing, then the process set out in paragraphs 9.5 to 9.11 will apply.'

'5.4 What if I already have secondary glazing installed as the result of a grant from another public works scheme? If your home has already had insulation work carried out or a grant for such work in respect of another public works scheme (such as a road or earlier railway works) you will not be eligible for further work or grant from Crossrail. However, the existing noise insulation will be inspected to ensure that it is in a state adequate to attenuate the construction noise to the extent that it should. If it is not, the works will be carried out or a grant made to have them carried out to bring the installed noise insulation package up to the appropriate standard.'

'5.5 What if I have already had secondary glazing or thermal double glazing installed privately i.e. not as the result of a grant from another public works scheme? If you have had a noise insulation package (i.e. secondary glazing or thermal double glazing, plus ventilation units and blinds) installed privately since the Crossrail Bill was deposited in February 2005, it will be inspected to check whether it is in a state adequate to attenuate the construction noise to the extent that it should. If the Secretary of State or his agent identifies that you are eligible for noise insulation following the procedure set out is section 8 of this IP, and the package meets the specification of the works set out in this IP, the person who incurred the cost of those works can receive a grant in respect of the work already done. The amount of that grant will be for the full amount (as qualified by section 4.3 (iv) and, in the case of thermal double glazing, section 5.6), and excluding any element of cost attributable to work in excess of the specification for the works in this IP, if you have followed the procedure for seeking and selecting a quotation set down in sections 4.3 (i) and (iii) of this IP for private installation. If you have not followed that procedure, the Secretary of State or his agent will make a grant to the amount that he would have offered if the procedure set out in section 8.1 for his carrying out the works had been followed. If the noise insulation package does not meet the specification set out in this IP, the works will be carried out, or a grant made to you to have them carried out, to bring the installed noise insulation package up to the appropriate standard. In addition, the Secretary of State will make a grant to the person who incurred the cost of the work previously carried out to the amount of the difference between:

• The amount he would have offered if the procedure set out in section 8.1 for his carrying out the works meeting the specification had been followed; and,
• The cost of the remedial works to bring the installed package up to the appropriate standard. If the cost of the remedial works is greater than the amount of grant that would have been paid under the procedure set out in section 8.1 then no such further grant will be paid.'

'5.6 Can I just have thermal double glazing installed instead of secondary glazing? Once an offer of noise insulation has been made pursuant to section 4.1, thermal double glazing can be provided instead of secondary glazing only if it is specifically requested by the claimant. The claimant will be made aware of the potential shortfall in sound insulation performance of the thermal double glazing compared to the secondary glazing. The amount of the grant payable for the installation of thermal double glazing will be no more than the cost of installing the secondary glazing package specified in this information paper. If you arrange for the work to be carried out yourself, the amount paid to you in reimbursement will be for no more than the cost that would have been incurred if the secondary glazing package specified in this information paper had been installed. The Secretary of State or his agent will calculate the cost that would have been incurred for installing the secondary glazing package using the experience gained from installing it in the nearest similar properties. Neither secondary nor thermal double glazing can be provided without additional ventilation and or blinds where required to comply with the Noise Insulation (Railways and other Guided Transport Systems) Regulations 1996, Schedule I, Specifications.'

'5.7 If I choose to just have thermal double glazing installed instead of secondary glazing and find later that due to the noise impact I would like secondary glazing due to the construction noise can I claim again? No. As noted in 5.6, the claimant will be made aware of any potential shortfall in sound insulation performance of the thermal double glazing compared to the secondary glazing. If the claimant elects to take a grant for the installation of thermal double glazing no further grant will be made or works undertaken to later install secondary glazing on top of the thermal double glazing.

'5.8 Can I take the grant and not do the works? No. If a grant is offered and you accept it, you must have the works carried out to the specification in the offer. Otherwise you must repay the grant. You are not obliged to accept the offer if you do not think you need it. See also para 4.3 (vi).'

'5.9 What if my landlord / tenant does not want the work carried out, but I do? The Secretary of State will try to reach agreement between all parties where possible. In any event, the party wishing to have the work carried out is requested to do all that they reasonably can to reach agreement with all other interested parties that can influence whether or not the work can be carried out.'

'5.10 Will there be a maintenance grant for the noise insulation package? No. There will be no obligation to repair, maintain or make any payments in respect of repairing or maintaining any equipment or apparatus installed under the application of this IP or to pay for the running costs, which will be minimal for mechanical ventilation units. Notwithstanding this, should equipment such as the ventilation units fail after installation of the noise insulation package through no fault of the resident, and this occurs during Crossrail construction works, the failed apparatus will be repaired or replaced as necessary.'

Paragraphs 6.1 to 6.4 cover the process under which temporary re-housing would be offered, the options available and the terms which would apply.

'6. What is the Temporary re-housing Package?'

'6.1 If, following the assessment that will be carried out for that purpose once detailed construction plans are in place, the predicted or actual (see section 9) construction noise level exceeds the trigger level for temporary re-housing, the Secretary of State will notify you that you are eligible for alternative temporary accommodation.'

'There are two options:

Option A—to arrange temporary alternative accommodation to meet your agreed needs, or

Option B—to provide information and guidance to help you arrange your temporary alternative accommodation.'

'6.2 If you choose Option A, the services provided by the Secretary of State will include arranging for:

• Temporary alternative accommodation (which, where appropriate, could be a local hotel or guest house).
• Removals.
• Storage and insurance of your personal effects.
• Insurance for the house you vacate.
• Where appropriate your pets to go into kennels, catteries etc.
• Where appropriate the disconnection and later reconnection of gas, water, electricity etc.'

'6.3 If you choose Option B then, instead of actually identifying the alternative accommodation and making the arrangements for you, the Secretary of State will supply you with information and guidance on all the matters listed above, to enable you to make the arrangements yourself; and the Secretary of State will also help you ensure that the costs you incur can be agreed and paid to you as soon as practicable.

'6.4 Whether you choose Option A or Option B, the Secretary of State will bear (or reimburse you with) the reasonable costs associated with your temporary re-housing together with the continuing, unavoidable costs of maintaining your own house whilst you are away. However, these will be paid less the costs that you would have paid if you had stayed in your own house over the same period.'

Paragraphs 7.1 to 7.7 list frequently asked questions in relation to temporary re-housing.

'7. Frequently Asked Questions relating to Temporary re-housing'

'7.1 Do I have to move? No. The acceptance of any offer of temporary re-housing is discretionary. You do not have to move if you do not want to. If you do decide to stay, you cannot claim compensation for disruption due to the noise of the works.'

'7.2 What happens in relation to my existing tenancy? The offer of temporary accommodation will be in addition to your current home. You will still be responsible for the rent, bills and other outgoings at your current home and you will still be a tenant there. The offer will include the additional cost of the relocation accommodation. You are free to visit and use your current home as you wish during the relocation, subject to the terms of your existing tenancy. If your tenancy agreement expires during the relocation you should (if you want to) renew it with your landlord in the normal way. If you choose not to renew your tenancy, grant to meet the cost of the alternative accommodation will cease when your tenancy expires.'

'7.3 What about insurance, mail redirection etc? Most temporary relocations will be short term. In some areas, the relocation may be longer term and you will be reimbursed reasonable additional costs which you incur due to long term absence from your property.'

'7.4 Will the temporary accommodation offered be of the same quality as my current home? The type of re-housing offered will depend on the duration of the relocation. For short durations hotel accommodation may be appropriate. For longer periods, alternative rented accommodation would be more suitable. In all cases account will be taken of your existing accommodation as far as possible.'

'7.5 How far away will I be moved? The accommodation offered will be governed by what is available at the time and your reasonable requirements. Some people may be prepared to move to another area on a temporary basis if they would be nearer friends, family or work. Others may need to stay in the same area.'

'7.6 Can I have noise insulation and temporary relocation? This will depend on the circumstances. The noise generated by the works will vary over the course of the job. In some areas, the noise may qualify for temporary relocation for one period, and noise insulation only for a different period. In these circumstances you would receive a temporary relocation offer for one period and a noise insulation offer for the other period. In other areas, a home may qualify for temporary relocation for a given period, but outside that period the noise may not trigger a separate noise insulation offer. In such a case, a temporary relocation offer only would be made and noise insulation would not be offered. If you qualify for temporary relocation but not noise insulation, you do not have to accept the offer of relocation and may request noise insulation instead. You will be made aware of any shortfall in sound insulation performance of the noise insulation in relation to the thresholds presented in Appendix A and that the degree of disturbance could be high even with the noise insulation in place. If you choose to adopt this approach and noise insulation is provided you will not be able to later request temporary relocation under this scheme.'

'7.7 I am a landlord. Will you compensate me for lost rent if you temporarily relocate my tenant? No. Your tenant will remain your tenant and remain liable to pay rent in the normal way.'

Paragraphs 8.1 to 9.11 give further details of the process by which actual eligibility for noise insulation and/or temporary housing will be established, including the process if actual noise levels are higher than predicted.

'8.1 The procedure comprises 7 steps. '

(i)  'Secretary of State or his agent will carry out an assessment in every area likely to be affected by Crossrail construction noise, so as to predict what the noise levels will be and will discuss and agree the findings with the relevant local authority.'

(ii)  'The Secretary of State or his agent will then notify owners or occupiers of buildings which, on the basis of the assessment, the Secretary of State or his agent considers qualify, and accordingly which type of assistance (noise insulation or temporary re-housing) they are eligible for. The Secretary of State or his agent will also send an application form at this stage '

(iii)  'If you receive such a notice and application form, you should complete and return the form to The Secretary of State or his agent. The Secretary of State or his agent will then assess your application and if acceptable notify you in writing.'

(iv)  'The Secretary of State or his agent will then arrange to visit you in order to discuss the application with you generally; view your home and in the case of noise insulation take any necessary measurements; and identify any special issues or requirements (such as any other approvals that may be required in the case of noise insulation).'

(v)  'The Secretary of State or his agent will then assess your case in detail and, if it is accepted, notify you of:'

• 'any further survey likely to be needed at your house, and (in insulation cases) the work the Secretary of State or his agent thinks should be done and his offer to do it; or '
• '(in re-housing cases) either his proposals to re-house you temporarily or the information and guidance you need to make your own rehousing arrangements. In either case the proposals will be discussed with you and you will not be under any obligation to accept the offer.'

(vi)  'Assuming you agree, the noise insulation package or temporary re-housing plan (as the case may be) is then put into effect.

(vii)  The Secretary of State or his agent reimburses you for any agreed costs, which you have incurred or (in grant cases) pays the balance of the grant.'

'Alternatively, the Secretary of State or his agent pays for noise insulation or removal/re-housing costs where he or his agent has done the work. A noise insulation package will not be offered if the noise trigger level is only exceeded whilst you are in temporary alternative accommodation (however see section 7.6 above).'

'9 What if I am not initially considered eligible to receive either noise insulation or temporary re-housing but it is found subsequently that I qualify?'

'9.1 The following sections address the procedure that will be followed in the case of people who consider themselves affected by construction noise and eligible for noise insulation or temporary re-housing who have not been offered either form of mitigation. Such claims may arise before or after the start of construction work.'

'Predictions of eligibility for noise insulation/temporary re-housing'

'9.2 Predictions will be carried out on behalf of the Secretary of State using the British Standard method of calculating construction noise, based on the contractor's method of working and plant lists.'

' 9.3 Noise levels received at dwellings near the construction site will only vary significantly from the predictions already produced if there has been

(i) a significant variation in the method of working or plant used from that currently anticipated or (ii) an error in the predictions.'

'Claims Before the Start of Construction'

'9.4 If a person does not receive notification of eligibility for noise insulation/temporary re-housing according to paragraph 8.1 (ii) above, they may request a copy of the noise predictions on which the determination of the extent of eligibility was based. If they consider there to be any error in the predictions (for example incorrect identification of the claimant's property) they should provide to the Secretary of State or his agent sufficient information concerning the claimed error. The Secretary of State or his agent will then reconsider the matter of eligibility and either make an offer of noise insulation/temporary re-housing or confirm that the claimant remains ineligible.'

'Claims After the Start of Construction'

'9.5 The trigger levels for eligibility for noise insulation/temporary re-housing involve both noise levels and durations (temporal criteria). There are two possible cases that may arise:

(i)  The predictions do not identify that noise insulation/temporary re-housing thresholds will be exceeded, but in practice they are and this is expected to continue for a period of time sufficient to exceed the temporal criteria.

(ii)  The predictions identify that the noise insulation/temporary re-housing thresholds will be exceeded but will not carry on for a sufficient duration to trigger the temporal criteria. However, in practice the works go on for longer and the temporal criteria are triggered. In both cases the approach will essentially be the same.'

'9.6 If a person claims, after the start of construction work, that the noise levels actually experienced are such as to cause eligibility for noise insulation/temporary re-housing where none was predicted, or that received noise levels are sufficient for eligibility for noise insulation/temporary re-housing where this was predicted, and that the noise has continued, or seems to them likely to continue for longer than the temporal triggers where that had not been predicted, the claim will be considered by the Secretary of State or his agent according to the following process.'

'9.7 A claim after the start of construction will inevitably take the form of a complaint or formal representation to the nominated undertaker. On receipt of the claim, the nominated undertaker will review the works being undertaken that have generated the claim and assess whether it is likely that the claim is valid. Where the nominated undertaker considers there is a potentially valid claim short-term site monitoring will be undertaken to identify whether the noise insulation/temporary re-housing trigger levels are indeed being exceeded. Whether or not monitoring is undertaken the nominated undertaker will discuss the results of the review with the claimant and explain the findings and any actions that have been taken.'

'9.8 At the same time, the nominated undertaker will inform the local authority that granted the Section 61 consent about the claim and what actions are being taken to address it. If the nominated undertaker considers that works are being carried out in breach of the Section 61 consent, they will ensure that all necessary steps are taken to put it right and inform the local authority of the actions taken. On being informed by the nominated undertaker about the claim and the steps being taken to address it, it is for the local authority to consider whether enforcement action should be taken pursuant to the Section 61 consent.'

9.9 If the short-term noise monitoring identifies that the noise insulation/temporary re-housing thresholds are being exceeded, but that operations are being performed in accordance with the terms of the relevant Section 61 consent, the nominated undertaker will identify whether the activities causing those levels will carry on for longer than a period of 10 or more days of working in any 15 consecutive days or for a total of days exceeding 40 in any six consecutive months. If they are not, then no further action is required. The findings will be made known to the local authority who issued the S61 consent and discussed with them.'

'9.10 If the works causing noise levels above the noise insulation/temporary re-housing thresholds are projected to go on for longer than a period of 10 or more days of working in any 15 consecutive days or for a total of days exceeding 40 in any six consecutive months, but the construction works are being carried out in accordance within the terms of the relevant Section 61 consent, then the nominated undertaker will require action to be taken to reduce the level of noise being caused, or offer noise insulation and/or temporary re-housing to the affected property as appropriate. Works will not cease during the organisation and installation of the noise insulation. However, if appropriate, temporary re-housing will be offered to cover the period during which the noise insulation is installed. The temporary re-housing will be withdrawn:

• once the noise insulation is installed; or
• if the claimant unnecessarily delays obtaining any necessary consents in accordance with paragraph 4.3 (vii). If it is not possible to fit secondary glazing appropriate measures will be considered on a case by case basis (see paragraph 3.6).'

'9.11 If the complainant is not satisfied by the response of the nominated undertaker following a claim under section 9.7 above, they may register their complaint with the Complaints Commissioner. If they are not satisfied with the response of the Complaints Commissioner, they may refer the matter to the Secretary of State who is the final arbiter for deciding whether an offer of noise insulation and/or temporary re-housing will be made.'

Paragraphs 10.1 to 10.4 of the information paper advise residents on the steps to take if they think that they might have been overlooked by the scheme.

'10. How do I start making a request for assistance?

10.1 In the majority of cases where residents are eligible, they will receive from the Secretary of State or his agent a notice and application form. Once you receive a notice, you simply complete and return the form.'

'10.2 If you do not receive a notice, but you believe you may be eligible (e.g. because your neighbours have received notices, or you have some particular reason to think you will be affected by construction noise even if you might not strictly speaking be eligible under the Scheme) please contact the Secretary of State or his agent at the address given below, and he will then consider your position individually. See also section 9.4 above.'

'10.3 Whilst every endeavour will be made to ensure all those who might be eligible under this policy receive notices and application forms, some properties may be inadvertently missed, particularly in relation to special cases where specific circumstances may not be apparent. Clearly, we would hope that such an occurrence does not occur. The Nominated Undertaker or his agents will liaise with the relevant local authority to minimise the risk of any inadvertent omissions.'

'10.4 This noise and vibration mitigation scheme will be implemented together with any relevant procedures set down in any detailed community relations plan established by the Secretary of State or his agent to ensure that residents understand how any concerns raised will be made known to the Secretary of State or his agent and the lines of communication available through which action will be initiated'.

Paragraph 11 provides contact details for residents who have further questions.

'11. I have further questions that are not answered here. Where can I get further information? Call our helpdesk on 0845 602 3813 (open 24 hours) Email us at: helpdesk@crossrail.co.uk Write to us at: Helpdesk Cross London Rail Links Ltd Portland House Bressenden Place London SW1E 5BH.'

Technical details of the eligibility criteria for the noise and vibration mitigation scheme are presented in Appendix A.

'APPENDIX A'

'1. Noise Insulation'

'Where the total noise level due to construction of the railway (pre-existing ambient plus airborne Crossrail construction noise), measured or predicted at a point one metre in front of the most exposed of any windows and doors in any façade of a building which is an eligible dwelling, exceeds whichever is the higher of either:'

'(a) any of the following criteria in Table 1:

Or

(b) 5dB above the pre-existing airborne noise level for the corresponding times of day (i.e. the Relevant Time Periods presented in column 2 of Table 1); and

for a period of 10 or more days of working in any 15 consecutive days or for a total of days exceeding 40 in any six consecutive months.'

'2. Temporary Re-housing'

'Where the total noise level due to construction of the railway (pre-existing ambient plus airborne Crossrail construction noise), measured or predicted at a point one metre in front of the most exposed of any windows and doors in any façade of an eligible dwelling, exceeds whichever is the higher of either:

(a) 10dB above any of the noise levels in the table above or

(b) 10dB above the pre-existing airborne noise level for the corresponding time of day (i.e. the Relevant Time Periods presented in column 2 of Table 1); and

for a period of 10 or more days of working in any 15 consecutive days or for a total number of days exceeding 40 in any six consecutive months.'

'3. Interpretation of the trigger levels'

'In interpreting and applying the trigger levels in Table 1, two conventions will be adopted. The first is that in interpreting the noise insulation/temporary re-housing policy where eligibility arises if noise levels in Table 1 are exceeded, a resolution of 0.1 dB will be applied. For example, a value of L_Aeq,T of 55dB (with pre-existing ambient at least 5dB lower) will not trigger eligibility. A value of 55.1dB will trigger eligibility.¹'

'The second convention relates to the choosing of minimum one-hour L_Aeq.T levels at night to define the pre-existing ambient, given that a series of survey results often shows different minima over a series of nights. The approach will be to select a 7-day survey period during which favourable weather conditions existed² and select the lowest one-hourly value from that data set.'

Further technical information describing how eligibility for the scheme will be determined in relation to airborne noise predictions at building facades are provided in Appendix B.

'Appendix B'

'As explained in the main body of this IP, eligibility for noise mitigation arises under the Scheme when three requirements are met

(i) the total predicted (or actual) noise level due to construction works (pre-existing ambient plus airborne Crossrail construction noise) exceeds a trigger level

(ii) the margin between the construction noise level plus the pre-existing ambient and the pre-existing ambient is at least 5dB and

(iii) the temporal requirements (10 out of 15 days of working etc) are met. If the eligibility requirements were applied strictly this could lead to anomalies whereby some dwellings in a terrace might be included and not others or it might result in dividing the facades of apartment blocks into eligible and ineligible properties. The procedure to be followed by the Secretary of State or his agent in implementing the Scheme so as to avoid dividing facades in a manner likely to be contentious for residents is set out below.'

'2. Procedure for Administering the Policy While construction noise predictions made using a noise model such as SoundPlan can be presented using contours that will indicate a finite value for any location of interest, the same is not true of eligibility. The principal reason for this is that measured baseline noise levels are of necessity carried out at discrete locations. While interpolation between discrete values is possible in theory, it is in many circumstances impracticable.'

'The procedure will normally identify a single representative noise measurement location per façade, except for long facades. Sometimes a noise measurement location may serve as a surrogate for other comparable facades as well. Measurement locations should generally be towards the centre of the façade or façade section that they represent. The noise measurements from these locations may well be rounded.'

'The predicted noise including the contribution from the construction works will then be made for the worst affected window in the façade under consideration.'

'Whether a property is eligible for noise mitigation or not will then be determined using this predicted level. This determination will be applied to all the dwellings for which the measurement location was taken as representative. In the case of a very long façade, it may be appropriate to utilise more than one noise measurement location. However, since measured values will vary slightly with quite small movements in position, a protocol needs to be established to avoid anomalous results as described above. The solution is to determine that more than one measurement location will be adopted for the same continuous facade only if the results from different noise measurement locations alongside the same façade differ by at least 3dB. For a façade at right-angles to a noise source such as a road or railway, this broadly means a doubling of distance from the source and would therefore normally only apply to long facades.'

'3. Protocol for Determining Eligibility

1) Establish baseline LAeq for relevant time of day for appropriate monitoring locations.

2) Assign monitoring results to facades according to the following rules:

'a. Monitoring results to apply to whole façade where there is only one monitoring location for that façade. The monitoring location is to be as near as possible to the centre of the façade.'

'b. Monitoring results to apply to whole façade where another façade is used a surrogate.'

'c. Where more than one monitoring location exists for the same façade, only if the LAeq levels for any period differ by 3dB or more shall the façade be divided, in which case façade areas around the location to be apportioned equally (i.e. as far as practicable each monitoring location to be in the centre of the area assigned to it)'.

'd. The definition of a façade of a building is one that is horizontally separated from other facades by a stairwell, corner or some other discontinuity, as set out in section 2 of this IP.

'3) The predicted noise levels including construction noise to be utilised for the whole facade are those for the worst affected window/door in any façade'.

Information Paper D9 Technical Explanatory Note

The Promoter and London Borough of Tower Hamlets as lead authority also reached agreement on a Technical Explanatory note to Information Paper D9 Noise and Vibration mitigation Scheme. The technical note is primarily intended for reference by Environmental Health Officers.

Information Paper D25 "Noise from Fixed Installations"

The Promoter and London Borough of Havering as the lead authority have reached agreement as to the measures that will be put in place to control the effects of noise from fixed installations. The measures are set out and explained in Information Paper D25 "Noise from Fixed Installations".

An introduction and description of the items that constitute "fixed installations" is given in paragraphs 1.1 to 1.5.

'1.1 This Information Paper explains the measures that will be put in place to control the effects of noise and vibration from the operation of fixed installations designed and installed by the nominated undertaker as part of the Crossrail scheme, but it does not cover rail-served or other installations provided by the nominated undertaker for other parties affected by the scheme and not intended for use by the Crossrail operator as part of the operational Crossrail system.'

'1.2 The term "fixed installations" is used to describe the following:

• forced ventilation shafts located along the tunnelled sections;
• draught relief shafts located along the tunnelled sections;
• electrical trackside equipment located along the surface railway;
• power supply facilities e.g. transformers located along the surface railway;
• mechanical ventilation and air conditioning equipment associated with Crossrail buildings including those located at depots, sidings, control rooms and stations;
• static sources of noise located at depots and sidings (for example train washes, wheel lathes and stationary trains) but excluding noise from the movement of trains; and
• public address systems and audible warning systems at stations, depots and sidings.'

'1.3 The measures that are available to control the effects of noise from each of these sources are set out below.'

'1.4 As described in the Crossrail Environmental Statement, the Crossrail scheme includes 26 tunnel forced ventilation shafts. The shafts house large ventilation fans that are sources of noise whose significance was assessed in the preparation of the ES. It is proposed to operate these fans intermittently in response to circumstances such as demands during congested running in the tunnels and emergency response.'

'1.5 To avoid a significant noise impact from the operation of the tunnel forced ventilation fans, noise attenuators will be designed and installed on each side of the tunnel ventilation fans as necessary to meet the Crossrail assessment criterion for fixed plant.'

Paragraphs 2.1, 2.2, 2.3, 2.4, describe the assessment criterion for fixed installations used in the assessment carried out for the Environmental Statement which has also been adopted as the performance specification for the Crossrail railway.

2. The Crossrail Assessment Criterion for Fixed Installations

'2.1 In accordance with BS 4142:1997 (Method for Rating industrial noise affecting mixed residential and industrial areas), the Crossrail assessment criterion for fixed installations other than public address systems and audible warning systems is founded upon the difference between the noise from the fixed installations (expressed in terms of the rating level) and the existing background noise (expressed in terms of the LA90,T noise level). The rating level takes account of tonal or impulsive characteristics of mechanical and electrical services plant.'

'2.2 The Crossrail assessment criterion is as follows: airborne noise arising from fixed installations is not significant if the predicted value, as determined for the worst-affected residential building, obtained by subtracting the existing background noise level (LA90,T) from the rating level of the fixed installations in normal operation is not more than +5dB, assessed in accordance with BS 4142:1997. For the purposes of the Crossrail Environmental Statement (ES) it was applied to existing known residential buildings, and future developments based upon the Greater London Authority's London Development Monitoring System using the most recently available data at the time.'

'2.3 The LA90,T is the A weighted noise level exceeded for 90% of the specified measurement period in the absence of the noise which is the subject of the assessment. The lowest background noise (LA90,T) levels occur at night, so any use and assessment of the operation of the fixed installations at night constitutes the strictest test. BS 4142:1997 requires that, at night, the reference time interval for determining the specific noise level is 5 minutes, and it is likely that any occasion on which a tunnel forced ventilation shaft fan will run at night will involve continuous noise for a duration of at least 5 minutes. This means that the specific noise level does not need to be corrected for duration. If the noise has distinguishing characteristics, for example, in the case of fans it is tonal, a further 5dB correction is then added and the specific noise level becomes the rating level.'

'2.4 Thus, effectively, the Crossrail assessment criterion means that, for the usual case of fan noise with an audible tone, the forced ventilation shaft fan sound level alone should not be greater than the background LA90,T noise level without it.'

Paragraph 2.5 describes the design criterion to be applied to fixed installations.

'2.5 The nominated undertaker will be required to design and construct fixed installations (including the forced ventilation shafts which will include noise attenuators on both sides of each fan and other forms of mitigation as necessary, but excluding public address systems and audible warning systems) so that, with additional allowances made for calculation uncertainty, under all reasonably foreseeable circumstances the assessment at the worst-affected residential building, as identified in the ES, obtained by subtracting the existing background noise level (LA90,T) from the rating level LAr,Tr of the fixed installations in normal operation, is not more than +5 dB, determined in accordance with BS 4142:1997.'

Paragraphs 2.6 and 2.7 describe the further endeavours to be employed in designing and constructing the fixed installations

'2.6 While the degree of attenuation required is site dependent, not least because of different levels of background noise at different sites, the nominated undertaker will (in cases not covered by paragraph 2.9 below) be required to use reasonable endeavours when designing the fixed installations to reduce the noise below the design criterion set out in Section 2.5 where it is practicable to do so.'

'2.7 In recognition of the local authorities' preference for rating levels which are no greater than LA90,T-5 for Crossrail, the nominated undertaker will prior to the commencement of procurement of equipment provide to the relevant local planning authority the following information in situations where, despite using reasonable endeavours to reduce noise levels below the design criterion of LA90,T+5 referred to in paragraph 2.5 at the worst-affected residential building, as identified in the ES, the overall rating noise levels associated with tunnel ventilation, draught relief and the operation of plant and equipment at the deep level station sites are still expected to be above LA90,T-5:

• the calculated rating levels at the most sensitive receivers under the range of operational modes anticipated, including noise from mechanical fan operation and draught relief;
• for tunnel ventilation, the frequency and duration of use of the fans expected as a result of possible congestion and train headway simulations;
• details of the performance of noise mitigation incorporated into the deep level station, ventilation shaft and headhouse structures;
• a description of the limitations to any or further mitigation being practicable.

For the purposes of the above commitment, the term 'deep-level station' refers to stations with sub-surface platforms within tunnels, accessed from ground level.'

Paragraph 2.9 describes the further endeavours required to be employed in the design of fixed installations associated with the surface railway and surface stations, paragraph 2.8 gives a definition of such installations.

Fixed Installations associated with surface railway and surface stations

'2.8 In the following paragraphs of this IP (i) references to the surface railway are to the Crossrail running lines, and do not include depots and sidings, and (ii) references to surface stations do not include any deep-level station as defined in paragraph 2.7.'

'2.9 The nominated undertaker will, notwithstanding paragraph 2.5, be required to employ best practicable means in designing and constructing the fixed installations associated with the surface railway and surface stations (including electrical trackside equipment located along the surface railway, power supply facilities e.g. transformers located along the surface railway and static noise sources associated with Crossrail at surface railway stations, but excluding public address systems and audible warning systems) with the aim of reducing noise so that, with additional allowances made for calculation uncertainty, under all reasonably foreseeable circumstances the assessment at the worst-affected residential building, as identified in the ES, obtained by subtracting the existing background noise level (LA90,T) from the rating level LAr,Tr of the fixed installations in normal operation, is not more than LA90,T-5, determined in accordance with BS 4142:1997. Where despite the employment of best practicable means, rating levels at the worst-affected residential building are expected to exceed LA90,T-5, the nominated undertaker will prior to the commencement of procurement of equipment provide to the relevant local planning authority the following information:

• the calculated rating levels at the most sensitive receivers under the range of operational modes anticipated;
• details on the performance of the proposed noise mitigation measures;
• a description of the limitations to any or further mitigation being practicable.'

Paragraphs 3.1 and 3.2 set down the protocol for the application of the Crossrail design criterion for fixed installations.

3. Protocol for the application of the Crossrail design criterion to the design of fixed installations

'3.1 With the exception of public address systems and audible warning systems which are addressed solely in Section 4 of this IP, the nominated undertaker will be required to apply the Crossrail design criterion to the totality of all fixed installations at a single Crossrail development and the specific noise source defined by BS 4142:1997 shall mean all the fixed installation noise sources (including mechanical plant and machinery) installed and operated in any location within the Crossrail development. Thus, for example, at a central London station it will apply to the design of the forced ventilation shafts, draught relief shafts and station mechanical ventilation and air conditioning equipment.'

'3.2 When designing all fixed installations other than public address systems and audible warning systems, the nominated undertaker will be required to:

• Incorporate the design criterion into contract documents such that it will apply to the design of all the fixed installations that are to be installed and operated in any location within the Crossrail development.
• When designing fixed installations, take the further endeavours which are referred to in paragraph 2.6 or 2.9 (as the case may be) to reduce the noise below the design criterion in paragraph 2.5.
• Translate the design criterion into specific requirements in specifications for the procurement and operation of Crossrail plant, equipment and machinery for fixed installations taking into account the further endeavours referred to in bullet point 2 above.
• Determine the relevant LA90,T levels, to be jointly established with the relevant local authorities.
• Procure, install and commission plant, equipment and machinery, including noise attenuation equipment that meets the specific requirements referred to in bullet point three above.
• Provide details of the measures undertaken to ensure that, under all reasonably foreseeable circumstances, the design process and procurement process for fixed installations is adequate to achieve compliance with the design criterion taking into account the endeavours referred to in bullet point 2 above (including proposals for maintenance and monitoring) to the relevant local authority whose comments will be taken into account.
• Before the fixed installation may be operated, satisfactorily complete the standard suite of acceptance tests required for such plant and provide information on those tests to the relevant local authority'

Paragraph 4.1 addresses noise from public address systems and audible warning systems.

'4. Noise from public address systems and audible warning systems'

'4.1 The nominated undertaker will be required to agree appropriate criteria for assessing noise arising from any new or materially altered public address system and audible warning systems with the relevant local authority, prior to the specification and detailed design of such systems. Such systems shall be designed to meet the agreed noise criteria. In the event that appropriate noise criteria cannot be agreed with a relevant local authority, any dispute will be resolved in accordance with the procedure set down in clause 63 of the Bill (arbitration).'

Information paper D26 "Surface Railway Noise and Vibration"

The Promoter and London Borough of Newham as the lead authority have reached agreement as to the measures that will be put in place to control the effects of surface noise and vibration from the operation of Crossrail trains. The measures are set out in Information Paper D26 "Surface Railway Noise and Vibration".

Paragraph 1.1 simply introduces the paper.

'1. Introduction'

1.1 This Information Paper provides a summary of both the assessment of surface railway noise associated with the operation of Crossrail, and the undertakings the Promoter proposes to adopt in terms of the measures to be put in place to control the effects of surface noise and vibration from the operation of Crossrail trains. It also explains how people living along the Crossrail route may perceive changes in noise as a result of changes to the rail service. More detailed technical explanations of these matters are presented in a Technical Note which has been developed primarily for use by local authority environmental health officers but is also available on request. This Information Paper does not apply to fixed installations which are covered by the Information Paper on fixed installations, Information Paper D25, Noise from Fixed Installations.'

Paragraph 2.1 lists the factors relevant to the predicted changes in railway noise.

'2.1 The predicted change in railway noise at any given location depends upon a number of factors including whether trains have been brought closer to a noise sensitive location (e.g. residential property), the speed of the rolling stock, the size and type of rolling stock, and the number of train passes at any given period.'

Paragraphs 3.1, 3.2, 3.3 and 3.4 explain the noise indices and time periods used to assess surface railway noise.

'3. Measurement and Prediction of Railway Noise'

'3.1 Railway noise is conventionally measured and assessed using the LAeq index. The LAeq is a measure of the mean square sound pressure during a period of time, in what is referred to as A weighted decibels or dB(A)'

3.2 For Crossrail, the noise assessment has addressed two different but related aspects:

• The assessment of impact based upon noise change over the daytime (07:00 to 23:00 hours, i.e. 16 hours), and night-time (23:00 to 07:00 hours, i.e. 8 hours) periods; a significant impact was deemed to occur if a change of 3 dB(A) or more was predicted.
• The assessment of potential eligibility for noise insulation (NI) under the Noise Insulation (Railways and Other Guided Transport Systems) Regulations 1996, where various criteria are assessed for the daytime (06:00 to 24:00 hours, i.e. 18 hours) and the night-time (00:00 to 06:00 hours, i.e. 6 hours) periods.'

'3.3 The overall effect of additional services associated with Crossrail is predicted to be relatively small, as it is proposed that the services would mostly use existing lines where on the surface.'

'3.4 Research into the effects on the population exposed to railway noise, indicates that it is the least annoying of all the transportation sources.'

A summary of the assessment of surface railway noise (reported in the Environmental Statement) is presented in paragraphs 4.1 and 4.2.

'4. Summary of the Assessment of Surface Railway Noise Impacts'

'4.1 As described in the Crossrail Environmental Statement (ES)¹ the Crossrail scheme runs along the surface from Maidenhead to Royal Oak Portal (the western section of the scheme); from Pudding Mill Lane Portal to Shenfield (the northeastern section); and, on its southeast section where it surfaces three times, firstly, between Victoria Dock Portal and the existing Connaught Tunnel, then between Connaught Tunnel and the North Woolwich Portal and finally, between Plumstead Portal and Abbey Wood.'

'4.2 The assessment of the western and northeastern sections of the scheme identified no significant noise and vibration impacts from the operation of Crossrail. The assessment of operational railway noise for the southeastern section identified that, following mitigation, there are likely to be adverse impacts on an estimated 20 properties. Seven of these properties are likely to qualify for noise insulation under the Noise Insulation (Railways and other Guided Transport Systems) Regulations 1996 as amended (from hereon referred to as 'the Regulations'). The majority of the properties are located around Abbey Wood station. The ES identifies the use of permanent noise barriers as a means to mitigate the operational noise impacts along the southeast section. These would be located primarily between Plumstead Portal and just east of Abbey Wood station. It is estimated that the residents of 55 properties, located primarily around Abbey Wood Station, would experience significant reductions in railway noise as a result of these barriers.'

The control of surface railway noise is addressed in paragraphs 5.1, 5.2, 5.3, 5.4 and 5.5.

'5. The Control of Surface Railway Noise'

'5.1 In circumstances prescribed by the Noise Insulation (Railways and other Guided Transport Systems) Regulations 1996 as amended, predicted changes to existing noise levels may, in the case of dwellings and other buildings used for residential purposes, lead to mitigation in the form of the provision of noise insulation.'

'5.2 The Regulations set out a requirement to carry out or make a grant toward the provision of insulation works in eligible buildings, where noise levels from new surface railway, or additional tracks that will be located next to an existing surface railway, exceed certain thresholds and triggers set out in the Regulations.'

'5.3 The new surface sections of the railway will be designed and constructed using continuously welded rail to the greatest extent practicable with the objective of reducing noise and vibration due to the operation of the surface railway.'

'5.4 The design of new surface railway, or alteration of existing surface railway tracks will endeavour to achieve, in all reasonably foreseeable circumstances, predicted² operational noise level increase less than 3dB LAeq,T at the nearest sensitive receptor identified in the ES when calculated in relation to the periods of a day (07:00 to 23:00) and of a night (23:00 to 07:00), although as mentioned in paragraph 4.2 there will be cases where noise will exceed this. The design will include consideration of mitigation measures such as noise barriers.'

'5.5 The Regulations, and hence this information paper, do not apply to stationary trains, station activities, shunting or groundborne noise.'

The control of vibration from the surface railway noise is addressed in paragraphs 6.1 and 6.2 and Table 1.

6. The Control of Vibration from the Surface Railway

'6.1 The design of the new surface railway, or altered railway, in accordance with the guidance set out in British Standard 6472:1992 "Guide to evaluation of human exposure to vibration in buildings (1 Hz to 80 Hz)", will endeavour to achieve, in all reasonably foreseeable circumstances, predicted operational vibration, expressed as vibration dose value (VDV), at sensitive receptors identified in the ES, no greater than the levels presented in Table 1'.

'6.2 Where, when carrying out that design work, vibration at sensitive receptors as identified in the ES, arising from any section new, additional or altered surface railway, is predicted to exceed the levels set out in Table 1, endeavours shall be made to include mitigation measures (for example under-ballast mats) in the design, which are predicted to result in compliance with the levels in Table 1 in all reasonably foreseeable circumstances.'

Paragraph 7.1 sets out the maintenance requirements of the surface railway and rolling stock wheels in relation to groundborne noise and vibration.

'7. Maintenance of the Surface Railway and Rolling Stock Wheels.'

'7.1 For those parts of the surface railway that are part of the National Rail network that will be modified by Crossrail, maintenance of them will remain the responsibility of Network Rail. For any parts of the surface railway for the maintenance of which a person other than Network Rail is the nominated undertaker, they are to be maintained in accordance with Railway Group and Network Rail Company Standards. With regard to the generation of vibration and groundborne noise at the wheel/rail interface, the wheels of the Crossrail rolling stock will be maintained, as a minimum, at the level defined by the maintenance requirements necessary to meet the undertaking on this issue set out in Information Paper D10, Groundborne Noise and Vibration.'

Technical Paper Surface Railway Noise and Vibration

The Promoter and London Borough of Newham as lead authority also reached agreement on a Technical Explanatory note to Information Paper D26 'Surface Railway Noise and Vibration'. The technical note is primarily intended for reference by Environmental Health Officers.

Environmental Minimum Requirements—General Principles

The Promoter and the London Borough of Havering as lead authority have reached agreement on the text of the general principles section of the environmental minimum requirements documentation. The relevant paragraphs from the general principles section are presented below together with a brief description of what they cover.

Paragraphs 1.1 to 1.3 set out the role of the controls contained in the Environmental Minimum Requirements in contributing to ensuring that the impacts that have assessed in the Environmental Statement for Crossrail are not exceeded.

'1.1 The original Environmental Statement for Crossrail was published in February 2005. It has been supplemented by a number of additional volumes as further information has become available, and in the light of proposed changes to the project¹. It is the intention of the Secretary of State to carry out the project so that its impact is as assessed in the Environmental Statement (ES). The Secretary of State will require the nominated undertaker to adhere to the arrangements provided for in the Environmental Minimum Requirements in designing and constructing the Crossrail Works.'

'1.2 This document presents the text of the relevant minimum requirements, which are referred to as the Environmental Minimum Requirements (EMR). It also contains as Annexes a series of papers which support the EMR, including the Construction Code, the Environmental Memorandum and the Planning and Heritage Memorandum. '

'1.3 The controls contained in the EMR along with powers contained in the Act and the Undertakings given by the Secretary of State will ensure that impacts which have been assessed in the ES will not be exceeded, unless any new impact or impacts in excess of those assessed in the ES:

• results from a change in circumstances which was not likely at the time of the ES; or
• would not be likely to be environmentally significant; or
• results from a change or extension to the project, where that change or extension does not itself require environmental impact assessment under either (i) article 4(1) of and paragraph 22 of Annex 1 to the EIA Directive; or (ii) article 4(2) of and paragraph 13 of Annex 2 to the EIA Directive; or
• would be considered as part of a separate consent process (and therefore further EIA if required).

Paragraphs 1.4-1.6 explain who will be bound to comply with the Environmental Minimum Requirements, and set out an additional general obligation on the nominated undertaker in relation to reducing adverse environmental impacts.

'1.4 Any nominated undertaker will be contractually bound to comply with the controls set out in the EMR and as may be developed during the passage of the Act through Parliament.'

'1.5 The nominated undertaker will in any event, and apart from the controls and obligations referred to in paragraph 1.3, use reasonable endeavours to adopt mitigation measures that will further reduce any adverse environmental impacts caused by Crossrail, insofar as these mitigation measures do not add unreasonable costs to the project or unreasonable delays to the construction programme.'

'1.6 In addition, where a statutory undertaker is carrying out development in connection with Crossrail for which it has planning permission because that development has been assessed in the ES, it will be required to comply with the controls set out in the undertakings and assurances referred to in paragraph 3.4 and documents contained in the Annexes, in so far as they are relevant and properly applicable to the undertaker. References to the nominated undertaker in those documents should be interpreted as references to the relevant statutory undertaker in such cases.'

Section 2 provides a series of definitions that apply throughout the environmental minimum requirements documentation.

'2.1 It should be noted that the term 'impact" is used in the title of the Town and Country Planning (Environmental Impact Assessment) (England and Wales) Regulations 1999 to describe the environmental outcome arising from a project, while the main body of the text of the Regulations refers to the term "effect". The EMR takes these two terms to have the same meaning. For consistency, the term used throughout the EMR is 'impact'.

'2.2 In this document the following terms shall have the meanings ascribed to them for the purpose of understanding the Environmental Minimum Requirements:

"Construction Code" means the series of objectives and measures to be applied generally throughout the construction period to maintain satisfactory levels of environmental protection and limit disturbance from construction activities, which is set out in Annex 1;

"Crossrail" means the railway that runs between the termini at Heathrow, Maidenhead, Shenfield, and Abbey Wood;

"Crossrail Works" means works in relation to the design, construction, commissioning and completion of Crossrail authorised by the Crossrail Act;

"Environmental Management System" means the management system to be developed by the nominated undertaker pursuant to Annex 3;

"Environmental Memorandum" means the memorandum relating to the environmental aspects of the design and construction of the Crossrail Works, which is set out in Annex 3;

"Environmental Statement" (ES) means the Crossrail Environmental Statement submitted in February 2005 together with all subsequent additional or supplementary volumes and errata corrections5.

"Crossrail Act" means the Parliamentary Act in respect of the Crossrail scheme given Royal Assent on …;

"Nominated Undertaker" means the organisation or organisations which will be appointed by the Secretary of State to design, construct, operate and maintain Crossrail;

"Planning and Heritage Memorandum" means the memorandum setting out undertakings given by the local authorities with respect to the handling of planning and heritage matters for the Crossrail Works arising under Schedule 7 to the Crossrail Act which is set out in Annex 2; and

"Secretary of State" means the Secretary of State for Transport.

Section 3 defines the Environmental Minimum Requirements and the nominated undertaker's obligations in relation to them.

3.1 "Environmental Minimum Requirements" means the requirements:

(i)  of the memoranda and agreements referred to in paragraph 3.2;

(ii)  of the undertakings and assurances referred to in paragraph 3.4; and

(iii)  set out in paragraphs 1.5 and 3.6 to 3.10.

3.2 The nominated undertaker shall comply with and, where required to do so by the Secretary of State, shall at such time and within such period as may be reasonably required by the Secretary of State execute and deliver memoranda and agreements on planning, heritage and related matters, in the form reasonably required by the Secretary of State, including but not limited to the Planning and Heritage Memorandum, listed building agreements and overarching archaeological written scheme of investigation.

3.3 The nominated undertaker shall comply with all undertakings and assurances as specified by paragraph 3.4 and those undertakings or assurances shall take priority over the remainder of the Environmental Minimum Requirements to the extent of any inconsistency.

3.4 The nominated undertaker shall comply with all undertakings and assurances concerning the project specified in the "Crossrail Register of Undertakings and Assurances" published by the Department for Transport or as otherwise notified to the nominated undertaker.

3.5 The nominated undertaker shall also execute and deliver to the relevant party the deeds or agreements required by those undertakings or assurances. Those deeds and agreements must be delivered and executed in the form and at the time specified in the relevant assurance or undertaking or, if no form or time is specified, as reasonably required by the Secretary of State.

3.6 Where the nominated undertaker has agreed with the beneficial recipient of an undertaking or assurance referred to in paragraph 3.4 to amend, change, waive or in any way alter the terms of that undertaking or assurance, the nominated undertaker shall notify, if relevant, the local authority of the geographical area to which the undertaking or assurance relates of the new agreed terms of that undertaking or assurance, and shall comply with the new agreed terms of that undertaking or assurance. However, the nominated undertaker is not to amend, change, waive or in any way alter the terms of a specific undertaking given by the Secretary of State to Parliament.

3.7 The nominated undertaker shall build Crossrail on the lands defined in the Crossrail Act. This does not preclude the nominated undertaker from building peripheral facilities on other land provided that the necessary approvals are obtained using the normal procedures.

3.8 In the circumstances described in the first bullet point of paragraph 1.3, if the significant adverse impacts identified in the ES are likely to be exceeded, the nominated undertaker will take all reasonable steps to minimise or eliminate those additional impacts.

3.9 The nominated undertaker shall adopt and implement the Construction Code, which is set out in Annex 1. The nominated undertaker shall develop and implement the Environmental Management Plans envisaged by the Construction Code.

3.10 The nominated undertaker shall adopt and implement the Environmental Memorandum which is set out in Annex 3. The nominated undertaker shall develop and implement an Environmental Management System, in accordance with the requirements of the Environmental Memorandum, for ensuring compliance with the nominated undertaker's environmental policy, with relevant environmental legislation, and with all the Environmental Minimum Requirements other than non-environmental aspects of undertakings and assurances. The Environmental Management System covering construction is to be developed and implemented before construction begins.

3.11 Where there are references to issues being agreed in the Construction Code, Planning and Heritage Memorandum and Environmental Memorandum, that agreement shall not be unreasonably withheld and any dispute or difference arising between the parties shall be referred to and determined by the Secretary of State.

Section 4 lists the annexes to the general principles section of the environmental minimum requirements documentation which set out certain of the Environmental Minimum Requirements. .

4.1 The following documents, which are referred to in the Environmental Minimum Requirements, are attached as Annexes:

Annex 1: Construction Code

Annex 2: Planning and Heritage Memorandum

Annex 3: Environmental Memorandum

Environmental Minimum Requirements: Construction Code—Working Hours

The Promoter and Westminster City Council as lead authority have reached agreement as to the working hour's arrangements under the Construction Code, requirements which any nominated undertaker will be contractually bound to comply with. For ease of reference the relevant paragraphs from the Code are presented below together with a brief description of what they represent.

Paragraph 3.2.1 sets out the requirement for the nominated undertaker to obtain Section 61 consents for construction works.

'3.2.1 The nominated undertaker will obtain consents from the relevant local authority under the Control of Pollution Act 1974, Section 61 (which will include noise limits and vibration limits where relevant) for the proposed construction works, as set out in section 5.1 below. The applications for consent will include details of the work to be undertaken, including proposed hours of work. All construction activities carried out on site, whether in core hours or on a 24 hour basis, will be agreed with the local authorities through the Section 61 process. All of the arrangements for working hours may be varied by agreement with the relevant local authority. The right to appeal against a withholding of consent or against conditions subject to which it is given is retained, and references to agreement are to be so construed.'

Paragraphs 3.2.2 to 3.2.3 set out the core working hours and provision for shoulder hours.

'3.2.2 Core working hours will be from 0800 to 1800 on weekdays and 0800 to 1300 on Saturday. Only non-disturbing preparatory work, repairs or maintenance will normally be carried out on Saturday afternoons or Sundays between 0900 and 1700. The nominated undertaker will adhere to these core working hours for each site as far as reasonably practicable and where feasible, operations anticipated to cause disturbance would be limited to these hours. Except in the case of emergency, any work required to be undertaken on a Sunday on sites without 24 hour activity will be agreed with the local authority in advance. There are certain exceptions to the core working hours, which are described below'.

'3.2.3 In order to maintain the above working hours, the nominated undertaker will require a period of up to one hour before and up to one hour after core working hours for start up and close down of activities. The activities to be undertaken during this period may include: deliveries to and from site; loading; unloading; arrival and departure of workforce and staff at site and movement to and from place of work; general refuelling; site inspections and safety checks prior to commencing work; site meetings; site clean up; site maintenance; and maintenance and checking of plant and machinery, but not including operation of plant or machinery giving rise to noise likely to exceed the noise trigger levels for the periods either side of the agreed core working hours as set out in the Crossrail Noise and Vibration Mitigation Scheme. The start up and close down periods are not to be considered an extension of core working hours, and particular care will be taken to limit and control disturbance to local residents during such periods. The nominated undertaker will, as far as reasonably practicable, arrange for deliveries in the start up period to take place close to the end of that period and in the close down period close to the start of that period.'

Paragraphs 3.2.4 to 3.2.16 identify activities that may take place outside of the core working hours and any particular arrangements that must be carried out in relation to them.

'3.2.4 All construction related traffic serving the Crossrail work sites will abide by the agreed hours of working for each specific location. These hours will cover the timing of deliveries, off-loading and loading from the public highway. Deliveries, other than abnormal loads, will not take place outside the core working hours and the start up and close down periods without the prior agreement of the local authority, specifically through the Environment Health Department, or as otherwise advised by the local authority. Vehicles awaiting loading or offloading will not leave engines running when not directly in use unless prior agreement has been sought.'

'3.2.5 From sites where works are not undertaken on a 24 hour basis, excavated material will only be removed by road during core working hours.'

'3.2.6 The following activities will normally be undertaken on a 24 hour per day, 7 day per week basis:

• tunnelling works together with directly associated activities (such as maintenance of tunnelling equipment, construction of cross passages and installation of tunnel linings);
• delivery of materials, consumables and plant to the tunnel face from the drive portal or access shaft and for tunnel fit out by train from tunnel logistics sites at Aldersbrook and Old Oak Common.
• transportation, storage and removal of excavated material by conveyor, barge and rail;
• track laying and internal fit out works within the stations, shafts and tunnels (including construction of the track bed and cable laying).
• operation and maintenance of items of plant and equipment needed in order to safeguard and support the works, such as fans, compressors, generators and batching plant. Any such equipment will be shielded in order to provide appropriate noise attenuation (this is covered further in section 5.3);
• Staff may also be required to collect data and samples outside normal working hours; and
• surface support to the underground work, including welfare facilities, cranage, workshops and stores.'

3.2.7 Where the nominated undertaker can demonstrate that overall progress would be significantly affected by not being able to remove excavated material outside of the core working hours, then additional hours for the removal of excavated material would be agreed with the local authority. The nominated undertaker would expect the agreement of the local authority not to be unreasonably withheld.

3.2.8 In order to safeguard the works it may be necessary for certain items of plant and equipment to be kept running 24 hours per day, which would include pumps and generators. Any such equipment will be shielded in order to provide appropriate noise attenuation. Staff may be required to collect data and samples outside core working hours at times.

3.2.9 Certain works requiring temporary possession of roads and railways for safety or operational requirements, to limit disruption to road and railway users and the travelling public, and works in connection with utilities when demand is low will need to be undertaken outside core working hours. This will include Saturday afternoon, night-time, Sunday and/or bank holiday working from time to time. On occasion longer term possessions (in excess of one week) will be required for more major works.

3.2.10 In the case of work required in response to an emergency or which if not completed would be unsafe or harmful to the permanent works, the relevant local authority will be informed as soon as reasonably practicable of the reasons for, and likely duration of, the works. The local authority will provide a telephone number and nominate an office to receive such notification, which will be reviewed regularly. Examples of the type of work envisaged would include where pouring concrete takes longer than planned due to equipment failure or where unexpected poor ground conditions, encountered whist excavating, require immediate stabilisation.

3.2.11 Where work has to be rescheduled for reasons not envisaged and is expected to extend beyond the agreed or core working hours or exceed the agreed limits and dispensation to the Section 61 consent, the nominated undertaker will apply for a variation to the Section 61 consent to the relevant local authority at least 14 days in advance of the start of those works.

3.2.12 Where rescheduling relates to work of a critical nature for reasons not envisaged and beyond the control of the nominated undertaker (such as key activities likely to delay other key activities) applications will be made where practicable at least 48 hours in advance and at least 7 days in advance if the work is expected to last for a period of 5 days or more. The variation will be sought by means of an application setting out the revised construction programme or method and the relevant noise calculations.

3.2.13 Where such working outside core hours has been discussed and accepted (as in 3.2.12 above) nearby occupiers who are likely to be affected by the works will be informed as soon as reasonably practicable by the nominated undertaker about the nature and likely duration of the works.

3.2.14 Deliveries will be arranged to minimise impacts on the road system so far as reasonably practicable. Abnormal and special loads may be delivered outside core working hours subject to the requirements and approval of the relevant authorities.

3.2.15 Where reference is made above to seeking local authority agreement then an application will be made under the Control of Pollution Act 1974, Section 61, as detailed in 3.2.1 above.

3.2.16 In relation to works on the national rail network and existing stations, please also refer to section 2.7.